Sturnira adrianae adrianae, Molinari, Jesús, Bustos, Xiomar E., Burneo, Santiago F., Camacho, M. Alejandra, Moreno, S. Andrea & Fermín, Gustavo, 2017

Molinari, Jesús, Bustos, Xiomar E., Burneo, Santiago F., Camacho, M. Alejandra, Moreno, S. Andrea & Fermín, Gustavo, 2017, A new polytypic species of yellow-shouldered bats, genus Sturnira (Mammalia: Chiroptera: Phyllostomidae), from the Andean and coastal mountain systems of Venezuela and Colombia, Zootaxa 4243 (1), pp. 75-96 : 83-87

Sturnira adrianae adrianae new subspecies

Adriana’s Yellow-shouldered Bat

Murciélago de Charreteras de Adriana Holotype ( Fig. 4 ). An adult male (CVULA 8570), consisting of cranium, mandibles, partial postcranial skeleton, and study skin.

Type locality. Venezuela, Estado Barinas, Carretera Santo Domingo–Barinitas , 1 km frontera Mérida – Barinas: latitude, 8.865°; longitude, -70.593°; elevation, 1560 m.

Paratypes. We designate as paratypes one female ( CVULA 8770 ) from the type locality, and one male ( CVULA 8586 ) and one female ( CVULA 8585 ) from Venezuela, Estado Mérida, Sector Cucuchica , 5.8 km ENE Tovar, 8.337°, -71.701°, 930 m. Prepared as the holotype. For all the specimens referred to the species, see Appendix.

Measurements of the type material. The linear measurements (mm) and body masses (g) of the types, males first ( CVULA 8570, 8586, 8585, 8770), are: skull length, 24.7, 24.7, 23.7, 23.5; condyloincisive length, 23.1, 23.3, 22.3, 22.4; condylocanine length, 21.8, 22.1, 21.0, 21.4; postorbital breadth, 6.6, 6.5, 6.5, 6.5; braincase breadth, 11.1, 11.2, 10.8, 11.0; mastoid breadth, 12.9, 13.3, 12.8, 12.5; zygomatic breadth, 15.1, 14.8, 14.4, 14.3; maxillary toothrow length, 7.3, 7.4, 7.0, 6.9; M2-M2 breadth, 9.1, 8.8, 8.6, 8.2; dentary length, 16.7, 16.4, 15.4, 15.5; mandibular toothrow length, 8.2, 8.1, 7.9, 7.8; forearm length, 47.1, 47.0, 48.1, 44.8; third metacarpal length, 43.9, 43.2, 42.9, 40.6; fourth metacarpal length, 44.4, 43.8, 42.9, 41.0; fifth metacarpal length, 45.2, 45.2, 44.8, 40.9; total length, 76.0, 77.0, 73.0, 71.0; hind-foot length, 13.0, 16.0, 14.5, 12.0; ear length, 18.0, 18.0, 18.0, 18.0; body mass, 25.0, 29.0, 23.5, 20.5.

Diagnosis. Epaulettes (yellow shoulders) present. Lower molars with continuous lingual cusps. All four lower incisors well developed, bilobed. Upper middle incisor long, bilobed, pointed, strikingly protrudent, tip laterally diverging. Lower canine long, narrow. Upper premolars broad and long in labial view. Molars with no gaps between them. Zygomatic arch complete, not bowed outwards. Occiput low. Preorbital frontal ridges well developed. Foramen ovale touching the caudal pterygoid process.

