ANARTIA

Publicación del Museo de Biología de la Universidad del Zulia ISSN 1315-642X (impresa) / ISSN 2665-0347 (digital)

Anartia, 30 (junio 2020): 7-24

A new species of Rhipidomys

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Description of a new species of arboreal rat of the Rhipidomys fulviventer group, from Venezuela (Rodentia: Cricetidae)

Descripción de una nueva especie de rata arborícola del grupo

Rhipidomys fulviventer, de Venezuela (Rodentia: Cricetidae)

Franger J. García1*, Talita G. Almeida2, Marjorie Machado1, Mariana Isabel Delgado-Jaramillo3, Dayana Araujo-Reyes1, Oriana Vásquez-Parra1 & Guillermo Flórez4

1Departamento de Biología, Facultad Experimental de Ciencia y Tecnología, Universidad de Carabobo, Campus Bárbula, Naguanagua, Carabobo, Venezuela.

2Pos-graduação em Zoologia, Universidade Federal de Minas Gerais, Av. Antonio Carlos. 6627, 31270-010, Belo Horizonte, Brasil. 3Laboratório de Ciência Aplicada à Conservação da Biodiversidade, Departamento de Zoologia, Universidade Federal de Pernambuco, Rua Nelson Chaves s/n, Cidade Universitária–Recife PE 50670–420, Brasil.

4Pos-graduação em Evolução e Diversidade, Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, SP 09210-580, Brasil.

*Correspondence: cormura@yahoo.com

(Recibido: 13-09-2019 / Aceptado: 29-02-2020 / On line: 31-07-2020)

ABSTRACT

Arboreal rats of the genus Rhipidomys, belong to a taxonomic group of Neotropical distribution, included in the tribe Thomasomyini. In Venezuela, the Rhipidomys fulviventer group contains four taxa (R. fulviventer, R. tenuicauda, R. venus- tus, and R. wetzeli), only found in high elevation cloud forests and lowland rainforests. Because collections to date do not represent a thorough sampling of their geographic range, taxonomic arrangement of some taxa (e. g., Rhipidomys venustus), has been controversial. However, new specimens collected in recent years provide novel insights into the biogeographic variation of the genus Rhipidomys. In this article, we evaluate the taxonomy and geographic distribution of R. venustus based on a morphometric and morphological review that included integument, skull, teeth and post-cranial skeleton. Specimens examined cover the entire geographic range of this species. The results showed significant differences between populations, and supports the recognition of a new species inhabiting cloud forests in the Cordillera de la Costa Central and the Sistemas de colinas Lara-Falcón, Venezuela. The new species is larger than any of its congeners in the R. fulviventer group in this country. It shows dorsal and ventral coloration differences and unique qualitative characters associated with integument, skull and post-cranial skeleton. The geographic distribution of R. venustus is updated, and restricted to the Cordillera de Mérida. Remarks on the ecology and conservation status of the new taxon are also presented.

Key words: Andes, climbing rats, Rhipidomys venustus, Serranía del Litoral, Sierra de Aroa, Venezuela.

RESUMEN

Las ratas arborícolas del género Rhipidomys, pertenecen a un grupo taxonómico de distribución Neotropical, incluidas en la Tribu Thomasomyini. En Venezuela, el grupo Rhipidomys fulviventer está conformado por cuatro especies (R. fulviven- ter, R. tenuicauda, R. venustus y R. wetzeli), las cuales se encuentran en áreas boscosas, tanto en selvas nubladas de altura como en bosques lluviosos de tierras bajas. Debido a que hasta la fecha las colecciones de estos roedores no representan la totalidad de sus distribuciones geográficas, la ubicación taxonómica de algunas especies (e. g., Rhipidomys venustus), ha sido

F. J. García, T. G. Almeida, M. Machado, M. I. Delgado-J., D. Araujo-R., O. Vásquez-P. & G. Flórez

controversial. Sin embargo, muestras biológicas obtenidas en años recientes ofrecen una nueva percepción de la variación biogeográfica del género Rhipidomys. En este trabajo evaluamos la taxonomía y la distribución geográfica de R. venustus basados en una revisión morfométrica y morfológica que incluye integumento, cráneo, dientes y esqueleto post-craneal. Los ejemplares examinados cubren la totalidad de la distribución geográfica de esta especie. Los resultados mostraron dife- rencias significativas entre las distintas poblaciones y apoyan el reconocimiento de una nueva especie que habita los bosques nublados de la Cordillera de la Costa Central y del Sistema de colinas Lara-Falcón, en Venezuela. Esta nueva especie es la de mayor talla dentro de las otras que conforman el grupo Rhipidomys fulviventer en este país. Posee diferencias de colo- ración dorsal y ventral y caracteres cualitativos únicos asociados con el integumento, el cráneo y el esqueleto post-craneal. Finalmente, actualizamos la distribución geográfica de R. venustus, la cual se restringe a la Cordillera de Mérida. Se enfatiza además sobre la ecología y el estado de conservación del nuevo taxón.

Palabras clave: Andes, ratas arborícolas, Rhipidomys venustus, Serranía del Litoral, Sierra de Aroa, Venezuela.

INTRODUCTION

Arboreal rats of the genus Rhipidomys Tschudi, 1895, belong to a taxonomic group of Neotropical distribution, included in the tribe Thomasomyini Steadman & Ray, 1982 (Musser & Carleton 2005). Their geographic distri- bution extends from Panama to Southeastern Brazil and Northern Argentina, with records from some islands in the Caribbean Sea: Bonaire (Netherlands Antilles), Mar- garita (Venezuela) and Trinidad and Tobago (Tribe 2015).

The genus contains 23 species in South America, of which nine are reported for Venezuela (Tribe 2015). Of all the species occurring in the country, only two are endemic:

R. tenuicauda ( J. A. Allen, 1899) and R. venustus Thomas, 1900 (Tribe 2015). Rhipidomys tenuicauda was described from “Los Palmales” in the Macizo de Turimiquire, Sucre State, and it was considered as a subspecies of R. fulviven- ter Tate, 1939 (Tribe 1996). Rhipidomys venustus was de- scribed from “Las Vegas del Chama”, in the Cordillera de Mérida, and its geographic distribution was restricted to that area, however, it has since been found in cloud forests of the Cordillera de la Costa Central and in the Sistemas de colinas Lara-Falcón (Handley 1976, Linares 1998, Rivas

& Salcedo 2006, Anderson et al. 2012, García et al. 2013).

Because specimens of R. venustus are very scarce through- out its distributional range and there is no molecular evi- dence to support any phylogenetic arrangement of this spe- cies within the genus Rhipidomys (Costa et al. 2011, de la Sancha et al. 2011, Tribe 2015), it has been considered as a synonym of R. latimanus Tomes, 1860, or as a subspecies of that taxon (R. l. venezuelae Thomas 1900), and also of

R. fulviventer (R. f. venustus) (Eisenberg 1989, Tribe 1996).

Recently, using geometric morphometrics on skulls of Venezuelan specimens assigned to the Rhipidomys fulvi- venter group, García & Sánchez-González (2013), sug- gested a more detailed taxonomic study in populations of R. venustus from the Sierra de Aroa, since they could represent a different species from its Andean counterpart.

