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Most aspects of the lives of ectotherms are temperature dependent. Achieving the warmer body temperatures (Tb s) typically required for optimal performance can be particularly challenging for nocturnal ectotherms. Homonota darwinii-the world's southernmost gecko-is broadly distributed in southern Argentina (35-52 °S latitude) where cold climates over parts of its range likely pose an additional performance challenge for this nocturnal lizard. We hypothesized that the southernmost populations of this species would be the most thermally challenged, as evidenced by a decline in temperature-dependent sprint performance with increasing latitude. A temperature-dependent depression in locomotory performance may indicate suboptimal performance in other thermally dependent traits linked to fitness (e.g., foraging efficiency, metabolism). We measured sprint performance at five ecologically relevant Tb s for four populations spanning most of the latitudinal range of H. darwinii. We also recorded annual operative temperatures (Te s) at each site on the surface and in refuges used by the geckos. Sprint data indicated differences in maximum performance over the range of H. darwinii, but not the latitudinal decline predicted. Instead, sprint performance was likely influenced by climatic variability associated with each site's elevation. Geckos from most populations had a broad range of Tb s over which sprint performance was optimal, albeit twofold to threefold lower than other geckos. This is indicative of eurythermy, the ability to perform well over a wide range of temperatures. We discuss this finding in the context of alternative hypotheses concerning performance tradeoffs in nocturnal ectotherms.

A new species of crocodile newt from populations on opposite sides of the Ayeyarwady Basin, Myanmar, previously referred to as Tylototriton cf. verrucosus, is described on the basis of colour patte...

Vertebrate taxa with entirely unisexual populations are composed of females that reproduce without fertilization and are generally of hybrid origin. At least 23 vertebrate families have unisexual lineages. Within squamate reptiles, >40 uniparental species have been described from five major lineages: acrodont iguanians, Gekkota, Serpentes, Scincomorpha, and Varanidae. Pleurodont iguanians include >1100 species, all of which have gonochoristic reproduction. Here we report the discovery of a new unisexual lizard from the liolaemid genus Liolaemus, a species-rich (∼260 species) clade distributed over most of southern South American. The new species, Liolaemus parthenos, is the only known all-female triploid pleurodont iguanian. The structural chromosome heteromorphisms of the karyotypes support the hypothesis that L. parthenos is the product of a hybrid origin. Based on morphology, the new species is assignable to the L. boulengeri group (sensu Abdala, 2007), and phylogenetic analyses of mitochondrial DNA in...

A phylogenetic taxonomic analysis of a monophyletic subgroup of the salamandrid genus Tylototriton revealed that a newly discovered population from Ngar Su Village, 1 km south of Ywangan, Shan State, Myanmar is a new species and most closely related to T. shanorum from approximately 80 km to the west in the vicinity of Taunggyi, Shan State. Tylototriton ngarsuensis sp. nov. differs from other closely related species of Tylototriton on basis of varying combinations of characteristics associated with it shorter head, larger size, rib nodule morphology, and overall drab, very dark, coloration, along with its genetic differentiation. Tylototriton ngarsuensis sp. nov. also appears to breed later in the year than most other species. Unfortunately, this species like many other Asian newts, is being harvested for the pet and medicinal trade and given its restricted distribution, this could pose a serious threat to its long-term survival.

A phylogenetic taxonomic analysis indicates that a newly discovered population of Cyrtodactylus from the vicinity of Ywangan Town in the Shan Hills, Shan State, Myanmar is a new species (C. ywanganensis sp. nov.) and the earliest diverging member of the linnwayensis group within the previously defined Indochinese clade. The DIVALIKE+J model of a BioGeoBEARS biogeographic analysis indicates that the Indochinese clade evolved in the Shan Hills and Salween Basin of eastern Myanmar and dispersed into Indochina on at least three separate occasions from 18.6–13.4 mya. Once there, uplift of the Tenasserim Mountains and Thai Highlands created the intermedius group, the oldhami group, and C. tigroides of western and southern Thailand which form sister lineages to the linnwayensis group, yathepyanensis group, and the sinyineensis group, respectively, of eastern Myanmar. Diverging lineages within the Indochinese clade highlight the importance of the Thai Highlands and Tenasserim Mountains in that group’s evolution and speciation. The discovery of C. ywanganensis sp. nov. in karstic habitats in the Shan Hills continues to underscore the unrealized karst-associated herpetological diversity of this vast, relatively unexplored, upland region and the need for additional field studies.

Cristián S. Abdala, Diego Baldo, Ricardo A. Juárez, Robert E. Espinoza (2016): The First Parthenogenetic Pleurodont Iguanian: A New All-female Liolaemus (Squamata: Liolaemidae) from Western Argentina. Copeia 104 (2): 487-497, DOI: 10.1643/CH-15-381

Liolaemus chehuachekenk (n = 2): MLP.S 2535 (holotype), 2536 (paratype), Chubut Province, Cushamen Department, SW slope of Calcatapul Mountains, 8 km N of El Molle on Provincial Route 13, 900 m., Published as part of Cristi��n S. Abdala, Diego Baldo, Ricardo A. Ju��rez & Robert E. Espinoza, 2016, The First Parthenogenetic Pleurodont Iguanian: A New All-female Liolaemus (Squamata: Liolaemidae) from Western Argentina, pp. 487-497 in Copeia 104 (2) on page 494, DOI: 10.1643/CH-15-381, http://zenodo.org/record/269580

Liolaemus purul (n = 25): FML 24153 (holotype), FML 24154 ��� 63 (paratypes), Neuq��en Province, La Rinconada Department, 6 km N of San Ignacio on National Route 40 on way to Zapala, 39 �� 50 ' 54.4 ''S, 70 �� 39 ' 52.6 ''W, 1071 m; FML 21473 ��� 74, Neuq��en Province, Zapala Department, Parque Nacional Laguna Blanca, near park ranger station, 39 ��0 2 ' 38.5 '' S, 70 �� 19 ' 36.4 ''W, 1272 m; FML 21482, Neuq��en Province, Zapala Department, Parque Nacional Laguna Blanca; FML 21499, 21534��� 35, Neuq��en Province, Zapala Department, Parque Nacional Laguna Blanca entrance gate on Provincial Route 46, 39��0 2 ' 55.8 '' S, 70 �� 16 ' 36.2 '' W, 1306 m; FML 22187 ��� 88, Neuq��en Province, Coll��n Cur�� Department, 35 km S of Coll��n-Cur��; FML 22211, Neuq��en Province, Coll��n Cur�� Department, 2 km S of Coll��n Cur�� bridge; FML 24164 ��� 65, Neuq��en Province, Zapala Department, on Provincial Route 13 on way to Primeros Pinos, 38 �� 52 ' 16.1 ''S, 70 �� 19 ' 17.9 ''W, 1275 m; FML 24166 ��� 68, Neuq��en Province, Zapala Department, 1 km S of Provincial Route 13 and 41 km W of Zapala, 38 �� 51 ' 14.4 ''S, 70 �� 30 ' 22.3 ''W, 1288 m., Published as part of Cristi��n S. Abdala, Diego Baldo, Ricardo A. Ju��rez & Robert E. Espinoza, 2016, The First Parthenogenetic Pleurodont Iguanian: A New All-female Liolaemus (Squamata: Liolaemidae) from Western Argentina, pp. 487-497 in Copeia 104 (2) on page 495, DOI: 10.1643/CH-15-381, http://zenodo.org/record/269580

