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Grenada Bank Zygodontomys: natural or human-mediated dispersal? Although genetic data are not available to determine the timing of divergence between Grenada Bank Zygodontomys and neighbouring populations (Brace et al. 2015), conspecificity of these populations indicates that divergence must have been geologically recent. It is possible that arrival of Zygodontomys on the Grenada Bank represents a natural overwater dispersal event mediated by northward-flowing oceanic currents within the southern Caribbean basin (Hedges 1996). The possibility of natural overwater dispersal is supported by the historical occurrence of the mainland Neotropical oryzomyine species Oryzomys gorgasi on Curaçao (Voss & Weksler 2009), another southern Caribbean island that remained unconnected to the South American mainland during the Late Quaternary, and which also supported endemic oryzomyine taxa (Hooijer 1959; Zijlstra 2012; Zijlstra et al. 2014). Conversely, the occurrence of this widespread species on the Grenada Bank might instead indicate deliberate or accidental human-mediated translocation (‘ethnophoresy’), suggesting that Megalomys might be the islands’ only native rice rat. Numerous mammal species, including several rodents, are known to have been translocated around the insular Caribbean as food resources during prehistory, either between islands or from the South American mainland (Hooijer 1963; Newsom & Wing 2004; Silva Taboada et al. 2007; Díaz-Franco & Jiménez Vásquez 2008; Giovas et al. 2012; Giovas 2019a; LeFebvre et al. 2019). In addition to guinea pigs (Cavia porcellus), which were domesticated between 5500 and 2500 BCE and were moved widely around the circum-Caribbean region, numerous non-native South American mammal taxa are also present in pre-Columbian midden contexts on Grenada and Carriacou (Dasyprocta, Dasypus, Didelphis, Mazama, Odocoileus, Tayassu / Pecari) (Newsom & Wing 2004; Giovas et al. 2012, 2018b). Indeed, human movements continued between Grenada and northern South America throughout the Late Ceramic Age, and were associated with mainland-driven shifts in resource use and material culture on Grenada (Hanna 2018). The arrival of Zygodontomys on the Grenada Bank might therefore represent deliberate translocation as a food resource. However, Zygodontomys is smaller than other oryzomyines that occur regularly in pre-Columbian middens in the Lesser Antilles (Table 5), and is also much smaller than other non-native mammal species present in middens on the Grenada Bank (Giovas 2019a). Small-bodied muroid rodents are now present on many islands worldwide as a result of widespread inadvertent human-mediated translocation during the historical period and recent prehistory (e.g. Yalden 1999; Searle et al. 2008; Bonhomme et al. 2010). The occurrence of Zygodontomys in archaeological contexts might therefore reflect commensalism rather than consumption, with its arrival on the Grenada Bank representing accidental rather than deliberate prehistoric introduction. Palaeontological investigation and/or ancient biomolecular research are required to test between these varying hypotheses concerning the colonisation pathway of Zygodontomys.

Megalomys camerhogne sp. nov. Holotype. GNM A1 -E-10-F1.S2, left mandible with m1 (Figure 5a–c, Figure 6a). Type locality. Pearls, pre-Columbian archaeological site (associated AMS dates, 400–1650 CE); Unit E (100–110 centimetres below datum), dated to Saladoid–Barrancoid period (200–750 CE); Saint Andrew, Grenada (12.14573, -61.613847). Hypodigm. Other studied material from Pearls: three edentulous right mandibles (GNM A1-E-10-F1.S1, S7, S8); two isolated m1s (GNM A1-E-10-F1.S28, GNM A1-E-10-F1.S 30); one isolated incisor (GNM A1-E-10- F1.S24); one right humerus (UF 164); two left radii (GNM A1-E-10-F1.S15, S16); two right radii (GNM A1-E-10- F1.S20, S29); one right ulna (GNM A1-E-10-F1.S17); one left femur (GNM A1-E-10-F1.S27); three right tibiae (UF 164, GNM A1-E-10-F1.S18, S23); two right calcanea (GNM A1-E-10-F1.S21, S22); one left ilium (GNM A1- E-10-F1.S19); one right ilium (UF 164); two caudal vertebrae (GNM A1-E-10-F1.S25, S26) (Figure 5 d-f). Distribution. Known from the Holocene of Grenada. Only known so far from archaeological contexts at Pearls (Saladoid–Barrancoid to Suazan–Troumassoid periods, 400–1650 CE). Etymology. From