Hyloscirtus criptico, Coloma & Carvajal-Endara & Dueñas & Paredes-Recalde & Morales-Mite & Almeida-Reinoso & Tapia & Hutter & Toral & Guayasamin, 2012

Coloma, Luis A., Carvajal-Endara, Sofía, Dueñas, Juan F., Paredes-Recalde, Arturo, Morales-Mite, Manuel, Almeida-Reinoso, Diego, Tapia, Elicio E., Hutter, Carl R., Toral, Eduardo & Guayasamin, Juan M., 2012, 3364, Zootaxa 3364, pp. 1-78 : 20-26

Hyloscirtus criptico sp. nov.

Figs. 1A, 6A, 7A–C

Holotype. CJ 311 , an adult female from a cascading stream on the borderline between Reserva Cotacachi-Cayapas and private land owned by Manuel Quinchiguango , at Recinto San Antonio , Cuellaje, Provincia Imbabura, Ecuador (0º 28' 23.772" N, 78º 34' 12.756" W; 2794 m); obtained on 22 July 2011 by Elicio E. Tapia, Carl R. Hutter, Carlos Quinchiguango, and William Quinchiguango.

Paratypes. CJ 312–313 , adult males with same collection data as holotype ; CJ 309–310 , adult females from Reserva Las Gralarias , Provincia Pichincha, Ecuador (0º 1' 30.66" S, 78º 42' 10.98" W; 2175 m); obtained on 9 and 11 June 2009 respectively, by Carl R. Hutter , Henry Imba, and Timothy Kell ; QCAZ 43516–18 , 43528 , four adult females from the headwaters of a stream at borderline between Reserva Cotacachi-Cayapas and a private land owned by Manuel Quinchiguango , at Recinto San Antonio , Cuellaje, Provincia Imbabura, Ecuador (0º 28' 20.8194" N, 78º 33' 57.6" W; 2760–2885 m); obtained on 24 June 2009 by Luis A. Coloma, Manuel A. Morales- Mite, and Elicio E. Tapia .

Diagnosis. A member of the Hyloscirtus larinopygion group as diagnosed by Faivovich et al. (2005). Hyloscirtus criptico differs from other members of the group by having a unique combination of color patterns and external morphological features (see comparisons below), and a genetic distance from other species of at least 3.7 % in fragments ~ 2.3 kb of aligned mitochondrial DNA sequences. The most similar color patterns are seen in H. larinopygion ( Fig. 1B), H. pacha ( Fig. 1D), H. psarolaimus ( Fig. 1G), H. ptychodactylus ( Fig. 1H), and H. staufferorum ( Fig. 1I), all of which have brown dorsums and black and white bars on the flanks and concealed surfaces of the limbs. The new species differs from H. larinopygion by having small orange flecks and stippling on the dorsum and venter (absent in H. larinopygion ), and a dark brown dorsum (pale brown in H. larinopygion ). Additionally, these are not sister species ( Fig. 3). Hyloscirtus criptico differs from H. ptychodactylus , a species from the slopes of western Ecuador, by having well defined black and white bars on the limbs (white bars absent in H. ptychodactylus ), and by having a dark gray iris color (sky-blue in H. ptychodactylus ). Hyloscirtus criptico differs from H. pacha from the slopes of southeastern Ecuador by having a small calcar on the heel (larger in H. pacha ) and by lacking tubercles along the ventrolateral edge of the arm (prominent in H. pacha ). Hyloscirtus criptico differs from H. psarolaimus from the slopes of eastern Ecuador by having black and white bars on flanks (spots and irregular marks in H. psarolaimus ) and by lacking a mid-dorsum cream line (present in H. psarolaimus ). Finally, the new species differs from H. staufferorum from the slopes of eastern Ecuador by having a boldly, mottled black and cream ventral pattern (venter uniform gray or nearly uniform in H. staufferorum ).

