Centrolene bacatum WILD 1994

CENTROLENE BACATUM WILD, 1994

Diagnosis: A species that differs from other species in the family by the following combination of characters: (1) vomerine teeth absent; (2) in life, bones green; (3) in preservative, parietal peritoneum white, pericardium silver white, hepatic peritoneum clear, digestive tract and kidneys cream; (4) in life, dorsum dark green with white warts; in preservative, dorsum lavender with small white spots; (5) no webbing between Fingers I and II; webbing between outer fingers reduced, II 2–3 1/3 III 2 1/2 −2 1/4 IV; (6) webbing formula on foot usually I 1 1/2 −2 + II 1–2 III 1 + —2 1/4 IV 2 1/2 −1 + V; (7) snout rounded in dorsal aspect, bluntly rounded in lateral profile; (8) dorsal skin finely shagreen with few white warts and tiny spinules; (9) ulnar and inner tarsal folds low or absent; outer tarsal fold absent; (10) humeral spine present; (11) tympanum orientated almost vertically, with slight posterior and lateral inclinations, tympanic annulus visible except for dorsal border, which is covered by supratympanic fold; tympanic membrane pigmented, differentiated from surrounding skin; (12) SVL in males 19.4–21.8 mm (mean = 20.6; n = 9); in one female 20.9 mm; (13) prepollical spine not protruding externally; males with large, unpigmented nuptial excrescence (Type I of Flores, 1985); (14) several small, white tubercles immediately posteroventral to vent; pair of large, round tubercles posteroventral to vent (as illustrated by Lynch & Duellman, 1973: fig. 2A); (15) when adpressed, Fingers I and II about equal in length (Finger I 91.3–104.5% of Finger II); (16) liver tetralobed; (17) diameter of eye about twice width of disc of Finger III.

Centrolene bacatum is easily distinguished from other species in YBS by having white tubercles in an area that extends from below the eye to the insertion of the arm (Wild, 1994: fig. 3). Additionally, Centrolene bacatum is smaller than C. buckleyi [SVL in males, 19.4–21.8 mm (n = 9) in C. bacatum; 25.0– 34.7 mm (n = 20) in C. buckleyi] and has a snout that is bluntly rounded in lateral profile (sloping in C. buckleyi). Characters differentiating species in the Centrolene prosoblepon group are summarized in Table 1.

Colour in life: Dorsum dark green with cream lateral stripe continuing as a series of cream tubercles under eye; throat and ventral surfaces of limbs green; digits pale green; parietal peritoneum white; visceral peritoneum clear; bones green; iris pale bronze with black reticulation (W. E. Duellman field notes 4 March 1984, in Wild, 1994; Fig. 4F).

Colour in preservative: Dorsum of head and body lavender with small, unpigmented spots and white warts; limbs cream lavender with numerous small, unpigmented spots and some white warts; white warts on lateral surface of head; conspicuous white border on the upper lip, lower lip lacks white pigmentation; tympanum pigmented with purple specks; cloacal region with cream or white warts; iris silvery white with dark purple reticulation. Dorsally, Fingers I and II and Toes I–III unpigmented; some pigmentation visible on Fingers III and IV and Toes IV and V. A male (QCAZ 22386) was dissected to determine coloration of internal organs: white parietal peritoneum covering the anterior half of the belly, silvery-white pericardium, clear hepatic peritoneum, cream visceral peritoneum, and cream kidneys.

Distribution, ecology, and natural history: Centrolene bacatum is known from three localities: 11.2 km

Snout

(lateral Texture of dorsal Dorsal coloration Teeth on Webbing on Finger view) skin of males in preservative vomer IV Webbing on Toe V

SVL in adult males (mm)

Source

C. altitudinale Round to Shagreen with Lavender with Absent Reaching level of Reaching level of slightly small spinules white spots distal subarticular distal subarticular sloping tubercle tubercle

C. andinum Round to Shagreen Lavender to Present Reaching level of Reaching level of slightly cream lavender distal subarticular intercalary cartilage sloping with dark purple tubercle spots

C. audax Truncate Shagreen with Lavender with Present Reaching level of Reaching level of spinules and white warts distal subarticular intercalary cartilage white warts tubercle

C. bacatum Bluntly Shagreen with Lavender with Absent Reaching level of Reaching level of rounded spinules and white warts distal subarticular intercalary cartilage white warts tubercle

C. ballux Bluntly Shagreen Lavender with Absent Reaching level of Reaching level rounded small cream distal subarticular between distal flecks tubercle subarticular tubercle and intercalary cartilage

C. buckleyi Slightly Shagreen with or Lavender with or Absent Usually not Reaching level sloping to without small without whitish reaching level of between distal sloping warts and warts distal subarticular subarticular tubercle spinules tubercle and intercalary cartilage