the Indigenous Caribbean (Arawakan) name for Grenada, in recognition of the island’s people and their heritage; neuter noun. Diagnosis. Megalomys camerhogne sp. nov. can be distinguished from other described Megalomys species by the following combination of characters: m1 has four alveolar roots, m2 has three alveolar roots, and m3 has two alveolar roots; capsular process of lower incisor alveolus well-developed as conspicuous swollen projection; largest lower toothrow length and body mass estimate for any Megalomys species; posterior margin of mandibular symphysis extends posteroventrally beyond margin of ramus as prominent point; entepicondylar foramen and supratrochlear foramen both absent on humerus (Table 1). Description. Known only from incomplete skeletal material. Character numbering and character state coding from Weksler (2006). Mandible: Robust, broad and high. Coronoid process gently falciform, raised slightly above maximum height of broad, squared condylar process. Sigmoid notch rounded, deep and wide. Mandibular foramen large and elongated; at base of condylar process.Angular process very broad, with gently curved outline and well-defined inferior masseteric ridge reaching distal margin; masseteric fossa broad and deep. Capsular process of lower incisor alveolus welldeveloped as conspicuous swollen projection (character 45: state 2). Mental foramen opens laterally to diastema, at body of mandible (character 44: state 0). Superior and inferior masseteric ridges converge anteriorly as open chevron, joining at their anteriormost point (character 46: state 0). Confluence of masseteric crest horizontally level with mental foramen, and vertically aligned with anterior portion of m1 (character 47: state 0). Posterior margin of mandibular symphysis extends posteroventrally beyond margin of ramus as prominent point. Lower dentition: Molars bunodont and brachydont (character 54: state 0). Labial flexi closed off by cingula (character 55: state 0). First lower molar (m1) with two large roots and two accessory central roots (character 50: state 2). Anteroconid undivided; containing anteromedian fossettid (character 70: state 1). Anterolabial cingulum present (character 71: state 1); protoflexid narrowly compressed labially, with bifurcated apex, and obliquely mesiolinguad, almost reaching anteromedian fossettid. Hypoflexid transverse, narrow and deep. Small, low ectostylid present; ectolophid absent (character 72: state 0). Metaflexid short and narrow. Mesolophid and mesostylid present, connected to entoconid by lingual cingulum (character 73: state 0). Posteroflexid long and outlines entoconid. Metaconid and entoconid subquadrate, protoconid and hypoconid subtriangular. Second and third lower molars (m2 and m3) not preserved in available material, but root condition can be diagnosed from alveolar configuration: m2 with three alveolar roots (character 51: state 1), and m3 with two alveolar roots. Postcrania: Available appendicular skeletal elements large. Entepicondylar foramen of humerus absent (character 82: state 1). Supratrochlear foramen of humerus absent (character 83: state 0). Femur has well-developed flattened lateral crest that extends almost halfway along diaphysis. Calcaneum shows gap between proximal edge of short trochlear process and posterior articular facet (character 84: state 1). Craniodental measurements given in Table 2. Mean body mass estimated as 348 g (Table 5). Remarks. The large Grenada rice rat can be assigned confidently to Megalomys based on the following characters: mental foramen lateral to diastema; lower incisor alveolus with well-developed capsular process; superior and inferior masseteric ridges join at their anteriormost point as an open chevron; confluence of masseteric crest horizontally level with mental foramen and vertically aligned with anterior portion of m1. In comparison to other rice rat genera from the main island chain of the Lesser Antilles, it differs from Pennatomys in possessing superior and inferior masseteric ridges that join at their anteriormost point as an open chevron (the anterior portion of these ridges are conjoined as a single ridge in Pennatomys) and in lacking a supratrochlear foramen on the humerus, and it differs from Antillomys in possessing a greater number of roots on m1 and m2 (only two roots are present on both of these teeth in Antillomys). The Grenada