The identity of Myotis punensis ( Chiroptera : Vespertilionidae )

Currently twelve species of Myotis Kaup, 1829 (Vespertilionidae: Myotinae) are recognized from South America, with several other named taxa regarded as synonyms, among them Myotis punensis J.A. Allen, 1914. This name was first regarded as a junior synonym of Myotis albescens (E. Geoffroy, 1806) and subsequently of Myotis nigricans (Schinz, 1821). To address the taxonomic status of the holotype of M. punensis, we compared it to all South American species in the genus. The fringe of hairs on the trailing edge of the uropatagium, the fur color, and external and skull dimensions all suggest M. punensis should be treated as a junior synonym of M. albescens

Myotis Kaup, 1829 (Vespertilionidae: Myotinae) comprises a diverse group of small to large-sized vespertilionid bats with a worldwide distribution, including more than one hundred species (SIMMONS 2005).Twelve South American species are recognized currently (WILSON 2008).Nevertheless, about 60 names have been proposed for South American Myotis since the description of the first species from that continent, Myotis albescens (É.Geoffroy, 1806), more than two centuries ago.Among them, Myotis punensis J.A. Allen, 1914 was described based on a single specimen from Isla Puna, Ecuador.MILLER & ALLEN (1928) regarded the name Myotis punensis as a junior synonym of Myotis albescens.Later LAVAL (1973) identified the holotype of M. punensis as M. nigricans (Schinz, 1821).LAVAL (1973) applied the name Myotis punensis to populations of M. nigricans from lowland localities on the west side of the Andes in Colombia, Ecuador, and Peru, recognizing them at the subspecific level as M. nigricans punensis J.A. Allen, 1914. Subsequently, BOGAN (1978) refuted the distinctness of those populations and recommended that the name Myotis nigricans punensis should be relegated to the synonymy of Myotis nigricans nigricans, but without examining the holotype of M. punensis.BOGAN'S (1978) suggestion was followed by SIMMONS (2005) and WILSON (2008), who considered Myotis punensis a junior synonym of Myotis nigricans.
As part of an ongoing systematic and biogeographic review of South American species of Myotis and in order to further investigate the identity of M. punensis, we compared its holotype with the South American species of Myotis currently recognized.