Based on an expanded analysis that included integu- ment, skull, post-cranial skeleton and morphometry on a greater number of specimens collected in recent years by different researchers in the Sierra de Aroa (Cordillera de la Costa Central, Venezuela), together with new records from the Cordillera de Mérida (Andes), Serranía del Lito- ral (Cordillera de la Costa Central) and Sierra de San Luis (Sistemas de colinas Lara-Falcón), housed in Venezuelan museums, we did a more exhaustively review of the taxo- nomic and geographic status of R. venustus, which resulted in the recognition of a new species inhabiting cloud forests from the Cordillera de la Costa Central and the Sistemas de colinas Lara-Falcón.

MATERIALS AND METHODS

Our description and comparisons between the new species and specimens from others species used in this work came from biological material stored in Venezuelan museums, generated as a result of several authors and labo- ratory projects (e.g. Handley 1976). Therefore, we declare that there was not manipulation of live animals in any of the different stages of the work.

We examine 84 specimens considered adults (age class- es 2-4; Appendix), following the criteria of Tribe (1996) and Costa et al. (2011). Specimens cover the geographic range of four species with three subspecies of the Rhipido- mys fulviventer group reported for Venezuela (Fig. 1): R. fulviventer elatturus Osgood, 1914 (n=7), R. f. javiersan- chezi García et al., 2015 (n=6), R. f. bisbali García et al., 2015 (n=2), R. tenuicauda (n=13), R. venustus (n=43) and R. wetzeli Gardner, 1989 (n=13). Additionally, we reviewed morphological descriptions available in the literature (Tribe 1996, 2015, Pacheco & Peralta 2011) for four species of the R. fulviventer group not present in Venezuela: R. f. fulviventer, R. ochrogaster J. A. Allen, 1901, R. similis J. A. Allen, 1912, and R. caucensis J. A. Allen, 1913.

A new species of Rhipidomys

Figure 1. Map of Venezuela showing the geographic distribution of the species of the Rhipidomys fulviventer group. Numbers corre- spond with examined and reported localities (Appendix).

Morphological analyses

For each specimen available of Rhipidomys venustus, we investigated variations in their integument (dorsal and ventral pelage coloration; dorsal and ventral pelage of ma- nus, hind feet and ears; vibrissae; scales, caudal coloration and mammae), skull and teeth. Additionally, we compared theses qualitative aspects with other taxa of the R. fulvi- venter group from Venezuela, Peru and Colombia.

Statistical analyses

We used descriptive and multivariate statistics both to document differences in means, ranges, intra-specific vari- ations, as well as integrating multiple variables between species recorded in the Venezuelan territory. However, our bivariate statistical analysis was restricted to compar- ing the populations previously named as R. venustus from the Andes with populations inhabiting the Cordillera de la Costa Central and the Sistemas de Colinas Lara-Falcón. Since species in the genus Rhipidomys do not show sexual dimorphism (Tribe 1996, Costa et al. 2011), males and fe- males were pooled in all analyses.

We conducted a Ryan-Joiner test on the relevant re- siduals to test for any departure from normality in our quantitative data. Additionally, we used the Levene’s test

for homogeneity of variances. To avoid an increase in the proportion of false positives (Type I error), we determined significance within families of tests (e. g., within a series of t-tests, each comparing the mean between two samples for one of several variables), using Holm’s (1979) modifi- cation of the Bonferroni procedure. For cranial measure- ments, we did a transformation for natural logarithms and used a two-sample t-test to compare, separately the means (external or cranial measurements) of R. venustus from the Andes with the corresponding mean of its most similar congener (Rhipidomys sp., from the Cordillera de la Costa Central and the Sistemas de Colinas Lara-Falcón). For ex- ternal measurements, we conducted a non-parametric test (Mann-Whitney U-test), due to non-normality and non- homogeneity of variance.

Additionally, we applied a Discriminant Function Analysis (DFA), with only 18 log-transformed cranial measurements ( Jolicoeur 1963), to compare mean cra- nial measurements and to discriminate between the sev- eral groups of Rhipidomys previously known. All statistical analyses were performed using SPSS, version 8.0.

We obtained the following external and cranial mea- surements used by Tribe (1996) for each specimen avail- able: Head and Body Length (HBL), Tail Length (TL),

F. J. García, T. G. Almeida, M. Machado, M. I. Delgado-J., D. Araujo-R., O. Vásquez-P. & G. Flórez

Hind-Foot Length (HFL), Ear Length (EL), Nasals Length (NL), Rostral Length (RL), Rostral Breadth (RB), Interorbital Breadth (IOB), Zygomatic Breadth (ZB), Braincase Breadth (BCB), Occipito-Nasal Length (ONL), Condylo-Incisive Length (CIL), Post-Palatal Length (PPL), Palatal Length (PL), Diastema Length (DL), Palatal Bridge Length (PBL), Incisive Foramina Length (IFL), Incisive Foramina Breadth (IFB), First Upper Molar Breadth (M1B), Palatal Breadth at M1 (PB1), Palatal Breadth at M3 (PB3), Mesopterygoid Fossa Breadth (MFB),Temporal Fossa Length (TFL), Zygo- matic Plate Length (ZPL), Rostral Height (RH), Upper Molar Row Alveolar Length (UMR), Greatest Length of Mandible (GLM), Mandibular Molar Row Alveolar Length (MMR) and Depth of Ramus (DR). The body mass (weight), was recorded in grams (g). External mea- surements and weight were obtained from museum speci- men tags. Cranial measurements were obtained with digi- tal calipers (accuracy = 0.02 mm). All measurements are reported in millimeters (mm).

Specimens examined are preserved in the following Venezuelan institutions (Appendix): Museo de la Estación Biológica de Rancho Grande (EBRG, Maracay), Museo de Historia Natural La Salle (MHNLS, Distrito Capital), Museo de Biología de la Universidad Central de Venezu- ela (MBUCV, Distrito Capital), Colección de Vertebra- dos de la Universidad de Los Andes (CVULA, Mérida) and Laboratorio Museo de Zoología de la Universidad de Carabobo (MZUC, Carabobo).

In our study, we follow the Biological Species Concept proposed by Mayr (1942), which postulates that “species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups”. In addition to the evidence of the geographi- cal isolation produced by the Lara depression, which sepa- rates populations defined as Rhipidomys sp., from the Cor- dillera Central and the Sistemas de Colinas Lara-Falcón of Rhipidomys venustus from the Andes, there is another geo- graphical barrier known as the Táchira depression, which separates R. venustus from the remaining Rhipidomys spe- cies of the Andes of South America. There is also clear evi- dence of phenotypic and morphometric differentiation, which are our basics for the description of the new species as new evolutionary linage (Baker & Bradley 2006).