Megalomys differs from all previously described Megalomys species in both morphological characteristics and available measurements. It differs morphologically in possessing four roots on m1 (three roots on m 1 in M. audreyae); in possessing three roots on m2 and two roots on m3 (three roots on both m2 and m 3 in M. desmarestii and M. luciae; two roots on both m2 and m 3 in ‘ M.’ curazensis and M. georginae), and in lacking both an entepicondylar foramen and a supratrochlear foramen on the humerus (foramina absent in M. desmarestii; present in ‘ M.’ curazensis and M. georginae; condition unknown in M. luciae). It is also the largest known representative of Megalomys, with the greatest available measurement for lower molar toothrow length in any other Megalomys species (M. desmarestii, 10.35 mm; Turvey et al. 2012) corresponding to the lower end of the available measurement range for M. camerhogne (10.35–10.67 mm; Table 2)., Published as part of Mistretta, Brittany A., Giovas, Christina M., Weksler, Marcelo & Turvey, Samuel T., 2021, Extinct insular oryzomyine rice rats (Rodentia: Sigmodontinae) from the Grenada Bank, southern Caribbean, pp. 434-460 in Zootaxa 4951 (3) on pages 443-445, DOI: 10.11646/zootaxa.4951.3.2, http://zenodo.org/record/4668145, {"references":["Weksler, M. (2006) Phylogenetic relationships of the oryzomyine rodents (Muroidea: Sigmodontinae): separate and combined analyses of morphological and molecular data. Bulletin of the American Museum of Natural History, 296, 1 - 149. https: // doi. org / 10.1206 / 0003 - 0090 (2006) 296 [0001: PROORM] 2.0. CO; 2","Turvey, S. T., Weksler, M. & Brace, S. (2012) A new species of recently extinct rice rat (Megalomys) from Barbados. Mammalian Biology, 77, 404 - 413. https: // doi. org / 10.1016 / j. mambio. 2012.03.005"]}

Zygodontomys brevicauda (Allen & Chapman, 1893) Distribution. Recorded from the Grenada Bank from Troumassan–Troumassoid and Suazan–Troumassoid horizons (associated AMS dates, 600–1400 CE) at Sabazan, Carriacou, and Saladoid–Barrancoid to Suazan–Troumassoid horizons (associated AMS dates, 400–1650 CE) at Pearls, Grenada. Material. Sabazan, Carriacou: left maxilla with M1–M3 (SFU 0707 CSZ 000036-M-84), left maxilla with M3 (SFU 0707 CSZ 000133-M-248), juvenile right maxilla with M3 (SFU 0707 CSZ 000024-M-249), two zygomatic processes (SFU 0707 CSZ 000036-M-82, 0707 CSZ 000101-M-136), three isolated M1s (SFU 03 CAR 000235-M- 211, 0707 CSZ 000027-M-219, 0707 CSZ 000199-M-225), isolated M2 (SFU 0707 CSZ 000215-M-134-B), isolated M3 (SFU 0707 CSZ 000101-M-135), three upper incisors (SFU 03 CAR 000235-M-205, 0707 CSZ 000164-M-234, 0707 CSZ 000241-M-235), left mandible with attached m1-m2 and associated m3 (SFU 03 CAR 000235-M-191), right mandible with m1-m2 (SFU 0707 CSZ 000085-M-41-A), right mandible with m3 (SFU 0707 CSZ 000133-M- 247), right mandible fragment with m1 (SFU 03 CAR 000235-M-213), three isolated m1s (SFU 0707 CSZ 000086- M-100, 0707 CSZ 000114-M-106, 0707 CSZ 000042-M-215), four isolated m2s (SFU 0707 CSZ 000215-M-134-A, 03 CAR 000235-M-198, 03 CAR 000235-M-208, 0707 CSZ 000207-M-230), two edentulous right mandibles (SFU 0707 CSZ 000063-M-67-A1, 0707 CSZ 000063-M-67-A2), anterior fragment of left mandible (SFU 03 CAR 000235- M-199), two posterior mandibular bodies (SFU 03 CAR 000235-M-194, 0707 CSZ 000101-M-233), two distal humeri (SFU 0707 CSZ 000086-M-98, 03 CAR 000235-M-203), five calcanea (SFU 0707 CSZ 000064-M92, 0707 CSZ 000101-M-102, 0707 CSZ 000114-M-109, 0707 CSZ 000127-M-116, 03 CAR 000235-M-209) (Figure 7). Pearls, Grenada: one right mandible with m1-m3 (GNM A1-E-10-F1.S3), four left edentulous mandibles (GNM A1-E-10-F1.S4, S5, S6, S9), two left femora (GNM A1-E-10-F1.S11, S12), two right femora (UF 164, GNM A1- E-10-F1.S10); one unsided femur (GNM A1-E-10-F1.S14) (Figure 8). Description. Known only from incomplete skeletal material. Character numbering and character state coding from Weksler (2006). Cranium: Zygomatic plate broad, creating zygomatic notch (character 28: state 1). Posterior margin of zygomatic plate apparently situated anterior to alveolus of M1, but maxillary material fragmentary and broken in adult individuals so difficult to confirm (character 28: state 0?). Posterior margins of incisive foramina conspicuously projecting between procingula of M1 (character 31: state 0). Bony palate with shallow lateral