Atelopus petersi, Coloma, Luis A., Lötters, Stefan, Duellman, William E. & Miranda-Leiva, Alfonso, 2007

Coloma, Luis A., Lötters, Stefan, Duellman, William E. & Miranda-Leiva, Alfonso, 2007, A taxonomic revision of Atelopus pachydermus, and description of two new (extinct?) species of Atelopus from Ecuador (Anura: Bufonidae), Zootaxa 1557, pp. 1-32 : 11-16

Atelopus petersi sp. nov.

Atelopus pachydermus (non Schmidt): Rivero, 1963:107, 1968:23; Harding, 1983:58; Peters, 1973:34; Frost, 1985:31; Lötters, 1996:39; Coloma and Ron, 2001:38, La Marca et al. 2005:195.

Atelopus sp.: Almendáriz and Cisneros, 2005:155.

Holotype. QCAZ 300, from Ecuador: Provincia Napo: Cantón Quijos: near Oyacachi, (00°12'36" S, 78°42'00" W; approximately 3200 m above seal level), obtained on 3 April 1988 by Stella de la Torre-Salvador.

Paratypes. QCAZ 301 and 302 (cleared and double stained preparation), same data as holotype, collected by Manuel Pallares; QCAZ 298 (cleared and double stained preparation), 299, and 3154, same data as holotype, obtained on 30 March 1988 by Felipe Campos-Yánez and Stella de la Torre-Salvador; QCAZ 4555 from Río Oyacachi, 2 Km east from Oyacachi, obtained on 19 August 1993 by Elicio Tapia; QCAZ 7678 from 1 km E of Oyacachi, 3150 m above sea level, obtained by Felipe Campos-Yánez, Jorge Washington Izquierdo, and Diego Almeida-Reinoso, on 8 November 1996; USNM 193494, 193523, 193526–31 from Oyacachi, obtained by A. Proaño (no date); USNM 193521 from 2 Km E of Chalpi, 2755 m above sea level obtained on 7 July 1962 by James A. Peters; MHNG 2246.93–94 from 11 km (by road) east-southeast of Papallacta (00°03'S, 78°08' W), 2660 m above sea level, obtained on November 1985 by Giovanni Onore and Luis A. Coloma; KU 117874–79 from 3 Km east of Papallacta, 2900 m above sea level, obtained on 7 March 1968 by John D. Lynch, KU 142950 from 7.8 Km west-north-west of Cuyuja, KU 142951–2 from 5.7 Km east of Papallacta, KU 142953–54 from Río Papallacta, 4.6 Km east of Papallacta, 2890 m above sea level, obtained on 28 October 1971 by William E. Duellman; USNM 193496–502, 193506–18 from 0.5 km E of Papallacta, 3150 m above sea level, obtained on 5 July 1962 by James A. Peters and P. Spoecker; USNM 193503, from 1 km W of Papallacta, 3150 m above sea level, obtained on 6 July 1962 by James A. Peters et al.

Referred specimens. QCAZ 3870 and 3871 from Provincia Chimborazo: Lagunas de Atillo, obtained on 3 November 1990 by Anne Claire Desfossey; EPN 3307 from Laguna Cuyug (Cantón Guamote), 3318 m above sea level, 02° 10' 42'' S, 78° 30' 30'' W, obtained on 19 September 1986 by Ana Almendáriz.

Diagnosis. (1) A moderate-sized species with mean SVL in adult males 38.9 mm (35.2–42.1 mm, n = 16) and in adult females 46.0mm (43.3–50.2, n = 11); (2) hind limbs short, mean tibia length/SVL 0.370 (0.327– 0.420, n = 26); (3) phalangeal formula of hand 2-2-3-3, basal webbing absent; (4) foot webbing formula I(0+)—(0+–1) II (0+–1)—(0+–1) III (0+–1)—(2) IV (2-–2)—(0+–1) V; (5) snout acuminate, slightly protruding beyond lower jaw; (6) tympanic membrane, tympanic annulus and stapes absent; (7) dorsal surfaces varying from smooth to warty; (8) white spiculae (cream in preservative) on forearms, flanks, and dorsal surfaces of thighs; (9) vertebral neural processes inconspicuous; (10) dorsum with yellow orange pattern to almost entirely black, flanks white (cream to cream and black in preservative); (11) venter yellow with or without black marks, or uniform orange to reddish orange (cream to pale yellow, occasionally with black marks in preservative); (12) gular region without warts, spiculae or coni.