RESULTS

Results indicate that the studied populations currently referred to R. venustus have intra-specific variations both in external features, as well as skull and post-cranial skel- eton. These differences were most notable for Andean

populations compared with the Cordillera de la Costa Central and the Sistemas de Colinas Lara-Falcón. In ad- dition, a set of external, cranial and post-cranial characters were found to be different from the Andean population (Rhipidomys venustus) with respect to the Cordillera de la Costa Central and the Sistemas de Colinas Lara-Falcón (Rhipidomys sp.).

Quantitative comparisons showed significant differ- ences between R. venustus with respect to Rhipidomys sp., in the following external measurements (P<0.005 for significant comparisons): HBL (P<0.01), TL (P< 0.005) and Weight (P< 0.005). In cranial measurements, the following variables were significant (after correction for multiple comparisons): ONL (P< 0.005), CIL (P< 0.005), PL (P< 0.02), DL (P< 0.005), TFL (P< 0.005), UMR (P< 0.005), RB (P< 0.005), RD (P< 0.005) and ZB (P< 0.005).

Multivariate analyses also supported differences be- tween Rhipidomys sp., R. venustus and the other five taxa of Rhipidomys evaluated. The first two axes, showed the separation between the seven groups in a multi-dimen- sional morphological space. The discrimination capacity was statistically significant (F=6.97; P< 0.0000), with a 100% of discriminant function correctly classified and accumulated total variance of 86.05% (Fig. 2). The RL, IFB, TFL, UMR and MMR were the principal variables responsible of the differentiation (P< 0.004), followed by DL, RB and GLM (P< 0.01).

These results allow us to propose a new name for the populations from the Cordillera de la Costa Central and the Sistemas de Colinas Lara-Falcón, which differ in mor- phometry, phenotype, cranial structure and post-cranial skeleton of its Andean counterparts.

Rhipidomys ochoagrateroli sp. nov.

http://zoobank.org/ urn:lsid:zoobank.org:act:F80E60A5-1682-48C8-83F1-E610882884CB

Rhipidomys venustus: Handley, 1976: 49 [in part].

Holotype: Male (MZUC-977, age class 2), preserved as skin, skull and post-cranial skeleton, collected by Frang- er J. García (field number: FG-2150) on November 13th 2011, at cloud forest, Yurubí National Park, Sierra de Aroa, Yaracuy State, Venezuela. Skin, skull (Figs. 3A; 4A, B, C), and post-cranial skeleton were in excellent condi- tion. Measurements of holotype are listed in Table 1.

Paratype: One female (MZUC-970, age class 2), pre- served in ethanol (70%), with skull extracted (Fig. 4C, D), collected by Franger J. García (field number: FG-1937), Douglas Mora and Luis Aular on April 21st 2011, at cloud forest, Yurubí National Park, Sierra de Aroa, Yaracuy State,

A new species of Rhipidomys

Figure 2. Discriminant function analysis (DFA), using 18 cranial measurements taken from adult specimens of the Rhipidomys fulvi- venter group in Venezuela.

Figure 3. Skins from five taxa of the Rhipidomys fulviventer group in Venezuela. A) Rhipidomys ochoagrateroli sp. nov., (MZUC–977), Rhipidomys venustus (EBRG–15253), Rhipidomys tenuicauda (EBRG–15259), Rhipidomys fulviventer javiersanchezi (EBRG–15250) and Rhipidomys fulviventer elatturus (EBRG–15243).

F. J. García, T. G. Almeida, M. Machado, M. I. Delgado-J., D. Araujo-R., O. Vásquez-P. & G. Flórez

Figure 4. Dorsal (A), ventral (B) and lateral (C) views of the skull and mandible of the holotype of Rhipidomys ochoagrateroli sp. nov., (MZUC–977). Scale = 5 mm.

Venezuela. Skull and body were in excellent conditions. Measurements of Paratype are listed in Table 1.

Type locality: La Trampa del Tigre (10°24’11’’N, 68°48’01’’W; 1940 m asl), sector El Silencio, Parque Na- cional Yurubí, Sierra de Aroa, Estado Yaracuy, Venezuela (Fig. 6A, B, C).

Distribution: Cordillera de la Costa Central (Sierra de Aroa and Serranía del Litoral) and in Sistemas de colinas Lara-Falcón (Sierra de San Luis, Juan Crisóstomo Falcón National Park), Venezuela.

Etimology: This species is dedicated to José Rafael Ochoa-Graterol, an outstanding taxonomist and ecolo- gist, whose contributions to the knowledge of the mam- mals of Venezuela has helped to document the great taxo- nomic diversity of this group in this country, particularly for marsupials, bats and rodents.

Diagnosis: Rhipidomys ochoagrateroli, sp. nov., is a large sized rodent distinguished from its congeners by the combination of the following characters: large body with a long and soft dorsal pelage; bright chestnut brown in color; long tail with small scales, imbricated and squar- ish in shape, dark brown triplet of small hairs covers two

Table 1. External and cranial dimensions of the type series of Rhipidomys ochoagrateroli sp. nov.

Measurements HBL

TL HFL EL NL RL RB IOB ZB BCB ONL CIL PPL PL DL PBL IFL IFB M1B PB1 PB3 MFB TFL ZPL RH UMR GLM MMR RD

Weight

scales in length; long terminal tuft of hairs present; large and robust skull with a long and wide rostrum; inflated nasolacrimal capsule; long and parallel incisive foramina; robust and broad hamular process of squamosal bone; and alisphenoid strut frequently bifurcated.

Description: Rhipidomys ochoagrateroli, sp. nov., is an arboreal rat of large size, compared with other species from the Rhipidomys fulviventer section in Venezuela (Table 2). The mistacial, superciliary and genal vibrissae are long (mistacials reaching the posterior edge of the ears). The in-

A new species of Rhipidomys

Figure 5. Dorsal and ventral views of four skulls of two species of Rhipidomys (age classes 2, respectively), showing the differences in size. Two females: A and B: R. venustus (EBRG-15258); C and D: R. ochoagrateroli sp. nov., (Paratype, MZUC-970). Two males: E and F: R. venustus (EBRG-15253); G and H: R. ochoagrateroli sp. nov., (Holotype, MZUC-977). Scale = 5 mm.

terramal and submental vibrissae are short and white. The ears are brown.

The manus are yellowish in specimens preserved both in ethanol as well as dry skins, and have very short brown hairs on the dorsal surface of the metacarpals. The meta- carpals and digits have silver hairs on their dorsal surface. The ungual tufts are white and extend to the tips of the claws or beyond. The claws are elongated. In dorsal view, the scales on the manus are granular in shape, small, and reach the second phalange from every digit. Five palmar pads are present: three inter-digitals, closely joined to each other; one large hypothenar and one thenar, robust and larger than the hypothenar. The ulnar-carpal vibrissae are short in size and white in color.

