Cryptotriton necopinus, Mccranie, James R. & Rovito, Sean M., 2014

Mccranie, James R. & Rovito, Sean M., 2014, New species of salamander (Caudata: Plethodontidae: Cryptotriton) from Quebrada Cataguana, Francisco Morazán, Honduras, with comments on the taxonomic status of Cryptotriton wakei, Zootaxa 3795 (1), pp. 61-70 : 63-67

Cryptotriton necopinus sp. nov.

Cataguana Hidden Salamander Salamandra Escondida de Cataguana ( Figs. 1 , 2 )

Holotype. MVZ 269392, an adult male from Quebrada Cataguana , 15.004166°, -87.100555° (WGS84), 1,880 m elev., collected 12 June 2013 by James R. McCranie.

Geographic distribution. Cryptotriton necopinus is known only from the type locality, at a moderate elevation in Parque Nacional Montaña de Yoro in north-central Honduras ( Fig. 3 ).

Diagnosis. Cryptotriton necopinus is distinguished from C. nasalis (Dunn) and C. wakei (Campbell & Smith) , its nearest known geographical neighbors (but see Remarks), in having the inside of the nostril opening a much paler color than the adjacent head, a HFW/SVL of 0.049, and a TL/SVL of ca. 1.00 in the single male (versus inside of nostril opening of similar color as remainder of head in C. nasalis and C. wakei , HFW/SVL 0.058–0.091 in male C. nasalis and 0.090 in single female C. wakei , and TL/SVL 1.14–1.35 in male C. nasalis and 1.18 in single female C. wakei ); from C. sierraminensis Vásquez-Almazán, Rovito, Good & Wake by having a brown venter (yellow in C. sierraminensis ) and relatively narrower feet (HFW/SVL 0.049 vs. 0.086 in C. sierraminensis ); from C. alvarezdeltoroi (Papenfuss & Wake) by having a shorter tail (TL/SVL ca. 1.00 vs. 1.08–1.21 in C. alvarezdeltoroi ) and narrower feet (HFW/SVL 0.049 vs. 0.080 in C. alvarezdeltoroi ); from C. monzoni (Campbell & Smith) by having more premaxillary plus maxillary teeth (59 in male holotype of C. necopinus vs. 50 in female holotype of C. monzoni ) and by its larger size (26.4 mm SVL vs. 22.3 mm SVL in C. monzoni ); from C. veraepacis (Lynch & Wake) by its shorter tail (TL/SVL ca. 1.00 vs. 1.26–1.43 in male C. veraepacis ), more ovoid nostril (NL/ NW 1.60 vs. 1.03–1.32 in C. veraepacis ), and more numerous prevomerine teeth (13 vs. 8–11 in C. veraepacis ); from all other species of Cryptotriton by having frontal processes of premaxilla separate along their entire length. Cryptotriton necopinus also differs from all other described species of Cryptotriton (with the possible exception of the genetically unknown C. wakei ) by large differences in mitochondrial DNA sequence (see below).

Description of holotype. An adult male with a SVL of 26.4 mm; HL 5.3, HL/SVL 0.201; HW 3.4, HW/SVL 0.129; TL 26.0 (plus tail tip removed for tissues), TL/SVL 0.985+; HLL 6.8, HLL/SVL 0.258; FLL 5.3, FLL/SVL 0.201; CLL 12.1, CLL/SVL 0.458; HFW 1.3, HFW/SVL 0.049; FFW 0.7, FFW/SVL 0.027; NL 0.8, NL/SVL 0.030; NW 0.5; NL/NW 1.6; head depth 1.7; eyelid length 1.4; eyelid width 0.4; anterior rim of orbit to snout 1.3; interorbital distance 0.5; snout to forelimb distance 7.8; distance between external nares 0.3; projection of snout beyond mandible 0.2; mental gland width 0.5, length 0.4; parotoid gland width 0.4, length 0.4; snout to anterior angle of vent distance 25.8; axilla to groin distance 13.7; tail depth at base 1.9; tail width at base 2.0; length of third toe on hind foot 1.9; length of fifth toe on hind foot 1.6.

Snout truncate in dorsal aspect, broadly rounded in profile; nostrils greatly enlarged; labial protuberances well developed; mental gland oval-shaped, flat, gland not paler color than surrounding areas; eyes protuberant, barely visible beyond margin of jaw when viewed from below; postorbital groove shallow, only visible posteriorly above posterior level of jaws, turning sharply ventrally to connect with gular fold, no other groove visible; head well demarcated from trunk; parotoid glands evident, but not particularly swollen; sublingual fold present; maxillary teeth 55 (both sides combined), extending to level beyond center of orbit; prevomerine teeth 23 (both sides combined), in long, single, arched series extending to level of inner edge of choanae; premaxillary teeth 4, enlarged, located just posterior to lip and slightly offset from maxillary series; costal grooves 13; tail laterally compressed, slightly constricted at base; limbs slender, relatively long, adpressed limbs separated by limb interval of 2.5 costal folds; digits differentiated, with about two phalanges of Digit III between Digits II–III on forelimbs free of webbing, with 2.5 phalanges of Digit III between Digits III–IV on hind limbs free of webbing; digits bluntly rounded, bearing well-developed subdigital pads; relative length of digits on forelimbs I <II = IV <III, those on hind limbs I <V <II <IV<III; postiliac glands not evident; cloacal papillae present.