Atelopus petersi is distinguished from all other species of Atelopus (except an undescribed species from southern Ecuador, Provincia Loja) by its white digital pads that contrast with adjacent black phalanges. Atelopus petersi is most similar to A. bomolochos , A. pachydermus , and Atelopus sp. (Provincia Loja) by having digital pads contrasting in color to adjacent phalanges. It differs from A. bomolochos and Atelopus sp. by having few spiculae on flanks (i.e., almost lacking); numerous spiculae present on flanks of A. bomolochos ( Figs. 3 B–D) and A. sp. It further differs from A. bomolochos by having white marks on flanks (absent in A. bomolochos ). It differs from A. pachydermus by significantly smaller size (mean female SVL of A. petersi = 46.0 vs. 55.9–61.6 in A. pachydermus ) and by lacking brown colors in life.

Description of holotype. ( Figs. 5 A–C). Head slightly longer than wide; head length and head width less than one third SVL (HLSQ/SVL = 0. 284; HDWD/SVL = 0.262; snout truncate in dorsal view; barely protruding beyond anterior margin of jaw; tip of snout lacking swollen gland; nostrils slightly protuberant, directed laterally, situated behind level of apex of lower jaw; canthus rostralis distinct, slightly swollen from eye to nostril; loreal region concave, lips not flared, interorbital and occipital regions flat, smooth, eyelid flared without distinct tubercles; postorbital crest glandular; temporal areas warty; tympanic membrane and tympanic annulus absent; choanae small, rounded, widely separated; tongue more than twice as long as wide, slightly broader anteriorly, its posterior half not attached to mouth’s floor; ostia pharyngea absent.

Forearm relatively short (RDUL/SVL = 0.297); palmar tubercle round, supernumerary palmar tubercles absent; thenar and subarticular tubercles distinct; digital tips with round pads; thumb relatively long (THBL/ HAND = 0.628) having two phalanges; webbing on hands absent, fingers having lateral fringes; relative length of fingers II<III<V<IV.

Tibia relatively short (tibia/SVL = 0.360); no fold on distal half of inner edge of tarsus; outer metatarsal tubercle round, slightly raised, about two thirds length of oval inner metatarsal tubercle; supernumerary plantar tubercles absent; subarticular tubercles conspicuous, digital pads distinct; toes webbing formula I(0+)—(0+– 1) II (0+–1)—(0+–1) III (0+–1)—(2) IV (2-–2)—(0+–1) V; relative length of toes I<II<III =V<IV.

Dorsal surfaces varying from smooth to warty; scattered, irregularly distributed white spiculae and warts on flanks; warts on anterior and proximal dorsal surface of fore limb, throat, chest, and belly; undersides of hind limbs rugose, but free of warts; cloacal opening an inconspicuous tube at midlevel of thighs, directed posteriorly; low, elongated warts lateral to cloacal opening.

In preservative (~70% ethanol), cream with black, irregular marks on dorsum of body and limbs. Tips of fingers and toes cream dorsally and ventrally, contrasting to black adjacent phalanges. Dorsum of snout cream. Flanks cream and black, except infraorbital and canthal regions, which are cream. Venter cream anteriorly and cream with five scattered, irregular, black marks posteriorly. Limbs ventrally mostly cream, except at joints with irregular black marks. Palms and soles cream with black marks. Black mark below cloaca.

Measurements (mm). SVL 45.8, TIBL 165, FOOT 18.7, HLSQ 13.2, HDWD 12.0, ITNR 4.6, EYDM 4.5, EYNO 3.3, RDUL 13.8, HAND 12.2, THBL 7.6, SW 14.4.

Variation. Meristic variation is given in Table 1 . Besides larger female size, the forearm in females is not swollen. Nuptial pads of adult males cover dorsum and inner margins of Fingers II and III. Nuptial pads vary from covering only Finger II (KU 117876) to Fingers II and III (KU 142950). When covering Finger III, nuptial excrescences can be more abundant proximally and at inner margin (KU 142954).

Color variation in preservative (~70% ethanol): Specimens from Napo, i.e., Oyacachi and Papallacta show large variation in dorsal and ventral patterns, from dorsum nearly entirely black (KU 117875) to mostly cream (QCAZ 299), and from venter white (KU 117875) to mostly marbled (KU 117879). Thus, they fit well descriptions and illustrations of color patterns in dorsal and ventral views provided by Peters (1973:Figs. 25– 27, under A. pachydermus ) of specimens from the same region. A juvenile (QCAZ 3154, SVL = 17.8 mm) has a fine mid-dorsal line.