The dorsal pelage is long and soft, bright chestnut brown, not contrasting with the flanks and hairs are gray- based (the gray band covers more 50% of the hair length). The length of the mid-dorsal hairs is approximately 5-7 mm and the length of the guard hairs is 9-12 mm. The ven- tral pelage is white, but gray-based (the gray band covers at least 50% of hair length). The length of the mid-venter hairs is approximately 7-8 mm. Females have the following mammary formula: one post-axial pair; one abdominal pair, and one inguinal pair.

The hind feet are broad (frequently narrower compared with individuals of R. venustus of the same age class) and long, with a dark patch of short brown hairs on the dorsal surface of the metatarsals (except MZUC-980). The meta-

F. J. García, T. G. Almeida, M. Machado, M. I. Delgado-J., D. Araujo-R., O. Vásquez-P. & G. Flórez

Figure 6. A. Cloud forests in the Yurubí National Park, Yaracuy State, Northern Venezuela. B and C. Habitats (canopy and under- story) of R. ochoagrateroli sp. nov., in the cloud forest from the Trampa del Tigre (type locality).

tarsals and digits have silver hairs on their dorsal surface. The ungual tufts are white and extend to the tips of the claws or beyond. In dorsal view, the scales on the hind feet are granular in shape, small and reach the second phalange from each digit, and then they are arranged in a single scale, rectangular in shape. Six well developed plantar pads are present: four inter-digitals, closely joined to each oth- er; one small hypothenar with a broad base, and one large thenar with a reduced base.

The tail is much longer than the combined head and body length (Tables 1 and 2) and is uniformly-colored. The scales on the tail are small, imbricated and squarish in shape. Scales have a triplet of small dark brown hairs of equal size at the base (length approximated=3 mm; Fig. 7A, C); these hairs can reach two scales in length but are longer at the tip of the tail forming a long terminal tuft.

The skull is large size and robust. The rostrum is long and broad with nasals long, expanded anteriorly and in contact with the maxillary-frontal suture. The zygomatic arches, posterior root of the zygomatic arches, braincase and occipitals are broad. The lacrimal bones are elongated

and laterally expanded. The nasolacrimal capsule is inflat- ed and clearly visible in dorsal and ventral view. A gnathic process is present but poorly developed. The zygomatic spine on the anterior edge of the zygomatic plate is absent. The zygomatic notch is concave.

The interorbital region is convergent anteriorly. The supraorbital ridges are weakly developed. The ethmoid foramen is present. The hamular process of squamosal bone is robust, uniformly broad and clearly separating a distinct subsquamosal fenestra and postglenoid foramen (Fig. 8A); although in two specimens the postglenoid fo- ramen is almost precluded (paratype and MZUC-973), which is smaller than subsquamosal fenestra (Fig. 8A). A broad alisphenoid strut is frequently present (except EBRG-15251) and bifurcated (Fig. 8C), separating the masticatory–buccinator foramen of the alisphenoid canal; when not is bifurcated (MZUC-900, 971, 975, 979), the alisphenoid canal and masticatory-buccinator foramen are fused. The sphenofrontal foramen is small.

The incisive foramina are long, convergent anteriorly and parallels in the medial part. These foramina reach

Table 2. External and cranial dimensions of Rhipidomys ochoagrateroli sp. nov., and its congeners from the Rhipidomys fulviventer group from Venezuela. The des- criptive statistic included the sample size (n), mean and range (minimum and maximum).

Measurements Rhipidomys

Rhipidomys

Rhipidomys

Rhipidomys

Rhipidomys

ochoagrateroli sp. nov. venustus

EXTERNAL n=17 n=26

fulviventer bisbali fulviventer elatturus wetzeli

n=2 n=7 n=13

HBL 140.41

111.00-190.00

TL 164.88

137.00-190.00

HFL 27.41

23.00-31.00

EL 19.52

A new species of Rhipidomys

16.00-21.00

120.65

94.00-198.00

139.74

74.00-168.00

26.14

22.00-30.00

19.87

16.00-25.00

49.24

109.00

93.00-125.00

146.00

132.00-160.00

26.50

25.00-28.00

17.50

17.00-18.00

105.14

92.00-112.00

117.71

107.00-133.00

24.28

22.00-26.00

19.14

17.00-21.00

88.77

63.00-103.00

123.77

82.00-140.00

22.77

21.00-24.00

17.15

15.00-21.00

Weight 64.37

37.00-81.00

26.00-95.00 (n=24)

— 32.71

23.00-39.00

25.56

18.00-32.00

15

Cranials n=13 n=26

n=2 n= 6 n=4

NL 11.49

10.60-12.80

RL 10.00

8.80-10.90

RB 5.20

4.70-6.50

IOB 4.85

4.60-5.00

ZB 17.67

16.60-18.20

BCB 12.88

12.20-14.20

ONL 32.95

31.90-34.40

CIL 30.23

29.20-31.90

PPL 12.46

11.00-13.30

PL 15.16

14.70-16.30

11.05

9.60-12.50

9.86

8.70-11.50

4.38

3.70-5.70

4.74

4.20-5.10

16.50

14.60-18.20

12.94

12.00-14.10

31.69

29.30-38.40

28.70

25.60-31.90

11.95

10.10-13.40

14.51

12.40-16.30

10.30

9.70-10.90

9.80

9.70-9.90

5.50

5.10-5.90

4.65

4.60-4.70

15.95

15.40-16.50

13.15

13.10-13.20

30.25

29.10-31.40

26.85

25.70-28.00

10.20

9.60-10.80

13.85

13.20-14.50

10.23

9.80-10.60

8.45

8.10-8.90

4.73

4.30-5.20

4.30

4.10-4.50

15.13

14.50-15.60

12.03

11.70-12.30

28.48

28.10-29.40

25.83

25.30-26.90

10.58

10.40-10.90

12.83

12.60-13.10

8.87

8.30-9.10

7.47

7.00-7.80

4.52

4.40-4.70

4.12

4.00-4.20

13.30

13.20-13.40

11.40

11.10-11.80

25.00

24.50-25.50

22.17

21.70-23.20

9.02

8.70-9.60

10.97

10.60-11.40

F. J. García, T. G. Almeida, M. Machado, M. I. Delgado-J., D. Araujo-R., O. Vásquez-P. & G. Flórez

Table 2. (Continuation)

Measurements

och

DL PBL

IFL

5.70-6.70

IFB

M1B

16

PB1 PB3 MFB TFL ZPL RH UMR GLM MMR

DR

3.60-4.20 2.90-4.40 3.10-3.70 3.20-4.90 3.40-3.70 3.20-3.40 2.70-2.90

A new species of Rhipidomys

Figure 7. Medial sections of the tails of two species of Rhipidomys showing the differences related with density and size of hairs (A): Rhipidomys ochoagrateroli sp. nov., (Holotype, MZUC-977) and (B): Rhipidomys venustus (EBRG-28303). (C): individual hairs of Rhipidomys ochoagrateroli sp. nov., (left) and Rhipidomys venustus (right). Scale = 1 mm.

