Myotis handleyi, Moratelli & Gardner & Oliveira & Wilson, 2013

Moratelli, Ricardo, Gardner, Alfred L., Oliveira, João A. De & Wilson, Don E., 2013, Review of Myotis (Chiroptera, Vespertilionidae) from northern South America, including description of a new species, American Museum Novitates 2013 (3780), pp. 1-36 : 11-18

Myotis handleyi , sp. nov.

Handley’s Myotis

Figures 5–8 ; tables 5, 6

Myotis nigricans nigricans: LaVal, 1973:7 , part.

Myotis nigricans: Handley, 1976:36 , part.

Holotype: An adult male, USNM 370932 , with skin and skull, including mandible (figs. 7 and 8), collected by the Smithsonian Venezuelan Project team (Mammals Field Number 753), elevation 2092 m, on 19 August 1965. External and craniodental measurements for the type series and other specimens are provided in table 5.

Type Locality: Pico Ávila , 5 km northeast of Caracas, ca. 10.33°N, 66.52°W, Distrito Federal, Venezuela, elevation 2092 m .

Paratype: Adult male, USNM 370891 , collected by the Smithsonian Venezuelan Project team (Mammals Field Number 928), at the same locality as the holotype, elevation 2150 m, on 29 August 1965. The paratype consists of skin and cranium (mandible missing) .

Other Specimens: Additional specimens were collected in Venezuela from 1966 to 1986 by the Smithsonian Venezuelan Project in Monagas ( USNM 409391, USNM 409429–409431, 409433, 409435, 409437, 409438) and Miranda ( USNM 387723), and by C.O. Handley, Jr., and D.I. Rhymer ( USNM 517503) and A.L. Gardner and M. Candee, ( USNM 562923–562937) in Aragua.

Distribution: Myotis handleyi is known from two cordilleras in northern Venezuela. We have examined specimens from Distrito Federal (2092–2150 m) and the states of Monagas (1190 m), Aragua (1050–1100 m), and Miranda (1180 m). The Distrito Federal, Miranda, and Aragua localities are in the Cordillera de la Costa, and the Monagas locality is in the Macizo Oriental (fig. 9). We expect this species to be found in adjacent mountains such as the Serranía del Interior, Sierra de Aroa, Serranía de San Luis, and the Cordillera de Mérida (fig. 9). Anderson and Gutiérrez (2009) and Quiroga-Carmona and Molinari (2012) provide detailed descriptions of mountain ranges in northern Venezuela.

Diagnosis: The following set of traits distinguishes M. handleyi from all other South American congeners: dorsal fur long, silky, and bicolored with burnished tips; skull long, rostrum long and broad, and frontals moderately to steeply sloping; sagittal crest very low or absent; plagiopatagium broadly attached to the foot at the level of the base of the toes; fringe of hairs along the trailing edge of uropatagium absent; and fur on uropatagium not reaching knees.

Description: A medium-sized species of South American Myotis ( FA 33.7–37.3 mm, weight 3.5–6.0 g; table 5); with medium-sized ears (ear length 12–15 mm); relatively long, silky fur ( LDH: 6–9 mm, LVH: 5–7 mm); ventral fur strongly bicolored, with black bases (ca. 3/4 of the hair length) and Light-Buff tips (1/4); and dorsal fur moderately tricolored, with black bases (ca. 3/6 of the hair length), a central Mummy Brown band (ca. 2/6), and Antimony Yellow tips (ca. 1/6). This third (terminal) band is well defined in most individuals (e.g., USNM 370891, 409434, 409439), but can be difficult to see in others (e.g., USNM 409435, 409437, 409438). Membranes are Mummy-Brown. Skull small to moderate in size ( GLS 13.5–14.2 mm; BCB 6.1–6.6 mm); with the second upper premolar (P3) aligned in toothrow, smaller than P2 and P4, and visible in labial view, but crowded to the lingual side and barely visible in USNM 562934; sagittal crest usually absent, but low and weakly developed in USNM 562927; lambdoidal crests absent or when present, varying from very low to moderate in development; and occipital rounded and projecting behind the posterior surfaces of occipital condyles. External and cranial measurements are in tables 5 and 6.

Variation: Populations of M. handleyi apparently are confined to the Cordillera de la Costa (Aragua, Miranda, and Distrito Federal) and the Macizo Oriental (Monagas). Specimens from the Macizo Oriental are smaller than those from Cordillera de la Costa (table 6). Measurements related to length of cranium ( GLS, CCL, CBL, BAL) and rostrum ( MTL, M13), and width of rostrum ( BAC, BAM) prove statistically significant; whereas others related to cranial breadth ( ZB, MAB, BCB, IOB, POB) were not. The Cordillera de la Costa is separated from the Macizo Oriental by the Depresión de Unare, a gap of ca. 200 km of lowland dry forests. If M. handleyi proves to be restricted to the upper elevations, these differences may be indicative of distinct subspecies. Their relationship will be assessed when additional specimens become available.

