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Sarika khmeriana Pholyotha & Panha sp. nov. urn:lsid:zoobank.org:act: 13BEB7E0-40BD-480C-ABA7-72798C9E6AF2 Table 1; Figs 4 A���B, 5, 6A���F Diagnosis Sarika khmeriana sp. nov. can be characterized by a large, depressed shell, rounded on the periphery. Shell colour dark brownish and usually with pale brownish (to whitish) umbilical area. Animal has dark grey body and left shell lobe is absent. Genitalia have rather long epiphallic caecum and inner wall of penis sculptured with triangular prism penial pilasters. Spermatophore head filament with irregularly serrated longitudinal folds; tail filament bearing two spines near sperm sac and branching spines along the entire tail filament length. Etymology The specific epithet ��� khmeriana ��� refers to the Khmer Empire, of which Cambodia is the residual state. Material examined Holotype CAMBODIA ��� 1 shell (width 24.2 mm, height 12.3 mm); Kampot Province, Dang Tong District, limestone outcrops near Totong Temple, locality code C041; 10��41���59.8��� N, 104��31���30.1��� E; CUMZ 7904. Paratypes CAMBODIA ��� 6 shells, 11 alcohol-preserved specimens; same collection data as for holotype; CUMZ 7905 ��� 2 shells; same collection data as for preceding; NHMUK ��� 2 shells; same collection data as for preceding; ZRC. Other material CAMBODIA ��� 24 shells, 17 alcohol-preserved specimens; Kampot Province, Banteay Meas District, limestone outcrops at Prasat Phnom Totong Temple, locality code C042; 10��41���47.9��� N, 104��31���25.5��� E; CUMZ 7906. Description SHELL (Fig. 4 A���B). Depressed, large (shell width up to 24.2 mm, shell height up to 12.3 mm), rather thin, semi-translucent. Shell colour dark brownish on upper surface and at periphery; below periphery surrounding umbilicus pale to very pale brownish. Shell surface smooth, glossy; more glossy below periphery; suture rather shallow with narrow, whitish subsutural band. Spire slightly elevated; whorls 6���6��, increasing regularly; last whorl broadly rounded on periphery. Aperture obliquely crescentshaped; peristome simple. Columellar margin simple, slightly reflected near umbilicus. Umbilicus somewhat narrow and deep. EXTERNAL FEATURES (Fig. 5A). Living animals have monochrome dark grey body with pale grey foot sole. Caudal foss present; caudal horn elevated and large. Mantle edge well developed with three dorsal lobes and one shell lobe (see Pholyotha et al. 2018: fig. 1). Shape and size of dorsal lobes and right shell lobe (left shell lobe absent) similar to previous species. GENITALIA (Fig. 5 B���C). Atrium (at) enlarged, very short. Penis (p) cylindrical, with thin penial sheath covering proximal penis. Inner sculpture of penis very finely folded to nearly smooth then gradually transformed to triangular prism (rhombic base and acute angle on top) penial pilasters (pp) near epiphallus. Epiphallus (e) cylindrical, elongate, about two times penis length. Epiphallic caecum (ec) large, similar diameter as penis, straight and located near middle of epiphallus. Penial retractor muscle (prm) thin, attached at tip of epiphallic caecum. Flagellum (fl) slender, somewhat long, about 1.5 times epiphallus length. Vas deferens (vd) a thin tube. Vagina (v) cylindrical, similar length as penis. Dart apparatus (da) cylindrical, rather large, long, attached to atrium at penis and vagina junction. Gametolytic sac (gs) enlarged, bulbous (spermatophore inside); gametolytic duct (gd) long, cylindrical. Free oviduct (fo) cylindrical, longer than vagina, proximal end encircled with thickened tissue. Oviduct large lobules; prostate gland running alongside oviduct. SPERMATOPHORE (Fig. 6 A���F). Sperm sac (ss) enlarged, elongate-oval. Head filament (hf) enlarged (most was missing) with irregularly serrated longitudinal folds. Tail filament (tf) very long tube, region close to sperm sac bearing two spines. Spine I simple, short; spine II with complicated branching into small, numerous spinules. Spines on tail filament starting just after spine II, with complicated branching into spinules, arranged alternate (Fig. 7D) or opposite (Fig. 7F). RADULA (Fig. 5D). Teeth arranged in wide-angle U-shape with half row formula: 1���(13���14)���55 teeth. Central tooth symmetrical tricuspid with triangular-shaped mesocone; ectocones very small. Lateral teeth asymmetrical tricuspid; mesocone large, pointed cusp; endocone small, located near the tip; ectocone larger than endocone, pointed cusp, located in middle of tooth. Marginal teeth occurring around tooth numbers 13���14, obliquely bicuspid; endocone elongate, pointed cusp; ectocone small, pointed cusp. Outermost teeth gradually reduced in size as cusps to small teeth. Distribution This new species is known from two locations very close to each other, on limestone outcrops. Totong Mountain (type locality) is a small karst with an old quarry, surrounded by housing areas and is adjacent to paddy fields (Fig. 1). The second locality, Prasat Phnom Totong, about 500 m south of the type locality, is a very large and active mining site of a cement factory. Remarks Sarika khmeriana sp. nov. is quite similar in terms of shell shape with S. lactoconcha sp. nov., but this species is distinct in possessing dark brown shell on upper surface and pale brownish (to whitish) surrounding umbilicus, and left shell lobe absent (four mantle lobes); whereas S. lactoconcha sp. nov. has a monochrome pale milky shell, and well-developed left shell lobe (five mantle lobes). This new species differs from S. resplendens in having a thin penial retractor muscle and the entire tail filament of spermatophore has branching spines, whereas the genitalia of S. resplendens (see Godwin-Austen 1907: fig. 3) have a large and thickened penial retractor muscle, and the tail filament of spermatophore is without a branching spine. Compared with other species of Sarika from Cambodia, S. khmeriana sp. nov. is rounded on the periphery while S. bocourti is obtusely angulated on the periphery, and this new species has a larger shell diameter than S. benoiti. Sarika khmeriana sp. nov. also differs from M. despecta (Mabille, 1887) from northern Vietnam in having an elevated spire and narrower umbilical opening., Published as part of Pholyotha, Arthit, Sutcharit, Chirasak, Thach, Phanara, Chhuoy, Samol, Ngor, Peng Bun & Panha, Somsak, 2020, Land snail genus Sarika Godwin-Austen, 1907 (Eupulmonata: Ariophantidae) from Cambodia, with description of three new species, pp. 1-21 in European Journal of Taxonomy 674 on pages 11-15, DOI: 10.5852/ejt.2020.674, http://zenodo.org/record/3908375, {"references":["Pholyotha A., Sutcharit C. & Panha S. 2018. The land snail genus Macrochlamys Gray, 1847 from Thailand, with descriptions of five new species (Pulmonata: Ariophantidae). Raffles Bulletin of Zoology 66: 763 - 781."]}

Sarika nana Pholyotha & Panha sp. nov. urn:lsid:zoobank.org:act: 48DF9AB1-369C-4930-A006-9E57AE9DBACB Table 1; Figs 4 C–D, 6G–J, 7 Diagnosis Sarika nana sp. nov. can be characterized by medium shell size, globosely depressed, pale yellowishbrown shell, and well-rounded periphery. Animal has dark grey body and five mantle lobes. Genitalia have a rather long epiphallic caecum, short penial caecum, rather large penial verge and oval-shaped penial pilasters. Spermatophore has smooth head filament and tail filament near sperm sac bearing two spines, and terminal one-third of tail filament contains a series of short branching spines. Etymology The specific epithet ‘ nana ’ is from the Latin word ‘ nanus ’ meaning “dwarf” and refers to the small-sized species in this genus. Material examined Holotype CAMBODIA • 1 shell (width 12.6 mm, height 6.8 mm); Takeo Province, Kiri Vong District, the conglomerate hills at Phnom Bayang Temple, locality code C036; 10°38′28.2″ N, 104°50′35.8″ E; CUMZ 7907. Paratypes CAMBODIA • 24 alcohol-preserved specimens; same collection data as for holotype; CUMZ 7908 • 2 shells; same collection data as for preceding; NHMUK • 2 shells; same collection data as for preceding; ZRC. Description SHELL (Fig. 4 C–D). Globosely depressed, medium-sized (shell width up to 12.3 mm, shell height up to 6.8 mm), thin, rather translucent. Shell surface smooth, shiny; more