Marmosa zeledoni Goldman, 1911

Part, Tate’, The Species In, Mexicana’, And, Closely, Mitis’ Sections And Other & Forms, Related, 2010, A Revision Of The Didelphid Marsupial Genus Marmosa, Bulletin of the American Museum of Natural History 2010 (334), pp. 1-83 : 37-42

Marmosa zeledoni Goldman, 1911 Figures 19, 20

? Didelphys murina: Alston, 1880: 200 . Part, not

Didelphis murina Linnaeus, 1758 .? Didelphys [(Micoureus)] murina: Thomas, 1888:

343. Part, not Didelphis murina Linnaeus, 1758 . Didelphys (Micoureus) murina: Allen, 1891: 218 .

Name combination.? Didelphis (Micoureus) murina: Allen, 1893: 240 .? Marmosa murina: Thomas, 1895: 58 . Name

combination.? Marmosa murina: Allen, 1897: 44 .

Marmosa mexicana: Bangs, 1902: 19 . Part, not Marmosa murina mexicana Merriam, 1897 .

? Marmosa murina: Allen, 1908: 648 .

Marmosa murina: Allen, 1910: 92 . Part, not Didelphis murina Linnaeus, 1758 .

Marmosa zeledoni Goldman, 1911: 238 . Type locality ‘‘Navarro, Costa Rica.’’

? Marmosa murina zeledoni: Allen, 1912: 73 . Part; name combination.

[ Didelphis (Marmosa) ] zeledoni: Matschie, 1916: 270 . Name combination.

Marmosa zeledoni: Elliot, 1917: 2 .

Marmosa mexicana zeledoni: Goldman, 1917: 108 . Name combination.

[ Marmosa (Marmosa) ] mexicana zeledoni: Cabrera, 1919: 37 .

Marmosa mexicana zeledoni: Tate, 1933: 135 .

Marmosa mexicana zeledoni: Hall, 1981: 16 . Part.

Marmosa mexicana: Honacki et al., 1982: 22 . Part, not Marmosa murina mexicana Merriam, 1897 .

Marmosa mexicana: Eisenberg, 1989: 37 . Part, not Marmosa murina mexicana Merriam, 1897 .

Marmosa mexicana: Alonso-Mejía and Medellín, 1992: 1 . Part, not Marmosa murina mexicana Merriam, 1897 .

Marmosa mexicana: Gardner, 1993: 18 . Part, not Marmosa murina mexicana Merriam, 1897 .

Marmosa mexicana: Emmons, 1997: 26 . Part, not Marmosa murina mexicana Merriam, 1897 .

Marmosa mexicana: Reid, 1997: 47 . Part, not Marmosa murina mexicana Merriam, 1897 .

Marmosa mexicana: Nowak, 1999: 21 . Part, not Marmosa murina mexicana Merriam, 1897 .

Marmosa mexicana: Voss and Jansa, 2003: 75 . Part, not Marmosa murina mexicana Merriam, 1897 .

Marmosa robinsoni: Voss and Jansa, 2003: 75 . Part, not Marmosa robinsoni Bangs, 1898 .

Marmosa mexicana: Brown, 2004: 59 . Part, not Marmosa murina mexicana Merriam, 1897 .

[ Marmosa mexicana ] savannarum: Gardner, 2005: 9. Part, not Marmosa mexicana savannarum Goldman, 1917 .

TYPE MATERIAL: The holotype (by original designation, USNM 12885 ) is a young adult (age class 6) male specimen prepared as a skin and skull ; the skin is in good condition (except for a naked area on the left side), but the skull is partially damaged (missing the tips of both nasals, lacking most of the basicranium, and with a loose supraoccipital).

TYPE LOCALITY: The holotype was collected by J. Cooper on 1 March 1878 at Navarro (gazetteer entry 71; appendix), ‘‘[a] small village about 5 miles [8 km] south of Cartago on the Caribbean slopes of the Cordillera Central’ ’ in Cartago province, Costa Rica ( Goodwin, 1946: 456) .

