Pristimantis leptolophus

González-Durán, Gustavo A., Targino, Mariane, Rada, Marco & Grant, Taran, 2017, Phylogenetic relationships and morphology of the Pristimantis leptolophus species group (Amphibia: Anura: Brachycephaloidea), with the recognition of a new species group in Pristimantis Jiménez de la Espada, 1870, Zootaxa 4243 (1) : -

Pristimantis leptolophus species group

Content ( Fig. 2 and 3 ). Nine named species, six unnamed species, five in process of description: Pristimantis acatallelus ( Lynch and Ruiz-Carranza, 1983) , P. leptolophus ( Lynch, 1980) , P. lasalleorum ( Lynch, 1995) , P. maculosus ( Lynch, 1991) , P. parectatus ( Lynch and Rueda-Almonacid, 1998) , P. peraticus ( Lynch, 1980) , P. scoloblepharus ( Lynch, 1991) , P. stictus González-Durán, 2016 , P. uranobates ( Lynch, 1991) , Pristimantis sp. 1, Pristimantis sp. 2, Pristimantis sp. 3, Pristimantis sp. 4, Pristimantis sp. 5 and Pristimantis sp. 6.

Distribution. Cordillera Central (Puracé National Park to Parámos de Belmira, 2300–3900 m) and Cordillera Occidental (Munchique National Park to Páramo de Urrao, 2000–3850 m) of Colombia.

Morphological diagnosis. The Pristimantis leptolophus group is diagnosed by the following morphological character-states: Males with vocal slits (except Pristimantis sp. 1). Vocal sac internal (except in P. acatalellus P. leptolophus and Pristimantis sp. 3). Dorsolateral folds or scapular ridges present. Ventral skin coarsely areolate. Ulnar tubercles present. Heel tubercle and tubercles on outer edge of tarsus present. Inner tarsal fold short. Eyelid tubercles conical, subconical or small warts. Finger I shorter than Finger II. Digital discs expanded except on Finger I, which is narrow. Toe V much longer than Toe III, almost reaching distal edge of distal subarticular tubercle on Toe IV. Digital discs on toes expanded (narrow on Toe I in P. peraticus ). Frontoparietal fenestra almost entirely hidden, visible only between the narrow space between the parallel frontoparietals, frontoparietal crests absent ( Fig. 4 b, d, e). Anterior margin of optic fenestra ossified ( Fig. 4 c, e) (cartilaginous in P. acatallelus and Pristimantis sp. 1 as in Fig. 4 a, polymorphic in P. maculosus , P. peraticus , P. scoloblepharus , P. uranobates as in Fig. 4 e). Dorsal fascia slip (DF) of m. depressor mandibulae absent (present in P. scoloblepharus , Pristimantis sp. 1, and Pristimantis sp. 5). Squamosal flap of m. depressor mandibulae short, overlapping otic ramus of squamosal (SQ). Posterior fibers of squamosal slip of m. depressor mandibulae originating from m. levator posterior longus at level of otic ramus of squamosal (SQp).

Only one character-state is proposed as putative synapomorphy: 1) Posterior fibers of squamosal slip of m. depressor mandibulae (SQp) at the level of otic ramus of squamosal ( Table 2 , Fig. 5 d, f).

