AMERICAN MUSEUM NOVITATES

Number 3798: 31 pp. April 4, 2014

Copyright © American Museum of Natural History 2014

ISSN 0003-0082

Quaternary Bats from the Impossível-Ioiô Cave System (Chapada Diamantina, Brazil): Humeral Remains and the First Fossil Record of Noctilio leporinus (Chiroptera, Noctilionidae) from South America

LEANDRO O. SALLES,[1], [2] JOAQUÍN ARROYO-CABRALES,[3] ANNE CARULINY DO MONTE LIMA,[4] WAGNER LANZELOTTI,[5] FERNANDO A. PERINI,[6] PAÚL M. VELAZCO,[7] AND NANCY B. SIMMONS[8]

ABSTRACT

The partially submerged Impossível-Ioiô cave system located in the karst region of Chapada Diamantina in Bahia (Brazil) has recently been the target of extensive paleontological studies. Here we provide the first report of fossil bats from this cave system, in which we recognize six species based on humeral remains: Furipterus horrens, Chrotopterus auritus, Mormoops cf. megalophylla, Pteronotus gymnonotus, Pteronotus parnellii, and Noctilio leporinus. Morphology of the humerus of these taxa is described in a comparative framework to document taxonomic assessments and provide a basis for future studies of fossil bat faunas. The relevance of the new records reported here is evaluated at a broader continental scale, as well as in contrast with the recent bat fauna of the region. The record of Noctilio leporinus stands as the first fossil occurrence of this species on the South American continent.

INTRODUCTION

The Chapada Diamantina plateau, located in the state of Bahia and extending northeast of the Espinhaço mountain chain, is one of the most important karst areas in Brazil (fig. 1). The north-central region of the plateau is well known for its many caves, some of which are filled by crystal waters and most of which remain unexplored, with great potential for geopaleontological studies. During the last few years we have carried out extensive paleontological research in this region centered on the Impossível-Ioiô cave system and focused on underwater Quaternary deposits rich in fossil mammals. A variety of small and medium-sized mammals have been found in this system and, aside from a skeleton of †Nothrotherium sp. (Xenarthra: Nothrotheriidae) (Perini et al., in prep.), all of the records represent extant taxa. This contribution is the first report describing the bat paleofauna recovered from the Impossível-Ioiô, which is the fifth site with bat remains known for the Chapada Diamantina plateau (Cartelle and Abuhid, 1994; Czaplewski and Cartelle, 1998).

Previous knowledge of the bat paleofauna of the Quaternary of Chapada Diamantina is based on reports by Cartelle and Abuhid (1994) and Czaplewski and Cartelle (1998), who summarized data from four caves (fig. 1): Toca da Boa Vista (10°09′36.72″S, 40°51′38.88″W), Toca da Barriguda (10°08′26.88″S, 40°51′07.92″W), Gruta dos Brejões (10°59′10.32″S, 41°25′59.52″W), and Toca dos Ossos (10°55′49.44″S, 41°03′27.36″W). Czaplewski and Cartelle (1998) proposed a formal time reference based on a sample of Mormoops megalophylla from Toca da Boa Vista that was radiocarbon dated at approximately 20,000 years BP. Toca da Boa Vista, the largest cave in Brazil, preserves by far the most diverse regional bat paleofauna with 19 species records, followed by Gruta dos Brejões with 10 bat species. Only one of the 27 taxa recovered from this set of caves is extinct: †Desmodus draculae, the giant vampire bat.

The paleofauna of bats from Chapada Diamantina is addressed here in the context of the new records from Impossível-Ioiô, including the first Quaternary records of Noctilio leporinus from South America. This first report is exclusively based on humeral remains, which are diagnostic at the species level in Chiroptera (see below); other osteological data will be presented in a planned series of additional contributions on the fossil bats from this region. The relevance of the new records reported here is evaluated at a broader continental scale, as well as in contrast with the recent bat fauna of the region (e.g., Sbragia, 2012). The current study contributes to ongoing efforts to shed new light on the Pleistocene/Holocene bats of the South American continent, and more specifically to better understand the evolution of faunas of the unique karst region of northeastern Brazil, currently covered by semiarid savannas within the Caatinga domain.

MATERIAL AND METHODS

Study Area and Geological Background

The Ioiô-Impossível (12°23′13.56”S, 41°32′57.48”W) is a large cave system located in the Iraquara karst region (Laureano and Cruz, 2002; Laureano, 1998; Cruz, 1998) (fig. 1), a subunit of the Precambrian carbonate rocks of the Ulna Group (Auler and Farrant, 1996) situated in the geologically well-known Irecê sedimentary basin (Souza et al., 1993). Paleontological explorations carried out in this cave have been concentrated on the main ducts, which are partially filled with water. These ducts can be accessed via the Impossível main entrance, which is situated at the bottom of a collapsed sinkhole that is oval in shape and approximately 100 m in diameter and 50 m in height (fig. 2). The cave ducts are partially filled by sediments that contain concentrations of fossil vertebrate bones in some locations, mostly medium-sized animals such as carnivores (Felidae, Procyonidae, Mustelidae) and xenarthrans (Dasypodidae, Myrmecophagidae).

Many of the medium-sized and larger specimens found in the bone concentrations are disarticulated, but nearly all are spatially arranged in such way that they seem to have maintained, at least to some extent, their anatomical relationships. This suggests that very little bone displacement occurred after the death of these animals, which in turn implies that the flux of water and sediments has been very slow and without sufficient energy to disperse larger bones along the cave ducts. A complete analysis of the taphonomy of these fossils will be the subject of another work, but the most likely hypothesis is that these nonvolant animals fell into the cave system via skylights, small holes, and fissures (all present in the area) that can function as pitfalls, and that they were preserved near where they died or their carcasses came to rest (Hubbe et al., 2011). In contrast, the isolated microvertebrate remains recovered in the cave system do not present evidence of the conditions described above, seeming instead to have been accumulated as a mix of disarticulated bones in certain areas in the cave. Some coincide with the sites of accumulation of medium-sized mammals, while others are dispersed along the ducts of the cave system. The microvertebrate fauna thus preserved includes bats, rodents, and marsupials, as well as lizards and frogs. Regardless of how they entered the cave, many of the microvertebrates apparently were disarticulated and their bones transported after decomposition.