Comparisons: Myotis handleyi can be distinguished from South American congeners by qualitative and quantitative traits. It differs from M. albescens and M. levis (I. Geoffroy, 1824) by the absence of a fringe of hairs along the trailing edge of the uropatagium; from M. keaysi , M. riparius , M. ruber (É. Geoffroy, 1806) , and M. simus by the silky dorsal fur and absence of sagittal crest. Myotis handleyi is also distinguished from M. keaysi by the fur on uropatagium not reaching the knees, and from M. simus by the plagiopatagium broadly attached at base of toes. Myotis handleyi can be distinguished from M. nesopolus , M. chiloensis (Waterhouse, 1840) , and M. lavali Moratelli et al., 2011a , by its less contrasting dorsal fur; also distinguished from M. nesopolus by its shorter dorsal fur and longer forearm, and from M. chiloensis and M. lavali by the darker dorsal fur and absence of sagittal crest. Myotis handleyi differs from M. oxyotus and M. izecksohni Moratelli et al., 2011a , by having shorter dorsal fur and a smaller skull; it is also distinguishable from M. oxyotus by its less steeply sloping frontals. Myotis handleyi can be distinguished from M. aelleni Baud, 1979 , by its smaller external and cranial dimensions; from M. atacamensis ( Lataste, 1892) and M. diminutus Moratelli and Wilson, 2011a , by its larger external and cranial dimensions; also distinguished from M. atacamensis by having a nearly naked dorsal surface of the uropatagium, and from M. diminutus by its broader skull ( M. handleyi : cranial index 70–85, maxillary index 22–25; M. diminutus : cranial index 59, maxillary index 17). Myotis handleyi can be distinguished from M. nigricans by the longer skull and broader rostrum, moderately sloping frontals, longer and darker dorsal fur with burnished tips, and whitish tips on the ventral fur (Light-Buff), in contrast to yellowish tips (Ochraceous-Buff) in M. nigricans .

The forearm and third metacarpal lengths, and the length and color of dorsal fur are the most useful traits when distinguishing M. handleyi from M. nigricans in the field. The absence of a fringe of hairs along the trailing edge of uropatagium, the silky, long (> 5 mm), and tricolored dorsal fur with burnished tips, and the forearm length (> 33 mm) are the most useful field traits for identifying M. handleyi from the remaining Venezuelan and Colombian species. Nevertheless, we recommend examination of skulls for unequivocal identification.

Etymology: Myotis handleyi honors the late Charles O. Handley, Jr., in recognition of his outstanding contributions to South American chiropterology. Handley, with V.J. Tipton, coordinated the consortium of scientists who studied the distribution and ecology of mammalian ectoparasites, arboviruses, and their hosts in Venezuela from 1965 to 1968, in an initiative called the Smithsonian Venezuelan Project. These collections are the basis for more than 50 papers on Venezuelan mammals and their parasites ( Handley, 1976).

Natural History: One pregnant, nine lactating, and one postlactating females were caught in May 1986 as they emerged from crevasses in an outside wall at the Rancho Grande Biological Station, which is located in humid forest. Specimens from Distrito Federal and Monagas also were caught in humid forest habitat .

Figures

FIG. 5. Dorsal, ventral, and lateral views (scale bar = 5 mm) of skulls of specimens from A, upper elevations in Venezuela (USNM 370891; subsequently assigned to M. handleyi); B, Colombia (AMNH 32787; subsequently assigned to M. caucensis); and C, lower elevation in Venezuela (USNM 373929; M. nigricans). See table 4 for measurements.

FIG. 6. Dorsal (A–C) and ventral (D–F) views of skins of specimens from upper elevations in Venezuela (A and D—USNM 370891; subsequently assigned to M. handleyi), and Colombia (B and E—AMNH 461860; subsequently assigned to M. caucensis), and lower elevation in Venezuela (C and F—USNM 373925; M. nigricans). See table 4 for measurements.

FIG. 7. Dorsal (A) and ventral (B) views of the skin of the holotype of Myotis handleyi (USNM 370932; scale bar = 10 mm). On the right side enlarged views of the dorsal (C) and ventral (D) pelage, highlighting the contrast between bases and tips. See table 5 for measurements.

FIG. 8. Dorsal, ventral and lateral views (scale bar = 5 mm) of the cranium and lateral view of the mandible of the holotype of Myotis handleyi (USNM 370932). See table 5 for measurements.