Description of holotype. SVL 71.4 mm. Body and limbs robust. Snout nearly truncate in dorsal and lateral view. Head about as broad as long. Head widest at posterior level of mandible (22.7 mm), representing 31.8% of SVL. Canthus rostralis rounded. Loreal region slightly concave. Lips rounded, not flared. Dorsal surface of internarial region nearly flat. Nostrils barely protuberant, directed anterolaterally, slightly posterior to anterior margin of lower jaw. Top of head slightly concave. Tympanum vertically ovoid, tympanic annulus distinct. Supratympanic fold thick, curved, not covering posterodorsal edge of tympanum, extending from eye to posterior end of mandible and to shoulder.

Forearms robust compared to upper arms. Axillary membrane absent. Ulnar tubercles absent. Fingers broad. Disks round, expanded, wider than finger. Relative lengths of fingers 1<2<4<3. Lateral fringes absent. Palmar surface ( Fig. 7B) with deep folds and low raised, oval, supernumerary tubercles. Subarticular tubercles single, large, thick, rounded, or oval. Thenar tubercle thick, elliptical. Palmar tubercle round. Prepollex absent. Fingers webbed basally, manus webbing formula: I 3–3 II 2–3 III 2 1/2–2 1/2 IV. Hind limbs robust. Tibia length 47.6% of SVL. Small conical heel tubercle present. Inner tarsal fold absent. Foot length 47.3% of SVL. Inner metatarsal tubercle large, oval ( Fig. 7C). Outer metatarsal tubercle absent. Subarticular tubercles round or oval. Supernumerary tubercles absent. Toe discs wider than fingers. Relative lengths of toes I<2<3<5<4. Foot webbing formula: I 2–3 II 2–2 1/2 III 2–2 1/2 IV 2–1 1/2 V.

Skin on throat, chest and belly smooth, the latter bearing a transversal fold at gular level. Pelvic patch areolate. Transverse supracloacal flap long. Margins of vent with numerous small folds and two large lateral swollen glandular areas at proximal posterior thighs. Cloacal opening directed posteriorly. Dentigerous processes of vomers long, transverse, separated medially, behind level of large, ovoid choana, bearing 28 teeth evident in the buccal mucosa. Tongue broad, cordiform, shallowly notched posteriorly, fully attached to mouth floor.

Color in preservative (~70% ethanol). Dorsum of head, body, forearms, shanks, and outer margin of feet grayish-brown densely stippled with minute, cream flecks. Anterior and posterior surfaces of thighs barred with four or five white and brown bars crossed by a transverse dark brown stripe. Ventral surfaces of upper arms with dark brown marks on a cream background and shanks barred with cream and brown. Dorsal surfaces of Fingers I–II and toes I–III bearing white and dark brown marks, fingers III–IV and toes IV–V mostly dark brown. Glandular area lateral to vent having brown with cream stippling. Flanks bearing white and bold brown markings. Throat, chest, abdomen with boldly, mottled dark brown and cream, larger cream marks toward the distal longitudinal axis. Pelvic patch brown. Palmar and plantar surfaces gray. Tympanum brown with cream stippling similar to adjacent areas.

Color in life. ( Fig. 6A). Same as above except in that dorsum marks and blotches are bright orange varying to pale orange and yellow-cream. Blotches on hidden surfaces of thighs are creamy-white. Ventral surfaces are black with yellow-cream marbling. Tips of dorsal surfaces of fingers and toes are pale creamy-orange. Ventral pads of digital discs on fingers and toes are gray. Iris is dark gray.

Measurements of holotype (mm). SVL 71.4, TIBL 34, FEL 30.3, FOL 33.8, RDUL 20.1, HANDL 24.5, THBL 15.9, HLSQ 23, HDW 22.7, ITN 4.5, EYNO 3.9, TYD 3.4, DFW 4.6, DTW 4, SW 13.7.

