Leptodactylus latinasus

Borteiro, Claudio & Kolenc, Francisco, 2007, Redescription of the tadpoles of three species of frogs from Uruguay (Amphibia: Anura: Leiuperidae and Leptodactylidae), with notes on natural history, Zootaxa 1638, pp. 1-20 : 3-6

Leptodactylus latinasus

Tadpole external morphology. The tadpoles of Leptodactylus latinasus ( Fig. 2 A, B) belong to the benthic ecomorphological guild (section II: A: 1) of McDiarmid and Altig (1999) as revised from Altig and Johnston (1989). Tadpoles at stages 34–36 are about 23.1 ± 2.0 mm of total length, and they have a depressed body (BMH/BMW = 0.75 ± 0.13). The body length is about 40% of total length (BL/TL = 0.40 ± 0.02), body shape is ovoid in dorsal view and the maximum width is placed at the beginning of the spiracular tube. In lateral view, the ventral contour of the body is slightly convex. The snout is slightly truncated in dorsal and lateral views. The nostrils are oval; they are dorsolaterally positioned (EN/BWE = 0.74 ± 0.02), closer to the tip of the snout than to the eyes (FN/ END = 0.63 ± 0.10), more visible laterally than dorsally and its opening is laterodorsally directed. The eyes are large (E/BWE = 0.47 ± 0.02) and dorsolateral (IOD/BWE = 0.65 ± 0.19), not visible from ventral view. Pineal organ and lateral line system were not visible. The spiracle is single, lateral, sinistral, short, with its inner wall entirely fused to the body, and it is placed at the middle of the body length (RSD/BL = 0.56 ± 0.02), posterodorsally directed; its opening is oval, with a small elevated rim, being its diameter slightly smaller than the tube diameter, and is visible only laterally. The intestinal assa was usually observed approximately at the center of the abdominal ventral surface, but in two exemplars was left sided. The vent tube is medial, and in one specimen it opened to the left due to a fold in the origin of the ventral fin. The tail is large (TAL/TL = 0.60 ± 0.02), and both fins are slightly higher than the body height (FH/ BMH = 1.19 ± 0.47). The dorsal fin originates at the body-tail junction and it has a regularly curved, convex free margin. The ventral fin originates from the longitudinal axis of the posterior wall of the vent tube and its free margin is convex. The tail axis is straight, and the tail smoothly stretches towards the tip, ending rounded. The tail musculature almost reaches the tail end. The oral disc ( Fig. 2 C) is anteroventral, medium sized (OD/ BMW = 0.37 ± 0.03), lacks lateral constrictions (not emarginated) and has a large dorsal gap (DG/OD = 0.62 ± 0.02). Marginal papillae are usually arranged in a single row on both sides of the dorsal gap, in a double row in sub angular regions, and in a single or double row in the ventral portion of the oral disc. Papillae are simple, longer than wide, subconical, with rounded tip. Submarginal papillae are absent. The upper jaw sheath is widely arch-shaped, and the lower jaw sheath is V-shaped. Both jaw sheaths are well developed, finely serrated and heavily pigmented on their distal halves. Labial tooth row formula is 2(2)/3(1), the gap present in A2 is wide but that of P1 is very narrow. The length of P3 is about a half to two thirds the length of other tooth rows. Measurements are shown in Table 1 .

Tadpole in vivo coloration. The body is brown dorsally and laterally with greenish shines, with a light fine reticulated black pattern visible with magnification. The ventral surface of the body is yellowish with scarce dark pigmentation, and greenish and golden shines. Caudal musculature is brown, also with greenish shines and ventral irregular yellowish areas in the first half. Both fins are irregularly pigmented with dark blotches, which are less intense in the anterior part of the ventral fin. The iris is light yellow.