longitudinally oriented troughs (character 33: state 0). Upper dentition: Enamel band of upper incisors without distinct labial bevel (character 53: state 0). Molars bunodont and brachydont (character 54: state 0). Labial flexi closed off by cingula (character 55: state 0). Maxillary toothrows apparently parallel (character 56: state 0). M1 with three main roots; labial accessory root absent; small central accessory rootlet present (character 49: state 0). Flexi of M1 and M2 do not interpenetrate (character 57: state 0). Anterocone of M1 undivided, anteromedian flexus and internal fold of procingulum absent (character 58: state 2). Anteroloph and anteroflexus absent on M1 (character 59: state 3). Protostyle absent on M1 (character 60: state 0). Protocone and paracone of M1 forming single transversely oriented dentine basin with no enamel connection (character 61: state 2). Mesolophs absent on M1 and M2 (character 62: state 2). Median mure centrally located on M1, connected to both protocone and paracone (character 63: state 0). No unworn adult M2 or M3 available, so specific characters of unworn occlusal surfaces of these teeth not diagnosable. Mandible: Coronoid process low, falciform and sharply curved backward; raised slightly above maximum height of evenly rounded condylar process. Sigmoid notch rounded, shallow and wide. Mandibular foramen narrow and elongated. Angular process damaged in all available specimens; with broad, deep masseteric fossa. Capsular process well-developed as conspicuous swelling slightly posteroventral to coronoid process (character 45: state 2). Ramus quite shallow. Mental foramen opens dorsolabially on diastema anterior to m1 (character 44: state 1). Superior and inferior masseteric ridges converge anteriorly and fuse as a single robust masseteric crest below m1 (character 46: state 1). Anterior edge of masseteric crest below anterior portion of m1 (character 47: state 0). Lower dentition: m1 with two roots in total; labial and lingual accessory roots absent (character 50: state 0). m1 with undivided anteroconid and anteromedian fossettid present (character 70: state 1), and with anterolabial cingulum present (character 71: state 1). Ectolophid and ectostylid absent on m1 (character 72: state 0). Mesolophids absent on m1 and m2 (character 73: state 2). m2 and m3 with three roots, sometimes also with small central accessory rootlet between two anterior roots (character 51: state 1). Anterolabial cingulum present on m2 (character 74: state 0). Small metaflexid present, defining small anterolophid, on several m2 and m 3 specimens (character 75: state 1). Anterolabial margin of m3 with shelflike cingulum (character 76: state 0). Posteroflexid absent on m3 (character 77: state 2). Postcrania: Entepicondylar foramen of humerus absent (character 82: state 1). Supratrochlear foramen of humerus present (character 83: state 1). Calcaneum shows gap between proximal edge of short trochlear process and posterior articular facet (character 84: state 1). Craniodental measurements given in Tables 3–4. Body mass estimated as 63.4 g (Carriacou population), and 62.2 g (Grenada population) (Table 5). Remarks. The small Grenada Bank oryzomyine is assigned to Zygodontomys because it shows the characteristic tetralophodont occlusal molar morphology of this genus (all other Caribbean endemic oryzomyine taxa show strongly pentalophodont molars), and the presence of the following diagnostic apomorphic character states for the genus, as recovered in phylogenetic analysis: M1 procingulum without anteroloph; mesolophs and mesolophids not present on molars; paracone-protocone with basined connection; posterior margins of incisive foramina projecting conspicuously between first molars. Specimens from Carriacou and Grenada show similar morphological characters and are closely comparable in toothrow measurements, and so are interpreted as representing the same taxon. Zygodontomys is one of the most abundant mammal genera in mainland Central America and northern South America, where it is widely distributed across open vegetation formations (non-forest savanna-type habitats) (Voss 1991; Bonvicino et al. 2009). The genus has also been recorded on several continental-shelf islands in the southern Caribbean. It occurs today on Trinidad, Tobago and some of their satellite islets, which are only ~ 125 km from Grenada today at their