Two areas with concentrations of bones of small mammals were selected for sampling (fig. 3), and the one that was most intensively sampled was the site where a skeleton of †Nothrotherium sp. (Xenarthra, Nothrotheriidae) was found. The latter specimen represents the only source of age reference for these fossils thus far. At Beta Analytic Inc. (http://www.radiocarbon.com) significant amounts of collagen were successfully extracted from bone samples for AMS radiocarbon dating of the †Nothrotherium specimen, with a resulting date of 8700 ± 50 years BP (Perini et al., in prep.).

The Nothrotherium site covers an area of approximately 10 m2 on the bottom of one of ducts that connects the main entrance of the Impossível cave, approximately 280 m from the entrance. A cross section of the so-called Nothrotherium duct is illustrated in figure 3 along with a sequence of photos that document the major passages of the duct. The Nothrotherium site is oval in shape, submerged in a water column of approximately 8 m (depth apparently not significantly varying between dry and rainy seasons) with lateral walls separated by about 5 m. In one of the walls, laminar carbonate concretions are present at different depths, some close to the bottom level, which is covered by silt, clay, and sand grains. In order to collect microvertebrate remains associated with these submerged sediments, some of the established quadrants were collected by using a pressurized air-suction device or airlift (Salles et al., 1999). Sediments containing fossil fragments were sucked through a pipe that ended at a sequence of sieves of different square mesh sizes varying from 0.2 to 1.2 cm. A sequence of schematic illustrations (fig. 3a–c) shows how the airlift system was used at the Impossível-Ioiô cave system. Small samples of fossils were also collected by hand with the use of surgical gloves and plastic zip bags. All remains representing the order Chiroptera were manually sorted from mixed packages of microvertebrate bones.

FIGURE 1. Map illustrating northeastern Brazil. Light gray shading indicates the extent of the Caatinga Biome, dark gray the Serra do Espinhaço mountains, and medium gray shading shows the extent of the Serras da Diamantina plateau. Numbers indicate locations of caves from which fossil bats have been collected: 1, Toca da Boa Vista; 2, Toca da Barriguda; 3, Gruta dos Brejões; 4, Toca dos Ossos; and 5, the new fossil site Ioiô-Impossível.

FIGURE 2. Photograph showing one of the openings of the Ioiô-Impossível cave system as viewed from the top edge of the sinkhole. The main opening to the “Nothrotherium duct” is indicated by a dashed arrow.

FIGURE 3. Cross section of the “Nothrotherium duct” with schematics showing the airlift system used to collect fossils of microvertebrates including bats: (A) air-compression system placed at the cave entrance; (B) sieve system; and (C) at the Nothrotherium grid, a diver operating the pipe end with valve control for the air injection, which sucks water and sediments through the main pipe to the sieve system. Photographs below show images of the “Nothrotherium duct”: (D) dry area approximately 50 m from the entrance; (E) waterlogged portion approximately 150 m from the entrance; and (F) underwater view of the Nothrotherium grid.

Table 1. Measurements of humeri of fossil bats from the Impossível-Ioiô cave system. Measurements follow standards described by Czaplewski and Cartelle (1998) and are in mm.

Abbreviations are as follows: MN, Museu Nacional (Rio de Janeiro) catalog number; ch, complete humerus; ps, proximal end of humerus with shaft; p, proximal end only; ds, distal end of humerus with shaft; d, distal end only; TL, total length; SD, shaft diameter; WP, width of proximal end of humurus; WD, width of distal end of humerus; *, measurement approximate due to damage.

MN

Species

Description

TL

SD

WP

WD

57400

Noctilio leporinus

ch

39.94

2.52

6.37

6.66

57401

ch

39.13

2.51

5.95

6.43

57402

Mormoops cf. megalophylla

ch

31.45

1.8

3.94

4.26

57403

ch

31.76

1.87

4.07

4.57

57404

ps

–

1.81

4.05

–

57405

ps

–

1.94

4.12

–

57406

ch

31.14

1.74

4.07

4.45

57407

ch

30.74

1.8

4.08

4.17

57408

ds

–

1.81

–

4.59

57409

ds

–

1.67

–

3.62

57410

ps

–

1.77

4.05

–

57411

Pteronotus gymnonotus

ch

26.72

1.46

3.82

3.68

57412

ds

–

1.43

–

3.87

57413

ch

28.55

1.53

3.95

3.84

57414

ds

–

1.37

–

3.68

57415

ds

–

1.37

–

3.76

57416

ps

–

1.46

3.9

–

7417

p

–

–

3.59*

–

57418

Pteronotus parnellii

ds

–

1.54

–

4.45

57419

d

–

–

–

4.35

57420

ch

31.49

1.76

4.19

4.3

57421

ch

29.44

1.58

4.14

4.57

57422

ch

31.13

1.54

3.4*

4.51

57423

ch

31.75

1.55

4.16

4.43

57424

ch

30.3

1.53

4.03

4.38

57425

d

–

–

–

3.39*

57426

ps

–

1.41

4.15

–

57427

ds

–

1.41

–

4.16

57428

ch

30.45

1.51

3.57

3.07*

57429

Furipterus horrens

d

–

–

–

2.63

57430

Chrotopterus auritus

ch

45.71

3.05

7.07

9.75

Table 2. Quaternary bat records from the Chapada Diamantina region compared with the extant records from the region and Quaternary records from elsewhere in the Neotropics.

Abbreviations and data sources as follows: CD, Chapada Diamantina Plateau, Bahia (Quaternary: Czaplewski and Cartelle, 1998; extant: Sbragia, 2012); LS, Lagoa Santa, Minas Gerais (Lund, 1840; Winge, 1892; Paula Couto, 1946); SM, Serra da Mesa, Goiás (Fracasso and Salles, 2005); RRV, Ribeira River Valley, São Paulo (Trajano and de Vivo, 1991; Ameghino, 1907); Ga/Sa, Garivaldino and Sangão sites, Rio Grande do Sul (Hadler et al., 2010); Caa, bat records from the Caatinga Biome that occurs in the Chapada Diamantina Plateau (Sá-Neto and Marinho-Filho, 2013); SA, South America, excepting Brazil (Morgan et al., 1988; Pardiñas and Tonni, 2000; Czaplewski et al., 2005); CA, Central America and Caribbean (Reynolds et al., 1953; Choate and Birney, 1968; Silva-Taboada, 1974, 1979; Olson et al., 1990; Arroyo-Cabrales and Polaco, 2008; Olson and Nieves-Rivera, 2010; Orihuela, 2012; Velazco et al., 2013); NA, North America (Mexico only) sites (Arroyo-Cabrales and Polaco, 2008); *, data from current work; **, first record for area.