Figure 8. Morphology of the hamular process of the squamosal (hps) in Rhipidomys ochoagrateroli sp. nov., (A = Holotype, MZUC- 977) and Rhipidomys venustus (B = EBRG-15255). In addition, we report the variation in the alisphenoid strut (als); frequently bi- furcated in Rhipidomys ochoagrateroli sp. nov., (C = Holotype, MZUC-977) and not bifucarted in Rhipidomys venustus (D = EBRG- 1255). Scales = 5 mm.

F. J. García, T. G. Almeida, M. Machado, M. I. Delgado-J., D. Araujo-R., O. Vásquez-P. & G. Flórez

anterior roots of the first upper molars. The palate is long (compared with other species in the R. fulviventer section from Venezuela) and broad on M1 and M3. Two longitu- dinal grooves are present on the palate. The palatal foram- ina are small, usually present in three pars on each side. The lateral postpalatal foramina are present. The mesoptery- goid fossa is deep and with a small postpalatal projection. The sphenopalatine fissures are long and frequently are present (except in the paratype and MZUC-971, which lack these fissures). The parapterygoid fossae are frequent- ly fenestrated (except MZUC-970). The foramen ovale is large. The carotid circulatory pattern is of primitive type, with a stapedial foramen large; and the supraorbital ramus of the stapedial artery following groove across inner sur- face of alisphenoid to sphenofrontal foramen; Pattern 1 of Voss (1988).

The upper incisors are robust and opisthodont. The up- per molars are pentalophodont, large and robust. The first upper molars have protocone, hypocone, paracone and metacone developed. The anterolingual and anterolabial conules frequently are divided by an anteromedian flex- us (except MZUC-971, 973). The anteromedian style is present and well developed. The anteroflexus and antero- median flexus are separated. The protoflexus, mesoflexus, hypoflexus, paraflexus, metaflexus and posteroflexus are long. The anterior and median mures are present and are

developed. The medial and labial fossettes on the second upper molars are long and are separated.

The mandible is long, broad and high in the condylar region and coronoid processes. The sigmoid notch is shal- low. The first lower molars have metaconid, entoconid, protoconid and hypoconid. The anterolingual and labial conulids are not frequently divided by an anteromedian flexid (except MZUC-974). The anteroflexid, and proto- flexid are present. The mesoflexid, hypoflexid, entoflexid and posteroflexid are long. The second lower molars have metaconid, entoconid, protoconid and hypoconid. The mesoflexid, entoflexid, hypoflexid and protoflexid are present, and are long. The posteroflexid is bifurcated.

The scapula (Fig. 9A), is high and straight; the acromion is developed, rounded and elongated toward the scapular crest; the acromial angle is slightly curved (approximately 110°). The medial edge is slightly convex; the lateral edge is almost straight and the upper edge is slightly concave. The scapular notch is shallow. The upper angle is less curved than lower angle. The infraspinous fossa is larger than su- praspinous. The infraglenoid tubercle is developed.

The humerus (Fig. 9C), is large with the head developed and larger than greater tubercle. The deltoid process is devel- oped. The olecranon and coronoid fossa are very deep. The medial epicondyle is more developed than lateral epicondyle. The capitulum is large. The humeral trochlea is shallow.

Figure 9. Posterior views of the morphology of right scapula and right humerus of adult Rhipidomys ochoagrateroli sp. nov., (A, C; Holotype: MZUC-977) and Rhipidomys venustus (B, D; CVULA-I-6157), showing the differences in size. Scale = 5 mm.

A new species of Rhipidomys

Comparisons: Externally, R. ochoagrateroli sp. nov., can be easily distinguished from R. leucodactylus Tschudi, 1844, R. couesi J. A. Allen & Chapman, 1893, R. venezuel- ae Thomas, 1896 and R. nitela Thomas, 1901 (Rhipidomys leucodactylus group), because of its smaller size and from

R. macconnelli De Winton, 1900 (Rhipidomys macconnelli group), because of its comparatively large size. The ventral coloration is also different; the species in the R. leucodac- tylus and macconnelli groups have a venter pure white or cream (unicolored hairs), but R. ochoagrateroli sp. nov., although it has a venter white, the hairs are gray-based (bi- colored).

In cranial features, the carotid circulatory pattern is primitive in R. ochoagrateroli sp. nov. (Pattern 1, Voss 1988), against a derived pattern for species in the R. leu- codactylus and macconnelli groups (Patterns 2 and 3, Voss 1988).

Compared with the species of the R. fulviventer group from Venezuela, R. ochoagrateroli sp. nov., is larger than R. tenuicauda, R. f. javiersanchezi, R. f. bisbali, R. f. elatturus and R. wetzeli in most external and cranial measurements, as well as body mass and qualitative features (Table 2). In addition, R. ochoagrateroli sp. nov., has a skull and man- dible different in shape with respect to its congeners of the

R. fulviventer group from Venezuela (García & Sánchez- González 2013; named in that study as Rhipidomys venus- tus Aroa).

Regarding external and cranial features, R. ochoagrater- oli sp. nov., is different of R. tenuicauda in the following aspects: dorsal pelage coloration (bright chestnut brown vs. bright orange-brown agouti); ventral pelage coloration (white hair tips vs. cream hair tips); hind feet (long and broad vs. small and narrow); hair colors on the dorsal surface of the metatarsals (dark brown vs. pale brown); terminal tuft of tails length (15.38 mm [n=17] vs. 11.64 mm [n=13]); skull and palate (large and long vs. small and short); palatal foramina (3–4 pairs vs. 1–2 pairs); parapterygoid fossae (fenestrated vs. not fenestrated).

Rhipidomys ochoagrateroli sp. nov., is different of Rhipi- domys f. javiersanchezi in the following features: dorsal pel- age coloration (bright chestnut brown vs. brown agouti); ventral pelage coloration (white hair tips vs. cream hair tips); hind feet (broad vs. narrow); hair colors on the dor- sal surface of the metatarsals (dark brown vs. pale brown); terminal tuft of tails length (15.38 mm [n=17] vs. 8.50 mm [n=5]); skull and palate (large and long vs. medium and short); Parapterygoid fossae (fenestrated vs. not fenes- trated); accessory sphenofrontal foramen in the alisphe- noid (absent vs. present).

Rhipidomys ochoagrateroli sp. nov., differs of R. f. bisba- li, in the dorsal pelage coloration (bright chestnut brown

vs. brown agouti); hind feet (broad vs. narrow); hair colors on the dorsal surface of the metatarsals (dark brown vs. brown); terminal tuft of tails length (15.38 mm [n=17] vs. 6.04 mm [n=1]); skull and palate (large and long vs. small and short ); parapterygoid fossae (fenestrated vs. not fenestrated); alisphenoid strut (frequently bifurcated vs. not bifurcated).

Rhipidomys ochoagrateroli sp. nov., is different of Rhipi- domys f. elatturus in the dorsal pelage coloration (bright chestnut brown vs. pale brown); ventral pelage coloration (white hair tips vs. cream hair tips); hind feet (long and broad vs. short and narrow); hair colors on the dorsal sur- face of the metatarsals (dark brown vs. pale brown); skull and palate (large and long vs. small and short); sphenopal- atine fissures (long vs. short); parapterygoid fossae (fenes- trated vs. sometimes fenestrated).