Liolaemus senguer (FML 23679): KP 190039, Published as part of Cristi��n S. Abdala, Diego Baldo, Ricardo A. Ju��rez & Robert E. Espinoza, 2016, The First Parthenogenetic Pleurodont Iguanian: A New All-female Liolaemus (Squamata: Liolaemidae) from Western Argentina, pp. 487-497 in Copeia 104 (2) on page 495, DOI: 10.1643/CH-15-381, http://zenodo.org/record/269580

Liolaemus parthenos, new species urn:lsid:zoobank.org:act: 53 CC 2 C 59 - 2 E 4 D- 41 AA- 8804 - 462 B 90 ABAECC Figures 1–5; Table 1 Liolaemus boulengeri Cei (1973: 464, in part). Liolaemus boulengeri Cei and Roig (1976:71, 87, Map 5, in part). Liolaemus boulengeri Cei and Castro (1978:9, 21, Map 16, in part). Liolaemus boulengeri Cei (1986: 220–221, in part). Liolaemus boulengeri Schulte et al. (2000:79, 87; table 1; figs. 4–6). Liolaemus sp. nov. Morando et al. (2004: 845; table 1–3; figs. 2, 8). Liolaemus sp. Abdala and Díaz Gómez (2006: 29; fig. 3). Liolaemus sp. 3. Abdala (2007:51, 55, 57, 60, 77; figs. 32–36). Liolaemus cf. darwinii Pincheira-Donoso et al. (2007: 32; fig. 3). Liolaemus cf. darwinii Schulte (2013: 5; fig. 1). Liolaemus sp. 3 Olave et al. (2014: 329, 331; figs. 4, 6). Holotype.— FML 16221, adult female, Argentina, Mendoza Province, San Rafael Department, collected on the dunes next to El Nihuil Dam on Provincial Route 180, 35° 2 ' 19.77 ''S, 68 ° 40 ' 12.60 ''W, 1305 m, C. Abdala, J. Abdala, and E. Malovini, January 2001 (Fig. 1). Paratypes.— FML 16222 – 24, same data as holotype; IBAUNC 9772 –73, 9775– 77, Argentina, Mendoza Province, San Rafael Department, 10 to 60 km S of El Nihuil, 35 ° 7 ' 0.71 ''S, 68 ° 41 ' 4.28 ''W to 35 ° 33 ' 49.47 '' S, 68 ° 41 ' 15.14 ''W, 1400–1600 m, 25 November 1973; IBAUNC 11431 – 35, Argentina, Mendoza Province, San Rafael Department, Pampa del Diamante, 34 ° 54 ' 44.39 '' S, 68 ° 51 ' 38.58 ''W, 1400 m, 17 February 1975; MHNSR 78–82, Argentina, Mendoza Province, San Rafael Department, Club de Pescadores, El Nihuil, 35 ° 2 ' 10.54 ''S, 68 ° 42 ' 33.84 ''W, 1325 m, 1 January 1975. Diagnosis.— Liolaemus parthenos is the only known triploid unisexual iguanian lizard with the karyotype 3 n = 49 (19 M + 30m). The new species is a member of the L. boulengeri group (Etheridge, 1995; Abdala, 2007), with which it shares a femoral patch of enlarged scales on the posterior thigh. The L. boulengeri group includes the following subclades (Abdala, 2007): L. anomalus, L. darwinii, L. wiegmannii, and L. melanops (= L. telsen group + L. goetschi group), each of which includes several species as described below. Within the L. boulengeri group, L. parthenos is a member of the L. darwinii group (Abdala, 2007), with which it shares the following eight synapomorphies: (1) 14–18 dorsal head scales; (2) 24–28 gulars; (3) tail length/SVL ratio: 1.40–1.65; (4) femur length/ SVL ratio: 0.16–0.20; (5) 1–3 differentiated scales along the lower half of the anterior border of the external auditory meatus; (6) weakly developed longitudinal fold; (7) dark line passing vertically through superciliaries, eye, and subocular; and (8) small prescapular spots. Liolaemus parthenos can be distinguished from species in the L. anomalus group (L. acostai, L. anomalus, L. ditadai, L. lentus, L. millcayac, L. pipanaco, and L. pseudoanomalus) because the new species has a tail that is longer than its body, a head that is longer than wide, and lacks both a palpebral ‘‘comb’’ and pterygoid teeth. Liolaemus parthenos can be distinguished from species in the L. wiegmannii group (L. arambarensis, L. azarai, L. cuyumhue, L. lutzae, L. multimaculatus, L. occipitalis, L. rabinoi, L. riojanus, L. salinicola, L. scapularis, and L. wiegmannii) because the new species has a single row of lorilabials between the subocular and the supralabials (2–3 rows in members of the L. wiegmannii group) and four scales around the mental (6 scales in the L. wiegmannii group species). The new species, can be distinguished from species of the L. goetschi group (L. camarones, L. canqueli, L. casamiquelai, L. chehuachekenk, L. cuyanus, L. dumerili, L. fitzingerii, L. goetschi, L. mapuche, L. melanops, L. morenoi, L. puelche, L. rothi, L. sagei, L. shehuen, L. tromen, and L. xanthoviridis) based on its shorter SVL (maximum SVL 63.4 mm vs. 77–106 mm for the aforementioned taxa) and considerably less ventral melanism (except L. rothi and L. sagei). The new species also lacks the cephalic melanism typical of L. canqueli and L. melanops. With respect to L. casamiquelai, L. chehuachekenk, L. fitzingerii, L. morenoi, L. tromen, and L. xanthoviridis, the new species lacks the gular and antihumeral melanic collar that is typical of the aforementioned species. Liolaemus parthenos is distinct from L. cuyanus, L. goetschi, L. josei, L. mapuche, and L. puelche because the new species has four scales in contact with the mental, whereas L. cuyanus has six scales and L. goetschi, L. josei, L. mapuche, and L. puelche have from 4–6 scales in contact with the mental. The new species differs from L. donosobarrosi because the former has fewer scales around the midbody (mean = 57.1; range = 53–61 vs. mean = 85.4; range = 79–95, respectively). Also, the new species has a distinct dorsal pattern of quadrangular paravertebral markings, which distinguishes it from L. rothi, which has irregular markings that are not quadrangular. The new species also has pre- and postscapular spots that are not present in L. rothi. Liolaemus parthenos can be distinguished from species in the L. telsen group (L. boulengeri, L. hermannunezi, L. inacayali, L. loboi, L. martorii, L. purul, L. senguer, L. sitesi, and L. tehuelche) by its lack of gular melanism and dorsolateral bands that are more well defined. The new species differs from L. telsen because the former has less gular melanism, paravertebral markings are more well defined, well-defined dorsolateral bands, and fewer middorsal scales on the trunk (counted from occiput to anterior thigh: mean = 65; range = 61–68 vs. mean = 88.8; range = 83–96, respectively). The new species also differs from L. boulengeri, L. hermannunezi, L. loboi, L. martorii, L. purul, and L. tehuelche because the former has less conspicuous scapular spots. Within the L. darwinii group, L. parthenos is the only species with strongly cuspidate coronas and distally expanded cheek teeth, as well as a unique color pattern for the group. The new species can be further distinguished from members of the L. darwinii group (L. abaucan, L. albiceps, L. calchaqui, L. chacoensis, L. cinereus, L. crepuscularis, L. darwinii, L. diaguita, L. espinozai, L. grosseorum, L. irregularis, L. koslowskyi, L. laurenti, L. lavillai, L. montanezi, L. olongasta, L. ornatus, L. pacha, L. quilmes, and L. uspallatensis) because L. parthenos has a unique pattern of large dark brown or black quadrangular or subquadrangular paravertebral and lateral markings, white dorsolateral stripes, and a white abdomen with small dark spots. Liolaemus parthenos can be further distinguished from L. albiceps, L. calchaqui, L. crepuscularis, L. irregularis, L. lavillai, and L. ornatus because females of the latter three species possess precloacal pores and adult L. albiceps and L. irregularis are considerably larger than L. parthenos (L. parthenos: maximum SVL 63.4 mm vs. 82.5–86.1 mm, respectively). Finally, L. parthenos can be differentiated from L. darwinii because the new species lacks an antehumeral arch and abdominal and femoral melanism. Description of holotype.— Adult female (Fig. 1). SVL: 59.8 mm. Tail complete, not regenerated: 92.7 mm. Rostral surrounded by 6 scales. Nasal dorsolateral in orientation. Supraoculars: 8. Interparietal smaller than parietals. Lorilabials: 7. Supralabials: 8. Mental surrounded by 4 scales. Infralabials: 5. Temporals: 8, not keeled. Posterior teeth with expanded cusps. Anterior border of auditory meatus with one differentiated scale. Snout blunt in lateral view. Midbody scales: 58. Dorsal scales: 68 from occiput to anterior thigh, laminar, imbricate, and keeled. Lateral neck folds well developed. Gulars: 27. Ventrals: in 21 rows, imbricate, same size as dorsals. Infratarsals and infracarpals imbricate and trifid. Femoral patch well developed. No precloacal pores. Head light brown with two rows of quadrangular dark brown paravertebral marks with white posterior margins. Background of vertebral region dark brown with four lateral markings of same color. Anterior and posterior limbs same color as dorsum. Ventrally, throat variegated with dark brown or black spots; spot density increases posteriorly toward chest, abdomen, limbs, and tail. Measurements of holotype.— Head 1.2 times longer (11.9 mm) than wide (9.6 mm). Head height: 8.2 mm. Eye diameter: 2.9 mm. Subocular: 3.7 mm. Auditory meatus height: 2.2 mm; width: 1.8 mm. Torso length: 26.8 mm; width: 12.9 mm. Thigh length: 9.9 mm. Upper arm length: 8.2 mm; width: 2.1 mm. Forearm length: 8.3 mm. Hand length: 9.2 mm. Tail length: 92.7 mm. Variation.