Gastrotheca monticola

Duellman, William E., Barley, Anthony J. & Venegas, Pablo J., 2014, Cryptic species diversity in marsupial frogs (Anura: Hemiphractidae: Gastrotheca) in the Andes of northern Peru, Zootaxa 3768 (2), pp. 159-177 : 162-164

Redefinition of Gastrotheca monticola

As shown in the phylogenetic analysis, topotypic Gastrotheca monticola are in the same clade as those from Pomacochas, from where a large series is available for the following redefinition; however, there is considerable variation in dorsal coloration ( Fig. 2 ). Also, the analysis shows that specimens from Ecuador are distinct; for these the name Gastrotheca lojana Parker is available. This species is being redefined by Carvajal-Endara et al. (in prep.) and, except for the sequence data, is not included herein.

Diagnosis. A moderately large species—SVL 49.0– 55.7 mm (x = 51.7 ± 2.62, n = 11 males), 48.0– 66.3 mm (x = 58.4 ± 5.11, n = 16 females)—with (1) tibia length 47–55% SVL, about same length as foot; (2) interorbital distance much greater than width of upper eyelid; (3) skin on dorsum shagreen to finely granular, not co-ossified with skull, lacking transverse ridges; (4) supraciliary processes absent; (5) heel lacking calcar or tubercle; (6) tympanic annulus smooth; (7) Finger I slightly shorter than II with discs slightly wider than digits; (8) fingers unwebbed; (9) webbing extending maximally to penultimate subarticular tubercle on Toes IV and V; (10) dorsum green or brown with darker middorsal mark extending to sacrum or paravertebral marks usually connected in occipital region; (11) head markings consisting of dark canthal stripe and pale labial stripe; (12) pale dorsolateral stripe usually absent; (13) flanks and anterior and posterior surfaces of thighs with dark markings; (14) venter cream with dark spots; (15) brood pouch single, dorsal.

Gastrotheca monticola most closely resembles four other species in northern Peru. Gastrotheca aratia lacks black spots on the flanks and anterior and posterior surfaces of the thighs (Table 1); the nuptial excrescences are unpigmented. Additionally, the following phenotypic characters (although partially overlapping) can help distinguishing these species. Specimens of G. aratia usually lack a pale supracloacal stripe (absent in 67% of specimens studied) and are smaller (SVLs of males = 42.8–55.7 mm). Gastrotheca aguaruna differs by being much smaller (SVLs of males = 41.6–46.8 mm) than G. monticola and also by lacking a pale supracloacal stripe and black spots on the flanks and anterior and posterior surfaces of the thighs, and by having a green vocal sac. Gastrotheca dysprosita is like G. monticola in having a bluntly rounded snout in profile but differs from G. monticola by having a green dorsum with a narrow, diffuse, yellow middorsal stripe and green flanks with small yellow spots; furthermore, G. dysprosita has coarsely granular skin on the dorsum and a granular tympanic annulus and lacks a dark canthal stripe and pale labial stripe ( Fig. 2 ). Gastrotheca lateonota is like G. monticola in size and most proportions, but G. lateonota differs from G. monticola by having a truncate snout in profile, smooth skin on the dorsum, and a nearly uniform grayish brown venter. Six other species of Gastrotheca inhabit the Andes in northern Peru. Of these, G. peruana , G. phalarosa , and G. phelloderma have pustular skin on the dorsum. In G. ossilaginis the skin on the head is co-ossified with the underlying bones of the skull. Gastrotheca abdita differs by having an acuminate snout in dorsal view, and G. galeata differs by having a spatulate labium; the latter two species also produce eggs that undergo direct development. Gastrotheca monticola also is similar to G. litonedis Duellman and Hillis and G. lojana Parker in southern Ecuador; both of these species differ from G. monticola by having Fingers I and II equal in length, whereas Finger I is shorter than Finger II in G. monticola . Furthermore, G. litonedis has smooth skin on the dorsum and a uniformly pale grayish brown venter, in contrast to shagreen to granular skin on the dorsum and a cream venter with dark spots in G. monticola .

Distribution and ecology. Gastrotheca monticola , as recognized here, is known from elevations of 1900– 1960 m in the vicinity of the type locality in the valley of the Río Huancabamba, which flows southward into the Río Chamaya, a tributary of the Río Marañón. The species occurs at Ayabaca (2700 m) northwest of the type locality. Its range extends southeastward to several localities at elevations of 2360–3235 m in the northern part of the Cordillera Central in Departamento Amazonas. Individuals have been found in arboreal bromeliads by day; the species thrives in anthropogenic conditions, as was evident of individuals found at night on trees within the village of Pomacochas.

Figures

FIGURE 2. Three previously described species of Gastrotheca from northern Peru. A – C. G. monticola: A. KU 219768, female, 62.1 mm SVL, from 1.8 km N Huancabamba, 1980 m, Piura, Peru; B. KU 219770, female, 60.2 mm SVL, from 4 km N Huancabamba, 1900 m, Piura, Peru; photos by E. R. Wild. C. MHNC 6742, male, 56.5 mm SVL, from Kuelap, 2920 m, Amazonas, Peru; photo by J. C. Chaparro. D. G. dysprosita, KU 212078, male, 60.5 mm SVL, from west slope Abra Barro Negro, 17 km (by road) WSW of Leimebamba, 3440 m, Amazonas, Peru; photo by W. E. Duellman. E and F. G. lateonota: E. KU 181730, female 62.1 mm SVL, KU 181732, female, 50.4 mm SVL, both from El Tambo, 2770 m, Piura, Peru; photos by W. E. Duellman.