Variation. Dorsum and ventral color pattern variation of paratypes is depicted on Figure 8. Morphometric variation is indicated in Table 7. Dentigerous processes of vomers are abutted medially, and vomerine teeth number varies from 16 to 30 as follows: 26 teeth ( CJ 309 ) , 26 ( CJ 310 ) , 16 ( CJ 313 ) , 22 ( CJ 312 ) , 25 ( QCAZ 43516 ) , 19

(QCAZ 43517), 20 (QCAZ 43518), 30 (QCAZ 43528). Dorsum color varies from nearly uniform dark brown in CJ 365 to heavily stippling on a dark brown background in CJ 250 and 251. Dorsal bars on thighs and ventral bars on shanks vary between 4 or 5. Sexual dimorphism is apparent in males having a venter more uniform (dark brown or gray) than females, which have more cream marks. Besides, males have vocal slits.

Tadpoles. Tadpoles of this species are unknown.

Distribution, natural history, and conservation status. Hyloscirtus criptico is known from three localities at elevations of 2175–2794 m, in cascading streams in Montane Cloud Forest ( Valencia et al. 1999) on the western versant of Cordillera Occidental de los Andes from Carchi, Imbabura, and Pichincha provinces ( Fig. 9). The area of distribution is approximately 1570 km 2. At the known localities annual mean precipitation is 1516, 1597, and 1653 mm, and the annual mean temperatures are 14.3, 16.0, and 13.4 ºC (estimated from the WorldClim data set; Hijmans et al. 2005). Distribution at “Hercules Creek” at Reserva Las Gralarias is indicated in Figure 10. Average daily rainfall from 17 January 2011 to 1 July 2011 at Las Gralarias is given in Hutter and Guayasamin (2012).

Toral et al. (2002) provide a detailed description of the type locality and a record of three males of this species (cited as Hyla larinopygion ). Quiguango (1997) provided a map, a description of biotic and abiotic features at San Venancio, El Rosario (ca. Cuellaje), Cordillera de Toisán, and abundance data of Hylocirtus criptico (cited as Hyla larinopygion ). At the mentioned locality, H. criptico is an uncommon species, and was only found in the rainy season in January 1994.

At San Antonio (ca. Cuellaje) (type locality) ( Fig. 11B–D), Hyloscirtus criptico was found at the upper part of a cascade that is about 10 m wide and 8 m high. The headwater springs are about 20 m higher than the collecting site and about 80 m from the nearest divide. Mosses and epiphytes were abundant on the vegetation along the stream. Adults were collected during night at the stream, except a female (QCAZ 43528) that was collected on the ground in a primary forest of the mountain crest. CJ 311 (holotype) and CJ 312–313 (paratypes) were collected among branches of a fallen tree and shrubs, which were decomposing over the streambed, which had small water ponds. QCAZ 43516–17 were collected on branchs 1.5–4 m above ground over the streambed; there was no rain, but clouds were inside the forest. QCAZ 43518 was on a stone in the streambed. At this locality, H. criptico was found in microsympatry with H. princecharlesi , and in one case within 10 m of each other.

The habitat at Reserva Las Gralarias is undisturbed. A trail to the stream was recently established, but no pastures or agricultural activity occurs upstream. The stream is 2–4 m across. Water temperatures were: 14.1, 13.9–14.3 ºC (n = 4) and pH values were 7.6, 7.5–7.7 (n = 4). Specimens were found during the night within 20 m of each other at an air temperature of 13 ºC. There was a light rain, no moonlight, and no clouds. CJ 309 was found at 3:49 am, perched on a large aroid leaf, 4 m directly above the stream, and about 0.5 meters above ground. CJ 310 was found at 2:35 am, perched on a horizontal branch, facing the stream, 2.5 m vertically above stream and 1 m horizontally away from water, on a sloping bank, and 0.5 m above the ground. At this locality, Hyloscirtus criptico occurs microsympatrically with five stream breeding glassfrogs ( Centrolene ballux Duellman and Burrowes 1989 , C. heloderma [ Duellman 1981], Nymphargus grandisonae [ Cochran and Goin 1970], N. griffithsi [ Goin 1961], and N. lasgralarias Hutter and Guayasamin 2012 ).