— Data from 70 females, unless otherwise noted. Mental in contact with four scales. Infralabials: 5–6. Lorilabials: 6–7, in one row. Interparietal smaller than parietal. Temporals: 8–12. Auditory meatus with 1–3 scales on anterior edge and 0–2 on posterior edge. Neck folds well developed. Gulars: 23–28. Head narrow, longer (mean = 12.1 mm) than wide (mean = 9.4 mm). Neck narrower than head and trunk. Body slender, SVL 36.1–63.4 mm (mean = 56.7 mm). Scales around midbody: 53–61 (mean = 57.1). Dorsal scales between occiput and anterior thigh: 61–68 (mean = 65.0). Dorsal scales laminar, keeled, and imbricate. Infratarsals and infracarpals with imbricate, trifid scales. Femoral patch with 23–30 cone-shaped, mucronate scales. Ventrals: 91–105 (mean = 97.6), larger than dorsals. Precloacal pores absent. Complete tail: 64.3–92.7 mm long (n = 48; mean = 83.3 mm); 1.4–1.6 times longer than SVL. Color variation in life.— Dorsal head light brown or gray with small black, irregularly distributed scales. Background dorsal color of body usually light brown, but light gray specimens not uncommon. Paravertebral markings square or rectangular, arranged longitudinally to long axis of body and dark brown or dark gray with white posterior margins. Lateral markings same color and form as paravertebral markings, but smaller than paravertebrals in some specimens. Vertebral region dark gray or light brown. Prescapular or postscapular spots less well defined, generally darker than lateral markings, but sometimes indistinguishable from them. Throat, abdomen, and cloaca region white with small irregularly shaped black spots. Ventral spots usually most dense along sides of abdomen. Mental and shield scales usually dark brown, but occasionally dark green. Longitudinal line extending along lateral tail (25–50 % total tail length) splits into small black or dark brown rectangular bars. Color becomes less vibrant, but otherwise does not change appreciably after> 6 mo in preservative (70 % ethanol). Fig. 5. Etymology.— The specific epithet parthenos is a Greek noun meaning ‘‘virgin’’ or ‘‘maiden,’’ in reference to the presumed reproductive strategy of this all-female species. Distribution.— Liolaemus parthenos is known only from the outskirts of El Nihuil, Salinas del Diamante, and from south of El Nihuil on Provincial Route 180 near Sierra El Nevado, San Rafael Department, Mendoza Province, Argentina (1305– 1600 m; Fig. 2). Natural history.— Liolaemus parthenos is apparently an allfemale parthenogenetic species. Despite 24 collecting expeditions since 1995 for a total of approximately 650 combined person hours of observing and collecting this species in nature, and after examining more than 300 specimens (note only 65 specimens were collected and preserved because of restrictions imposed by collecting permits), no males were encountered. Thus, the probability of not encountering a male, if this was a bisexual species with an equal population sex ratio, would be 0.5 65 or 2.7 20, an infinitesimally small likelihood. Field observations of active L. parthenos were made from October through February, and again in April. During summer months (December to February), lizards were active only in the morning and afternoon. The shift to bimodal activity apparently helps them avoid the extreme heat of midday. In April (fall), only juveniles were active at midday, indicating seasonal or ontogenetic variation in diel activity. Body temperatures (T bs) from four adult L. parthenos (SVL = 51.8 ± 3.4 mm) collected in the late afternoon of 11 February 1995 along the sandy shore of El Nihuil reservoir averaged 34.6 ± 3.4 °C, which is similar to the field T bs reported for other low-elevation Liolaemus lizards (Espinoza et al., 2004). Liolaemus parthenos is oviparous and reproduces in summer. Reproductively active females (well-developed eggs in oviducts) were observed in January (n = 5), and nonreproductive females were found in December and February (n = 13). However, in a different year, we found females with oviducts full of developing eggs in December (n = 11). These observations suggest that the reproductive period begins in November and lasts until late January. Liolaemus parthenos is sympatric with the lizards Aurivela longicauda (Teiidae), Diplolaemus sexcinctus and Leiosaurus bellii (Leiosauridae), and two congeneric species: L. gracilis and L. grosseorum. Several species of snakes, which are potential predators of the new species, have also been observed in the area: the dipsadine colubrid snakes Oxyrhopus rhombifer, Philodryas trilineata, and Xenodon semicinctus, as well as the viperid Bothrops ammodytoides. Cytogenetic analysis.— Liolaemus parthenos has a triploid karyotype with 3 n = 49 chromosomes (19 macrochromosomes + 30 microchromosomes): 17 of the macrochromosomes are biarmed metacentric or submetacentric and two are acrocentric. All the microchromosomes appear to be acro- or telocentric (Fig. 3). Because of their size and morphology, the macrochromosomes clustered into four groups: (1) the two largest pairs almost equal in size, but differing in centromere position (the first metacentric and the second submetacentric); (2) pairs 3 and 4 almost equal in size and morphology (with a centric fission in the haploid homologue of pair 3); (3) pair 5 (submetacentric in two homologues and metacentric in the third); and (4) pair 6, the smallest of the macrochromosomes with metacentric morphology. Only two of the homologous regions of chromosome pair 2 show secondary constrictions and areas with NORs in the telomere of their long arms. Phylogenetic analysis.— The trees based on Bayesian inference and maximum parsimony were topologically very similar, with sources of conflict occurring solely at nodes that were weakly supported in one or both analyses (Fig. 4). With respect to the new species, both trees strongly supported the placement of L. parthenos in the L. grosseorum clade of the L. boulengeri group: L. boulengeri group (L. chacoensis group (L. laurenti group (L. darwinii group (L. grosseorum clade)))) (Fig. 4). The L. grosseorum clade is also supported by nine morphological synapomorphies (Abdala, 2007). Within the L. grosseorum clade, L. parthenos is in a well-supported yet unresolved clade with L. darwinii (Río Negro Province) and L. laurenti (Fig. 4 A) or nested within a weakly supported clade containing populations of L. darwinii from the more southern provinces of Mendoza and Ŕıo Negro and those occurring farther north in La Rioja Province, with L. laurenti strongly supported as sister to these four lineages (Fig. 4 B). DISCUSSION Based on previous studies (Schulte et al., 2000; Morando et al., 2004; Pincheira-Donoso et al., 2007; Schulte, 2013) and the phylogenetic hypotheses presented here (Fig. 4), L. parthenos is closely related to L. darwinii and L. laurenti, species that are morphologically typical of the L. darwinii group (Etheridge, 1993; Abdala, 2007). The closest known locality for L. laurenti is approximately 300 km to the north of the type locality of L. parthenos, whereas L. darwinii has a much wider distribution (Abdala, 2007) including a small population that is sympatric with L. parthenos at the type locality of the latter species. It is noteworthy that a similarly proximate distributional association has been reported for a parthenogenetic species of Leiolepis and its matrilineal ancestor (Grismer and Grismer, 2010; Grismer et al., 2014). A close phylogenetic association between L. parthenos and L. darwinii has been reported in previous phylogenetic analyses based on mtDNA. Schulte et al. (2000) recovered L. parthenos (as ‘‘ L. boulengeri ’’) in the clade: L. grosseorum (L. darwinii (L. parthenos (L. laurenti))). A phylogeographic analysis of the L. darwinii group conducted by Morando et al. (2004) recovered L. parthenos (as ‘‘ L. sp. nov.’’) as the sister taxon to L. laurenti + L. darwinii. Finally, Pincheira-Donoso et al. (2007) recovered L. parthenos (as L. cf. darwinii; SDSU 3469, AF099275) as the sister taxon to L. darwinii in the clade (L. grosseorum (L. darwinii (L. parthenos + L. darwinii from Chubut))). Although L. parthenos is superficially similar to L. boulengeri, these three molecular studies each strongly support the relationships among L. parthenos, L. darwinii, L. laurenti, and L. grosseorum. The most parsimonious interpretation of the triploid karyotype of L. parthenos (Fig. 5) is that the species arose via hybridization. The karyotype of L. parthenos (Fig. 4) has a clear diploid component (12 M + 20m) contributed by one parental species and an additional haploid set (7 M + 10m) provided by the other parental genome (Fig. 5). In the haploid component the two acrocentric macrochromosomes are interpreted as homologs of the two arms (3 p and 3 q) of pair 3 (3 a) in the 2 n set. The 30 microchromosomes of L. parthenos are best interpret