Description. Cranial and wing size medium-large for the genus, largest for the S. oporaphilum clade ( Table 3 ). Males larger than females in cranial and wing size ( Fig. 3 ). Pelage pale grayish-brown in overall coloration: exceptions involve tawny or ochraceous browns. Fur woolly, 5–8 mm long between shoulders, 4–5 mm long on chest. Forearm, femur, and tibia furred with short and thick hairs dorsally, with short and thin hairs ventrally. Foot sparsely furred dorsally with short and thin hairs. Interfemoral membrane sparsely furred with 4–6 mm long hairs. Wing membranes grayish- to blackish-brown. Dorsal hairs with a blackish-brown basal band one-fourth to onethird their length, a pale-grayish medial band about half their length, and a grayish-brown terminal band one-sixth to one-fourth their length. Ventral hairs with a blackish-brown basal band about five-eighths their length, and a grayish-brown to pale grayish-brown terminal band about three-eighths their length. Epaulettes present. Third and fourth metacarpals of similar length. Upper middle incisor long, strikingly protrudent frontally, with two similarly broad lobes, abruptly tapering in lateral view, tip narrow and markedly diverging outwards in frontal view. Lower incisors numbering four, all well developed and bilobed. Upper canine long and robust in both sexes, moderately protrudent frontally. In lateral view, lower canine long and narrow: the posterior longitudinal ridge hidden by the shaft except for a small portion near the base of the tooth. Lower canines laterally divergent, with shafts slanted outwards. Upper toothrow relatively straight, gently arched inwards posteriorly. Upper premolars—especially the second—broad and long in labial view: labial edges highly developed. Lower molars with continuous lingual cusps: a vertical notch separating the metaconid and entoconid is absent. Adjacent upper and lower molars not separated by gaps, thus in contact with each other. Braincase broad, and markedly domed. Rostrum elongated, broad anteriorly thus providing space to accommodate broad-at-base incisors, canines, and premolars. Sagittal crest, and preorbital frontal ridges converging to it, well developed. Zygomatic arch complete, moderately open, relatively straight, converging obliquely to the rostrum. Occiput low with respect to zygomatic arches, much closer to the zygomatic plane than to its parallel epiparietal plane: the former is defined as the plane along the right and left zygomatic arches; the latter is defined as the plane, parallel to the zygomatic plane, at the level of the highest point of the saggital crest. Occiput usually rounded in dorsal and ventral views. Sphenorbital fissure elliptical. Foramen ovale subcircular, located at the base of the vertical wall (partly under this wall) of the caudal pterygoid process. Clinoid processes moderately developed, variable in size and shape.

Comparisons ( Table 3 ; Figs. 4–6 ). We compare species in phylogenetic order ( Velazco & Patterson 2013), from more to less related to S. adrianae . Within clades, we compare first with species more likely to be confused with S. adrianae . The characters of S. a. adrianae are followed by the characters (enclosed in parentheses) of the species with which it is being compared. For the S. oporaphilum clade, we use discretely varying characters defined and scored by Velazco & Patterson (2014).

Compared to S. oporaphilum : 1) largest cranial and wing size of members of the S. oporaphilum clade (medium); 2) males larger than females in cranial and wing dimensions (similar-sized); 3) pelage pale grayishbrown (dark grayish brown, or dark brown); 4) epaulettes present (inconspicuous or absent); 5) upper canine long and robust, moderately protrudent frontally (shorter and weaker, not protrudent); 6) upper middle incisor long, strikingly protrudent, abruptly tapering in lateral view, tip narrow and markedly diverging outwards in frontal view (shorter, less protrudent, gently tapering, tip broad and moderately diverging outwards); 7) upper premolars broad and long in labial view: labial edges highly developed (narrower and shorter: labial edges moderately developed); 8) rostrum elongated (shorter); 9) in lateral view, lower canine long and needle-like: posterior longitudinal ridge hidden by the shaft (short: posterior longitudinal ridge visible in the background); 10) occiput low with respect to zygomatic arches (high: equidistant to the zygomatic and epiparietal planes); 11) sphenorbital fissure elliptical (subcircular); 11) clinoid processes moderately developed (weakly developed).

Compared to S. ludovici : 1) males larger than females in wing dimensions (similar); 2) dorsal pelage pale grayish-brown (brown); 3) ventral pelage grayish-brown or pale grayish-brown (dark brown); 4) upper middle incisor long, strikingly protrudent, abruptly tapering in lateral view, tip narrow and markedly diverging outwards in frontal view (shorter, less protrudent, gently tapering, tip broad and moderately diverging outwards); 5) upper canine protrudent frontally (not protrudent); 6) braincase broad, and markedly domed (narrower, moderately domed); 7) sphenorbital fissure elliptical (subcircular).