Brazil

SA

CA

NA

Quaternary

Extant

Quaternary

CD

LS

SM

RV

Ga/Sa

CD

Caa

FAMILY MORMOOPIDAE

Mormoops megalophylla

+*

+

+

+

Pteronotus davyi

+

+

+

Pteronotus gymnonotus

+**

+

+

+

Pteronotus parnellii

+*

+

+

+

+

+

FAMILY NOCTILIONIDAE

Noctilio leporinus

+**

+

+

+

FAMILY PHYLLOSTOMIDAE

Artibeus planirostris

+

+

+

+

+

+

Carollia perspicillata

+

+

+

+

Chrotopterus auritus

+*

+

+

+

+

+

+

+

+

†Desmodus draculae

+

+

+

+

+

Desmodus rotundus

+

+

+

+

+

+

+

+

Diphylla ecaudata

+

+

+

Lonchophylla mordax

+

+

+

Mimon bennettii

+

+

+

Phyllostomus discolor

+

+

+

+

+

Phyllostomus hastatus

+

+

+

+

+

+

Tonatia bidens

+

+

+

FAMILY FURIPTERIDAE

Furipterus horrens

+*

+

FAMILY VESPERTILIONIDAE

Eptesicus fuscus

+

+

+

+

+

+

FAMILY MOLOSSIDAE

Eumops perotis

+

+

+

+

+

Molossus molossus

+

+

+

+

+

Nyctinomops macrotis

+

+

+

Promops nasutus

+

+

Tadarida brasiliensis

+

+

+

+

+

TOTAL SPECIES

23

8

7

2

4

11

18

12

10

9

Specimen Identification

The fossils collected were deposited at the mammal section of the Museu Nacional–Universidade Federal do Rio de Janeiro. Identifications were based on literature descriptions and comparisons with extant specimens in the mammal collections of the Museu Nacional, Universidade Federal do Rio de Janeiro (MN); American Museum of Natural History, New York (AMNH); and Instituto Nacional de Antropología e Historia, México City (INAH) (appendix 1).

Standard measurements for the fossil humeri collected are presented in table 1. All specimens whose measurements are provided here were considered adults based on epiphyseal fusion. The terminology used for humerus morphology was standardized based on a modified version of that proposed by Czaplewski et al. (2008) (fig. 4). A comparative study of humeral morphology of Noctilio is provided in an attempt to reveal patterns of variation within the genus that could be used to identify fossils without relying exclusively on size.

FIGURE 4. The terminology used to describe humerus morphology (modified from Czaplewski et al., 2008) with proximal ends at the top and distal ends at the bottom of the figure. Letters are indicated on a posterior view (left) and anterior view (right) of a left humerus of Noctilio leporinus (MN 47199): a, head; b, greater tuberosity (= trochiter); c, lesser tuberosity (= trochin); d, pectoral ridge; e, medial ridge; f, epitrochlea, the region located medial to the trochlea and including both the medial process and spinous process; g, medial process; h, spinous process; i, radial fossa; j, lateral ridge of capitulum; k, medial ridge of capitulum; l, trochlea.

TAXONOMIC ACCOUNTS

A total of 33 humeral fragments of bats were recovered from the Impossível-Ioiô cave system. Six species from four families were identified based on this collection (table 2, appendix 2). Craniodental data will be addressed in a future publication. Taxonomic accounts for each family are provided below.

Family Furipteridae Gray, 1866

A distal end of a left humerus from Impossível-Ioiô is identified as Furipterus horrens (fig. 5), which represents the second fossil record for the species and the third for the family (Czaplewski and Cartelle, 1998; Morgan and Czaplewski, 1999). The first known fossil record of F. horrens (a left mandible and four humeri fragments) is also from the Quaternary of the Chapada Diamantina (Toca da Boa Vista; Czaplewski and Cartelle, 1998). The Chapada Diamantina records are consistent with the present distribution of the species, which ranges from Costa Rica to northeastern Brazil (Simmons, 2005; Peracchi et al., 2011), although it is considered a rare species and is difficult to collect with mist nets (Simmons and Voss, 1998; Bredt et al., 1999).

The humerus fragment from Impossível-Ioiô preserves only a small portion of the shaft with a damaged distal end. The dimensions of this specimen (table 1) fall well within the range of variation previously reported for Furipterus horrens (Czaplewski and Cartelle, 1998). Distal morphology of the humerus of F. horrens is distinct from that of other bats of comparable size, including thyropterids, natalids, emballonurids, and vespertilionids. The distal surface of the epitrochlea in F. horrens has a unique rounded and concave shape, with the anterolateral border extending over the anterior portion of the trochlea. The humerus in natalids such as Natalus stramineus resembles to a certain degree the general pattern found in Furipterus. However, Furipterus has a considerably larger and thicker trapezoidal spinous process, located directly adjacent to the posterior surface of the trochlea (fig. 6A), differing this way from natalids, but somewhat similar patterns are also observed among vespertilionids. This similarity in position with respect to the medial-lateral axis contrasts with significant differences in shape and direction of growth of the spinous process compared to that in vespertilionids, which display a markedly more posterior projection. The typical natalid medial extension of the posterior surface of the epitrochlea is entirely absent in F. horrens (b′ in fig. 6).

Extension of the posterior surface of the lateral ridge of the capitulum over the lateral border of a well-developed radial fossa (preserved in the fossil) is a character that unequivocally distinguishes Furipterus horrens from both natalids (c/c′ in fig. 6) and thyropterids, although this condition is also present in other bat lineages, such as emballonurids and noctilionids. These two lineages, however, have a very different overall pattern of distal morphology, mostly in shape and degree of development of the trochlea and the spinous process, which is relatively elongated and detached from the trochlea in both families.

FIGURE 5. Posterior and anterior views of a distal portion of the right humerus of Furipterus horrens (MN 57429). Scale bar = 1mm.

FIGURE 6. Differences in distal humeral morphology between Furipterus horrens (left) and Natalus stramineus (right) as seen in anterior view with lateral toward the right side of the figure; see text for discussion: (a/a′) shape and development of the spinous process (larger and more trapezoidal in Furipterus); (b/b′) development of the epitrochlea (less expanded mediolaterally in Furipterus); and (c/c′) development of the posterior surface of the lateral ridge of the capitulum (posterior surface expanded over the lateral border of a well-developed radial fossa in Furipterus).