Liolaemus espinozai (MCN 213): KP 190034, Published as part of Cristi��n S. Abdala, Diego Baldo, Ricardo A. Ju��rez & Robert E. Espinoza, 2016, The First Parthenogenetic Pleurodont Iguanian: A New All-female Liolaemus (Squamata: Liolaemidae) from Western Argentina, pp. 487-497 in Copeia 104 (2) on page 495, DOI: 10.1643/CH-15-381, http://zenodo.org/record/269580

Liolaemus goetschi (n = 20): FML 21501 ���07, 21511, MPCN 57��� 65, Ŕıo Negro Province, General Roca Department, Laguna Playa, ca. 20 km N of General Roca, 30 �� 52 ' 59 ''S, 67 �� 34 '0 8 ''W; FML 21508, Ŕıo Negro Province, General Roca Department, 20 km S of Catriel on National Route 151; FML 21509 ��� 10, Ŕıo Negro Province, General Roca Department, 50 km S of Catriel, on National Route 151., Published as part of Cristi��n S. Abdala, Diego Baldo, Ricardo A. Ju��rez & Robert E. Espinoza, 2016, The First Parthenogenetic Pleurodont Iguanian: A New All-female Liolaemus (Squamata: Liolaemidae) from Western Argentina, pp. 487-497 in Copeia 104 (2) on page 494, DOI: 10.1643/CH-15-381, http://zenodo.org/record/269580

Liolaemus morenoi (n = 14): FML 17020 ��� 28, Neuq��en Province, Collon Cur�� Department, 2 km N of Cerrito Pĩnon; FML 22206 ��� 10, Neuq��en Province, Zapala Department, 20 km SW to Zapala on National Route 40., Published as part of Cristi��n S. Abdala, Diego Baldo, Ricardo A. Ju��rez & Robert E. Espinoza, 2016, The First Parthenogenetic Pleurodont Iguanian: A New All-female Liolaemus (Squamata: Liolaemidae) from Western Argentina, pp. 487-497 in Copeia 104 (2) on page 494, DOI: 10.1643/CH-15-381, http://zenodo.org/record/269580

Liolaemus lutzae (n = 7): FML 1287, Brazil, Rio de Janeiro Province, Cabo Frio., Published as part of Cristi��n S. Abdala, Diego Baldo, Ricardo A. Ju��rez & Robert E. Espinoza, 2016, The First Parthenogenetic Pleurodont Iguanian: A New All-female Liolaemus (Squamata: Liolaemidae) from Western Argentina, pp. 487-497 in Copeia 104 (2) on page 494, DOI: 10.1643/CH-15-381, http://zenodo.org/record/269580

Liolaemus occipitalis (n = 9): FML 1288 ���89, 2618��� 20, Brazil, Rio Grande do Sul Province, Tramandai., Published as part of Cristi��n S. Abdala, Diego Baldo, Ricardo A. Ju��rez & Robert E. Espinoza, 2016, The First Parthenogenetic Pleurodont Iguanian: A New All-female Liolaemus (Squamata: Liolaemidae) from Western Argentina, pp. 487-497 in Copeia 104 (2) on page 494, DOI: 10.1643/CH-15-381, http://zenodo.org/record/269580

(1) We measured thermal tolerances (critical thermal minimum, C T min and panting threshold, T pant ) for four populations of Homonota darwinii spanning most of the latitudinal range of the species. (2) C T min differed across populations, but not latitudinally as predicted, likely because latitude was not as good a proxy for operative temperatures ( T e ). (3) Some populations had subzero C T min indicating supercooling or freeze tolerance—the first time either phenomenon has been reported for a gecko. (4) T pant did not differ significantly among populations. (5) The thermal tolerance breadth appears to be correlated with thermal variability in the environment. (6) Annual T e data indicate gecko retreats play a crucial role in surviving extreme surface temperatures ( 50 °C).

