Pristimantis sira, Chávez & García-Ayachi & Catenazzi, 2021

Chavez, German, Garcia-Ayachi, Luis A. & Catenazzi, Alessandro, 2021, Beauty is in the eye of the beholder: Cruciform eye reveals new species of direct-developing frog (Strabomantidae, Pristimantis) in the Amazonian Andes, Evolutionary Systematics 5 (1), pp. 81-92 : 81

publication ID	https://dx.doi.org/10.3897/evolsyst.5.63674
publication LSID	lsid:zoobank.org:pub:117AA0B4-99A2-4F4F-85A9-B9FAE8E47BB1
persistent identifier	https://treatment.plazi.org/id/6579CBED-1CF0-4D59-8B37-FDB405EFB352
taxon LSID	lsid:zoobank.org:act:6579CBED-1CF0-4D59-8B37-FDB405EFB352
treatment provided by	Evolutionary Systematics by Pensoft
scientific name	Pristimantis sira
status	sp. nov.

Treatment

Pristimantis sira sp. nov. Figs 1 View Figure 1 , 2 View Figure 2 , 3 View Figure 3 , 4D View Figure 4

Holotype.

PERU • 1 ♀, adult; Huánuco department, Huánuco province, Campamento Peligroso, El Sira Communal reserve; 9°25'34.2"S, 74°44'6.6"W; 1520 m a.s.l.; 24 March 2014; G. Chávez and Jose Malqui; CORBIDI 14430.

Paratopotypes.

PERU • 1 ♂, 2 ♀, adults and a juvenile; same data as for holotype; 01 December 2013; G. Chávez; CORBIDI 14433 (Figure 3C, D View Figure 3 ), 14429 (Figure 3E, F View Figure 3 ), 14432, 13952.

Paratypes.

PERU • 1 ♀, adult and a juvenile; Huánuco department, Pachitea province, Campamento La Cumbre; 9°25'27.0"S, 74°42'47.0"W; 2145 m a.s.l.; 30 November 2013; G. Chávez; CORBIDI 13933, 13944.

Diagnosis.

The new species is diagnosed by the following combination of characters: (1) skin on dorsum finely shagreen with a few scattered subconical tubercles, that on venter areolate, W-shaped scapular fold present, discoidal fold absent, dorsolateral folds absent; (2) tympanic membrane and tympanic annulus absent, supratympanic fold absent; (3) snout acutely rounded from dorsal view, moderate in length and rounded from lateral view, canthus rostralis weakly concave in dorsal view, angular in lateral view, loreal region concave, rostral papilla or keel absent; (4) upper eyelid bearing two or three sub conical small tubercles, narrower than IOD, cranial crests absent; (5) dentigerous process of vomers absent; (6) males with vocal sacs and vocal slits, nuptial excrescences absent; (7) heels lacking tubercles; (8) finger I shorter than finger II, tips of digits expanded, bearing circumferential grooves, discs about 1.5 times wider than digits in fingers I, II and III, finger IV bearing a rounded disc about twice as wide as its digit; (9) fingers with narrow lateral fringes; (10) antebrachial tubercle absent; (11) ulnar and tarsal tubercles absent (12) inner metatarsal tubercle oval twice as long as round outer metatarsal tubercle, low supernumerary plantar tubercles at the base of toes II, III, IV and V; (13) toes without lateral fringes, webbing absent, toe V longer than toe III; (14) in life, dorsum yellowish-brown, dark brown or olive brown with dark transversal bands; interorbital bar dark brown; canthus rostralis paler than loreal region and dark bordered; dark labial bars present; throat, chest, and belly dark brown or dark grey with scattered white flecks; groins, posterior surfaces of thighs, and shanks dark brown; iris copper yellow with a vertical black line and dark reticulations, black pupil surrounded by a copper orange ring; (15) SVL 12.9-14.7 mm in males; 19.0-20.4 mm in females.

Comparisons.