Family Phyllostomidae Gray, 1825

The family Phyllostomidae is represented by humeral remains at Impossível-Ioiô by only one species, Chrotopterus auritus (fig. 7). The Pleistocene/Holocene records of this species are limited to reports from the Yucatán Peninsula of México (Arroyo-Cabrales and Alvarez, 1990), from Sierra de Perijá in Venezuela (Rincón, 1999), and from the following localities in Brazil: Lagoa Santa, Minas Gerais (Winge, 1892); Iporanga, São Paulo (Ameghino, 1907); Chapada Diamantina, Bahia (Cartelle and Abuhid, 1994; Czaplewski and Cartelle, 1998); Serra da Mesa, Goiás (Fracasso and Salles, 2005); and Brochier, Rio Grande do Sul (Hadler et al., 2010). These records include cranial and postcranial remains and are biogeographically consistent with the known extant distribution pattern of the species (Simmons, 2005).

The new record of Chrotopterus auritus from Chapada Diamantina consists of a single well-preserved right humerus that lacks only portions of the pectoral ridge and the tip of the spinous process (fig. 7). This specimen is the size and shape typical for the species. The shaft is arched with a concave curvature toward the middistal portion (viewed from the lateral side), and also exhibits torsion of this portion toward the medial side. This morphology also occurs in Vampyrum spectrum as well as in other phyllostomines such as Trachops cirrhosus and Tonatia saurophila. The proximal end of the humerus in Chrotopterus auritus and Vampyrum spectrum are very similar. In both species the humerus has a nearly spherical humeral head and a lesser tuberosity that is either similar in size or a bit larger than the greater tuberosity (Chrotopterus) or a lesser tuberosity that is distinctly larger than the greater tuberosity (Vampyrum) (fig. 8). Chrotopterus has a humerus with a distal end that is slightly less robust than in Vampyrum, with a less well-developed radial fossa and an overall smaller epitrochlea. The epitrochlea has an elongated shape, narrowing toward the medial end with a somewhat triangular distal surface (associated with the median process), a condition shared by Vampyrum and other phyllostomids. Nevertheless, it is anteroposteriorly wider in Vampyrum compared to the condition observed in Chrotopterus (b/b′ in fig. 8). The spinous process in Chrotopterus is small, located near the medial end of the epitrochlea, and has a trapezoidal shape quite different from the lower and wider process seen in Vampyrum (a/a′ in fig. 8). The degree of development of the trochlea also distinguishes these two species, being considerably wider and expanded over the epitrochlea surface in Vampyrum (c/c′ in fig. 8). The sister-taxon relationship found between Chrotopterus and Vampyrum in recent phylogenies (Wetterer et al., 2000; Baker et al., 2003; Dávalos et al., 2012) seems unquestionably supported by the patterns of variation in the humerus morphology seen in the family Phyllostomidae.

FIGURE 7. Anterior, posterior, lateral, and medial views of a right humerus of Chrotopterus auritus (MN 57430). Scale bar = 1mm.

FIGURE 8. Differences in distal humeral morphology between Chrotopterus auritus (left) and Vampyrum spectrum (right) as seen in anterior view with lateral toward the right side of the figure; see text for discussion: (a/a′) shape and development of the spinous process (smaller and more trapezoidal in Chrotopterus); (b/b′) anteroposterior development (width) of the epitrochlea (narrower in chrotopterus); and (c/c′) degree of the development of the trochlea (narrower and less expanded over the epitrochlea in Chrotopterus).

Family Mormoopidae Saussure, 1860

The family Mormoopidae is represented by a set of 27 humeral fragments identified as Mormoops cf. megalophylla (fig. 9), Pteronotus gymnonotus (fig. 11), and P. parnellii (fig. 12). The record of Mormoops is particularly noteworthy because these bats do not occur in the region today, instead having a distribution that is primarily limited to Central America and the Caribbean, with a very restricted range in northwestern South America (Simmons, 2005). The presence of the genus in the Quaternary of Chapada Diamantina was previously reported by Cartelle and coauthors (Cartelle and Abuhid, 1994; Czaplewski and Cartelle, 1998) based on craniodental remains as well as a number of humeri (although only measurements of a subset of 54 were provided). Those authors tentatively identified all of these fossils as Mormoops megalophylla, although they also suggested that, based on their large size, they might represent †M. magna, an extinct species exclusively known from humeri remains from Cuba and the Dominican Republic (Silva Taboada, 1974; Jiménez Vázquez et al., 2005; Velazco et al., 2013).

The new records of Mormoops recovered from the Impossível-Ioiô cave system consist of nine humeral fragments, four of which are complete and all of which we assign to Mormoops cf. megalophylla. These are unquestionably Mormoops, but biogeographic considerations and lack of comprehensive analyses of variation within the genus suggests that caution should be used in assigning them to M. megalophylla. The Chapada Diamantina fossils of Mormoops have a morphology very much like that of M. megalophylla, but they are slightly more robust than typical extant specimens, as pointed out by Czaplewski and Cartelle (1998). M. megalophylla differs from M. blainvillei in its significantly larger size (Silva Taboada, 1974; Rezsutek and Cameron, 1993). The morphology of the proximal humerus is very similar in these taxa, but distally the species differ in the development of the trochlea with respect to its posterior extension over the anterior surface of the spinous process. In M. megalophylla this surface is relatively well developed, reaching the base of the spinous process at its most posterior extent. In contrast, M. blainvillei has the trochlea clearly less developed and ending at a more anterior plane (a/a′ in fig. 10). As can also be seen in figure 10, the development and shape of the spinous process (b/b′) and of the posterolateral crest (c/c′) are distinct in these two species. The Mormoops samples from the Quaternary of Chapada Diamantina resemble M. megalophylla but have a slightly larger posterolateral crest (a structure on the posterior surface of the distal epiphysis extending over the shaft, laterally following the posterior ulna-trochlear facet) than that seen in our comparative sample of extant Mormoops. However, the significance of this trait, as well as the slight size differences observed, remain unclear. Accordingly, we treat the fossils of Mormoops from Chapada Diamantina as M. cf. megalophylla.

Pteronotus specimens are relatively abundant in the Chapada Diamantina collections, with 18 humeral fragments representing two species, P. parnellii and P. gymnonotus. Of the seven specimens representing P. gymnonotus, two are very well preserved, with one nearly intact and the other only slightly damaged proximally. Similarly, of the 11 humeri of P. parnellii in the collection, three are complete and three others have the shaft with both ends preserved but with some damage to various surfaces and processes. The morphology of the humerus in Pteronotus is quite different from that seen in Mormoops. The humerus of Pteronotus seemingly retains more of the basal noctilionoid morphology, mostly notably in the distal end. The main diagnostic features that distinguish the genus Pteronotus from other noctilionoids include the prominent anterior position of the humeral head relative to the greater tuberosity (the latter structure being more posteriorly positioned in Pteronotus than in other noctilionoids), and the marked posterolateral displacement of the spinal process, which is partially dissociated from the medial process.