closest point, where it also inhabits lowland and montane rainforest (Allen & Chapman 1893; Voss 1991). It is also known from the Late Quaternary fossil record of Aruba (Hooijer 1967). Seventeen nominal extant taxa have variously been assigned to Zygodontomys (Cabrera 1961; Hershkovitz 1962; Honacki et al. 1982; Reig 1986), but only two species were recognized in the comprehensive morphological review by Voss (1991) and followed by subsequent authors: Z. brevicauda (Allen and Chapman, 1893), which occurs from southwest Costa Rica to northern Amazonia, and Z. brunneus Thomas, 1898, which is restricted to Andean intermontane valleys in western Colombia (Pardiñas et al. 2017). Extant insular populations from Trinidad, Tobago, and nearby continental-shelf islets represent Z. brevicauda, the type specimen of which was collected in Trinidad (Allen & Chapman 1893; Voss 1991; Pardiñas et al. 2017), although some of these populations have also previously been assigned to the now-unrecognized taxa Akodon frustrator, Z. brevicauda tobagi, and Z. brevicauda soldadoensis (Allen & Chapman 1897; Thomas 1900; Goodwin 1962, 1965). Late Quaternary material from Aruba was also assigned to Z. cf. brevicauda (Hooijer 1967). However, molecular phylogenetic analysis indicates that populations traditionally assigned to Z. brevicauda across northern Amazonia and continental-shelf Pacific islands show deep middle-upper Pleistocene divergences and probably represent multiple undescribed species (Bonvicino et al. 2009; González et al. 2010). The two currently recognized Zygodontomys species differ in size and in molar lingual profile and occlusal architecture (Voss 1991). Where both species occur sympatrically, Z. brevicauda is much smaller than Z. brunneus, although some other populations of Z. brevicauda, in particular extant insular populations, are also relatively large and can exhibit comparable craniodental dimensions to Z. brunneus (Figure 9). Upper molars of Z. brunneus are hypsodont, with narrow re-entrant folds extending two-thirds to three-quarters of the depth of the unworn crown in lingual view. Upper and lower molars in Z. brunneus also show an oblique arrangement of folds and crests, with anterior and median mures and murids not colinear along the tooth midline but instead disrupted by small anterior deflections of the lingual reentrant folds and by corresponding medial deflections of the interior labial folds. In contrast, upper molars of Z. brevicauda are low-crowned, with wide re-entrant folds usually extending only half the depth of the unworn crown in lingual view. Upper and lower molars in Z. brevicauda have colinear anterior and median mures and murids with principal cusps positioned symmetrically in opposite labial-lingual pairs, with M1 exhibiting labial re-entrant folds that bend abruptly around the anteromedial margin of the paracone and metacone, and lingual re-entrant folds that run straight from the lingual margin to the tooth midline (Voss 1991). Zygodontomys material from both Carriacou and Grenada cannot be differentiated morphologically from extant populations of Z. brevicauda on the basis of diagnostic molar lingual profile and occlusal architecture. Dental measurements for specimens from the Grenada Bank (occlusal upper toothrow length, M1 width) are larger than comparative measurement series available for most mainland populations of Z. brevicauda, but fall within the upper end of existing size variation seen in living insular populations, especially compared with the geographically nearby extant populations on Trinidad and Tobago which are also morphometrically divergent and substantially larger than adjacent mainland populations (Voss 1991; Figure 9). No comparative measurements are available for Late Quaternary Zygodontomys material from Aruba, but this material also matches Z. brevicauda in molar morphology (Hooijer 1967). Three subspecies are currently recognized within Z. brevicauda: Z. b. brevicauda, Z. b. cherriei (Allen, 1895), and Z. b. microtinus (Thomas, 1894). These subspecies are differentiated largely by population-level frequencies of qualitative cranial traits related to stapedial arterial circulation and fenestration of the mesopterygoid fossa (Voss 1991), characters that are not preserved in available Zygodontomys material from the Grenada Bank. However, the subspecies also differ in some