Herbivory is generally thought to be restricted to reptiles with large body sizes that live in warm climates. We show that Liolaemus poecilochromus is primarily herbivorous (>80 plants in diet) even as juveniles, making them the smallest herbivorous reptile known. We detected relatively few differences in diet between the sexes, despite male-biased sexual dimorphism in head and body size. Adults consumed more mites and flowers than juveniles, and we detected a weak ontogenetic shift from omnivory to herbivory that is attributable to the lower volumetric consumption of plants by juvenile males. We discuss the abiotic and biotic conditions that likely selected for herbivory in this and other small-bodied, high-elevation Liolaemus. Herbivoría en general se cree que se limita a los reptiles con cuerpos grandes que viven en climas cálidos. Mostramos que Liolaemus poecilochromus es principalmente herbívora (>80% de plantas en la dieta) incluso los juveniles, convirtiéndolo por esto en el reptil herbívoro más pequeño conocido. Asimismo, detectamos pocas diferencias en la dieta entre los sexos, a pesar del dimorfismo sexual a favor de los machos en el tamaño de la cabeza y el cuerpo. Los adultos consumen más ácaros y flores que los juveniles, por otro lado se detectó un cambio ontogenético débil de omnivoria a herbivoría en los machos juveniles, debido a su bajo consumo de plantas. Discutimos las condiciones abióticas y bióticas que probablemente favorecieron la herbivoría en este y otros Liolaemus de cuerpo pequeño y alta elevación Fil: Valdecantos, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina Fil: Arias, Federico José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina Fil: Espinoza, Robert E.. California State University; Estados Unidos

We describe a new species of Phymaturus from the Sierra La Invernada of San Juan Province, Argentina. The new species shares the apomorphies of the P. palluma group including a fragmented subocular, square nonimbricate superciliaries, rugose and strongly mucronate dorsal caudals, and a midvertebral band of enlarged scales. Within the P. palluma group, the new species can be assigned to the Puna clade, with which it shares a dorsal pattern of small, dispersed brown spots and lack of black reticulations. The new species differs from other members of the Puna clade in several aspects of squamation and body pattern and color. Most notably, the new Phymaturus has a conspicuous yellow scapular spot, lacks a vertebral stripe, and has incomplete dark pigmentation over the dorsal neck. The new species is known only from the region of the type locality, the southernmost (and geographically isolated) extent of the Puna phytogeographic province, where it occurs at high elevations (>3100 m). We provide information on ...

A phylogenetic taxonomy of species in theCyrtodactylus peguensisgroup from the Ayeyarwady Basin of Myanmar is constructed based on color pattern, morphology, and molecular systematic analyses using the mitochondrial gene NADH dehydrogenase subunit 2. Newly collected samples from the type locality ofC. peguensisand other localities indicate that this clade is endemic to central Myanmar and contains at least seven species, four of which are undescribed. Three species, includingC. peguensisoccur in the low hills of the Bago Yoma Range within the central portion of the Ayeyarwady Basin. Two of these,C. myintkyawthuraisp. nov. from the northern and central Bago Yoma andC. meersisp. nov. which is syntopic withC. peguensisin the southern Bago Yoma are described herein. As more lowland hilly areas bordering, and within the Ayeyarwady Basin are surveyed, more new species of this group are likely to be discovered. These discoveries continue the recent surge of descriptions of new species ofCyrtodactylusthat are being discovered in Myanmar.

We describe two new species of Liolaemus belonging to the montanus series. The new species are closely related to L. dorbignyi, but are disjunctly distributed with respect to this taxon. Both new species exhibit unique color patterns, which, along with differences in squamation, differentiate the two new taxa from the other species in the series. Both new species are saxicolous and inhabit rocky hills in the Puna regions of northwestern Argentina. One occurs in the Cerro de la Virgen, Nevados de Cachi and Nevados de Palermo of Salta Province. The other is known only from its type locality in the Cerro El Pichao of Tucuman Province.

R ICHARD EMMETT ETHERIDGE is a Professor Emeritus of Biology at San Diego State University whose career as a herpetologist has spanned more than sixty years. As a consequence, his biography reads like a who’s who of twentieth century herpetology. Although best known for his highly influential research in lizard systematics, Richard is also a former boy snaker, Navy sonarman, accomplished mentor, Zen practitioner, world traveler, birdwatcher, and chocolate aficionado. Richard was born on 16 September 1929 in Houston, Texas, the first child of Ethel Agatha Hans and Jerry Haller Etheridge. Richard’s father was born in Dallas, Texas, and joined the Merchant Marines after leaving high school. During the Great Depression, he worked for the Ford Motor Company and eventually owned his own automobile parts and repair company. Richard’s mother was born in southern Texas; she married Richard’s father not long after graduating high school and became a homemaker. Richard’s only sibling, Jerry Haller Etheridge, Jr. (deceased), was a Professor of Music at the University of Georgia, Atlanta. Like their parents, Richard and Jerry were raised in Houston. Richard’s childhood was unhampered by parental expectations; he and his brother were encouraged to pursue whatever careers they wished. As is the case for many herpetologists, Richard can trace his interests in amphibians and reptiles to a specific event that occurred early in his life. In 1944, at the age of 15, Richard had his first encounter with a snake. As recounted in his words, this would prove to be a life-defining moment.

Many of the threats to the persistence of populations of sensitive species have physiological or pathological mechanisms, and those mechanisms are best understood through the inherently integrative discipline of physiological ecology. The desert tortoise was listed under the Endangered Species Act largely due to a newly recognized upper respiratory disease thought to cause mortality in individuals and severe declines in populations. Numerous hypotheses about the threats to the persistence of desert tortoise populations involve acquisition of nutrients, and its connection to stress and disease. The nutritional wisdom hypothesis posits that animals should forage not for particular food items, but instead, for particular nutrients such as calcium and phosphorus used in building bones. The optimal foraging hypothesis suggests that, in circumstances of resource abundance, tortoises should forage as dietary specialists as a means of maximizing intake of resources. The optimal digestion hypothesis suggests that tortoises should process ingesta in ways that regulate assimilation rate. Finally, the cost-of-switching hypothesis suggests that herbivores, like the desert tortoise, should avoid switching food types to avoid negatively affecting the microbe community responsible for fermenting plants into energy and nutrients. Combining hypotheses into a resource acquisition theory leads to novel predictions that are generally supported by data presented here. Testing hypotheses, and synthesizing test results into a theory, provides a robust scientific alternative to the popular use of untested hypotheses and unanalyzed data to assert the needs of species. The scientific approach should focus on hypotheses concerning anthropogenic modifications of the environment that impact physiological processes ultimately important to population phenomena. We show how measurements of such impacts as nutrient starvation, can cause physiological stress, and that the endocrine mechanisms involved with stress can result in disease. Finally, our new syntheses evince a new hypothesis. Free molecules of the stress hormone corticosterone can inhibit immunity, and the abundance of "free corticosterone" in the blood (thought to be the active form of the hormone) is regulated when the corticosterone molecules combine with binding globulins. The sex hormone, testosterone, combines with the same binding globulin. High levels of testosterone, naturally occurring in the breeding season, may be further enhanced in populations at high densities, and the resulting excess testosterone may compete with binding globulins, thereby releasing corticosterone and reducing immunity to disease. This sequence could result in physiological and pathological phenomena leading to population cycles with a period that would be essentially impossible to observe in desert tortoise. Such cycles could obscure population fluctuations of anthropogenic origin.

