Fig 1.
Photographs of the four species of Chiropterotriton examined in this study.
(A) C. dimidiatus (adult SVL = approx. 25 mm); (B) C. magnipes (adult SVL = approx. 55 mm); (C) C. priscus (adult SVL = approx. 40 mm); (D) C. lavae (adult SVL = approx. 30 mm). Photos reprinted under a CC BY license, with permission from Sean Rovito.
Fig 2.
Chiropterotriton magnipes skull.
Drawings of dorsal (a) and ventral (b) aspects of the skull of Chiropterotriton magnipes (MVZ 129021). Stippled areas represent cartilage. Posterior patch of vomerine teeth is outlined. Abbreviations: fr = frontal, mx = maxilla, n = nasal, nlc = nasolacrimal canal, oc = otic capsule, opl = opercular plate, osph = orbitosphenoid, pa = parietal, pat = parietal tab, pmx = premaxilla, prf = prefrontal, psph = parasphenoid, ptrp = pterygoid process, q = quadrate, sm = septomaxilla, sq = squamosal, v = vomer, vpop = vomer preorbital process, pvtp = posterior vomerine tooth patch.
Fig 3.
Chiropterotriton priscus skull.
Drawings of dorsal (a) and ventral (b) aspects of the skull of Chiropterotriton priscus (MVZ 163887). Stippled areas represent cartilage. Elements as labeled in Fig 1.
Fig 4.
Drawings of dorsal (a) and ventral (b) aspects of the skull of Chiropterotriton lavae (MVZ 171898). Stippled areas represent cartilage. Elements as labeled in Fig 1.
Fig 5.
Chiropterotriton dimidiatus skull.
Drawings of dorsal (a) and ventral (b) aspects of the skull of Chiropterotriton dimidiatus (MVZ 103967). Stippled areas represent cartilage. Elements as labeled in Fig 1.
Fig 6.
Chiropterotriton magnipes feet.
Drawings of front, left (a) and rear, left (b) feet of Chiropterotriton magnipes (MVZ 129013), showing skeletal elements and the extent of interdigital webbing. Dorsal view; stippled areas represent cartilage. Abbreviations: c = centrale, d = distal carpals and tarsals, f = fibulare, fi = fibula, i = intermedium, mc = metacarplas, mt = metatarsals, r = radiale, ra = radius, t = tibiale, ti = tibia, u = ulnare, ul = ulna, y = element y.
Fig 7.
Chiropterotriton priscus feet.
Drawings of front, left (a) and rear, left (b) feet of Chiropterotriton priscus (MVZ 192794), showing skeletal elements and the extent of interdigital webbing. Dorsal view; stippled areas represent cartilage. Elements as labeled in Fig 5.
Fig 8.
Drawings of front, left (a) and rear, left (b) feet of Chiropterotriton lavae (MVZ 171898), showing skeletal elements and the extent of interdigital webbing. Dorsal view; stippled areas represent cartilage. Elements as labeled in Fig 5.
Fig 9.
Chiropterotriton dimidiatus feet.
Drawings of front, left (a) and rear, left (b) feet of Chiropterotriton dimidiatus (MVZ 185965), showing skeletal elements and the extent of interdigital webbing. Dorsal view; stippled areas represent cartilage. Elements as labeled in Fig 5.
Fig 10.
Frontoparietal fontanelle development.
Three degrees of development of the paired frontal and parietal bones which result in the frontoparietal fontanelle being extensive (a), reduced (b), or absent (c) in Chiropterotrition. Osteological character 8.
Fig 11.
Five states of tibial spur development in Chiropterotriton: (a) absent, tibia smooth; (b) absent, tibial ridge; (c) present, detached; (d) present, attached; (e) present, attached with foramen. Osteological character 16.
Table 1.
Frequency (%) of osteological character variation in the anterior skull.
Table 2.
Frequency (%) of osteological character variation in the posterior skull.
Table 3.
Osteological character variation in the ventral skull.
Table 4.
Frequency (%) of post-cranial osteological character variation.
Fig 12.
Drawings of dorsal (a) and ventral (b) aspects of the skull of Pseudoeurycea leprosa (MVZ 147092). Stippled areas represent cartilage. Elements as labeled in Fig 1.
Fig 13.
Silhouette drawings illustrating the size differences among the four species of Chiropterotriton examined in this study. Rendered from a single photograph of the dorsal view of adult preserved specimens. (a) C. dimidiatus (MVZ 114511; SVL = 25 mm, total length = 50 mm); (b) C. lavae (MVZ 171876; SVL = 34 mm, total length = 69 mm); (c) C. priscus (MVZ 138885; SVL = 46 mm, total length = 86 mm); (d) C. magnipes (MVZ 129016; SVL = 52 mm, total length = 108 mm).
Table 5.
Frequency (%) of right-left asymmetry in paired osteological characters.
Fig 14.
Drawing of left, rear foot of Pseudoeurycea leprosa (MVZ 147092), showing skeletal elements and the extent of interdigital webbing. Dorsal view; stippled areas represent cartilage. Elements as labeled in Fig 5.
Table 6.
Skull robustness.
Fig 15.
Four hypotheses representing potential explanations of the pattern of skull robustness seen in the four species of Chiropterotriton examined in this study and the morphological groupings predicted by each hypothesis. Skull robustness: l = low, i = intermediate, h = high.
Fig 16.
Chiropterotrition priscus body shape.
Photograph showing the strikingly similar external appearance of (a) Chiropterotrition priscus (MVZ 138885) and certain members of the genus Pseudoeurycea [(b) P. leprosa (MVZ 132796)].
Fig 17.
Anomalous Chiropterotriton priscus foot.
Anomalous morphology of the right, hind foot of a single specimen of Chiropterotriton priscus (MVZ 138883). Dorsal view; distal tarsals labeled.