Within Pteronotus a number of features of both the proximal and distal ends of the humerus allow unequivocal species identifications, with the distal end more drastically modified. Differences among species include variation in shape, angle, and degree of development of the lesser tuberosity at the proximal end, and at the distal end variation in trochlear shape, position, size, and in the relationship between the trochlea and the spinous process. The humeri of P. parnellii and P. gymnonotus stand clearly as the two largest in the genus, with P. parnellii the larger. Similar size distinctions are also observed among the fossils, although they are overall somewhat smaller than the extant specimens examined (a topic to be addressed further in future contributions). The morphology of the proximal end of the humerus of P. parnellii differs from that of P. gymnonotus in a number of details. The most conspicuous difference involves the development of the midbasal portion of the anterior surface of the greater tuberosity, which is wider in P. gymnonotus, extending over the anterior extremity of the supraglenoid fossa (a somewhat similar condition is also observed in P. macleayii and P. quadridens, and to a certain extent also in P. personatus and P. davyi). In contrast, in P. parnellii the basal portion of the greater tuberosity is relatively narrow and the anterior extremity of the supraglenoid fossa is more open, a condition shared by other noctilionoids. The most obvious distinction between the distal ends of the humeri of Pteronotus parnellii and P. gymnonotus concerns the position and angle of development of the spinous process. Pteronotus parnellii exhibits a unique condition in which the spinous process is located near a midline between the anterior and posterior plane of the shaft and projects distally, whereas in P. gymnonotus the spinous process is placed much more posteriorly from that midline, projecting more posteriorly and with its tip extending over the limits of the posterior surface of the shaft (a/a′ in fig. 13). The latter condition is shared by all species of Pteronotus (including the extinct species †P. pristinus) except for P. parnellii. Pteronotus species are also distinguished by different shapes of the distal trochlea when seen in lateral view, with this flange in P. parnellii displaying a circular outline as opposed to a more rectangular outline in P. gymnonotus (b/b′ in fig. 13). The fossils of the two species from Chapada Diamantina have a distal humeral morphology that conforms well to the known patterns of P. parnellii and P. gymnonotus as described above.

Pteronotus gymnonotus was documented as an extant taxon from Chapada Diamantina (Sbragia, 2012), but fossils of this species have not been previously reported from the region (Cartelle and Abuhid, 1994; Czaplewski and Cartelle, 1998). This species is known from the fossil record of South America only from a single locality, Cueva Toromo, Venezuela (Rincón, 1999). Material identified as Pteronotus aff. gymnonotus by Cartelle and Abuhid (1994) was reexamined by Czaplewski and Cartelle (1998), who reidentified it as P. parnellii, a species not known from the extant fauna of the Chapada Diamantina.

FIGURE 9. Anterior, posterior, medial, and lateral views of a left humerus of Mormoops cf. megalophylla (MN 57402). Scale bar = 1mm.

FIGURE 10. Differences in distal humeral morphology between Mormoops megalophylla (left) and M. blainvillei (right) as seen in posterior view with lateral toward the left side of the figure; see text for discussion: (a/a′) development and posterior extension of the trochlea (trochlea more strongly developed and extending further posteriorly in M. megalophylla); (b/b′) differences in shape and size of the spinous process (more bulbous distally and with strongly developed crestlike form posteriorly in M. megalophylla); and (c/c′) degrees of the development and shape of the posterolateral crest (more strongly developed in M. megalophylla).

FIGURE 11. Anterior, posterior, lateral, and medial views of a right humerus of Pteronotus gymnonotus (MN 57413). Scale bar = 1mm.

FIGURE 12. Anterior, posterior, medial, and lateral views of a left humerus of Pteronotus parnellii (MN 57423). Scale bar = 1mm.

FIGURE 13. Differences in distal humerus morphology between Pteronotus parnellii (left) and P. gymnonotus (right) as seen in medial view with posterior toward the left of the figure; see text for discussion: (a/a′) differences in degree of development and orientation of the epitrochlea and spinous process (epitrochlea less developed and spinous process shorter and directed more distally in P. parnellii); and (b/b′) differences in the outline of the trochlea (more circular in medial view in P. parnellii).

Family Noctilionidae Gray, 1821

The evolutionary history of the bulldog bats (genus Noctilio) extends at least to the late Tertiary of South America. A series of upper and lower molars nearly indistinguishable from those of modern Noctilio were reported by Czaplewski (1997) and Czaplewski et al. (2003) from the Middle Miocene (11.8–12.5 mya) of La Venta, Colombia. Based on size and morphology, these authors identified the La Venta fossils as Noctilio albiventris. Another fragmentary Noctilio fossil from the Miocene—a lower m1 from Rio Acre, 30 km W of Iñapari, Department of Madre de Dios, Peru—dates to the Huayquerian South American Land Mammal Age (9.5 mya). Because this specimen does not appear to fit within the range of variation known for N. albiventris, Czaplewski (1996) named it as a new species, †N. lacrimaelunaris. Merino et al. (2007) described an upper incisor referable to Noctilio sp. from deposits dated approximately 0.4 mya (Middle Pleistocene) from Las Grutas, Necochea, Province of Buenos Aires, Argentina. This discovery extended the known range for the genus at least 6° S latitude from the present distribution. However, the highly incomplete nature of the specimen precluded identification to species level.

Fossils assigned to the larger species of Noctilio, N. leporinus, have been found in Late Pleistocene and Holocene cave deposits of Barbuda, Cuba, and Puerto Rico (Reynolds et al., 1953; Choate and Birney, 1968; Silva Taboada, 1979; Pregill et al., 1994). However, no such fossils have been previously reported from mainland sites despite the fact that the species today ranges from Sinaloa, Mexico, south through Central and South America as far as northern Argentina and Paraguay (Simmons, 2005; Gardner, 2008a). New remains of Noctilio recovered from Chapada Diamantina stand as the first confirmed Quaternary record of the species N. leporinus (fig. 14) for South America. The material consists of two well-preserved humeral fragments and a few craniodental remains (the latter to be described in a subsequent publication). Noctilio leporinus has been reported from the extant fauna of the Chapada Diamantina (Oliveira and Pessôa, 2005), although no voucher specimen is known.