Compared to S. burtonlimi : 1) largest cranial and wing size of members of the S. oporaphilum clade (smallest); 2) ventral pelage grayish-brown or pale grayish-brown (dark gray); 3) third and fourth metacarpals of similar length (fourth shorter); 4) upper middle incisor bilobed, tip markedly diverging (unilobed, tip moderately diverging); 5) sphenorbital fissure elliptical (subcircular).

Compared to S. hondurensis : 1) largest cranial and wing size of members of the S. oporaphilum clade (small); 2) ventral fur with two color bands (one); 3) third and fourth metacarpals of similar length (fourth shorter); 4) upper middle incisor long, strikingly protrudent, bilobed, abruptly tapering in lateral view (shorter, not protrudent, unilobed, gently tapering); 5) upper canine long (shorter); 6) rostrum and palate broad (narrower); 7) in lateral view, lower canine long and needle-like: posterior longitudinal ridge hidden by the shaft (shorter: posterior longitudinal ridge visible in the background); 8) braincase broad (narrower); 9) sphenorbital fissure elliptical (subcircular); 10) clinoid processes present (absent).

Compared to S. mordax (Goodwin) , and S. koopmanhilli McCarthy et al. : 1) upper middle incisor bilobed, both lobes nearly equal in breadth, pointed, with a markedly diverging tip (weakly bilobed, inner lobe broader than outer, square- or round-tipped, moderately diverging tip); 2) upper premolars broad and long (narrower and shorter in S. koopmanhilli ); 3) adjacent upper and lower molars not separated by gaps (separated in S. koopmanhilli ); 4) rostrum and palate broad (narrower); 5) braincase broad and domed (narrower, moderately domed).

Compared to S. erythromos (Tschudi) , S. bogotensis , and S. sorianoi Sánchez-Hernández et al. : 1) cranial and wing size medium-large for the genus (medium to small. Mean body mass of Venezuelan specimens: S. erythromos , 15.4 g; S. bogotensis , 18.8 g); 2) upper middle incisor long, strikingly protrudent, bilobed, tip narrow in frontal view (short, not protrudent, unilobed or indistinctly bilobed, tip broad); 3) upper toothrow relatively straight (upper dentition horseshoe-shaped in occlusal view); 4) rostrum and palate elongated (much shorter); 5) zygomatic arch moderately open (wide open). The last four differences are also evident when comparing the often confused pair S. oporaphilum and S. bogotensis .

Compared to S. tildae de la Torre : 1) upper middle incisor long, strikingly protrudent, bilobed, tip narrow and markedly diverging outwards in frontal view (short, not protrudent, weakly bilobed, tip broad and barely diverging); 2) lower incisors bilobed (faintly trilobed); 3) lower molars with continuous lingual cusps (metaconid and entoconid separated by a moderately developed vertical notch).

Compared to S. magna de la Torre : 1) cranial and wing size medium-large for the genus (large: mean body mass, 43.1 g; Tamsitt & Häuser 1985); 2) upper middle incisor narrow-tipped (broad-tipped).

Compared to S. perla Jarrín-V. & Kunz: 1) cranial and wing size medium-large for the genus (medium); 2) zygomatic arch moderately open, relatively straight, converging obliquely to the rostrum (wide open, markedly bowed outwards, not converging to the rostrum).

Compared to S. lilium , S. parvidens Goldman , S. angeli de la Torre , S. paulsoni de la Torre & Schwartz , S. luisi Davis , S. mistratensis Contreras Vega & Cadena , S. bakeri Velazco & Patterson , and S. new species 3 ( Velazco & Patterson 2013): 1) cranial and wing size medium-large for the genus (medium); 2) lower incisors bilobed (trilobed); 3) lower molars with continuous lingual cusps (metaconid and entoconid separated by a deep vertical notch).