Aggregating has been widely studied in a variety of animals and found to have important benefits in terms of sociality, courtship, predator avoidance and physiology. Several species of nocturnal geckos form diurnal aggregations; however, little is known about the benefits of these groupings. We conducted a series of experiments to determine the benefit of aggregation for the desert-dwelling western banded gecko, Coleonyx variegatus. We found that banded geckos benefit from aggregation by a reduction in evaporative water loss (EWL). No social or mating benefits were detected, and geckos did not group to avoid predators. Geckos did not select diurnal retreat sites based solely on the scent of conspecifics, although they aggregated readily when conspecifics were present. Thus, C. variegatus appear to achieve physiological but not social benefits from grouping. Banded geckos belong to an ancestrally tropical lineage whose descendants invaded present-day North American deserts at a time when these regions were more mesic. This may explain their relatively high rate of EWL. Aggregating seems to be a solution to this physiological handicap. Our study also suggests a path for the evolution of social behaviour: as animals aggregate for physiological benefits, the stage is set for the evolution of more complex social interactions.

We tested for the occurrence of Bergmann's rule, the pattern of increasing body size with latitude, and Rapoport's rule, the positive relationship between geographical range size and latitude, in 34 lineages of Liolaemus lizards that occupy arid regions of the Andean foothills. We tested the climatic-variability hypothesis (CVH) by examining the relationship between thermal tolerance breadth and distribution. Each of these analyses was performed varying the level of phylogenetic inclusiveness. Bergmann's rule and the CVH were supported, but Rapoport's rule was not. More variance in the data for Bergmann's rule and the CVH was explained using species belonging to the L. boulengeri series rather than all species, and inclusion of multiple outgroups tended to obscure these macroecological patterns. Evidence for Bergmann's rule and the predicted patterns from the CVH remained after application of phylogenetic comparative methods, indicating a greater role of ecological processes rather than phylogeny in shaping the current species distributions of these lizards.

Animals that are unable to meet their metabolic needs should adopt compensatory behaviors to mitigate their energetic deficits. Voluntary hypothermia is one such energy-saving strategy. Physiological constraints associated with the digestion of plant tissues, however, may limit the thermoregulatory options of herbivorous ectotherms. In this laboratory study, selected body temperatures of Desert Iguanas (Dipsosaurus dorsalis), subjected to two different rations of a carnivorous and a herbivorous diet, were measured in a laboratory thermal gradient. Lizards fed a carnivorous diet and rationed to 50% of their daily energetic requirement selected significantly lower body temperatures than did lizards in the other diet/ration treatments. Lizards fed a herbivorous diet selected higher body temperatures than did the same lizards fed a carnivorous diet regardless of ration. Our study indicates that selected temperatures are influenced by both diet quality and quantity. These results support the hypothesis that herbivorous reptiles require elevated body temperatures to digest plant tissues. Our findings do not fully support the behavioral hypothermia hypothesis, which posits that diurnal lizards will seek cool temperatures at night to reduce their energy expenditure. Thermoregulatory strategies of Desert Iguanas and other herbivorous lizards may be influenced by the need to balance high body temperatures to digest plant material with the high metabolic costs of maintaining high temperatures.

The Liolaemus elongatus group currently includes eight species (including the species described herein) of mid-sized, long-tailed, primarily saxicolous lizards. Members of this lineage are distributed in northwestern Argentina along the Andean Cordillera south to the Patagonian Steppe (27–44° S) and over a wide range of elevations (350–3900 m). Here we describe two new species belonging to the northern radiation of the elongatus group. The four currently recognized members of this northern subclade (including the two species described herein) have fewer midbody scales than other members of the elongatus group, brown to black heads, and lack the distinct dorsal body or tail patterns found in adults of other species belonging to the elongatus group. Additionally, pregnant and recently spent females exhibit crimson red color in the cloacal region—a trait known only for members of this northern lineage and L. buergeri. The first new species, L. dicktracyi from the Sierra de Famatina of La Rioja Province, diff...

We examined responses of three iguanian lizards, the phrynosomatid Sceloporus poinsettii and the tropidurids Tropidurus hispidus and Phymaturus punae, to prey chemicals and plant chemicals. When chemical stimuli were presented on cotton swabs or on ceramic tiles, neither S. poinsettii nor T. hispidus discriminated among prey, plant, and control stimuli. In contrast, an individual of P. punae discriminated both prey and plant chemicals from control stimuli in swab tests, typically biting swabs bearing prey or plant cues. These findings are consistent with the hypothesis that plant chemical discrimination evolves in herbivorous iguanians such as P. punae. Sceloporus poinsettii, which appears to be entirely insectivorous at some times, but eats substantial quantities of flowers at others, did not discriminate among the stimuli. Because all previously tested herbivores and omnivores responded strongly to prey and plant chemicals, the absence of such discriminations by S. poinsettii raises questions about the degree and regularity of herbivory that may be required for plant chemical discrimination to evolve. The results extend the absence of prey chemical discrimination in ambush foragers to T. hispidus.

Phylogenetic relationships within the iguanid lizard genus Liolaemus are investigated using 1710 aligned base positions (785 phylogenetically informative) of mitochondrial DNA sequences, representing coding regions for eight tRNAs, ND2, and portions of ND1 and COL Sixty new sequences ranging in length from 1736 to 1754 bases are compared with four previously reported sequences. Liolaemus species form two well-supported monophyletic groups of subgeneric status, Liolaemus and Eulaemus. These subgenera appear to have separated at least 12.6 million years ago based on the amount of molecular evolutionary divergence between them. Hypotheses that species occurring in the Andes, west of the Andes, and east of the Andes, each comprise distinct monophyletic groups are independently rejected statistically. The shortest estimate of phylogeny suggests mat Liolaemus originated either in the Andes or the eastern lowlands. Numerous evolutionary shifts have occurred between the Andes, and the eastern and western lowlands, suggesting recurring vicariance and dispersal. Species occurring at high elevations or high latitudes usually have viviparous reproduction. Depending on whether parity mode is considered reversible in Liolaemus, the most parsimonious reconstruction supports at least six independent origins of viviparity or at least three gains followed by three losses of viviparity among die 60 Liolaemus lineages examined.

Diet quality can influence many aspects of digestion, but the links between diet quality and resting metabolism are poorly understood. In nature, it might be beneficial to reduce energy expenditure when only poor quality diets are available. Alternatively, animals might increase the processing capacity of the gut to more thoroughly extract energy. If maintaining the processing capacity of the gut is energetically expensive, then increasing gut size or function might result in higher resting metabolism. In ectotherms, most digestive functions are temperature dependent, thus another strategy to maintain energy balance might be to alter selected body temperatures. We tested whether differing concentrations of dietary fiber affected the resting metabolic rate or body temperatures selected by chuckwallas (Sauromalus obesus) – lizards that naturally experience marked variation in dietary fiber. Resting metabolic rates measured at two temperatures and over three time intervals did not differ between groups of lizards force-fed low- (30% neutral-detergent fiber; NDF) and high-fiber (45% NDF) diets, nor did these diet differences influence body temperatures selected in a thermal gradient. We conclude that ecologically relevant differences in diet quality may have negligible effects on resting metabolic rates and body temperatures selected by chuckwallas.