shiny below periphery; shell colour pale yellowish brown. Entire shell consisting of 5½–6 whorls increasing regularly, separated by shallow suture. Spire slightly elevated; last whorl broad, well-rounded. Aperture obliquely oval-lunate shaped. Peristome simple. Columellar margin simple, slightly expanded near umbilicus. Umbilicus opened, wide, deep. EXTERNAL FEATURES (Fig. 7A). Living animals having monochrome pale grey body, foot sole. Caudal foss, large caudal horn present. Mantle edge well developed, dark colour, with three dorsal lobes and two shell lobes (see Pholyotha et al. 2018: fig. 1). Dorsal lobes and shell lobes similar to those of S. lactoconcha sp. nov. GENITALIA (Fig. 7 B–C). Atrium (at) very short. Penis (p) short, cylindrical with thin penial sheath covering proximal penis. Distal penis slightly enlarged with penial caecum (pc), corresponding to penial verge. Inner sculpture of penis proximally with smooth surface then transformed to thickened, corrugated transverse-folded penial pilasters (pp) surrounding penial verge near distal end. Penial verge (pv) large with blunt tip. Epiphallus (e) cylindrical, about twice penis length. Epiphallic caecum (ec) similar diameter as epiphallus, straight, located near proximal epiphallus. Penial retractor muscle (prm) thin, attached at tip of epiphallus. Flagellum (fl) slender, short, about half the length of epiphallus. Vas deferens (vd) thin tube. Vagina (v) cylindrical, little longer than penis. Dart apparatus (da) cylindrical, rather large and long, connected to atrium at vagina and penis junction. Gametolytic sac (gs) enlarged, bulbous (spermatophore inside); gametolytic duct (gd) cylindrical, long. Free oviduct (fo) cylindrical, same length as vagina, proximal end encircled with thickened, brownish tissue. Oviduct enlarged lobules; prostate gland running alongside oviduct. SPERMATOPHORE (Fig. 6 G–J). Sperm sac (ss) enlarged, elongate-oval. Head filament (hf) located subapical of sperm sac, with long, smooth surface. Tail filament (tf) about two times longer than sperm sac, region close to sperm sac bearing two spines. Spine I simple, curved, with dull tip. Spine II large, branching into spinules (antler like). Region furthest away smooth, without spine; terminal part (about one-fourth of its length) consisting of short to long branching spines arranged in row or encircling tip. RADULA (Fig. 7D). Teeth arranged in wide-angle U-shape with half row formula: 1–(10–11)–46 teeth. Central tooth symmetrical tricuspid; mesocone large, lanceolate shape; ectocones small with triangular shape. Lateral teeth asymmetrical tricuspid with large, pointed cusp mesocone; endocone small, pointed cusp, located near tip; ectocone rather large, triangular-shaped, located in middle of tooth. Marginal teeth starting around tooth numbers 10–11, obliquely bicuspid; endocone elongate, pointed cusp; ectocone small, pointed cusp. Outermost teeth gradually smaller in size from lateral teeth to edge. Distribution This new species is known only from the conglomerate mountain Phnom Bayang (type locality; Fig. 1). The habitat at the collection site is an evergreen forest mixed with fruit orchards and with outcroppings of large granite boulders. This location is surrounded by villages and is adjacent to paddy fields. Remarks Sarika nana sp. nov., a medium-sized species, can be distinguished from all species of Sarika recorded from mainland Indochina by having a penial verge. Compared to medium-sized species of Macrochlamys, body whorl of S. nana sp. nov. is relatively broader and more well-rounded on the periphery, umbilicus is relatively wider and aperture opening is less convex than M. excepta (Mabille, 1887) (Fig. 4E) and M. zero (Mabille, 1887) (Fig. 4F). The type locality of the new species is about 1000 km from the two species described from Northern Vietnam. The Thai species M. brunnea Möllendorff, 1902 has much narrower umbilical opening than this new species (see Pholyotha et al. 2018: fig. 8a). Unfortunately, the anatomical data of M. brunnea, M. excepta and M. zero is unavailable for further comparison.