The combination of having a vertical line crossing the iris (which forms a cruciform mark) and lacking tympanic annulus and membrane distinguishes Pristimantis sira sp. nov. from most congeners except P. altamazonicus Barbour & Dunn, 1921, P. antisuyu , P. ashaninka Lehr Moravec, 2017, P. cruciocularis and P. erythroinguinis . However, P. sira is easily differentiable from all of them by (condition for the other species in parenthesis): having 2-3 small sub conical tubercles on upper eyelid (vs a single conical tubercle in P. altamazonicus , 4-6 small tubercles in P. antisuyu , enlarged conical tubercles in P. ashaninka , 2-5 small tubercles in P. cruciocularis , and 4-6 large and small tubercles in P. erythroinguinis ), groins and posterior surface of thighs dark without spots or flecks (vs bearing red or yellow blotches in P. cruciocularis , yellow blotches in P. antisuyu , red blotches in P. erythroinguinis , see Figure 4 View Figure 4 ), vocal slits in males (vs absent in P. altamazonicus , P. antisuyu , P. cruciocularis and P. erythroinguinis ), vomerine teeth absent (vs present in P. altamazonicus , P. antisuyu , P. ashaninka , P. cruciocularis and P. erythroinguinis ), and heels lacking tubercles (vs present P. altamazonicus , P. antisuyu , P. ashaninka , P. cruciocularis and P. erythroinguinis ). Additionally, P. sira is genetically related to P. croceoinguinis Lynch, 1968, and P. boucephalus Lehr, Moravec, Cusi, Gvozdik, 2017. Nevertheless, P. sira is distinct in bearing dark groins without blotches (vs yellow groin in P. croceoinguinis and P. boucephalus ), skin on dorsum shagreen (vs tuberculate in P. croceoinguinis and smooth in P. boucephalus ), upper eyelid having two or three sub conical tubercles (vs tubercles absent in P. creoceoinguinis ), lacking dentigerous process of vomers (vs present in P. croceoinguinis ), and heels lacking tubercles (vs conical tubercle on heels present in P. boucephalus ).

Description of the holotype.

An adult female (CORBIDI 14430; Figure 2A-E View Figure 2 , 3A, B View Figure 3 ) with a SVL of 19.6 mm, head as wide as long (Fig. 2A, B View Figure 2 ); snout acutely rounded in dorsal view and rounded in lateral view, short (eye-nostril distance 9.8% of SVL); canthus rostralis distinct in lateral view; loreal region concave; nostrils protuberant, directed anteriorly; interorbital area flat, slightly broader than upper eyelid (upper eyelid width 89% of interorbital distance); cranial crests absent; upper eyelid bearing two small subconical tubercles; tympanic membrane absent; tympanic annulus absent (Fig. 2E View Figure 2 ); postrictal tubercles absent. Choanae small, rounded, not concealed by palatal shelf of maxillary; tongue longer than wide and granular, dentigerous processes of vomers absent. Skin texture on dorsum and flanks finely shagreen; dorsolateral folds absent; venter areolate; thoracic fold present, discoidal fold absent, cloacal sheath absent. Forearm slender; ulnar tubercles absent, ulnar fold absent; radio-ulnar length 22% of SVL; fingers with narrow lateral fringes; relative lengths of fingers I ≤ II <IV <III; palmar tubercle bilobed, thenar tubercle oval (Fig. 2C View Figure 2 ); subarticular tubercles round, prominent; supernumerary palmar tubercles present at the base of all fingers; disc cover finger I barely expanded, those of fingers III and IV extensively expanded (Fig. 2C View Figure 2 ), outer discs of fingers as wide as those of toes; discs covered with elliptical ventral pads defined by circummarginal grooves. Hind limbs slender; tibia length 48% of SVL; foot length 94% of tibia length; tarsal fold absent, tarsal tubercles absent; heel lacking tubercles; toes without lateral fringes; subarticular tubercles round, prominent; inner metatarsal tubercle oval, about 2.4 times the size of subconical outer tubercle (Fig. 2D View Figure 2 ); supernumerary plantar tubercles low at the base of all toes; discs covers slightly expanded; toes with defined pads; discs pads nearly elliptical; relative length of toes I <II <III <V <IV; tip of toe V reaching proximal border of distal subarticular tubercle IV; tip of toe II reaching proximal border of distal subarticular tubercle of Toe III (Fig. 2D View Figure 2 ).