Morphological characterization. External morphology. Species of the Pristimantis leptolophus group are small–medium in size, SVL <27.8 mm in females and 20.3 mm in males (except P. acatallelus , maximum SVL = 31.7 mm in females, 27.2 mm in males; Lynch and Ruiz-Carranza, 1983). Snout short, subacuminate or round in dorsal view, rounded or protruding in lateral profile. Tip of snout with small papilla in some specimens, mostly males ( P. leptolophus , P. stictus , Pristimantis sp. 3, and P. scoloblepharus ). Canthus rostralis concave. Adult males with vocal slits (absent in Pristimantis sp. 1), vocal sac internal (external in P. acatalellus , P. leptolophus , Pristimantis sp. 3). Nuptial pads on Finger I present in P. lasalleorum , P. maculosus , P. scoloblepharus , P. uranobates , Pristimantis sp. 1, and Pristimantis sp. 4, absent in P. acatallelus , P. leptolophus , P. parectatus P. peraticus , P. stictus , Pristimantis sp. 2, Pristimantis sp. 3, and Pristimantis sp. 5. Dorsolateral folds complete, thick in P. uranobates , P. scoloblepharus , P. lasalleorum , Pristimantis sp. 4, and Pristimantis sp. 5, thin in P. acatallelus , P. stictus , P. leptolophus ; polymorphic in P. parectatus , P. peraticus , Pristimantis sp. 3; incomplete, row of tubercles reaching level of sacrum in P. maculosus and Pristimantis sp. 2 (polymorphic in P. parectatus ; only scapular ridges present in Pristimantis sp. 1). Ventral skin coarsely areolate. Ulnar tubercles small, subconical. Tubercles present on heel and outer edge of tarsus. Inner tarsal fold short. Supernumerary plantar tubercles present. Upper eyelid tubercles conical ( P. lasalleorum , P. parectatus , P. scoloblepharus and P. uranobates ), subconical ( P. leptolophus , P. peraticus , Pristimantis sp. 1, Pristimantis sp. 2, Pristimantis sp. 3, Pristimantis sp. 4 and Pristimantis sp. 5), or forming small warts ( P. maculosus ). Finger I shorter than Finger II, fingers with expanded round digital discs, except Finger I. Relative length of fingers: I <II <IV <III. Lateral fringes on fingers and toes present (less developed in Pristimantis sp. 3, absent in P. parectatus ). Length of toes IV> V> III> II> I. Toe V is much longer than toe III, extending near distal edge of distal subarticular tubercle on Toe IV. Digital discs expanded and round (except on toe I in P. peraticus ).

Cranium ( Fig. 4 ). In dorsal view, the sphenethmoid is concave posteriorly and hidden dorsally by the frontoparietal. Anteriorly, it reaches, but is not overlapped, by the nasals (except in Pristimantis acatallelus and Pristimantis sp. 1, Fig. 4 b). In ventral view, the anterior margin of optic fenestra is ossified (cartilaginous in P. acatallelus and Pristimantis sp. 1, Fig. 4 a, polymorphic in P. maculosus , P. peraticus , P. scoloblepharus , and P. uranobates , Fig. 4 e). Anteroventrally, it is overlapped by the vomers. The nasals are separated medially ( Fig. 4 d, e) (except in P. acatallelus and Pristimantis sp. 1, in which they are in contact, Fig. 4 b). The maxillary process of the nasal does not approximate the preorbital process of the maxilla. The frontoparietal crests are absent and the frontoparietal fontanelle is almost hidden ( Fig. 4 b, d, f). Posterolaterally, the frontoparietal extends to the level of, but do not overlap, the epiotic eminence of the prootic ( Fig. 4 b, d, f). The frontoparietal and prootic are separate, not fused. The cultriform process of the parasphenoid does not reach the level of the palatines and vomers; it almost reaches the palatines, lying just posterior to them ( Fig. 4 a, c, e). The otic ramus of the squamosal contacts the cartilaginous crista parotica and does not reach the otoccipital. The stapes (= columella auris) is present (absent in P. peraticus ). The vomers are separated medially. The prechoanal process is triangular, poorly developed, and laterally oriented. The postchoanal process is narrow and pointed ( Fig. 4 b, d, f). The dentigerous process of the vomer is elongate and narrow, directed posteromedially, extending posteriorly but not reaching the palatine. Pristimantis leptolophus , P. lasalleorum , and P. stictus bear oblique keels on the vomers and lack odontophores and teeth ( Fig. 4 c) (as defined by González-Durán, 2016), whereas P. uranobates , P. peraticus , P. parectatus , P. maculosus , P. scoloblepharus , Pristimantis sp. 3, and Pristimantis sp. 4 bear a small odontophore with a few teeth ( Fig. 4 a), and P. acatallelus and Pristimantis sp. 1 have triangular odontophores with a transverse row of teeth ( Fig. 4 a). The palatine contacts the maxilla and sphenethmoid. The pterygoid is triradiate and the anterior ramus contacts the maxilla, being longer than the posterior and medial rami.