Compared to S. aratathomasi Peterson & Tamsitt : 1) cranial and wing size medium-large for the genus (largest: mean body mass, 50.4 g; Soriano & Molinari 1987); 2) lower molars with continuous lingual cusps (metaconid and entoconid separated by a deep vertical notch).

Compared to S. nana Gardner & O'Neill , and S. bidens (Thomas) : 1) cranial and wing size medium-large for the genus (medium to small; mean body mass of S. bidens , 17.6 g, Molinari & Soriano 1987; S. nana much smaller); 2) epaulettes present (absent); 3) All four lower incisors well developed (outer lower incisors absent or vestigial); 4) adjacent upper and lower molars not separated by gaps (separated); 5) zygomatic arch complete (often incomplete).

Distribution ( Fig. 1 ). Known from all the Andean and coastal mountain systems of Venezuela, except those east of the Unare Depression. Presumably, also distributed throughout the Cordillera Oriental in Colombia: 1) our samples from the Venezuelan side of the Cordillera Oriental are from localities near or almost exactly on the border of both nations; 2) populations from the Venezuelan slope of the Sierra de Perijá and Cordillera Oriental are necessarily connected by populations occurring in mountains lying entirely in Colombian territory; 3) S. “ ludovici ” has been reported from the Colombian slope of the Sierra de Perijá ( Muñoz-Saba 2009), and eastern foothills of the Sierra Nevada de Santa Marta ( Hershkovitz 1949).

Etymology. The epithet adrianae , a feminine noun in the genitive case, is dedicated to the memory of the Colombian-Venezuelan bat biologist, Adriana Ruiz, 1971–2012. Adriana was a charismatic, imaginative, and dedicated colleague. She published 14 papers and book chapters. Owing to her untimely departure, much of her most valuable research was left unpublished. Adriana had a particularly keen interest in species of Sturnira . We are privileged to name after her a member of the genus wandering in the environments in which she so joyfully conducted much of her field work.

Figures

FIGURE 1. Map of Venezuela and neighboring Colombia showing the collection localities of specimens of Sturnira adrianae, new species. Solid circles correspond to S. a. adrianae. Solid triangles correspond to S. a. caripana. Abbreviations are: SA, Sierra de Aroa; SB, Sierra de Bobare; SC, Sistema Coriano; SL, Sierra de San Luis (part of SC); SM, Sierra Nevada de Santa Marta; 1, Táchira Depression; 2, Lara Depression; 3, Yaracuy Depression; 4, Unare Depression. For locality data, see Appendix.

FIGURE 3. Box-and-whisker plots summarizing the cranial and wing dimensions of Sturnira oporaphilum, S. adrianae adrianae, and S. a. caripana. Plots A and B consider the single measurements most representative of cranial and wing dimensions. Plots C and D consider all measurements by displaying specimen scores in the two axes of a Multiple Discriminant Analysis (MDA). In this MDA, the first axis accounts for 82.3 % and the second axis for 17.7 % of the variance. Crosses and vertical lines within gray boxes represent, respectively, means and medians. Gray box widths span the interval between the 25 th and 75 th percentiles, containing the middle 50 % of the data points. Horizontal lines, or “ whiskers ”, extend this interval to the 10 th and 90 th percentiles, containing 80 % of the data points. At least nine data points are required to compute the 10 th and 90 th percentiles, hence no whiskers are plotted for S. a. caripana. Open circles represent potential outliers. Sample sizes indicated after taxon names.

FIGURE 4. Lateral, dorsal, and ventral views of the crania, and lateral views of the mandibles of the holotypes. Left: Sturnira adrianae adrianae (male, CVULA 8570). Right: S. a. caripana (male, CVULA 8593).

FIGURE 6. From top to bottom, frontal views of the upper incisors and canines, occlusal view of the upper dentition, and frontal view of the lower incisors and canines of: A) Sturnira adrianae adrianae (male, CVULA 7938); B) S. a. caripana (male, CVULA 8590); C) S. oporaphilum (male, QCAZ 2300); and D) S. ludovici (male, QCAZ 1644).