cladistic character states recognised by Weksler (2006). The Grenada Bank Zygodontomys shares two synapomorphies with Z. b. cherriei to the exclusion of Z. b. brevicauda: (i) capsular process well-developed as conspicuous swelling slightly posteroventral to coronoid process (character 45: state 2); (ii) superior and inferior masseteric ridges converge anteriorly and fuse as single robust masseteric crest below m1 (character 46: state 1)., Published as part of Mistretta, Brittany A., Giovas, Christina M., Weksler, Marcelo & Turvey, Samuel T., 2021, Extinct insular oryzomyine rice rats (Rodentia: Sigmodontinae) from the Grenada Bank, southern Caribbean, pp. 434-460 in Zootaxa 4951 (3) on pages 445-450, DOI: 10.11646/zootaxa.4951.3.2, http://zenodo.org/record/4668145, {"references":["Allen, J. A. & Chapman, F. M. (1893) On a collection of mammals from the island of Trinidad, with descriptions of new species. Bulletin of the American Museum of Natural History, 5, 203 - 234.","Weksler, M. (2006) Phylogenetic relationships of the oryzomyine rodents (Muroidea: Sigmodontinae): separate and combined analyses of morphological and molecular data. Bulletin of the American Museum of Natural History, 296, 1 - 149. https: // doi. org / 10.1206 / 0003 - 0090 (2006) 296 [0001: PROORM] 2.0. CO; 2","Voss, R. S. (1991) An introduction to the Neotropical muroid genus Zygodontomys. Bulletin of the American Museum of Natural History, 210, 1 - 113.","Bonvicino, C. R., Goncalves, P. R., de Oliveira, J. A., de Oliveira, L. F. B. & Mattevi, M. S. (2009) Divergence in Zygodontomys (Rodentia: Sigmodontinae) and distribution of Amazonian savannas. Journal of Heredity, 100, 322 - 328. https: // doi. org / 10.1093 / jhered / esn 105","Hooijer, D. A. (1967) Pleistocene vertebrates of the Netherlands Antilles. In: Martin, P. S. & Wright, H. E. Jr. (Eds.), Pleistocene Extinctions: The Search for a Cause. Yale University Press, New Haven, Connecticut, pp. 399 - 406.","Cabrera, A. (1961) Catalogo de los mamiferos de America del Sur. Revista del Museo Argentino de Ciencias Naturales \" Bernardino Rivadavia \", 4, 309 - 732.","Hershkovitz, P. (1962) Evolution of Neotropical cricetine rodents (Muridae) with special reference to the phyllotine group. Fieldiana Zoology, 46, 1 - 524. https: // doi. org / 10.5962 / bhl. title. 2781","Honacki, J. H., Kinman, K. E. & Koeppl, J. W. (1982) Mammal Species of the World. Allen Press, Lawrence, Kansas, 694 pp.","Reig, O. A. (1986) Diversity patterns and differentiation in high Andean rodents. In: Vuilleumier, F. & Monasterio, M. (Eds.), High Altitude Tropical Biogeography. Oxford University Press, New York, New York, pp. 404 - 439.","Thomas, O. (1898) On indigenous Muridae in the West Indies; with the description of a new Mexican Oryzomys. Annals and Magazine of Natural History, Series 7, 1 (2), 176 - 180. https: // doi. org / 10.1080 / 00222939808677948","Pardinas, U. F. J., Myers, P., Leon-Paniagua, L., Ordonez Garza, N., Cook, J. A., Krystufek, B., Haslauer, R., Bradley, R. D., Shenbrot, G. I. & Patton, J. L. (2017) Family Cricetidae (true hamsters, voles, lemmings and New World rats and mice). In: Wilson, D. E., Lacher, T. E. & Mittermeier, R. A. (Eds.), Handbook of the Mammals of the World. 7. Rodents II. Lynx Edicions, Barcelona, pp. 204 - 535.","Allen, J. A. & Chapman, F. M. (1897) On a second collection of mammals from the island of Trinidad, with descriptions of new species and a note on some mammals from the island of Dominica, W. I. Bulletin of the American Museum of Natural History, 9, 13 - 30.","Thomas, O. (1900) Descriptions of new Neotropical mammals. Annals and Magazine of Natural History, Series 7, 5 (27), 269 - 274. https: // doi. org / 10.1080 / 00222930008678282","Goodwin, G. G. (1962) Descriptions of two new rodents from Tobago, the West Indies, and of Zygodontomys brevicauda tobagi Thomas. American Museum Novitates, 2096, 1 - 9.","Goodwin, G. G. (1965) A new subspecies of Zygodontomys brevicauda from Soldado Rock, Trinidad, the West Indies (Rodentia, Cricetidae). American Museum Novitates, 2238, 1 - 10.","Gonzalez, P., Sawyer, Y. E., Avila, M., Armien, A. G., Armien, B. & Cook, J. A. (2010) Variation in cytochrome- b haplotypes suggests a new species of Zygodontomys (Rodentia: Cricetidae) endemic to Isla Coiba, Panama. Zoologia, 27, 660 - 665. https: // doi. org / 10.1590 / S 1984 - 46702010000400014"]}