Rhipidomys ochoagrateroli sp. nov., is different of Rhipi- domys wetzeli in the dorsal pelage coloration (bright chest- nut brown vs. bright orange agouti); ventral pelage color- ation (white hair tips vs. cream or orange hair tips); hind feet (long and broad vs. short and narrow); hair colors on the dorsal surface of the metatarsals (dark brown vs. pale brown); terminal tuft of tails length (15.38 mm [n=17] vs. 13.30 mm [n=4]); skull size (large vs. small); palatal foramina (small and 3-4 pairs vs. one pair large).

Rhipidomys ochoagrateroli sp. nov., is morphologically similar to R. venustus, but is larger both in external and cranial morphometry, as well as body mass (Table 2). The following measurements are statistically significant: HBL, TL, Weight, RB, ZB, ONL, CIL, PL, DL, TFL, DR and UMR.

The mistacial vibrissae are less abundant in R. ochoag- rateroli sp. nov., (R. venustus has densely abundant mista- cial vibrissae); the tail is less furry in R. ochoagrateroli sp. nov., with a triplet of short hairs dark brown on each scale covering approximately two scales in length (R. venustus has a very furry tail and a triplet of small hairs, frequently light brown, covering approximately six scales; Fig. 7); dorsal hairs in R. ochoagrateroli sp. nov., are shorter than

R. venustus; R. ochoagrateroli sp. nov., has a venter pure white, versus frequently yellowish (cream) in R. venustus;

R. ochoagrateroli sp. nov., has a larger skull than R. venus- tus (Fig. 5); the incisive foramina are parallel in R. ochoag- rateroli sp. nov., whereas is mostly laterally expanded in R. venustus); the nasolacrimal capsule is more inflated and developed in R. ochoagrateroli sp. nov., than in R. venustus; the hamular process of the squamosal bone is uniformly broad and robust in R. ochoagrateroli sp. nov., whereas is comparatively narrow in R. venustus (Fig. 8). Although in

R. ochoagrateroli sp. nov., the alisphenoid strut is variable (bifurcated or not), in all examined specimens of R. venus-

F. J. García, T. G. Almeida, M. Machado, M. I. Delgado-J., D. Araujo-R., O. Vásquez-P. & G. Flórez

tus the alisphenoid strut is not bifurcated; therefore, the alisphenoid canal and masticatory-buccinator foramen are fused (Fig. 8). The scapula and humerus are larger in R. ochoagrateroli sp. nov., than in R. venustus (Fig. 9).

Compared with other taxa belonging to the R. fulviven- ter group from Colombia and Peru (R. caucensis, R. similis,

R. f. fulviventer and R. ochrogaster), R. ochoagrateroli sp. nov., is larger than R. caucensis in the HBL (140.41 mm vs. 110.00 mm) and upper molar row (5.20 mm vs. 4.50 mm) (Tribe 2015). Additionally, R. caucensis has a de- rived carotid circulation pattern (Tribe 1996, 2015) and

R. ochoagrateroli sp. nov., has a primitive carotid circula- tion pattern. Rhipidomys similis has a dorsal pelage color- ation reddish to orange brown or yellowish rufous, lined with black and the ventral pelage is cream or orange (Tribe 1996, 2015); in R. ochoagrateroli sp. nov., the dorsum is chestnut brown, without a line black, and the venter is white; the supraorbital ridges are slightly developed in R. similis and in R. ochoagrateroli sp. nov., are weakly devel- oped or absent; the sphenopalatine fissures in R. similis are small to medium, opposite at large and long in R. ochoag- rateroli sp. nov.,; the upper molar row is larger in R. similis than in R. ochoagrateroli sp. nov., (5.25 mm vs. 5.02 mm) (Tribe 2015).

Rhipidomys f. fulviventer is medium-sized with a dor- sal pelage coloration tinged with olive (Tribe 1996, 2015) and not so bright chestnut brown as in R. ochoagrateroli sp. nov.,; ventral pelage usually has an orange suffusion (Tribe 2015) and in R. ochoagrateroli sp. nov., is white; flanks are paler than dorsum (flanks not are contrasting in

R. ochoagrateroli sp. nov.,) and it has small sphenopalatine fissures (long in R. ochoagrateroli sp. nov.,). Rhipidomys ochrogaster is larger than R. ochoagrateroli sp. nov., in the HBL (> 150.00 mm vs. 140.41 mm), tail (> 190.00 mm vs.

164.88 mm) and the upper molar row (> 6.00 mm vs. 4.50 mm) (Pacheco & Peralta 2011, Tribe 2015). Rhipidomys ochrogaster has a dorsal pelage bright orange-brown and a ventral pelage pale-orange (Tribe 1996, Pacheco & Peralta 2011); in R. ochoagrateroli sp. nov., the dorsal pelage is chestnut brown and the ventral pelage is white.

DISCUSSION

The recognition of Rhipidomys ochoagrateroli sp. nov., is based exclusively on a morphologic analysis and metric comparisons; methodology previously used in descrip- tions of other taxa of thomasomyines, as Thomasomys Coues, 1884, or Rhipidomys (Leo & Gardner 1993, Gard- ner & Romo 1993, Tribe 2005). Although the identifi- cation of this new species is clear and unambiguous, it is necessary to evaluate its phylogenetic history and position

in the future, including molecular data from all taxa of the genus Rhipidomys from Venezuela.

Rhipidomys ochoagrateroli sp. nov., inhabits high eleva- tions (1300-2223m asl) in the Cordillera de la Costa Cen- tral and in the Sistemas de Colinas Lara-Falcón. It has been recorded in four National Parks (Yurubí, Waraira Repano [El Ávila], Henri Pittier and Juan Crisóstomo Falcón) and in the Pico Codazzi Natural Monument (Handley 1976, Rivas & Salcedo 2006, Anderson et al. 2012, García et al. 2013, 2016). All records are from cloud forests with a low degree of disturbance, suggesting it may be vulner- able to habitat fragmentation. Throughout its geographic range, R. ochoagrateroli sp. nov., was captured on vines and branches in mature forests (Handley 1976, Rivas & Sal- cedo 2006, Anderson et al. 2012, García et al. 2013, 2016).

Rhipidomys ochoagrateroli sp. nov., is sympatric with the following species of small non-volant mammals: Cal- uromys trinitatis Thomas, 1894, Didelphis marsupialis L., 1758, Gracilianus marica Thomas, 1898, Marmosa demer- arae (Thomas, 1905), Marmosops carri J. A. Allen & Chap- man, 1897, M. fuscatus Thomas, 1896, M. ojastii García, Sánchez & Tenedo, 2014, Cryptotis aroensis Quiroga- Carmona & Molinari, 2012, C. venezuelensis Quiroga- Carmona, 2013, Notosciurus granatensis (Humboldt, 1811), Heteromys anomalus Thompson, 1815, H. catop- terius Anderson & Gutiérrez, 2009, Necromys urichi ( J. A. Allen & Chapman, 1867), Microryzomys minutus Tomes, 1860, Neacomys tenuipes Thomas, 1900, Nephelomys cara- colus (Thomas, 1914), Olygoryzomys delicates ( J. A. Allen

& Chapman, 1897), Oecomys bicolor (Tomes, 1860), O. flavicans Thomas, 1894, O. trinitatis ( J. A. Allen & Chap- man, 1893), and R. f. javiersanchezi (Handley 1976, Rivas

& Salcedo 2006, Anderson et al. 2012, García et al. 2013, 2014, 2015, 2016).