Hyloscirtus criptico is considered as Endangered (A3ce IUCN criteria) due to a suspected population size reduction of ≥ 50% suspected to be met within the next 10 years, where the reduction or its causes may not have ceased. The area of extent of ocurrence (1570 km 2) is relatively small, and the localities of its small known areas of occupancy are being modified by human activities and is being severely affected by growing habitat destruction. Threats are logging, burning, unregulated use of land for agriculture, cattle raising, pesticide use, and invasive trout in the regional streams. Besides, it is likely that climate change and emerging pathogens are affecting its populations as has been documented for numerous other Andean frogs (Pounds et al. 2010). Rapid and integrative conservation measures are urgently needed, among which the protection and restoration of its habitat are a priority, as well as the establishment of an ex-situ assurance colony.

Etymology. The specific name criptico is used as a noun in apposition. Criptico is a Spanish word that means hidden and it is used in reference to specimens of this species, which were initially confused with a sympatric species Hyloscirtus larinopygion . Its name calls attention to cryptic species, which are being revealed frequently in the recent taxonomic literature, especially with the advent of molecular analyses and integrative taxonomy (e.g., Elmer and Cannatella 2008, Páez-Vacas et al. 2010, Funk et al. 2011, Hutter and Guayasamin 2012).

Comments. Most previous records of Hyloscirtus larinopygion from Ecuador in the provinces of Carchi and Imbabura are erroneous, and belong to H. criptico as described herein. Duellman and Coloma (1993) assigned the name Hyla larinopygion to five adult males (QCAZ 4167–71) and eight tadpoles (QCAZ 4172) from 22 Km E of Maldonado, Provincia Carchi. Their assignment was done on the basis of size and overall phenetic similarity of adults when compared to specimens from Municipio Sonsón in Departamento Antioquia, Colombia. Nonetheless, they noted differences in dorsal coloration. All these adult males (QCAZ 4167–71) are herein referred to Hyloscirtus criptico . A series of tadpoles (QCAZ 4172) may be either H. criptico or H. larinopygion , which cooccur at nearby sites. Quiguango (1997) and Toral (2002) also assigned the name Hyla larinopygion to specimens from San Venancio, Cuellaje, Provincia de Imbabura; these specimens also represent H. criptico . Additional records of H. larinopygion from Provincia Imbabura provided by Bolívar et al. (2004) are unconfirmed because no voucher specimens were provided.

Yánez-Muñoz and Meza-Ramos (2006) published a color photo of Hysloscirtus larinopygion from Morán, Provincia de Carchi, Ecuador. Herein we provide records (based on voucher specimens) of adults of H. larinopygion that were collected in Provincia de Carchi. They are: QCAZ 29211–12 from 24 Km E of Maldonado (0º 49' 23.376" N, 78º 1' 31.4" W; 2664 m; on the Tulcán-Maldonado road), Provincia Carchi collected on 4–5 June 2004 by Néstor Acosta-Buenaño, Ítalo G. Tapia, and Catherine Graham ; QCAZ 41826 from Comunidad de Morán (0º 44' 48.1194" N, 78º 6' 14.004" W; 2452m), Provincia Carchi, collected on 23 September 2008 by Ítalo G. Tapia, Juan F. Dueñas, and Carlos Castro ; QCAZ 38418 (a series of tadpoles) from Cerro Centella, cascada Centella, 2709 m, on the road Tulcán-Maldonado ), Provincia Carchi, collected on 17 September 2008 by Juan F. Dueñas and Ítalo G. Tapia. Tadpoles were raised under lab conditions and their identification as H. larinopygion was confirmed (see description provided under Tadpoles and ontogeny) .