MORPHOLOGICAL DIAGNOSIS: Midrostral fur usually not contrasting sharply in color with fur of crown; dark median rostral stripe absent or inconspicuous; dark facial mask usually not extending posteriorly to contact base of ear; dorsal body pelage usually dull, dark, reddish brown; dorsal cover hairs 8– 10 mm in length, guard hairs 10–12 mm; gray-based ventral pelage (covering the sides of chest, abdomen, and upper inguinal region, sometimes extending to the sides of neck, rarely to the inner parts of arms and legs) with reddish or brownish hair tips; selfcolored ventral pelage (extending as a continuous median stripe of variable width from chin to anus) yellowish or orangish. Tail dark brown (indistinctly paler ventrally in some individuals), without any consistent pattern of scale arrangement (both spiral and annular patterns coexisting); 16–18 scales/cm on dorsal surface at caudal midlength; caudal scale hairs dark brown, usually detectable without magnification; central hair of each caudal-scale triplet as long as 1.5 scales (sometimes two scales) long. Gular gland present. Mammae 4–1–4 5 9 or 5–1–5 5 11. Lateral and medial carpal tubercles present in mature adult males; medial carpal tubercle long (reaching the base of the pollex), with subequal but recognizable proximal and distal segments divided by a shallow sulcus.

Length of rostral process of premaxillae similar to I1 height. Orbitosphenoid-alisphenoid suture approximately twice as long as height of sphenorbital fissure in lateral view. Supraorbital ridges subparallel, slender, and dorsally reflected; postorbital processes usually indistinct or absent; temporal ridges subparallel, never strongly convergent posteriorly. Palatine fenestrae absent (but tiny asymmetrical palatal perforations are sometimes present); posterolateral palatal foramina usually shorter than M4 (measured across paracone-metacone). Tympanic wing of ali- sphenoid laterally compressed, with ventral surface moderately pointed or bluntly keeled; medial process of ectotympanic usually indistinct or absent. I1 hypsodont, normally present in adults; crown of I2 sharply defined in relation to root; C1 without accessory cusps; preparacrista connected to stylar cusp B on M1–M3; stylar cusps D and E confluent, not separated by a distinct notch on M2.

COMPARISONS: Qualitative and morphometric comparisons between Marmosa zeledoni and M. mexicana were provided in the preceding account. In Central America, M. zeledoni overlaps geographically with two other congeners, M. isthmica and M. robinsoni , and it also co-occurs with the former species in western Colombia.

Marmosa zeledoni and M. isthmica overlap broadly in all measured dimensions (tables 4–7), and they are also externally similar in qualitative characters. On average, however, M. isthmica is the larger species, a difference that is best appreciated when size comparisons are made between specimens of the same age and sex, and there are subtle but diagnostically useful differences in some skin characters. In side-by-side comparisons, the midrostral fur of zeledoni is usually darker and contrasts less abruptly in coloration with the fur of the crown than in isthmica (which usually has much paler midrostral than coronal fur), and there is sometimes an indistinct posterior extension of the dark circumocular mask to the base of the ear in zeledoni that is not seen in isthmica . Although the body pelage is similarly pigmented in both forms, the dorsal fur of zeledoni is often a darker and duller hue of reddish brown than the somewhat brighter, orangish brown of isthmica . Additionally, the exposed skin of the tail is usually dark grayish brown above and below in zeledoni , whereas the tail is a lighter shade of brown and is often indistinctly paler below in isthmica . In dorsal cranial view, the supraorbital ridges of zeledoni are subparallel, slender, do not project laterally over the orbital fossae, and seldom form distinct postorbital processes; behind the orbits, the temporal ridges maintain this subparallel configuration onto the braincase. By contrast, the supraorbital ridges of isthmica are thicker and diverge more strongly posteriorly as they project laterally over the orbital fossae; postorbital processes are usually well developed in mature adult male specimens, which have correspondingly better-defined postorbital constrictions, and whose temporal ridges often converge posteriorly on the braincase. In ventral cranial view, the posterolateral palatal foramina are usually smaller in zeledoni than they are in isthmica .

Marmosa zeledoni overlaps broadly in measured external dimensions with M. robinsoni , although it has visibly smaller ears. In side-by-side comparisons of skins, the midrostral fur color exhibits consistently less contrast with the color of the coronal fur in zeledoni than in robinsoni , and the dorsal body pelage of zeledoni is consistently redder than that of robinsoni (whose dorsal fur is usually some shade of yellowish or grayish brown). Whereas the medial carpal tubercles of mature adult male specimens of zeledoni are divided by a shallow sulcus into subequal and morphologically similar proximal and distal segments, the medial carpal tubercles of like-aged male robinsoni consist of a globular proximal segment and a commashaped distal segment. Under low magnification, the tail appears to be more sparsely haired in zeledoni than in robinsoni , a visual effect of the shorter caudal hairs in the former species. The rostral process of the premaxillae is long (about equal to the height of I1) in zeledoni , but this process is much shorter (about half as long as I1 is tall) in robinsoni . The supraorbital ridges (described above for zeledoni ) are thicker and project laterally to a much greater extent in robinsoni , which sometimes develops distinct postorbital processes and has a more pronounced postorbital contriction (POC; tables 6, 7); the temporal ridges (which are subparallel in zeledoni ) converge posteriorly in mature adult specimens of robinsoni , sometimes forming a low sagittal crest. The auditory bullae, which are small and laterally compressed in zeledoni , are much larger and smoothly globular in robinsoni . A distinct notch separates stylar cusps D and E on M 2 in robinsoni , whereas this notch is absent in zeledoni .