Genus Sarika Godwin-Austen, 1907 Sarika Godwin-Austen, 1907: 179. ��� Blanford & Godwin-Austen 1908: 276. ��� Zilch 1959: 325. ��� Schileyko 2002: 1288. ��� Pholyotha et al. 2020. Type species Helix resplendens Philippi, 1846, by original designation., Published as part of Pholyotha, Arthit, Sutcharit, Chirasak, Thach, Phanara, Chhuoy, Samol, Ngor, Peng Bun & Panha, Somsak, 2020, Land snail genus Sarika Godwin-Austen, 1907 (Eupulmonata: Ariophantidae) from Cambodia, with description of three new species, pp. 1-21 in European Journal of Taxonomy 674 on page 5, DOI: 10.5852/ejt.2020.674, http://zenodo.org/record/3908375, {"references":["Blanford W. T. & Godwin-Austen H. H. 1908. Mollusca: Testacellidae and Zonitidae. In: Bingham CT (ed.) The Fauna of British India including Ceylon and Burma. Taylor and Francis, London.","Zilch A. 1959. Gastropoda, Euthyneura. In: Schindewolf O. H. (ed.) Handbuch der Palaozoologie, Volume 6: 1 - 400. Gebruder Borntraeger, Berlin.","Pholyotha A., Sutcharit C., Tongkerd P., Lin A. & Panha S. 2020. Taxonomic revision of the land snail genera Macrochlamys Gray, 1847 and Sarika Godwin-Austen, 1907 (Eupulmonata: Ariophantidae) from Southeastern Myanmar, with descriptions of three new species. Molluscan Research 40: 183 - 204. https: // doi. org / 10.1080 / 13235818.2020.1723041","Philippi R. A. 1846. Vier neue Konchylienarten. Zeitschrift fur Malakozoologie 3: 191 - 192."]}

Species’ responses to seasonal environmental variation can influence trophic interactions and food web structure within an ecosystem. However, our ability to predict how species’ interactions will vary spatially and temporally in response to seasonal variation unfortunately remains inadequate within most ecosystems. Fish assemblages in the Tonle Sap Lake (TSL) of Cambodia—a dynamic flood-pulse ecosystem—were studied for five years (2010–2014) using stable isotope and Bayesian statistical approaches to explore both within- and among-species isotopic niche variation associated with seasonal flooding. Roughly 600 individual fish specimens were collected during 19 sampling events within the lake. We found that fishes within the same species tended to have a broader isotopic niche during the wet season, likely reflecting assimilation of resources from either a wider range of isotopically distinct prey items or a variety of habitats, or both. Furthermore, among-species isotopic niches tended to overlap and range more broadly during the wet season, suggesting that floodplain inundation promotes exploitation of more diverse and similar resources by different species in the fish community. Our study highlights that the flood-pulse dynamic that is typical of tropical aquatic ecosystems may be an essential element supporting freshwater fish community structure and the fish diversity that underpins the TSL food web. This flow regime is currently threatened by regional dam development, which may in turn impact the natural function and structure of the fishery food web.