Referred Specimens from Provincia Chimborazo (QCAZ 3870, 3871, EPN 3307) are dorsally predominantly black, but have some cream blotches. QCAZ 3871 has a black dorsum with cream blotches, one on the snout, one on the upper eyelid, a small one on the interorbital region, two on the scapular region, and three on the sacral region; the flanks are black with minute white tips of spiculae. The loreal and suborbital regions are cream stippled with brown; the lower lip, throat, and chest are entirely white, whereas the belly and undersides of the limbs are black, except for a large white mark on belly. The palmar surfaces are white, and gray digits contrast with white tips of fingers dorsally, and all of Finger II is white dorsally. The dorsal surfaces of the feet, and soles are black; the ventral surfaces of Toe I, tips of toes, and metatarsal and subarticular tubercles are white. QCAZ 3870 differs from the previous individual by having the dorsum posterior to the head entirely black, whereas the dorsum of the head is mostly black with diffuse gray on the snout; the belly has four cream blotches and palms are mostly cream. EPN 3307 differs from QCAZ 3871 by having the dorsum of head mostly cream and four asymmetrical cream round blotches on the dorsum of the anterior part of body, the throat with a small black blotch, and the belly with a large white mark

Color in life. Peters (1973:35) described specimens from Provincia Napo (Chalpi, Oyacachi and Papallacta) as follows: “The lighter dorsal areas are bright yellow. Many of the warts and pustules have white tops. The ventral surfaces are white in almost all individuals, but some may have orange areas or spots and some have red bellies.”

USNM 193518 has yellowish green spotting on dorsum and a bright orange belly (Field Notes of James A. Peters, 5 July 1962). KU 117874–75 is black above, 117874 is red below, 117875 is orange; metatarsal tubercles are yellow; KU 117876– 79 juveniles are black above with dark faintly yellow blotches; black and white below. All specimens except 117879 are white below with black markings; in 117879 there is pale red pigment in the white areas posteriorly and dorsum black with few to many yellow spots. KU 117879 has yellow-white spots on back; flanks black with white spots; metatarsal tubercles white; iris dark brown (Field Notes of John D. Lynch, 7 March 1968). KU 142950, dorsum yellow and black; venter white and black; iris reddish brown (Field Notes of William E. Duellman, 27 October 1971). KU 142951–52, dorsum black with greenish yellow markings; venter black and white (Field Notes of William E. Duellman, 17 October 1971). KU 142953, dorsum green and black; KU 142954, yellow and black (Field Notes of William E. Duellman, 28 October 1971).

Lötters (1996: Fig. 11 ) and Coloma and Ron (2001:Fig. 29) provided color photographs of MHNG 2246.93 from 11 Km ESE of Papallacta. Almendáriz and Cisneros (2005:155) provided a color description and photograph of this species.

Referred specimen EPN 3307 from Provincia Chimborazo had a black dorsum, bearing scattered, small, greenish-yellow marks mostly on the cephalic region; venter with two yellow marks separated by a black stripe that extends toward dorsum (Field Notes of Ana Almendáriz, 19 September 1986).

Morphometric comparisons. SVL is not significantly different between females from Provincia Napo vs. Provincia Chimborazo (t = 0.342, df = 9, P = 0.7402). No males from Chimborazo are available for comparisons.

Two components with eigenvalues> 1.0 were extracted from the PCA of eight morphometric variables of 26 specimens from populations throughout the range of Atelopus petersi . The axes accounted for 57.5 % of the total variation. Along PC I, the highest loadings were for FL and HLSQ. Along PC II, the highest loadings were for SW and SVL. There is a wide overlap among the morphometric range of these populations.

Comments. The Provincia Chimborazo population seems conspecific with Atelopus petersi . However, at this time, further analyses are precluded by the small sample size (three females) from Provincia Chimborazo. Because this small sample size, we preferred to list the Provincia Chimborazo specimens as referred material and not as paratypes.

Peters (1973) discussed a series of specimens in the Gustavo Orcés collection (GOV 8698–700, currently USNM 236942–44) resembling Atelopus petersi (i.e., A. pachydermus sensu Peters, 1973 ), from the Andes of Provincia Loja in southern Ecuador. He stated that these specimens were identical to those from Oyacachi. However, these specimens are unicolor cream, in contrast to Oyacachi specimens. Because at that time A. petersi ( A. pachydermus sensu Peters, 1973 ) was unknown from the area between Napo and Loja, Peters (1973:37) suggested that the locality data were erroneous. However, we prefer to assume that the Loja population may refer to a distinct (unnamed) taxon, although they are morphologically similar. Our PCA analysis shows that morphometric variation between the Loja specimens and A. petersi widely overlaps. Our assumption is based on the large geographic gap between A. petersi and the Loja population. Nonetheless, resolution of this issue will require further analyses of Atelopus specimens and populations from intermediate areas and from Loja and Azuay.