MATERIAL AND METHODS
We evaluated the taxonomic status of M. punensis by comparing its holotype (AMNH 36263) to the currently recognized South American species of Myotis, represented by their type specimens, original descriptions, redescriptions provided by LAVAL (1973) and comparative series from different localities.The type specimens used in comparisons were: M. albescens (AMNH 205195, neotype), M. levis levis (I.Geoffroy, 1824) (MNHN type no.203, lectotype), M. keaysi keaysi J.A. Allen, 1914 (AMNH 15814, holotype), M. nesopolus larensis LaVal, 1973 (AMNH 130709, holotype), M. riparius Handley, 1960 (USNM 310255, holotype) and M. ruber (É.Geoffroy, 1806) (USNM 115097, neotype).The original descriptions used in comparisons were: M. aelleni Baud, 1979, M. atacamensis (Lataste, 1892), M. chiloensis (Waterhouse, 1840), M. levis dinellii (Thomas, 1902), M. keaysi pilosatibialis LaVal, 1973, M. nigricans nigricans (Schinz, 1821), M. oxyotus (Peters, 1867) and M. simus Thomas, 1901.A list of specimens examined and their localities is in the Appendix 1.A set of qualitative and quantitative characters reported as diagnostic by previous authors (THOMAS 1901, 1902, MILLER & ALLEN 1928, HANDLEY 1960, LAVAL 1973, BAUD & MENU 1993, LÓPEZ-GONZÁLEZ et al. 2001, LÓPEZ-GONZÁLEZ 2005, WILSON 2008) were used in comparisons.The qualitative characters selected were: plagiopatagium attachment (attached at ankles; at toes by a narrow band of membrane; or at toes by a broad band of membrane); occurrence of a fringe of hairs along the trailing edge of the uropatagium (absent or present); position of P3 (aligned with other premolars or displaced to the lingual side, and visible or not visible when observed in lateral view); occurrence and height of sagittal and occipital crests (absent or present; and height: very low, low, medium and high); shape of the braincase roof (parietal inclined forward or straight when observed in lateral view); shape of the supraoccipital region (supraoccipital and posteriormost part of parietals flattened when observed in lateral view, not projecting much beyond the limit of the occipital condyles, or supraoccipital and
Nine cranial and four external dimensions were measured using a digital caliper accurate to 0.02 mm.The measurements, reported in millimeters (mm), and their abbreviations are defined as follows (lengths were measured from the anteriormost point of the first structure to the posteriormost point of the second structure mentioned below): zygomatic breadth, greatest breadth across the outer edges of the zygomatic arches; interorbital breadth, least breadth dorsally between the orbits; postorbital breadth, least breadth across frontals posterior to the postorbital bulges; breadth across canines, greatest breadth across outer edges of the crowns of upper canines including cingulae; breadth across molars, greatest breadth across outer edges of the crowns of upper molars; maxillary toothrow length, from the upper canine crown including cingulum to the crown of M3; molariform toothrow length, from the crown of M1 to the crown of M3; mandibular length, from the line of internal incisors, to the angular process; mandibular toothrow length, from the lower canine to m3; forearm length, from the elbow to the distal end of the forearm including carpals; third metacarpal length, from the distal end of the forearm to the distal end of the third metacarpal; and length of the dorsal and ventral hairs, from the base to the tip of the hair, measured between scapulas.Other measurements that characterize the length of skull were not used due the condition of the skull, which lacks parts of the posterior region.
The holotype is a small specimen (forearm length 31.6 mm) with small ears (less than 12 mm) and long, silky pelage (length of dorsal fur 7.3 mm; ventral fur 5.4 mm).The dorsal fur is distinctly bicolored with medium-brown bases (more than 2/3 of total length) and light-brown tips.The ventral fur is strongly bicolored with dark-brown bases (2/3 of total length) and yellow tips.There is more contrast between bases and tips in the ventral fur than in the dorsal fur.The membranes are medium brown and there is a weak fringe of hairs along the trailing edge of the uropatagium.The plagiopatagium appears to be attached at feet (Fig. 1).The skull is small (mandibular length 9.04 mm) and the braincase is long and flattened.The supraoccipital region is rounded and the sagittal crest is very low.There are no occipital crests and the third upper premolar is in the toothrow, not crowded to the lingual side (Fig. 2).
Based on external and skull measurements reported by LAVAL (1973) and LÓPEZ-GONZÁLEZ et al. (2001) for South American Myotis, the holotype of M. punensis overlaps in size with specimens of M. atacamensis, M. nigricans and M. albescens among its South American congeners (LAVAL 1973).Myotis punensis can be distinguished from the species above, except M. albescens, based on the fringe of hairs along the trailing edge of the uropatagium, a character shared only by M. albescens and M. levis among South American Myotis (LAVAL 1973, WIL-SON 2008).Although some hairs may be present along the edge of the uropatagium in some specimens of M. nigricans and M. oxyotus, they do not form the fringe observed in M. albescens and M. levis.The holotype of M. punensis can be distinguished from M. levis primarily by its smaller overall size, smaller ears (ranging from 12-19 mm in M. levis) and lighter ventral fur coloration.In addition, M. levis is reported only from Bolivia, Argentina, Uruguay, and Brazil, occurring from 20°S toward southward (LAVAL 1973, SIMMONS 2005, WILSON 2008).On the other hand, some of the main diagnostic characters in M. albescens are the ear length (9-14 mm), long and silky pelage, tips of dorsal pelage with frosted appearance, and fringe of hairs along the trailing edge of uropatagium (LAVAL 1973, LÓPEZ-GONZÁLEZ et al. 2001, BRAUN 2009), all of which are present in the holotype of M. punensis.Additionally, M. albescens is widely distributed in South and Central America.ALLEN (1914) described M. punensis as smaller but similar in coloration to M. albescens.Subsequently, MILLER & ALLEN (1928) considered M. punensis a junior synonym of M. albescens.On the other hand, LAVAL (1973) regarded M. punensis as a subspecies of M. nigricans.Subsequently, BOGAN (1978) regarded M. punensis as a junior synonym of M. nigricans, a decision followed by SIMMONS (2005) and WILSON (2008).In this study, based on overall external and skull size, tips of dorsal pelage with frosted appearance and presence of a fringe of hairs along the trailing edge of the uropatagium in the holotype of M. punensis, we suggest that the name Myotis punensis J.A. Allen, 1914 should be regarded as a junior synonym of Myotis albescens (É.Geoffroy, 1806), as formerly proposed by MILLER & ALLEN (1928).

DISCUSSION
We did not examine other specimens assigned to M. n. punensis by LAVAL (1973).BOGAN (1978), however, did analyze part of the Colombian and Ecuadorian samples assigned to M. n. punensis by LAVAL (1973).Based on a multivariate analysis of cranial and external morphology, BOGAN (1978) refuted the distinctness of those samples in relation to other South American samples of M. nigricans.Based on BOGAN's (1978) results other specimens assigned to M. n. punensis by LAVAL (1973) probably are M. nigricans.Despite the conclusions of LAVAL (1973) and BOGAN (1978), if those populations on the west side of the Andes ultimately should prove to be distinct from populations assigned to M. nigricans nigricans by LAVAL (1973), as well as from other currently recognized South American species, the name Myotis punensis J.A. Allen, 1914, is not available for them, as it is a junior synonym of Myotis albescens (É.Geoffroy, 1806).A possible name for those populations is Myotis esmeraldae J.A. Allen, 1914, a name currently in the synonymy of Myotis nigricans.

ACKNOWLEDGEMENTS
The following curators and collection staff provided access to specimens under their care: Adriano L. Peracchi (Universidade Federal Rural do Rio de Janeiro, Brazil), João Alves de Oliveira, Stella M.

1
Figure 1.Dorsal and ventral views of the skin of the holotype of Myotis punensis (AMNH 36263).Forearm length 31.6 mm.The electronic version of this article includes this figure in color.2 1

Figure 2 .
Figure 2. Dorsal, ventral and lateral views of the cranium and dorsal and lateral views of the mandible of the holotype of Myotis punensis (AMNH 36263).See text for measurements.