Marmosa zeledoni differs from M. xerophila in the same characters that distinguish it from M. robinsoni , except that the rostral process of the premaxillae (long in zeledoni ) is completely absent in xerophila .

Marmosa zeledoni is, on average, larger in most measured external dimensions than M. simonsi , but it has absolutely and relatively smaller ears (tables 4, 5). In external characters, the two species differ conspicuously in dorsal fur color, which is a rich reddish brown in M. zeledoni versus distinctly grayish in M. simonsi . Whereas a continuous streak of pale self-colored fur extends from the chin to the anus in M. zeledoni , almost all of the ventral pelage is gray based in M. simonsi (only the chin and throat are self-colored). Additionally, the tail is entirely dark in M. zeledoni , but the distal half of the tail is whitish in M. simonsi . Cranial differences between these dissimilar forms include the rostral process of the premaxillae (long in zeledoni , short in simonsi ), postorbital processes (indistinct or absent in zeledoni , consistently well developed in simonsi ), palatine fenestrae (absent in zeledoni , present in simonsi ), and a distinct notch between stylar cusps D and E on M2 (absent in zeledoni , present in simonsi ).

Marmosa zeledoni is externally similar in size and coloration to the western Amazonian species M. rubra , from which it principally differs by lacking a dark median rostral stripe (present in rubra ), by possessing a gular gland (absent in rubra ), and in caudal morphology (the caudal scales of rubra are arranged in unambiguously spiral series and the central hair of each triplet is only about one scale long). Marmosa zeledoni is smaller, on average, than M. rubra in most craniodental dimensions (tables 6, 7), but there is broad overlap in all measurements, none of which is sufficient for identification purposes. Instead, M. zeledoni differs from M. rubra by having a preparacrista that connects to stylar cusp B (the preparacrista connects to stylar cusp A in rubra ), and by lacking a distinct notch between stylar cusps D and E (a distinct notch is present between these cusps in rubra ).

GEOGRAPHIC DISTRIBUTION AND SYM- PATRY: Based on positively identified specimens, Marmosa zeledoni occurs from northern Nicaragua (Río Coco, locality 60; fig. 21) southward through Costa Rica and Panama to southwestern Colombia (Candelilla, local- ity 176). Incomplete and/or immature material that we tentatively identify as M. zeledoni , however, includes a skin (AMNH 46682) from Gualea (locality 218) in the Pacific foothills of western Ecuador.

Marmosa zeledoni has been collected between 100 m and 2200 m above sea level, but it is apparently more abundant in montane or submontane habitats than it is near sea level: 72% of the collecting localities for which there is altitude information are above 700 m, and 61% are above 1100 m. These upland localities are mainly in the Cordillera Central and Cordillera de Talamanca of Costa Rica, the Chiriquí highlands of western Panama, and the Serranía del Darién of eastern Panama. Vegetation maps suggest that most specimens of Marmosa zeledoni are associat- ed with lowland or montane rain forests.

The range of Marmosa zeledoni partially overlaps that of M. mexicana , with which it sometimes occurs sympatrically as described in the preceding account of that species. The range of M. zeledoni also overlaps the range of M. isthmica from western Panama to southwestern Colombia, but the two species have been collected sympatrically only at San José (locality 185) in western Colombia. The range of M. zeledoni additionally overlaps that of M. robinsoni in Panama, where the two species have been sympatrically collected at Finca Santa Clara (locality 109) and near Escopeta Camp (locality 110).

GEOGRAPHIC VARIATION: Examined specimens exhibit variation in pelage color that appears to be correlated with elevation. Thus, skins from montane habitats in Panama tend to have darker, brownish dorsal fur and darker and more broadly gray-based ventral fur (the latter extending to the inner sides of the arms and legs); in this material, the graybased ventral fur is similar in color to the lateral body fur. By contrast, specimens from lowland habitats in Nicaragua, Costa Rica, and Colombia tend to have redder dorsal fur and paler and more narrowly distributed gray-based ventral fur (the latter not extending to the inner side of the arms and legs); in this material, the gray-based ventral fur is substantially paler than the lateral body fur.