C. fernandoi Round Shagreen with Lavender with Present Reaching level of Reaching level of spinules and white warts distal subarticular intercalary cartilage white warts tubercle

C. grandisonae Round Pustular Lavender with Usually Reaching level of Reaching level yellowish warts present distal subarticular between distal tubercle subarticular tubercle and intercalary cartilage

21.5–24.5 (n = 12)

21.5–25.1 (n = 16)

23.0–23.6 (n = 3)

19.4–20.7 (n = 8)

19.2–22.2 (n = 25)

25.0–34.7 (n = 20)

22.5–26.4 (n = 9)

25.1–29.3 (n = 9) Señaris (2001)

Señaris (2001); this work

Lynch & Duellman (1973); this work

Wild (1994); this work

Duellman & Burrowes (1989); this work

This work

Duellman & Schulte (1993); this work

Duellman (1980); this work

C. guanacarum Round Shagreen Pale lavender Present Reaching level of Reaching level with white spots distal subarticular between distal tubercle subarticular tubercle and intercalary cartilage

C. heloderma Sloping Pustular GrEy lavender Absent Reaching level of Reaching level of distal subarticular intercalary cartilage tubercle

C. hesperium Slightly Shagreen with Lavender with Absent Not reaching level Reaching level of sloping spinules irregular distal subarticular between distal pigmentless spots tubercle subarticular tubercle and white and intercalary spinules cartilage

C. huilense Sloping Shagreen with Lavender with Absent Reaching level of Reaching or almost spinules cream spinules distal subarticular reaching level of and purple spots tubercle intercalary cartilage

C. hybrida Round Shagreen Pale lavender Absent Reaching or almost Reaching or almost reaching level of reaching level of distal subarticular intercalary cartilage tubercle

C. ilex Truncate Shagreen Lavender

Present Reaching level of Reaching level of distal subarticular intercalary cartilage tubercle

C. lemniscatus Round Shagreen with Lavender with Absent Reaching level of Reaching level spinules unpigmented distal subarticular between distal spinules tubercle subarticular tubercle and intercalary cartilage

C. muelleri Slightly Finely shagreen Greyish lavender Absent Reaching level of Reaching level sloping with dorsolateral with black spots distal subarticular between distal rows of warts and cream warts tubercle subarticular tubercle and intercalary cartilage

C. notostictum Truncate Shagreen with Pale lavender Absent Reaching or almost Reaching or almost spinules with white spots reaching level of reaching level of distal subarticular intercalary cartilage tubercle

20.6–22.3 (n = 3)

26.8–31.5 (n = 17)

23.0–27.3 (n = 54)

23.6–26.7 (n = 7)

20.0–21.9 (n = 18)

27.0

(n = 1)

27.0

(n = 1)

23.5

19.4–22.7 (n = 31) Ruiz-Carranza & Lynch (1995c)

Duellman (1981); this work

Cadle & McDiarmid (1990)

Ruiz-Carranza & Lynch (1995c); this work

Ruiz-Carranza & Lynch (1991b)

Savage (1967); this work

Duellman & Schulte (1993); this work

Duellman & Schulte (1993); this work

Ruiz-Carranza & Lynch (1991b) west-southwest of Plan de Milagro (03°02′S, 78°35′W, 2350 m), Provincia Morona-Santiago, Ecuador; YBS (0°41′S, 77°53′W; 2100 m), Provincia Napo, Ecuador; and 35 km south-east of San Francisco (01°07′S, 76°49′W, 1950 m), Departamento Putumayo, Colombia. Ten individuals of Centrolene bacatum were found at YBS during 3 years of inventory work; it is the most abundant centrolenid at Yanayacu. Four adult males were found in primary forest and one adult male was found in secondary forest on leaves approximately 130–200 cm above streams. A male (QCAZ 22728) was found close to two egg clutches that were on the upper side (not on the tip) of different leaves; the male was not in the same leaf as the egg clutches, suggesting that the clutches were not being guarded by the male. Egg clutches (QCAZ 28500-01) had 16 and 20 eggs, respectively; embryos have a whitish coloration. Males call from the upper side of leaves.

Remarks: Wild (1994) described Centrolene bacatum and placed it in the Centrolene prosoblepon group; however, there is little support for the monophyly of the group (see Discussion) and we consider this placement as tentative until a well-supported phylogeny is available. Centrolene bacatum was known only from males (Wild, 1994); during our fieldwork, we found one female (QCAZ 17807; SVL = 20.9 mm), which matches the description provided by Wild (1994), except that it has a smooth dorsum (dorsum shagreen with minute spinules in males) and the following foot webbing: I 1 1/2 −2 + II 1 – −2 1/3 III 1 + −2 + IV 2 1/2 −1 V. In males, nuptial pads are more reduced than the Type I described by Flores (1985).