The morphology of the humerus of Noctilio is quite distinctive from that seen in other noctilionoids. The shaft is nearly straight and both proximal and distal articular surfaces lie in line with the shaft (fig. 14). Proximally, the humerus has an elliptical head, a feature not observed in any other noctilionoid except Mormoops. Distally, the humerus exhibits a unique medially extended epitrochlea, with the spinous process placed at its extremity.

The most obvious difference in humeral morphology between Noctilio leporinus and N. albiventris concerns size, with the humerus of N. leporinus much larger and more robust than that of N. albiventris. The cross-sectional shape of the shaft near the distal epiphysis also varies between these taxa: in N. albiventris the shaft tends to be more cylindrical in cross section, as opposed to a more rectangular cross-sectional shape in N. leporinus (c/c′ in fig. 15). Proximally, N. albiventris has a humeral head with a constriction toward the anterior end (associated with a prominent laterally curved proximal edge), which contrasts with a more smoothly rounded condition observed in N. leporinus. Distally, among some specimens of N. albiventris, the proximal border of the radial fossa has a prominent curved form (apparently correlated with the shaft having a cylindrical cross section near the epiphysis). This contrasts with the condition of N. leporinus in which the proximal border of the radial fossa is not as well developed over the anterior surface of the shaft (b′ in fig. 15). The epitrochlea is proportionally somewhat more mediolaterally expanded in N. leporinus than in N. albiventris. Noctilio leporinus has a distinct medial process that projects slightly over the anterior border of the epitrochlea, whereas this process is not developed in N. albiventris (e/e′ in fig. 15). The spinous process in N. leporinus has a relatively conspicuous tip that is recurved laterally and somewhat posteriorly oriented, whereas in N. albiventris the spinous process is relatively poorly developed, not recurved, and is partially fused with the lateral end of the epitrochlea (f/f′ in fig. 15). In N. leporinus the anteroproximal rim of the lateral ridge of the capitulum is narrow and forms a pointed tip that is curved toward the posterior side, whereas in N. albiventris this process is more rounded (a/a′ in fig. 15). The Noctilio humerus fossils from Chapada Diamantina are clearly referable to N. leporinus based on both size and morphology.

The genus Noctilio is in need of review and patterns of morphological variation within species need to be reevaluated with larger sample sizes from more localities to better control for intraspecific variation. Phylogeographic studies of Lewis-Oritt et al. (2001) and Pavan et al. (2013) have suggested that N. albiventris as currently recognized is composed by more than one taxon (see below). However, there is no evidence that N. leporinus represents of more than one species despite its broad geographic distribution (Lewis-Oritt et al., 2001; Pavan et al., 2013).

FIGURE 14. Anterior, posterior, medial, and lateral views of a left humerus of Noctilio leporinus (MN 57400). Scale bar = 1mm.

FIGURE 15. Differences in distal humerus morphology between Noctilio leporinus (left) N. albiventris (right) and as seen in anterior view with lateral toward the left side of the figure; see text for discussion: (a/a′) shape of anteroproximal portion of the lateral ridge of the capitulum (narrower and forming a pointed tip in N. leporinus); (b/b′) development of the proximal border of the radial fossa (border poorly defined in N. leporinus); (c/c′) cross-sectional shape of the shaft near its distal end (more rectangular in N. leporinus); (d/d′) anteroposterior width of the epitrochlea (wider in N. leporinus); (e/e′) degree of development of the medial process (more distinct and projecting slightly over the anterior border of the epitrochlea in N. leporinus); (f/f′) development and position of the spinous process (better developed and with a laterally recurved tip in N. leporinus).

DISCUSSION AND CONCLUSIONS

The Caatinga biome, one of two biomes entirely contained within the country of Brazil, is situated between a narrow strip of the Atlantic Rainforest biome, the eastern extent of the Cerrado biome, and the easternmost extent of the Amazonian biome (Leal et al., 2003; Prado, 2003). Despite its key location, little is known about the fauna of the Caatinga in comparison with the more heavily studied biogeographic regions that surround it (Leal et al., 2003). The Caatinga is usually described as a semiarid biome with intermittent rains and periodic severe drought seasons, and it harbors a mosaic of xerophytic and semiarid-adapted vegetation (Prado, 2003; Ab’Sáber, 2007). However, what is usually called “Caatinga” is actually composed of a multitude of vegetation profiles, including open savannas, dry forests, and rocky outcrops (Prado, 2003). The Caatinga has been traditionally considered to be relatively low in endemism when compared to other Brazilian biomes, but recent studies have shown that it has more endemic species than previously suspected (Prado, 2003; Leal et al., 2005). Given the general lack of knowledge, the number of species inhabiting the Caatinga is potentially very high since most of the region has never been surveyed (Leal et al., 2005). For mammals alone, at least 143 species are known for the Caatinga region, with two endemic rodent species (Oliveira et al., 2003). Recently described endemic bat species (Gregorin and Ditchfield, 2005) testify that the actual mammal diversity of the Caatinga biome may be underestimated, especially in the case of bats. Knowing the true extent of the diversity of Caatinga mammals is of importance for understanding the biogeographic dynamics of the region, especially given its pivotal position and contact zones with three other biomes (Amazonia, Atlantic Rainforest, and Cerrado). Understanding the dynamics of contraction and expansion of the mesic regions of Amazonia and Atlantic Rainforest during the Pleistocene will require knowledge of both modern and past faunas of the region (Prado, 2003; Santos et al., 2007).

The bat fauna currently known from the Caatinga biome consists of 86 extant species of bats (Sá-Neto and Marinho-Filho, 2013). Of those, at least 22 are currently known for the Chapada Diamantina plateau, the number being perhaps as high as 24 (Oliveira and Pessôa, 2005; Sbragia, 2012). The Chapada Diamantina is not a homogeneous environment, instead consisting of a mosaic of different kinds of vegetation including dry and riparian forests, rocky outcrops, and enclaves of Cerrado vegetation (Rocha et al., 2005). Bat distributions are likely influenced by this heterogeneity, although studies suggest that most species of bats are widely distributed along different environments (Oliveira and Pessôa, 2005; Sá-Neto and Marinho-Filho, 2013). The Chapada Diamantina is also extremely rich in caves, a factor that may have a great influence on the occurrence of bats since roost availability may be a limiting factor in open environments (Aguirre, 2002). Gregorin and Mendes (1999) found 11 species of bats in a single cave of the Chapada Diamantina, about half of the diversity known for the entire region.