TAXONOMIC HISTORY: The first published reference to material that we identify as Marmosa zeledoni was by Allen (1891), who misidentified specimens of this mouse opossum as Didelphys (Micoureus) murina . Conspecific Central American material was also misidentified (as M. murina or M. mexicana ) by subsequent authors, until Goldman (1911) described M. zeledoni based on five specimens from Navarro ( Costa Rica) and Escondido River ( Nicaragua). Allen (1912) treated zeledoni as a subspecies of M. murina , but Goldman (1917) allied zeledoni with M. mexicana , an opinion followed by most subsequent authors, including Tate (1933). Recent authors (e.g., Honacki et. al., 1982; Eisenberg, 1989; Alonso-Mejía and Medellín, 1992; Emmons, 1997; Reid, 1997; Nowak, 1999; Brown, 2004; Gardner, 2005) have consistently failed to recognize zeledoni as a valid taxon.

SPECIMENS EXAMINED (N 5 77): NICA- RAGUA —Without other locality data (USNM 361203, 361204). Atlántico Sur, Escondido River (USNM 36348, 50882). Jinotega, Río Coco (AMNH 29271), San Rafael del Norte (AMNH 28285). Matagalpa, El Tuma (5 Río Tuma: AMNH 29542), Vijagua (AMNH 29541). Río San Juan, San Carlos (5 La Esperanza: USNM 361194–361202). COSTA RICA — Cartago, Aquiares (AMNH 63999), Cerro Carpintera (5 La Carpintera: AMNH 3652), Navarro (USNM 12885 [holotype of Marmosa zeledoni Goldman, 1911 ]). Heredia, 11 km S and 4.5 km W Puerto Viejo (FMNH 128390, 128391, 128393, 128397, 128398), 11 km S and 11.5 km E San Miguel Angeles (FMNH 128400). Limón, Jiménez (AMNH 9593/ 7930). Puntarenas, Cerro Cañas Gordas (AMNH 142488, 142489), Coto Brus (5 Costa Brus: USNM 516606), Finca Helechales (USNM 547941, 547995, 547997–548000, 548003), Monteverde (FMNH 123992), San Jerónimo (5 San Geronomo: FMNH 35180). San José, Escazú (BMNH 3.2.1.10). PANA- MA— Bocas del Toro, Almirante (USNM 315001, 315003), Changuinola (USNM 315005–3150007), E of Cerro Pando (USNM 516605), Fish Camp (USNM 520691), Río Changena Camp (USNM 319372). Chiriquí, Bugaba (5 Bogava: BMNH 0.7.11.87– 0.7.11.89, 0.7.11.91, 0.7.11.92, 3.3.3.107), Casa Tilley (USNM 314188–314190), Cerro Fortuna (5 Reserva Florestal Fortuna: AMNH 269997), El Volcán (5 Volcán: AMNH 147759, 147760), Finca Santa Clara (5 Osta Clara: USNM 396509, 516603), Near Escopeta Camp (5 24 km NNE San Felix: USNM 541001, 541005, 541007, 541010, 541012, 541013, 541016, 541017). Darién, Cerro Malí (USNM 337954–337957), Cerro Tacarcuna (USNM 337958). COLOMBIA — Nariño, Candelilla (FMNH 89565). Valle del Cauca, San José (AMNH 31683).

OTHER SPECIMENS: In addition to material positively identifiable as Marmosa zeledoni , we examined 42 specimens that we provisionally refer to this species. Most of these are juveniles or subadults that have not developed all of the diagnostic traits that distinguish this species from M. isthmica , but a few are skins unaccompanied by skulls (e.g., AMNH 46682), and others are fluids from which skulls have yet to be extracted.

NICARAGUA — Atlántico Sur, Escondido River ( USNM 36349). COSTA RICA — Cartago, Navarro ( USNM 12884). Heredia, 11 km S and 4.5 km W Puerto Viejo ( FMNH 128389, 128395, 128396, 128399). Limón, Pandora ( USNM 284465). Puntarenas, Boruca ( AMNH 11794/10063), Monteverde ( FMNH 123993, 124100). PANAMA — Bocas del Toro, Almirante ( USNM 315002), Boca del Drago ( USNM 315004), N of El Volcán ( USNM 516948). Chiriquí, Near Escopeta Camp ( USNM 541003, 541004, 541006, 541008, 541009, 541011, 541014, 541015, 541018, 541325–541330, 541332, 541333), Finca Santa Clara ( USNM 539832). COLOMBIA — Cauca, San José ( AMNH 31694). ECUA- DOR— Pichincha, Gualea ( AMNH 46682).