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| Gastrotheca flavodactyla Echevarría, Paluh, García-Ayachi, Venegas, Catenazzi, Pradel & Castroviejo-Fisher, 2022 Photographs by R. Pradel. |
Abstract
We describe two new species of Gastrotheca from the humid montane forests and grasslands of La Libertad and Amazonas departments, respectively, in the northern portion of the central Peruvian Andes. Our phylogenetic analysis recovered the new species as part of the Gastrotheca marsupiata species group and closely related to G. gemma, G. oresbios, G. psychrophila, G. spectabilis, G. stictopleura, and one undescribed species. The new species from La Libertad department can be differentiated from the aforementioned congeners by being of moderately small size (SVL = 33.3–41.9 mm, N = 3), having an acutely rounded snout in dorsal view, a rounded snout in lateral view, smooth skin on the dorsum with low granules, and smooth tympanic annulus and supratympanic fold. The new species from Amazonas department (SVL = 33.5–43.9 mm, N = 2) differs from other Gastrotheca species by having the dorsum covered with large and closely packed rounded pustules, two prominent paravertebral longitudinal pustular ridges, and a distinctly thick and elevated supratympanic fold extending from the top edge of the tympanum to the flank and being continuous or fused with the dorsolateral row of elongated pustules. In addition to external morphological characters, we include detailed descriptions and illustrations of the skeleton of the holotypes based on 3D models obtained from CT-scans.
Key words. Amphibia, CT-scan, Gastrotheca, osteology, phylogeny, taxonomy.
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| Gastrotheca flavodactyla sp. n. in life. Dorsolateral (A) and ventral (B) views of the male holotype (CORBIDI 18840), 40.8 mm SVL. Lateral (C) and ventral (D) views of a male paratype (CORBIDI 18841), 33.3 mm SVL. Dorsolateral (E) views of a male paratype (CORBIDI 20470) and of a juvenile paratype (CORBIDI 18842). Photographs by R. Pradel. |
Gastrotheca flavodactyla sp. n.
Diagnosis. Assigned to the genus Gastrotheca due to its
phylogenetic placement in our results. The two unambiguous phenotypic synapomorphies proposed for the genus
(Castroviejo-Fisher et al. 2015) – the presence of an enclosed pouch with a posterior opening in adult females,
and two fused pairs of bell-shaped gills derived from
Branchial arches I and II in embryos – correspond to semaphoronts not available for this study. A moderately small
species (SVL between 33.3 and 41.9 mm in adult males)
with: (1) snout acutely rounded and rounded in dorsal and
lateral views, respectively; (2) canthus rostralis slightly
concave; (3) loreal region concave; (4) tibia length 53–55%
of SVL, slightly longer than foot; (5) interorbital distance
almost twice the width of the upper eyelid; (6) skin on dorsum smooth with low granules, skull not co-ossified, but
adherent with it above, lacking transverse ridges; (7) supraciliary processes absent; (8) tubercles on heel present,
low; (9) tympanic annulus smooth; (10) nuptial pad present, oval; (11) vocal sac not evident externally; (12) Finger I slightly shorter than Finger II, discs wider than digits;
(13) webbing between fingers basal; (14) foot webbing basal, extending to penultimate subarticular tubercle on the
postaxial side of Toes II (2) and III (2+) and on the preaxial
side of Toe V (2+); (15) dorsum green or brown with spots,
blotches or wide dorsolateral stripes, dorsal surface of finger and toe pads yellow; (16) dark brown or black blotches (melanophores) forming a broad and discontinuous vertebral stripe extending from interorbital region to above the
cloaca, more evident in preserved specimens; (17) dorsolateral stripe absent; (18) flanks green with or without black
or brown blotches, or golden spots; (19) gular region yellow
with dense black reticulation or uniformly black; venter
yellow with a diffuse light green spot and melanophores in
the middle or greyish cream; ventral surface of thighs black
or dark grey; palms and soles black or dark grey due to
abundant melanophores, which extend to all ventral surfaces of fingers and toes but are more abundant on Fingers
III and IV, and Toes III and IV; (20) iris copper-red or yellow with black reticulation. Females unknown, for which
reason the brood pouch opening and reproduction mode,
two characters often used in Gastrotheca species diagnosis,
are unknown as well.