On the other hand, to date, Rhipidomys venustus has been documented to have a wide geographic distribution in the Cordillera de Mérida (Handley 1976, Tribe 1996). In that region, it is known almost exclusively in cloud for- ests at elevations above 1000 meters and in páramo eco- systems (Handley 1976, Díaz de Pascual 1988, Durant & Díaz de Pascual 1995, Tribe 1996, Soriano et al. 1999a, b, Ochoa et al. 2001).

Throughout its geographic distribution range, R. ve- nustus is sympatric with the following species of small non-volant mammals: Caluromys trinitatis Thomas, 1894, Didelphis marsupialis, D. pernigra Allen, 1900, Gracilia- nus dryas Thomas, 1898, Marmosops fuscatus, Marmosa de- merarae, Cryptotis meridensis Thomas, 1898, Notosciurus granatanesis, Heteromys anomalus, H. australis Thomas, 1901, Ichthyomys hydrobates (Winge, 1891), Neusticomys mussoi Ochoa & Soriano, 1991, Necromys urichi, Mela-

A new species of Rhipidomys

nomys colombianus (Allen, 1899), Microryzomys minutus, Neacomys tenuipes, Nectomys rattus Petter, 1979, Nephelo- mys meridensis (Thomas, 1894), Oecomys bicolor, O. flavi- cans, O. trinitatis, Oligoryzomys delicatus, Sigmodontomys alfari J. A. Allen, 1897, Sigmodon hirsutus Burmeister, 1854, Aepeomys lugens Thomas, 1896, A. reigi Ochoa, Aguilera, Pacheco & Soriano, 2001, Rhipidomys couesi,

R. venezuelae, Thomasomys emeritus Thomas, 1916 and

T. vestitus Thomas, 1898 (Handley 1976, Díaz de Pascual 1988, Soriano et al. 1999a, b, Durant & Díaz de Pascual 1995, Ochoa et al. 2001).

Our discovery of a new species has biogeographic im- plications for R. venustus, now restricted to the Andes (Cordillera de Mérida). Thus, it is necessary to increase ef- forts to conserve R. venustus, which is isolated of its sister species by the Táchira and Lara depressions, in an area that has suffered systematic fragmentation since pre-Columbi- an times (Soriano et al. 1999a, b).

Warm and dry climatic conditions, together with a belt of deciduous vegetation in the Táchira depression are postulated as important barriers that restrict the disper- sal in some forest mammalian taxa (Soriano et al. 1999b, Gutiérrez et al. 2015). However, some studies in Colom- bia, have recorded species of non-volant small mammals, known previously only from the Cordillera de Mérida in Venezuela (Neusticomys mussoi and Nephelomys meriden- sis) (Rodríguez-Posada 2014, Villamizar-Ramírez et al. 2017). Also in Venezuela, some authors have document- ed the presence of taxa with geographic distributions in the Colombian Cordillera Oriental (Heteromys australis Thomas, 1901 and Marmosa waterhousei Tomes, 1860) (Anderson & Soriano 1999, Gutiérrez et al. 2011), and others have shown that between these ranges, there is not morphological and molecular differentiation of two red brocket deer species, Mazama bricenii Thomas, 1908 and Mazama rufina (Pucheran, 1851) (Gutiérrez et al. 2015). This evidence indicates that the Táchira depression should not be assumed as an absolute barrier for species apparent- ly restricted to habitats of high elevations of the northern Andes (Gutiérrez et al. 2015).

ACKNOWLEDGEMENTS

The authors thank the following museum curators for allowing us access to specimens under their care: Ja- vier Sánchez-Hernández (EBRG); Johnny Murillo, Carla Aranguren and Pascual J. Soriano (CVULA); Mercedes Salazar and Carmen Ferreira (MBUCV); Olga L. Herrera and Hugo Rodríguez (MHNLS). We also thank Antonio Pérez Sarmiento and Jonathan Liria of the Departamento de Biología (FACyT; Universidad de Carabobo), for their

support during the course of this investigation. The pho- tograph in Fig. 3 is courtesy of Helga Terzenbach. Paula Emery, Marcelo Weksler, Pablo Teta and Carmen Ferreira provided valuable suggestions and corrections to improve earlier versions of the manuscript. Paula Emery, Beth E. Gerstner, Karl Berg, Fernando Riera and Ángel L. Viloria assisted us in the correction of the English language.

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A new species of Rhipidomys

APPENDIX

Gazetteer and specimens examined. Collection locali- ties for species of the Rhipidomys fulviventer group exami- ned. Numbers correspond with records shown in Fig. 1. Localities of specimens not examined in this study are re- ported with their reference.

Rhipidomys ochoagrateroli sp. nov.

1. La Trampa del Tigre (type locality: 10°24’N - 68°48’W; 1940 m asl), sector El Silencio, Parque Na- cional Yurubí, Sierra de Aroa, Estado Yaracuy (MZUC- 970-75; 978-81, 1539); 2. Monumento Natural Pico Codazzi, Sector La Florida (10°25’N - 67°18’W; 2000 m asl), carretera vía El Limón, Estado Aragua (MZUC- 900); 3. Monumento Natural Pico Codazzi (10°24’N

• 67°20’W; 1827 m asl), Estado Aragua (MZUC-901);

  1. Parque Nacional Henri Pittier, El refugio, Pico Guaca- maya (10°22’N - 67°40’W; 1720 m asl), Estado Aragua: includes: Parque Nacional Henri Pittier, La Cumbre, Estado Aragua (EBRG-28304, 28305, 28306, 28307);

  2. Parque Nacional El Ávila (10°33’N - 66°52’W; 2135 m asl), 9.4 km, Norte de Caracas, Distrito Federal (EBRG- 15251): includes: Distrito Capital, Pico Ávila, near Hotel Humboldt (Tribe, 2015); 6. San Luis, Parque Na- cional Juan Crisóstomo Falcón, sector Cumbre de Uría (11°13.581’N - 69°36.932’W; 1320 -1370 m asl), 9 km

  de Cabure (EBRG-24865).