Hyobranchial apparatus. The hyoid plate is cartilaginous, bearing posterolateral processes directed posteriorly and ossified posteromedial processes. The anterolateral processes are absent, except in Pristimantis stictus , where it may be absent or present. The hyales are thin and reach the ventral part of the otic capsule. They bear anterior processes, which are as long as the length of the hyoid plate.

Axial skeleton. The vertebral column has eight procoelous, presacral vertebrae. This condition varies intraspecifically in some species in which the eighth vertebra and sacrum are fused in some specimens (e.g., P. uranobates , ICN 29876; P. stictus , ICN 55717; P. leptolophus , ICN 6745, 25925; P. peraticus , ICN 40777). The vertebrae have complete neural arches and low neural processes. The relative lengths of the transverse processes and sacral diapophyses are: III = Sacrum> IV> II = V = VI = VII = VIII. The sacral diapophyses are slightly expanded distally. The urostyle has a well-developed dorsal ridge that extends along half its length. The phalangeal finger formula is 2-2-3-3, and phalangeal toe formula is 2-2-3-4-3. The proximal phalanx of Toe IV is less than or equal to half the length of Metacarpal IV, which causes the distal phalanx of toe V to reach the base of the penultimate phalanx of Toe IV.

Depressor mandibulae musculature. ( Fig. 5 , Table 2 ). The group of fibers originating from the otic ramus of the squamosal (SQ) has a small flap overlapping the otic ramus (SQ1) ( Fig. 5 d, f). The fibers with origin on the posterior region of the squamosal (SQp), originate on the m. levator posterior longus at the level of the otic ramus of the squamosal (SQp1) ( Fig. 5 d, f)). Additionally, there are no fibers with origin in the dorsal fascia over the scapula (DF2) (except in P. scoloblepharus , Pristimantis sp. 1, and Pristimantis sp. 5, Fig. 5 f).

Figures

FIGURE 2. Second part of the consensus tree showing the phylogenetic relationships of Brachycephaloidea (Pristimantis myersi, P. leptolophus, P. boulengeri, P. devillei species group and unassigned species) as recovered by the 108 most parsimonious trees obtained with direct optimization (length 24341 steps) under equal weights for all transformations. Institutional collection codes follow Sabaj-Pérez (2014). Photos by Marco Rada, John Lynch and Giovany Chaves. Values above nodes are Goodman-Bremer support.

FIGURE 3. Species of P. leptolophus group: A) Pristimantis leptolophus, adult female (ICN 7061; photo: J. D. Lynch). B) P. acatallelus, adult female (ICN 7224; photo: J. D. Lynch). C) P. stictus, adult female (ICN 55702). D) P. maculosus, adult female (ICN 55760; photo: H. Arias). E) P. parectatus, adult female (ICN 55764). F) P. peraticus, adult female (ICN 55767). G) P. scoloblepharus, adult female (ICN 55768). H) P. uranobates, adult female (ICN 55770).

FIGURE 4. Skulls. A, B) Ventral and dorsal view of Pristimantis acatallelus (ICN 28978, female; scale bar: 2 mm and 5 mm, respectively). C, D) Ventral and dorsal view of P. leptolophus (ICN 7033, female; scale bar: 2 mm and 2.5 mm, respectively). E, F) Ventral and dorsal view of P. uranobates (ICN 22738, female; scale bar: 2.5 mm).

FIGURE 5. Musculus depressor mandibulae drawings, scale bars: 2 mm. A) Pristimantis buckleyi (ICN 21843, female). B) P. c urtipes (ICN 22199, female). C) P. devillei (ICN 10734, female). D) P. leptolophus (ICN 41835, female). E) P. myersi (BCQ 827, female). F) P. scoloblepharus (ICN 55769, female).