Distribution and natural history. Gastrotheca flavodactyla
is known so far only from Cruz Grande and Laguna Secseragra, at 3298 and 3336 m a.s.l. respectively, in La Libertad
department. These localities are less than 1 km apart and lie
in the humid montane forest of the headwaters of the Abiseo River, Cordillera Central Páramo ecoregion (Olson
et al. 2001), in the northern portion of the Central Andes
(Fig. 7). All specimens were found inactive under stones
along the edge of a road at the transition between elfin forest and grassland between 14:20 and 17:00 hours, where
they seemed to be resting.
Etymology. The specific epithet combines the Latin word
flavo, an adjective meaning “yellow”, and the Greek word
dáchtyla, a noun meaning “fingers”. This specific name is
used in apposition and refers to the yellow finger and toe
pads of the new species in life.
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| Skeleton of Gastrotheca trachyplevra sp. n. (CORBIDI 16614) with a single late stage froglet inside the pouch as visualized via Micro-CT scanning in dorsal view (A). (B) Left manus and pes in ventral views, (C) pectoral girdle in ventral view, and (D) ilium in right lateral view. Scale bar = 1 mm. |
Gastrotheca trachyplevra sp. n.
Diagnosis. Assigned to the genus Gastrotheca by the presence of a closed brood pouch on the dorsum of the only
known adult female, and its phylogenetic placement in the
genus. A moderately small species (43.9 mm SVL in one
female, 33.5 mm SVL in one male) with: (1) snout rounded
and inclined anteroventrally in dorsal and lateral views, respectively; (2) canthus rostralis concave; (3) loreal region
concave; (4) tibia length 40−41% of SVL, slightly shorter
than foot; (5) interorbital distance less than twice the width
of upper eyelid; (6) dorsum covered with large and closely packed rounded pustules and two prominent paravertebral longitudinal pustular ridges, skin not co-ossified with
skull; (7) supraciliary processes absent; (8) small rounded
tubercles on heel present; (9) tympanic annulus smooth;
(10) nuptial pad present, oval; (11) vocal sac not evident
externally; (12) Finger I longer than Finger II, discs barely wider than digits; (13) fingers unwebbed, basal webbing
only between Fingers II and III; (14) toe webbing basal, extending to penultimate subarticular tubercle on preaxial
(2+) and postaxial (2−2-
) sides of Toe II, on postaxial side
of Toe III (2+), and on preaxial side of Toe V (2+); (15) female dorsal coloration light brown with black and dark
brown blotches; male dorsal coloration green with brown
blotches; (16) male and female’s head markings consisting
of small brown blotches; (17) dorsolateral stripe absent;
(18) flanks with the same coloration and pattern as the dorsum; (19) gular region dull white in female and golden in
male, venter dull white with a pink or light orange hue over
the posterior edge in female and male, respectively, ventral
surface of thighs red, brighter in the female, and greyish
towards the knee, palms and soles grey with reddish and
yellowish hues in female and male, respectively; (20) iris
dark brown with a few golden specks and a golden pupillary ring; (21) brood pouch single, dorsal, with a V-shaped
opening; (22) direct development of embryos into froglets.
Etymology. The specific epithet results from combining the
Greek words trachýs, an adjective meaning “rugose”, and
plevrá, a noun meaning “flank”. This specific name is used
in apposition and refers to a distinctive feature of the new
species, the rugose flanks full of pustules.
Lourdes Y. Echevarría, Daniel J. Paluh, Luis A. García-Ayachi, Pablo J. Venegas, Alessandro Catenazzi, Renzo Pradel and Santiago Castroviejo-Fisher. 2022. Two New Species of Marsupial Frogs (Anura: Hemiphractidae) from the Central Andes of northern Peru. SALAMANDRA. 58(1); 1–23.