  
  

  Rhipidomys venustus

  7. Hacienda Misisí (09°21’N - 70°18’W; 2210 m asl), 14 km E Trujillo, Estado Trujillo (EBRG-15253, 15254, 15255, 15256); 8. 5.5 km E and 2 km S Tabay (08°36’N

• 71°01’W; 1530-2077 m asl), Parque Nacional Sierra Nevada, Estado Mérida (EBRG-15258); 9. Monte Zerpa (8°38’N - 71°09’W; 2100 -2160 m asl), 3 km N de Mé-

  rida, Estado Mérida (CVULA-1114, 1231, 1930, 2779;

  EBRG-28300, 28301, 28302, 28303). 10. El Blanquito (09°40’N - 69°37’W; 1600 m asl), 9 Km SE de Sanare,

  Parque Nacional Yacambú, Estado Lara (CVULA-2737); 11. Cerro Alto (8°49’N - 70°32’W; 1460 m asl), 2 km NO de la Soledad, Parque Nacional Sierra Nevada, Estado Ba- rinas (CVULA-5937, 5938, 6135); 12. Laguna Brava, Pá- ramo de Mariño (8°39.20’N - 70°53.56’W; 2090 m asl), Parque Nacional Sierra Nevada, Estado Mérida (CVU- LA-3282); 13. Mirabel (8°41’N - 71°26’W; 1500 m asl),

  3 km SSE de la Azulita, Estado Mérida (CVULA-6073, 6074); 14. El Baho (8°50’N - 7 0°43’W; 3010 m asl), 5 km

  SO de Santo Domingo, Estado Mérida (CVULA-6145, 6157, 6158); 15. El Zumbador (7°58’N - 72°04’W; 2650

  m asl), 8 km SSO de El Cobre, Parque Nacional General

  Juan Pablo Peñaloza, Estado Táchira (CVULA-5740); 16. Río Chama (08°33’N - 71°13’W; 1400 -2020 m asl):

  includes: Cafetos de Chama; montañas de Chama; Las Vegas del Chama [type locality]), Estado Mérida (Tribe 1996); 17. Mérida (08°35’N - 71°07’W; 2600 m asl),

  3.1 km SE, 4.1 km SE de Mérida, Estado Mérida (Tribe, 1996); 18. Río Milla (08°38’N - 71°07’W; 1700 -3050 m

  asl): includes: Río Mucujún, ladera del Páramo San An- tonio, Estado Mérida (Tribe 1996); 19. Montes del Valle (08°40’N - 71°06’W; 2000 m asl), Estado Mérida (Tribe 1996); 20. Monte Culata (08°45’N - 71°05’W; 4000 m

  asl), Parque Nacional Sierra de la Culata, Estado Mérida (Tribe 1996); 21. Tabay (08°37’N - 71°02’W; 2450-3160

  m asl): includes: 4 km S and 6.5 km E Tabay; 6 km ESE of Middle Refuge; 2.9 km E, Mérida; 7 km SE Coromo- to; La Mucuy, camino a la Coromoto, primer refugio, Estado Mérida (MBUCV-322; Handley 1976, Tribe 1996); 22. Lourdes (08°36’N - 71°00’W; 1630 m asl),

  Estado Mérida (Tribe 1996); 23. La Carbonera (08°38’N

• 71°21’W; 2200 m asl), San Eusebio, Estado Mérida (MBUCV-323).

  
  

  Rhipidomys fulviventer elatturus

  24. 35 km S + 22 km O de San Cristóbal (Buena Vis- ta) (07°27’N - 72°26’W; 2405 m asl), Parque Nacional El Tamá, Estado Táchira (EBRG-15241, 15242, 15243, 15244, 15245, 15246, 15247); 25. Páramo del Tamá (type locality: 07°25’N - 72°26’W; 2133 m asl), Parque Nacio- nal El Tamá, Estado Táchira (Tribe 1996).

  
  

  Rhipidomys fulviventer javiersanchezi

  26. Hotel Humboldt (type locality: 10°33’N - 66°52’W; 2095 -2135 m asl; García et al. 2015), 9.4 km N de Caracas, Distrito Capital: includes: Pico Ávila, 5 km NNE de Ca- racas, cerca del Hotel Humboldt (EBRG-15248, 15249, 15250, 15252; Handley 1976, Tribe 1996). 27. Lagunazo (10°32’N - 66°50’W; 2100 m asl), Parque Nacional El Ávi- la, Distrito Capital (MHNLS-10619, 10618).

  
  

  Rhipidomys fulviventer bisbali

  1. La Trampa del Tigre (type locality: 10°24’N - 68°48’W; 1940 m asl; García et al. 2015), sector El Silen- cio, Sierra de Aroa, Estado Yaracuy (MZUC-1125, 1126).

     
     

     Rhipidomys tenuicauda

  2. 2 km N + 4 km W Caripe (cerca de San Agustín) (10°12’N - 63°32’W; 1170 -1340 m asl), Estado Mona-

  gas: includes: 2 km N + 4 km O de Caripe (La Lagu- na); Serranía de Turimiquire, cumbre cerro La Laguna, Estado Anzoátegui; Cueva del Guácharo, Caripe; San Agustín, 5 km NO de Caripe; Hacienda San Fernando;

  F. J. García, T. G. Almeida, M. Machado, M. I. Delgado-J., D. Araujo-R., O. Vásquez-P. & G. Flórez

  
  

  Monagas, San Agustín (EBRG-15259, 15260,15261,

  15262, 15263, 15264, 22872; MNHLS-8926; Tribe

  1996); 30. Cerro Espejo (10°11’N - 63°32’W; 1600 m

  asl), Caripe, Estado Monagas (MBUCV-318); 31. Las Delicias (10°11’N - 63°28’W; 1400 m asl), Caripe, Esta- do Monagas (MBUCV-319, 320); 32. Caripe (10°10’N - 63°30’W; 100 - 500 m asl), cerca de San Agustín, Estado Monagas (MBUCV-321, 324); 33. Carapas (10°12’N -

  63°56’W; 1710 m asl), Cerro Turimiquire, Estado Sucre (Tribe 1996); 34. Latal (10°10’N - 63°55’W; 945 m asl),

  Estado Sucre (Tribe 1996); 35. Los Palmales [= Palma- res] (type locality: 10°17’N - 63°45’W; Tribe, 1996), Es- tado Sucre.

  Rhipidomys wetzeli

  36. 85 km SE de El Dorado (06°38’N - 61°33’W; 75

  m asl), Estado Bolívar (EBRG-15236, 15237, 15238, 15239; Gardner 1990, Tribe 1995, 2015); 37. Churi-tepui (05°13’N - 61°54’W; 1495 m asl), Estado Bolívar (Tribe 1996, 2015); 38. Cerro Neblina, campamento II (00°50’N

• 65°59’W; 2200 m asl), 2.5 km NE del Pico Phelps, Esta- do Amazonas (MBUCV-3311; serie tipo); 39. Cerro Ne- blina, campamento VII (type locality: 00°51’N - 65°58’W; 1800 -2000 m asl; Tribe 1996), Estado Amazonas (MBU- CV-3519 to 3526; serie tipo); 40. Cerro Duida, cabecera del caño Culebra (03°34’N - 65°30’W; 1140 -1480 m asl; Tribe 2015), Estado Amazonas.