Bolitoglossa aureogularis, Boza-Oviedo, Eduardo, Rovito, Sean M., Chaves, Gerardo, García-Rodríguez, Adrián, Artavia, Luis G., Bolaños, Federico & Wake, David B., 2012

Boza-Oviedo, Eduardo, Rovito, Sean M., Chaves, Gerardo, García-Rodríguez, Adrián, Artavia, Luis G., Bolaños, Federico & Wake, David B., 2012, Salamanders from the eastern Cordillera de Talamanca, Costa Rica, with descriptions of five new species (Plethodontidae: Bolitoglossa, Nototriton, and Oedipina) and natural history notes from recent expeditions, Zootaxa 3309, pp. 36-61 : 45-46

Bolitoglossa aureogularis sp. nov.

Yellow-throated Web-footed Salamander Figure 3

Holotype. UCR 19893, an adult female from along the Río Coén on the Trans-Talamancan trail near Cerro Arbolado (9.3925º N, 83.2119º W) at an elevation of 1680 m approximately 8 km N of the continental divide, Provincia de Limón, Costa Rica, collected by Eduardo Boza-Oviedo on 1 March 2007.

Paratypes. UCR 19892, same data as holotype; UCR 19857–59 (3 specimens), 9.3416º N, 83.232º W, 2102 m, in headwaters area of Río Coén, about 2 km N continental divide, Provincia de Limón, Costa Rica, collected by Eduardo Boza-Oviedo on 22 February 2007.

Diagnosis. Assigned to Bolitoglossa because it lacks a sublingual fold ( Wake & Elias 1983), and to subgenus Eladinea based on mtDNA sequence data. A medium-sized member of the genus Bolitoglossa (subgenus Eladinea) with moderate webbing of the digits of the hands and feet that differs from all other species in the genus by its unique coloration ( Fig. 3 ) of reddish tan to yellow dorsal coloration with black flanks and a venter marked by bright yellow gular and yellow-brown chest regions, with a pair of dirty white patches on the ventrolateral surfaces of the posterior venter. In comparison to members of the B. robinsoni complex , this species is much smaller and more slender, in addition to the coloration differences.

Description. A slender species of moderate size compared to other members of its genus. SL of holotype, the only adult specimen available (48.8 mm), nearly identical to that of its close geographic neighbor Bolitoglossa splendida and close to mean value of such Talamancan species as B. pesrubra , B. subpalmata ( García-París et al. 2008) , and B. gomezi ( Wake et al. 2007). Tail slender but relatively short (tip broken). Head narrow ( Wake & Brame 1972); SL/HW = 8.0. Relatively short snout broadly rounded. Small nostrils are typical for this genus. Nasolabial protuberances not pronounced; paler than surroundings and appear to be pigmented with white. Eyes small, do not protrude beyond lateral margins of head, not visible in ventral view. Teeth moderate in size and numerous (57 MT, 6 PMT, 27 VT). Limbs relatively short with LI of 3.5. Hands and feet moderate in size; FW = 5.1 mm. Digits well-differentiated but short and knob-like with distinct subdigital pads on longer digits. Webbing, reaching between first and second phalangeal articulations of longest digits; webbing more extensive in foot than in hand. Fingers, in order of decreasing length, are 3-4-2-1; toes are 3-4-2-5-1. Postiliac glands pale and inconspicuous.

Measurements (in mm), limb interval and tooth counts of the female holotype ( Table 2 ). HW 6.1, SG 10.1, HD 2.3, EW 1.3, EL 2.7, ES 1.7, ED 2.2, IC 3.5, IO 2.4, SF 12.5, IN 1.5, SP 0.4, SW 4.8, SL 48.8, SAV 45.0, AX 26.2, LI 6.5, FLL 9.3, HLL 10.2, HAW 3.3, FW 4.3, T5 0.9, T3 1.4. Numbers of teeth: PMT 6, MT 29/28, VT 13/14.

Coloration of the holotype in life ( Fig. 3 ). Dorsal coloration golden-tan with some bright highlights on dorsolateral regions and with some narrow streaks of dark brown. Golden-tan coloration in form of broad band extending from snout onto tail. Tail becomes increasingly reddish brown posteriorly. Lateral surfaces dark brown with numerous white speckles. Dark coloration forms lateral margin of dorsal band and continues onto tail and forward all the way to eye and is present almost to tip of snout. Dark coloration extends to area above limb insertions so light band does not contact limbs. Dorsal surfaces of limbs similar to dorsal band in color. White pigment present ventrolaterally along trunk and becomes prominent on venter, where pair of lightly colored patches is separated by region of dark pigmentation. Gular area bright yellow, which becomes golden on chest before fading into darker color in midtrunk region. Venter of tail speckled with white and tan spots. Iris golden.

Habitat and range. The species is known from two nearby localities on the Caribbean slope of the Cordillera de Talamanca, both with mature cloud forest similar to the habitat at the type locality of Bolitoglossa splendida . The first locality is at ca. 2100 m elevation, 700 m from the nearest stream; the second, the type locality, is located at 1680 m elevation near the river edge.

Variation. There are four paratypes but only one approaches maturity in size. All specimens show coloration typical of the holotype, but some are more reddish gold dorsally and they are covered with tiny white speckles. Even the smallest individual (UCR 19858, 9.2 mm SL) displays the characteristic ventral coloration. This is a slen- der species with a small, narrow head and slender trunk and tail.

Etymology. The species name is derived from aurea (L.), golden, and gula (L.), throat, in recognition of the unusual bright yellow coloration of the gular and chest regions of this species.

Natural history and behavioral observations. The specimens from the first site were inactive in bromeliads (2.8–6.2 m above ground) during daytime, one in a cavity formed by the bromeliad roots in the trunk of the tree and the other two inside the leaves. All were in different plants in two trees, with two found in separate branches of the same tree; the temperature of the retreats was 12 °C with an air temperature of 15 °C. The juvenile and holotype from the second locality were found active at night on low vegetation or in the leaf litter (0–1.45 m), 1.8–3.7 m from the river with an air temperature of 15–18 °C during the observation period. Behavioral observations were made from 20:00–00:03 before collecting both specimens. The juvenile moved within the Araceae leaf where it was found but never went away. The adult female (holotype) climbed to the top of two shrubs and one palm seedling and moved through the leaf litter between plants. On two occasions, it held up a third of its body off surface of the leaf, and sometimes used its tail as a prehensile organ when moving along steams.

Figures

FIGURE 3. A) Dorsal and B) ventral views of holotype (UCR 19893) of Bolitoglossa aureogularis in life. C) Paratype (UCR 19857) of B. aureogularis in life. D) Dorsal view of right hand and E) right foot of holotype. Photos A, B and C by E. Boza-Oviedo and Roney Samaniego, D and E by Adrián García-Rodríguez. The bar in hand and feet are 1 mm length.