Color in life: dorsum Clay Color (18) with Warm Sepia (40) flecking and mottling, scattered Poppy Red (63) flecking also present; Robin Rufous (29) broad middorsal stripe extending from level of posterior insertion of forelimbs to level of anterior insertions of hind limbs; lateral surface of body Warm Sepia; top of head Walnut Brown (27) with Warm Sepia flecking; dorsal surfaces of limbs Clay Color with Warm Sepia mottling, Poppy Red tinge also present on forelimbs and shanks of hind limbs; dorsal surfaces of pads and ventral surfaces of digits on fore- and hind limbs Poppy Red; dorsal surface of tail Robin Rufous; rim of nostril opening Walnut Brown with interior Salmon Color (58); all ventral surfaces Walnut Brown with tiny pale brown flecking under head; iris Clay Color above, Walnut Brown below.

Color in alcohol (about three weeks after transferring from one week in 10% formalin): dorsolateral and lateral surfaces of body dark brown with pale brown flecking; middorsal swath on body brown with dark brown flecking; top of head and nuchal region brown with dark brown interorbital bar and mottling in nuchal region; dorsal surface of tail brown at base, quickly becoming dark brown for remainder of length; ventral and subcaudal surfaces pale brown with numerous dark brown flecks, flecking becoming more dense on posterior two-thirds of subcaudal surface; inside of nostril opening pale brown.

Osteology. An X-ray of the holotype of Cryptotriton necopinus showed that the prefrontal bone appears to be pierced by the nasolacrimal duct ( Fig. 4 ), as in C. veraepacis ( Lynch & Wake 1978, Fig. 2 ). Previously examined individuals of C. alvarezdeltoroi , C. nasalis , and C. sierraminensis have a prefrontal evacuated along the anterior edge rather than pierced, although one individual of C. sierraminensis shows both character states ( Lynch & Wake 1978; Vásquez-Almazán et al. 2009). The septomaxillary bone is absent, as in all other species of Cryptotriton . The frontal processes of the premaxillary bone arise separately and are separated along their entire length, whereas all other described species of Cryptotriton have processes that are fused at the base and separated posteriorly ( Lynch & Wake 1978). The holotype lacks a preorbital process on the vomer, like all Cryptotriton except C. sierraminensis . No tibial spur is evident.

Habitat. The holotype of Cryptotriton necopinus was collected at 1,880 m elevation on a leaf of a broadleaf shrub about 1 m above the ground and growing about 3 m from the Quebrada Cataguana . The specimen was slowly crawling on the leaf about 3 hours after dark, but made short jerky movements when the flashlight was shown directly on the animal. About a 30 minute moderately heavy rainfall occurred just prior to nightfall that evening and the broadleaf vegetation where the holotype was found was still wet. The locality lies in the Lower Montane Wet Forest formation of Holdridge (1967) and has a closed canopy at the collection site; however, the quebrada ca. 200 m above that point has been completely denuded and now flows through homesteads and pastures. Other salamanders collected in the vicinity of Quebrada Cataguana were Bolitoglossa cataguana Townsend, Butler, Wilson , & Austin and Nototriton lignicola McCranie & Wilson.

Etymology. The specific name necopinus is a Latin adjective for unexpected. That name has two meanings in connection with the finding of this new species. Firstly, finding a member of Cryptotriton about 125 km SE of its previous eastern most known locality was certainly unexpected. Secondly, a group of seven collectors had spent six days and five nights in the area searching for amphibians and reptiles during March 2007 ( Townsend et al. 2007) and at least two of those collectors had spent about a week in the area during 2006 (Townsend & Wilson 2009, Townsend et al. 2009). Thus, it was also unexpected to find an undescribed salamander species at the locality in such a short time period (two days and nights) after so many productive man-hours were previously spent there.

Molecular analyses. The phylogeny of Cryptotriton based on two mitochondrial genes estimated using maximum likelihood and Bayesian inference is largely unresolved ( Fig. 5 ). Tamura-Nei (TN930 genetic distances between C. necopinus and other species of Cryptotriton are fairly large (Table 2). For 16S, TN93 distances range from 0.042 (to C. nasalis ) to 0.074 (to C. monzoni ); for cytb, distances range from 0.136 (to C. veraepacis ) to 0.208 (to C. alvarezdeltoroi ). Uncorrected p-distances for 16S range from 0.041 (to C. nasalis ) to 0.068 (to C. monzoni ); for cytb, they range from 0.126 (to C. nasalis ) to 0.192 (to C. alvarezdeltoroi ).

Figures

FIGURE 1. Adult male holotype of Cryptotriton necopinus sp. nov. (MVZ 269392), SVL 26.4 mm. Photograph by J. R. McCranie.

FIGURE 2. Adult male holotype of Cryptotriton necopinus sp. nov. (MVZ 269392), showing the nostril opening color in life. Photograph by J. R. McCranie.

FIGURE 3. Map of southern Mexico, Guatemala, and western Honduras showing the known collecting localities for the species of Cryptotriton.

FIGURE 4. Illustration of select elements of the anterior portion of the skull of the holotype of Cryptotriton necopinus from an X-ray, following Lynch and Wake (1978). Heavy lines, nasal bone; fine lines, internasal fontanelle; stipple, cartilaginous nasal capsule; blackened area, opening in nasal capsule for external naris. Arrow indicates foramen where prefrontal bone is pierced by nasolacrimal duct. Maxilla and premaxilla drawn with dotted lines where they pass beneath the nasal capsule. Nasal bone on left side of skull and anterior edge of frontal bones not illustrated due to indistinctness on X-ray.

FIGURE 5. Phylogenetic tree of six named species of Middle American Cryptotriton from a maximum likelihood (ML) analysis of DNA sequences of two mitochondrial genes (16 S and cytb). Support values above branches are bootstrap values from ML analysis, and values below branches are posterior probabilities from Bayesian analysis. Support values below 50 (bootstrap) or 0.5 (posterior probability) are not shown. A scale bar is included at the bottom left in units of substitutions per site.