One of the challenges of documenting the diversity of fossil bats for comparison to living communities is the incomplete nature of available specimens. The current study documents the value of humeral morphology for faunal and taxonomic analyses of bat paleofaunas, particularly those preserved in caves. Fossil bat assemblages in caves often consist largely of limb bones, with the humerus typically well represented (Czaplewski and Cartelle, 1998; Czaplewski et al., 2005; Grady and Olson, 2006). Humeral remains are frequently well preserved, probably because this bone in bats is robust and highly mineralized in comparison with other wing elements (Swartz et al., 2012). Although humeri have been used to identify bat species in many previous studies (e.g., Czaplewski et al., 2005; Grady and Olson, 2006), detailed descriptions of specific diagnostic features of the humerus are lacking for most extant taxa. Recently Czaplewski and Morgan (2012) described 20 morphological characters of the humerus potentially useful for phylogenetic studies of noctilionoids, and we plan to build upon these in future projects. Ongoing studies comparing humeri from species across all bat families confirm a high degree of species-specific morphological variation in this wing element (Salles et al., in prep.).

With the additional records reported here, the Quaternary bat fauna of Chapada Diamantina is the second most diverse locality known from the Quaternary of Brazil, with 29 bat species representing eight families and 24 genera. The Quaternary bat fauna of Chapada Diamantina includes the extinct giant vampire †Desmodus draculae as well as the genus Mormoops, which is not known from extant faunas in southern South America. Another 11 records (table 2) are not known from the extant fauna of the Chapada Diamantina plateau, although extant representatives of these species have been recorded from other localities in the Caatinga or Atlantic forest (Gardner, 2008b; Sá-Neto and Marinho-Filho, 2013). Most of the latter species belong to the families Mormoopidae and Molossidae, known for being difficult to capture using standard collecting methods (e.g., ground-level mist nets; Voss and Emmons, 1996; Simmons and Voss, 1998). We expect that future surveys using other methods (e.g., harp traps, roost searching, canopy netting, echolocation call surveys) may find that these taxa are indeed present in the extant fauna of the Chapada Diamantina plateau.

Records from the fossil fauna of Chapada Diamantina are potentially noteworthy from the perspective of historical biogeography. The Mormoops cf. megalophylla records reported here and by Czaplewski and Cartelle (1998) represent a significant range extension for the genus, whose current distribution extends only as far south as Colombia and Venezuela (Simmons, 2005). Extant populations from northern South America are recognized as a distinct subspecies, M. megalophylla tumidiceps, which is thought to be the sister group to Central/North American lineages (Dávalos, 2006). The Caribbean species, M. blainvillei, is in turn the sister group to this clade (Dávalos, 2006). It is not yet clear where the Chapada Diamantina Mormoops fits relative to these taxa, but it could be informative about the origins and diversification of the M. megalophylla lineage. In addition to biogeography, the record of Mormoops from Chapada Diamantina is also noteworthy because, based on the only age reference currently available for this fossil assemblage, it could be more than 10,000 years younger than the previous record (Czaplewski and Cartelle, 1998), suggesting that the genus remained a part of the Brazilian bat fauna until relatively recently. Future extractions of collagen from bone samples may shed light on the accurate age of the fossil bats from Chapada Diamantina. Regardless of whether the Chapada Diamantina Mormoops represents M. megalophylla or a similar undescribed species, inclusion of this taxon in future phylogenies and biogeographic analyses may shed light on the evolutionary history of the genus and correlations of mormoopid evolution with paleoenvironmental fluctuations during the late Pleistocene–Holocene.

Our understanding of the evolutionary history of the genus Noctilio is also enhanced by the Chapada Diamantina fossils. Fossils have previously provided a tantalizing yet highly limited view of early noctilionid evolution. The existence of bats apparently morphologically indistinguishable from modern N. albiventris in the Miocene might be interpreted as indicative of relative stasis in evolution of this group over a long period (~12 mya). In principle at least, this morphospace—for a medium-sized Noctilio (20–45 g)—has been around for more than 10 million years. However, the La Venta Miocene fossils consist of only a few isolated teeth (Czaplewski, 1997). In this context it is noteworthy that recent molecular phylogenetic studies have questioned the monophyly of extant bats referred to N. albiventris, suggesting that albiventris as currently recognized may represent a complex of at least three species that together are paraphyletic with respect to N. leporinus (Lewis-Oritt et al., 2001; Pavan et al., 2013). Pavan et al. (2013) found that living lineages of Noctilio albiventris originated quite recently, between 1.2–3.4 mya. The later finding is consistent with the idea that the La Venta fossils referred to N. albiventris probably represent a morphologically similar yet distinct species, and should not be assumed to indicate that N. albiventris is some sort of living fossil.

Based on a phylogenetic analysis including both mitochondrial and nuclear genes, Lewis-Oritt et al. (2001) hypothesized that N. leporinus quite recently diverged from within the N. albiventris complex, roughly 0.28–0.7 mya. Recently, Pavan et al. (2013) conducted a new phylogeographic analysis for the genus and proposed that N. leporinus differentiated a bit earlier than suggested by Lewis-Oritt et al. (2001), with date estimates ranging between 0.8–1.3 mya. Pavan et al. (2013) found support for a sister-group relationship between an Amazonian clade of N. albiventris and N. leporinus. However, phylogeographic analyses within the latter taxon suggest that N. leporinus arose in the Caribbean region and only later colonized South America. Three extant subspecies of N. leporinus have traditionally been recognized: N. l. mastivus (Caribbean islands and México south to northern Ecuador, Colombia, and Venezuela), N. l. leporinus (Guianas and the Amazon lowlands of Colombia, Ecuador, Peru, and northeastern Brazil), and N. l. rufescens (eastern Bolivia, Paraguay, northern Argentina, and southeastern Brazil) (Hood and Jones, 1984; Simmons, 2005). Pavan et al. (2013) found only partial correlation between their genetic results and these taxa as defined above, with N. l. mastivus from the Caribbean and México appearing as a paraphyletic assemblage relative to a South American clade of N. leporinus. No clear support for N. l. rufescens as a distinct lineage was found. Coalescent analyses suggested that the South American clade originated only 176,000 years BP and underwent rapid demographic expansion. The discovery of fossils of N. leporinus at Chapada Diamantina indicates that this species was already present in eastern Brazil by the late Quaternary, consistent with the idea of a rapid, successful expansion of N. leporinus across the continent.