MB and MR were funded by a grant from the Esmee Fairbairn Foundation, BC by the Rufford Foundation. North American and Mexican species assessments were funded by the Regina Bauer Frankenberg Foundation for Animal Welfare. Species assessments under the Global Reptile Assessment (GRA) initiative are supported by: Moore Family Foundation, Gordon and Betty Moore Foundation, Conservation International, Critical Ecosystem Partnership Fund (CEPF), and European Commission. Additional acknowledgements are included in the online supplementary material. The assessment workshop for Mexican reptiles was kindly hosted by Ricardo Ayala and the station personnel of the Estacion de Biologia Chamela, Institut de Biologia, Universidad Nacional Autonoma de Mexico. Workshop and logistical organisation of the Philippines assessments was provided by the Conservation International Philippines Office, in particular Ruth Grace Rose Ambal, Melizar V. Duya and Oliver Coroza. Workshop and logistical organisation for the European Reptile and Amphibian Assessments was provided by Doga Dernegi, in particular Ozge Balkiz and Ozgur Koc. Workshop and logistical organisation for assessments of sea snakes and homalopsids was provided by the International Sea Turtle Symposium and Dr. Colin Limpus (Australian Government Environmental Protection Agency). Special thanks to Jenny Chapman (EPA) and Chloe Schaub le (ISTS). Thank you also to Dr. Gordon Guymer (Chief Botanist Director of Herbarium) for accommodating us at the Herbarium in the Brisbane Botanical Gardens, and Mark Read and Kirsten Dobbs (Great Barrier Reef Marine Parks Association) and Dave Pollard and Brad Warren (Ocean Watch Australia) for institutional support. Mohamed Bin Zayed Species Conservation Fund, Conservation International Madagascar and the Darwin Initiative contributed to funding the costs of the Madagascar reptile workshop., Effective and targeted conservation action requires detailed information about species, their distribution, systematics and ecology as well as the distribution of threat processes which affect them. Knowledge of reptilian diversity remains surprisingly disparate, and innovative means of gaining rapid insight into the status of reptiles are needed in order to highlight urgent conservation cases and inform environmental policy with appropriate biodiversity information in a timely manner. We present the first ever global analysis of extinction risk in reptiles, based on a random representative sample of 1500 species (16% of all currently known species). To our knowledge, our results provide the first analysis of the global conservation status and distribution patterns of reptiles and the threats affecting them, highlighting conservation priorities and knowledge gaps which need to be addressed urgently to ensure the continued survival of the world’s reptiles. Nearly one in five reptilian species are threatened with extinction, with another one in five species classed as Data Deficient. The proportion of threatened reptile species is highest in freshwater environments, tropical regions and on oceanic islands, while data deficiency was highest in tropical areas, such as Central Africa and Southeast Asia, and among fossorial reptiles. Our results emphasise the need for research attention to be focussed on tropical areas which are experiencing the most dramatic rates of habitat loss, on fossorial reptiles for which there is a chronic lack of data, and on certain taxa such as snakes for which extinction risk may currently be underestimated due to lack of population information. Conservation actions specifically need to mitigate the effects of human-induced habitat loss and harvesting, which are the predominant threats to reptiles., Esmee Fairbairn Foundation, Rufford Foundation, Regina Bauer Frankenberg Foundation for Animal Welfare, Moore Family Foundation, Gordon and Betty Moore Foundation, Conservation International, Critical Ecosystem Partnership Fund (CEPF), European Commission Joint Research Centre, Zayed Species Conservation Fund, Conservation International Madagascar, Darwin Initiative

Núñez (2004) examined the syntypes of Liolaemus pictus major Boulenger in the British Museum of Natural History and concluded, without supporting data, that this taxon is a senior synonym of Liolaemus capillitas Hulse. We show that the evidence does not support Núñez’s (2004) proposal. We first document the complex taxonomic history of L. p. major, the lack of a precise or even definitive type locality, and the implications of the latter on subsequent checklists and research. Second, we note differences between Boulenger’s (1885) type description of L. p. major and Hulse’s (1979) type description of L. capillitas. Third, we show that the syntypes of L. p. major photographed by Núñez (2004) do not exhibit the character states of L. capillitas. We conclude that L. capillitas is not a synonym of L. p. major. Based on the available evidence, the syntypes of L. p. major are probably assignable to Liolaemus elongatus from populations occurring in Patagonia (southern Argentina or adjacent Chile). However, the precise identity of the syntypes requires additional study and perhaps a type locality restriction or redefinition of L. elongatus, which is itself in a state of flux. Núñez (2004) examinó los sintipos de Liolaemus pictus major Boulenger en el Museo Británico de Historia Naturale y concluyó, sin datos que lo sostengan, que este taxón es un sinónimo señor de Liolaemus capillitas Hulse. Nosotros mostramos que la evidencia disponible no apoya la propuesta de Núñez (2004). Primero documentamos la compleja historia de L. p. major, la carencia de una localidad tipo o la restricción de una, y las implicancias de esto último en subsecuentes checklists e investigaciones. Segundo, notamos diferencias entre la descripción tipo de Boulenger (1885) de L. p. major y la descripción tipo de L. capillitas de Hulse (1979). Tercero, mostramos que los sintipos de L. p. major fotografiados por Núñez (2004) no exhiben los caracteres presentes en L. capillitas. Concluimos que L. capillitas no es un sinónimo L. p. major. Basados en la evidencia disponible, los sintipos de L. p. major son aparentemente asignables a Liolaemus elongatus de poblaciones que se encuentran en la Patagonia (sur de Argentina o adyacentes en Chile). De todos modos, la identidad precisa de los sintipos requerirá de estudio adicional y quizás la restricción de una localidad o la redefinición de L. elongatus, especie que por sí misma se encuentra pobremente definida. Fil: Espinoza, Robert E.. California State University; Estados Unidos Fil: Lobo Gaviola, Fernando Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Bio y Geociencias del Noroeste Argentino; Argentina; Argentina. Universidad Nacional de Salta. Facultad de Cs.naturales. Catedra de Anatomia Comparada; Argentina Fil: Etheridge, Richard. San Diego State University; Estados Unidos

We tested the thermal benefits of aggregation ("knotting") for a high-elevation (>4300 m) population of metamorphic Rhinella spinulosa. Fewer knots were recorded when the sun was low on the horizon and aggregating toads dispersed under cloudy skies or when experimentally shaded. Body temperatures of sun-exposed toads averaged 2.3 °C higher when in knots than when solitary. Proximity to water and similarity in body size between aggregating and solitary toads suggest that grouping is not imposed by a need for reducing evaporative water loss. Aggregation apparently provides thermal benefits, which should translate into faster growth. Fil: Espinoza, Robert E.. California State University; Estados Unidos Fil: Quinteros, Andres Sebastian. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Cátedra de Anatomia Comparada; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentina

We provide descriptions for two new cryptic species belonging to the Liolaemus alticolor group from northern Argentina and northeastern Chile. The new species were previously considered conspecific with either Liolaemus walkeri in northeastern Chile or L. alticolor in northwestern Argentina and adjacent Chile. However, the new species differ from these taxa, and all other members of the alticolor group, in a number of characteristics. Liolaemus chaltin n. sp. differs from L. alticolor from the type locality (Tiahuanaco, Bolivia) in the following ways: this new species has a larger body size; a fragmented vertebral stripe; and a pigmented subocular (white in L. alticolor), and is one of just three members of the alticolor group that is oviparous. Liolaemus puna n. sp. differs from all other members of the alticolor group in that male L. puna lack paravertebral markings and dorsolateral and vertebral stripes. Females, however, are similar to other members of the alticolor group but can be distinguished from them by several meristic characters. Liolaemus puna is widely distributed throughout the high-elevation (3680-4400 m) Puna regions (a flat or gently sloping steppe dominated by perennial bunch grasses and small shrubs) in northwestern Argentina and northeastern Chile. Liolaemus chaltin is known only from the Puna of central Jujuy Province, Argentina (3400-3750 m). Based on examinations of the type series of L. alticolor and L. walkeri, we determined that virtually all northern Chilean populations of Liolaemus previously considered to belong to either of these two species should be assigned to L. puna. Thus, the range of L. alticolor is restricted to Bolivia and southern Perú, and the range of L. walkeri is restricted to central and southern Andean Perú. Liolaemus chaltin is oviparous, and L. puna is viviparous, and because both are morphologically similar to L. alticolor, some investigators have suggested that some populations of L. alticolor may be reproductive bimodal. Our studies, however, indicate that these populations represent sympatric populations of the cryptic species described herein. A diagnostic key is provided for the currently recognized members of the alticolor group. Fil: Lobo Gaviola, Fernando Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina Fil: Espinoza, Robert. Universidad Nacional de Salta; Argentina