Distribution, ecology and current population status. According to our data, Atelopus petersi occurs in the Cordillera Oriental of the Andes in Ecuador, Provincias Napo and – according to specimens tentatively referred to the new species – Chimborazo ( Fig. 6 ), at elevations of 2660–3300 m above sea level. The area in which A. petersi occurs includes Cloud Montane Forest and High Montane Evergreen Forest, following the classification of the natural plant formations of the Ecuadorian Andes ( Valencia et al., 1999). Annual mean precipitation is about 1000–2000 mm and annual mean temperature is about 12–18ºC ( Cañadas-Cruz, 1983). According to Peters (1973), A. petersi (as A. pachydermus ) occurs sympatrically with A. ignescens sensu stricto ( Cornalia, 1849).

Knowledge on the life history of Atelopus petersi is poor. KU117874–79 were collected on 7 March 1968 under rocks at the edge of a stream. KU 142950 was collected in 27 October 1971 in streambed by day. KU 142951–54 were collected in 17, 27 and 28 October 1971 under logs on grassy hillside. The referred specimen EPN 3307 (female) was collected active on cushions plants in paramo habitat at 10:59 hrs on 19 September 1986. QCAZ 298–302 (two males, three females) were collected on April 1988 during the day when active on a trail. A juvenile (QCAZ 3154) was collected on 30 March 1988. QCAZ 4555 (female) was collected on 19 August 1993 when walking along the border of the Río Oyacachi. QCAZ 7678 was found dead, at 1 Km E of Oyacachi, on 8 November 1996. This is the latest record for this species from Provincia Napo. Despite occasional efforts to locate A. petersi subsequently (one visit to Oyacachi on September 2003, two visits to 11 Km East of Papallacta on January and August 1999, four visits to Atillo on May 2001, on 15 and 30 June 2002, and on April 2006), no additional individuals have been found. According to Peters (1973:36), in the past, A. petersi was “extremely common” in the vicinity of Papallacta, where it was found along the Río Papallacta, under rocks in moist, and spongy runoff areas. Interviewing local people at Oyacachi and Papallacta, they were familiar with these toads. Several different-aged persons revealed that these toads once were abundant but have not been seen for several years, although in Oyacachi some people claimed, on September 2003, that from time to time they still see single individuals.

Remarks. The color pattern of specimen JAP 2267 of Atelopus petersi , and depicted on Figs. 26–27 in Peters (1973) from the environs of Papallacta conforms well to the color pattern of the holotype of A. bomolochos (CAS 91930; Peters, 1973: Fig. 15 ). This resemblance might be homoplastic, plesiomorphic, or indicate a close phylogenetic affinity between them.

Etymology. The specific name is a noun in the genitive case and it is a patronym for James A. Peters, in recognition of his discovery of this species in 1962 and posterior detailed description in 1973. As well, we recognize his contribution to Atelopus taxonomy.

Figures

FIGURE 3. (A) Atelopus pachydermus from Cutervo, Peru (no museum number associated, photo AML); (B, C) A. bomolochos from 10 Km S Cutchil, Provincia Azuay (KU 217443 – 44, photos LAC); (D) A. bomolochos from 19 Km S Cutchil, Provincia Azuay (KU 217445, photo LAC); (E, F) A. onorei from Río Chipla, Provincia Azuay (no numbers associated, photos LAC).

FIGURE 5. Holotype of Atelopus petersi (QCAZ 300): (A) female, SVL = 47.9 mm; (B) ventral view of right hand, enlarged 3.2 times of A; (C) ventral view of left foot; enlarged 3.2 times of A.

FIGURE 6. Map of Ecuador showing localities of Atelopus petersi, (circles), A. bomolochos (squares) and A. onorei (triangle). 1 = Provincia Napo: Oyacachi; 2 = Provincia Napo: Chalpi; 3 = Provincia Napo: 11 Km ESE Papallacta; 4 = Provincia Chimborazo: Lagunas de Atillo, Laguna Cuyug (specimens tentatively referred to A. petersi); 5 = Provincia Azuay: Sevilla de Oro; 6 = Provincia Azuay: Cuenca; 7 = Provincia Cañar: Juncal-General Morales; 8 = Provincia Azuay: Río Chipla, 10 – 15 Km E Luz María.

FIGURE 11. Skeletal features of female Atelopus petersi from Oyacachi, Provincia Napo (QCAZ 302, SVL = 42.2 mm). (A) ventral view of hyobranchium, (B) dorsal view of vertebral column and pelvic girdle, and (C) ventral view of pectoral girdle. Scale = 3 mm.

FIGURE 15. Manus (A) and pes (B), in ventral view, of female Atelopus onorei from Río Chipla, Provincia Azuay (QCAZ 1868). The arrow designates the Sesamoid I. Stippled areas are bone; cartilage shown in dark gray. Broken line indicates missing phalanx. Scale = 2 mm.