Measurements (in mm) and proportions of the holotype: SVL = 19.6; HL = 6.7; HW = 7.2; ED = 2.7; E-N = 1.9; IOD = 1.8; EW = 1.6; IND = 1.7; TL = 9.5; FL = 9.0; HL/SVL = 0.3; HW/SVL = 0.3; EW/IOD = 0.8; E-N/ED = 0.7; TL/SVL = 0.4; FL/SVL = 0.4; FL/TL = 0.9.

Coloration in life (Fig. 3A, B View Figure 3 ). Dorsum, flanks, and dorsal surface of limbs are yellowish-brown with dark brown transversal bands and reddish-orange tubercles; dorsal surface of head bearing a dark brown interorbital bar; canthus rostralis yellowish-brown, loreal region dark brown, labial bars dark brown, and white minute flecks present on the upper labial region. Throat, chest, belly, ventral surface of limbs, hands and feet dark brown with white flecks; groins, posterior surface of thighs, and posterior surface of shanks dark brown. Anterior surface of thighs is dark brown. Iris copper yellow with a vertical black line and dark reticulations, black pupil surrounded by a copper orange ring.

Coloration in preservative (Fig. 2A, B View Figure 2 ). Despite the skin on dorsum suffering damage, the coloration is similar to coloration in life, except that dark brown coloration turned yellowish-brown. The venter, limbs and ventral surfaces of hands and feet are yellowish-brown with creamy-white flecks, discs on hands and feet dark grey; iris gray.

Intraspecific variation.

Dorsal coloration from yellowish brown to dark brown in juvenile CORBIDI 13952 (Figure 3G, H View Figure 3 ) and olive brown in female CORBIDI 14429 (Figure 3E, F View Figure 3 ). Moreover, CORBIDI 13952 has a pattern consisting of a middorsal creamy white line going from the tip of the nose to the cloaca, a pale interorbital bar, and a thin creamy white mid-throat line going from the chin to the distal edge of the throat. Furthermore, male CORBIDI 14433 (Figure 3C, D View Figure 3 ) has a yellowish-brown throat, a greyish-white belly, and yellowish-brown coloration on the ventral and posterior surface of thighs. Table 1 View Table 1 reports variation in measurements and proportions.

Etymology.

The species epithet " Pristimantis sira " is a noun in apposition, referencing El Sira Communal Reserve, a protected area established in 2001, containing the type locality of the new species. El Sira also protects one of the last large extensions of primary mountain forests in Central Peru.

Distribution, natural history and threats.

We observed Pristimantis sira sp. nov. on leaves, at 1-1.7 m height, in the forests of the eastern slopes of the mountains of El Sira Communal Reserve, between 1500-2200 m a.s.l (Figure 5 View Figure 5 ). The habitat at 1500 m a.s.l. is a montane forest, with riparian vegetation consisting mainly of bushes, tree ferns and trees canopy ~20 m tall (Figure 6A, C View Figure 6 ). Climbers are also present (lianas) as well as low epiphytes, ferns, mushrooms, and lichens on the ground. Low trees (no more than 8-10 m tall) dominate the forest at 2000 m a.s.l. (Figure 6B View Figure 6 ), where there are bushes and large patches of Chusquea spp., in addition to small ferns, epiphytes and mushroom colonies. We found P. sira at night, at the beginning and the end of the rainy season, but could not hear any male calling. Sympatric species were Pristimantis cruciocularis , P. iiap Padial, Gagliardi-Urrutia, Chaparro & Gutiérrez, 2016, P. cf. mendax Duellman, 1978, and Rhinella nesiotes Duellman & Toft, 1979. We have noticed illegal mining activity in the foothills of El Sira Communal Reserve. Mining activities could affect the mountain slopes because miners establish camps and build trails to move their equipment across the watersheds, creating disturbance to stream and riverine environments that could cause further deforestation in the type locality of P. sira .