Acknowledgments

This work could not have been completed without the loans received from the following institutions, as abbreviated in appendix 1: AMNH, UFRRJ, and MZUSP, for which we thank Eileen Westwig, Adriano Peracchi, and Mário de Vivo. We are also deeply indebted to a number of individuals who helped make possible the collection of fossils from the cave system studied: the people from the local community of Palmeiras; cave divers, coordinated by Robson Fonseca; speleologists, coordinated by Emílio Calvo; experts in vertical caving techniques, coordinated by Frederico Rabello; technicians of the UFRJ, coordinated by Jonas Moro, Milton Brasil, Marcos Romero Xavier, and Álvaro Carvalho; preparators Carlos Augusto Caetano and Carlos Rodrigues de Moraes Neto, who has also substantially contributed on the building of the MN bat collection of skeletons. We also thank the following individuals for their help and input: Livia Leon Paniagua, Luís Flamarion Barbosa de Oliveira, João Alves de Oliveira, Leila Maria Pessôa, and Peter Mann Toledo; and Jair da Silva for helping to document expeditions and also for the development of some illustrations here presented. Finally, we would like to make a special acknowledgment first to Káyo Ritter da Costa (MN student) for contributions in all stages of this work, and to Janir Barreto, the owner of the farm where the cave system entrance is located, who kindly helped us in innumerable ways with the expeditions and who helped make our stay there the most pleasant possible. This project was financed by a series of grants including three CNPq projects (483398/2009-8, 565046/2010-1, and 490710/2010-7), CONACYT (B330.313.), and NSF (DEB 0949859) to NBS. Logistic and auxiliary support was received from UFRJ, Agroinvest and Terra Brasilis.

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APPENDIX 1

Extant Specimens Examined

Specimens of extant bats used for taxonomic comparisons are listed below. Institutional acronyms are as follows: ALP, Adriano Lúcio Peracchi Collection, Universidade Federal Rural do Rio de Janeiro (UFRRJ) (Rio de Janeiro); AMNH, American Museum of Natural History (New York); MN, Museu Nacional, Universidade Federal do Rio de Janeiro (Rio de Janeiro); and MZUSP, Museu de Zoologia da Universidade de São Paulo (São Paulo).

FAMILY EMBALLONURIDAE

Peropteryx macrotis: AMNH 91237.

Taphozous georgianus: AMNH 197177.

Taphozous melanopogon: AMNH 235571.

FAMILY PHYLLOSTOMIDAE

Chrotopterus auritus: MN 46484; MN 56248.

Phyllostomus hastatus: AMNH 99607; AMNH 209334; AMNH 230171; AMNH 267901;

ALP 2287; MN 5167; MN 25708; MN 37330; MN 47235; MN 47236; MN 56238.

Tonatia bidens: MN 43083; MZUSP 22569.

Trachops cirrhosus: AMNH 267932; MN 50063.

Vampyrum spectrum: MN 46499.

FAMILY MORMOOPIDAE

Mormoops blainvillei: AMNH 238144.

Mormoops megalophylla: AMNH 25602.

Pteronotus davyi: AMNH 203565.

Pteronotus gymnonotus: ALP 9039.

Pteronotus macleayii: AMNH 60917.

Pteronotus parnellii: AMNH 254607; MN 36636; MN 37108; MN 37110; MN 37112.

Pteronotus personatus: AMNH 178468; ALP 9091.

Pteronotus quadridens: AMNH 39405.

FAMILY NOCTILIONIDAE

Noctilio albiventris: AMNH 210594; MN 60520; ALP 2880.

Noctilio leporinus: AMNH 256528; MN 47200; MN 47201; MN 47204.

FAMILY FURIPTERIDAE

Amorphochilus schnablii: AMNH 28601.

Furipterus horrens: MN 36057.

FAMILY THYROPTERIDAE

Thyroptera tricolor: AMNH 266361; MN 46443.

FAMILY NATALIDAE

Natalus stramineus: MN 43104; MN 59843.

FAMILY VESPERTILIONIDAE

Antrozous pallidus: AMNH 207615; AMNH 274878.

Bauerus dubiaquercus: AMNH 256832.

Histiotus montanus: AMNH 205649.

Histiotus velatus: MN 3373; MN 46450.

Myotis albescens: AMNH 234361.

APPENDIX 2

Fossil Specimens Examined

Specimens of fossil humeri examined in this study are listed below, with details about state of preservation abbreviated as follows: ch, complete humerus; ps, proximal humerus with part of the shaft preserved; p, proximal fragment only; ds, distal humerus with part of the shaft preserved; and d, distal fragment only. All specimens are deposited in the Museu Nacional, Universidade Federal do Rio de Janeiro (Rio de Janeiro), abbreviated as MN.

FAMILY PHYLLOSTOMIDAE

Chrotopterus auritus: MN 57430 (ch).

FAMILY MORMOOPIDAE

Mormoops cf. megalophylla: MN 57402 (ch); MN 57403 (ch); MN 57404 (ps); MN 57405

(ps); MN 57406 (ch); MN 57407 (ch); MN 57408 (ds); MN 57409 (ds); MN 57410 (ps).

Pteronotus gymnonotus: MN 57411 (ch); MN 57412 (ds); MN 57413 (ch); MN 57414

(ds); MN 57415 (ds); MN 57416 (ps); MN 57417 (p).

Pteronotus parnellii: MN 57418 (ds); MN 57419 (d); MN 57420 (ch); MN 57421 (ch);

MN 57422 (ch); MN 57423 (ch); MN 57424 (ch); MN 57425 (d); MN 57426 (ps); MN

57427 (ds); MN 57428 (ch).

FAMILY NOCTILIONIDAE

Noctilio leporinus: MN 57400 (ch); MN 57401 (ch).

FAMILY FURIPTERIDAE

Furipterus horrens: MN 57429 (d).

[1]Mastozoologia, Departamento de Vertebrados, Museu Nacional/UFRJ, Quinta da Boa Vista, s/n, Rio de Janeiro 20940-040, Brazil.

[2]Division of Vertebrate Zoology (Mammalogy), American Museum of Natural History.

[3]Laboratorio de Arqueozoología, Instituto Nacional de Antropología e Historia, Moneda # 16, Col. Centro México, D.F., México.

[4]Mastozoologia, Departamento de Vertebrados, Museu Nacional/UFRJ, Quinta da Boa Vista, s/n, Rio de Janeiro 20940-040, Brazil.

[5]Mastozoologia, Departamento de Vertebrados, Museu Nacional/UFRJ, Quinta da Boa Vista, s/n, Rio de Janeiro 20940-040, Brazil.

[6]Departamento de Zoologia, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, Belo Horizonte 31270-901, Brazil.

[7]Division of Vertebrate Zoology (Mammalogy), American Museum of Natural History.

[8]Division of Vertebrate Zoology (Mammalogy), American Museum of Natural History.