Herbivory has evolved in many groups of vertebrates, but it is rare among both extinct and extant nonavian reptiles. Among squamate reptiles, (lizards, snakes, and their relatives), 7,800 species are considered to be herbivorous, and herbivory is restricted to lizards. Here, we show that within a group of South American lizards (Liolaemidae, ≈170 species), herbivory has evolved more frequently than in all other squamates combined and at a rate estimated to be >65 times faster. Furthermore, in contrast to other herbivorous lizards and to existing theory, most herbivorous liolaemids are small bodied and live in cool climates. Herbivory is generally thought to evolve only in reptile species that are large bodied, live in warm climates, and maintain high body temperatures. These three well known “rules” of herbivory are considered to form the bases of physiological constraints that explain the paucity of herbivorous reptile species. We suggest that the recurrent and paradoxical evolution of herbivory in liolaemids is explained by a combination of environmental conditions (promoting independent origins of herbivory in isolated cool-climate regions), ecophysiological constraints (requiring small body size in cool climates, yet high body temperatures for herbivores), and phylogenetic history. More generally, our study demonstrates how integrating information from ecophysiology and phylogeny can help to explain macroevolutionary trends.

Our experiments were designed to test the hypotheses that dietary lipids can affect whole-animal physiological processes in a manner concordant with changes in the fluidity of cell membranes. We measured (1) the lipid composition of five tissues, (2) body temperatures selected in a thermal gradient (T(sel)), (3) the body temperature at which the righting reflex was lost (critical thermal minimal [CTMin]), and (4) resting metabolic rate (RMR) at three body temperatures in desert iguanas (Dipsosaurus dorsalis) fed diets enriched with either saturated or unsaturated fatty acids. The composition of lipids in tissues of the lizards generally reflected the lipids in their diets, but the particular classes and ratios of fatty acids varied among sampled organs, indicating the conservative nature of some tissues (e.g., brain) relative to others (e.g., depot fat). Lizards fed the diet enriched with saturated fatty acids selected warmer nighttime body temperatures than did lizards fed a diet enriched with unsaturated fatty acids. This difference is concordant with the hypothesis that the composition of dietary fats influences membrane fluidity and that ectotherms may compensate for such changes in fluidity by selecting different body temperatures. The CTMin of the two treatment groups was indistinguishable. This may reflect the conservatism of some tissues (e.g., brain) irrespective of diet treatment. The RMR of the saturated treatment group nearly doubled between 30 degrees and 40 degrees C. Here, some discrete membrane domains in the lizards fed the saturated diet may have been in a more-ordered phase at 30 degrees C and then transformed to a less-ordered phase at 40 degrees C. In contrast, the RMR of the unsaturated treatment group exhibited temperature independence in metabolic rate from 30 degrees to 40 degrees C. Perhaps the unsaturated diet resulted in membranes that developed a higher degree of disorder (i.e., a certain phase) at a lower temperature than were membranes of lizards fed the saturated diet. Our study demonstrates links between dietary fats and whole-animal physiology; however, the mechanistic basis of these links, and the general knowledge of lipid metabolism in squamate reptiles, remain poorly understood and warrant further study.

The Liolaemus alticolor group (Iguania: Tropiduridae) currently includes two or three species of morphologically similar, small-bodied lizards distributed from southern Peru and Bolivia to northern Argentina and Chile. Recently, a few populations of L. alticolor from northwestern Argentina were reported to be reproductively bimodal-having both oviparous and viviparous females at the same locality. We reexamined lizards from these putatively bimodal populations and found evidence that these populations include two sympatric yet distinct species-one oviparous, the other viviparous. These species can also be distinguished from L. alticolor sensu stricto from the type locality (Tiahuanaco, Bolivia). Here we describe the two new species, L. ramirezae and L. pagaburoi, from the province of Tucuman, Argentina. Liolaemus ramirezae differs from L. alticolor in having distinct neck folds, precloacal pores in females, and an oviparous reproductive mode, and in lacking both spots on the throat in males and a vertebral line. Liolaemus pagaburoi differs from L. alticolor in having distinct paravertebral markings, slender dorsal stripes, and more rugose head scales. Recognition of these new species as distinct resolves the paradox of reproductive bimodality in L. alticolor. Interestingly, both of the new species appear to be microhabitat specialists that associate with a single species of plant in their respective habitats. As predicted by the cold-climate hypothesis, the oviparous species is distributed in a warmer climate than is the viviparous species. El grupo Liolaemus alticolor (Iguania: Tropiduridae) actualmente incluye unas dos a tres especies morf6logicamente similares. Se trata de lagartos pequenos distribuidos desde el sur de Peru y Bolivia hasta el norte de Argentina y Chile. Recientemente, unas pocas poblaciones de L. alticolor del noroeste de Argentina fueron reportadas por exhibir bimodalidad reproductiva, es decir, contar tanto con hembras oviparas como hembras viviparas en la misma localidad. En este trabajo se revisaron esas poblaciones y encontramos evidencia que las mismas incluyen dos especies simpatricas, una vivipara y la otra ovipara. Estas especies se diferencian asimismo de L. alticolor sensu stricto de la localidad tipo (Tiahuanaco, Bolivia). Aqui

We provide a critical review of a recent taxonomic revision of Chilean Liolaemus lizards (Iguania: Liolaemidae) by Pincheira-Donoso and Nunez (2005) and a recent paper (PincheiraDonoso et al. 2008), which proposed several new taxonomic and phylogenetic arrangements. We document fundamental problems with many of the proposed taxonomic revisions in both publications, which if followed, could lead to serious taxonomic confusion. In Pincheira-Donoso and Nunez (2005) a subgeneric classification is erected, which was produced by outdated methods (phenetic analyses), cannot be replicated (no matrix is presented), and is taxonomically untenable (some of the subgenera are nested within other subgenera). Most of the taxonomic groups that are proposed have been previously proposed, albeit differently constituted, yet often previous research is not given attribution; when findings are different, the research of others is either overlooked or dismissed without comment. The diagnoses of species and subspecies (including several newly proposed taxa) are often written in an authoritative manner (without supporting data or information), making them insufficient for distinguishing the focal taxon from others belonging to the same group, finally leading to uncertainty regarding the validity of several of the newly proposed taxa, combinations, or synonymies. We also describe less egregious errors of omission and commission. In Pincheira-Donoso et al. (2008), most of the proposals follow the Pincheira-Donoso and Nunez (2005) revisions, some species are allocated to groups without consistent cladistic support and other proposed relationships are based on incomplete evidence from other studies dismissing the limitations of the arrangement. Critical species are not identified in a list of material examined. Finally, Pincheira-Donoso et al. (2008) present a somewhat outdated and biased discussion of the relative value of using molecules or morphology in systematics. In light of these limitations, and in an effort to stabilize and prevent further taxonomic confusion, we provide an updated phylogenetic classification of the currently recognized lizards of the family Liolaemidae (Ctenoblepharys, Liolaemus, and Phymaturus), which is based on a consensus of studies published since the first phylogenetic major revision of the clade in 1995.