Tadpole coloration in preservative. The body and caudal musculature coloration turns light brown. The ventral surface of the body has a less intense coloration and unpigmented areas in the gular region and in the centre of the abdomen. The coloration of both fins lightens and the small dark blotches of melanophores are more numerous along the upper half of the dorsal fin. The myomers become more evident in the two distal thirds of the tail.

Tadpole morphological variation: Lot ZVCB 15187, three tadpoles at stage 40, papillation and LTRF present the same characteristics as in lot ZVCB 15186.

Figures

FIGURE 2. The tadpole of Leptodactylus latinasus, stage 34, ZVCB 15186. A. Lateral view. B. Dorsal view. C. Oral disc. Scale bars = 5 mm (A, B), and = 1 mm (C).

Tables

TABLE 1. Measurements (in millimeters) of tadpoles of Leptodactylus latinasus, Physalaemus riograndensis and Physalaemus biligonigerus from Uruguay (mean ± standard deviation, range given in parentheses); see measurement explanation in the text.

Variable L. latinasus (Montevideo, n = 10, stages 31–36) TL 23.1 ± 2.0 (19.6–26.4)	P. riograndensis (Artigas, n = 10, stages 31–36) 14.7 ± 1.0 (12.8–15.9)	P. biligonigerus (Treintay Tres, n = 6, stages 34–36) 23.6 ± 1.3 (21.4–25.0)
BL 9.1 ± 0.7 (7.8–10.0)	5.8 ± 0.4 (5.0–6.3)	10.2 ± 0.7 (9.4–11.2)
TAL 13.9 ± 1.5 (11.8–16.7) BMW 5.4 ± 0.4 (4.4–5.9)	8.9 ± 0.7 (7.8–10.0) 4.0 ± 0.2 (3.7 –4.2)	16.9 ± 1.1 (15.2–18.0) 7.2 ± 0.5 (6.5–7.9)
BWE 2.3 ± 0.1(2.1–2.5)	3.2 ± 0.2 (2.9–3.5)	5.5 ± 0.4 (5.0–6.0)
BWN 5.1 ± 0.7 (4–6.2) BMH 4.1 ± 0.9 (1.8–4.9)	2.1 ± 0.1 (1.9–2.3) 2.9 ± 0.2 (2.6–3.1)	3.8 ± 0.3 (3.4–4.3) 5.7 ± 0.3 (5.3–6.2)
FH 4.5 ± 0.4 (4.0–5.0)	3.2 ± 0.2 (2.9–3.6)	5.9 ± 0.4 (5.5–6.3)
RSD 5.1 ± 0.4 (4.4–5.4) FN 0.6 ± 0.1 (0.5–0.8)	3.8 ± 0.3 (3.3–4.2) 0.4 ± 0.1 (0.4–0.5)	6.6 ± 0.7 (5.8–7.7) 1.0 ± 0.2 (0.7–1.4)
END 0.9 ± 0.1 (0.9–1.0)	0.4 ± 0.0 (0.4–0.5)	0.8 ± 0.1 (0.7–0.9)
N 0.2 ± 0.0 (0.2–0.3) E 1.0 ± 0.1 (0.9–1.2)	0.3 ± 0.0 (0.3–0.4) 0.9 ± 0.1 (0.6–1.0)	0.3 ± 0.0 (0.2–0.3) 1.5 ± 0.1 (1.3–1.6)
EN 1.7 ± 0.1 (1.6–1.8)	1.1 ± 0.1 (1.1–1.3)	1.5 ± 0.1 (1.4–1.5)
IN 1.2 ± 0.1 (1.1–1.4) IOD 1.5 ± 0.4 (1.0–2.4)	0.6 ± 0.1 (0.5–0.7) 2.1 ± 0.1 (1.9–2.3)	1.0 ± 0.2 (0.9–1.4) 3.4 ± 0.4 (2.9–4.0)
TMW 1.7 ± 0.1 (1.5–2.0)	1.1 ± 0.1 (0.9–1.2)	2.0 ± 0.1 (1.9–2.2)
IO 0.8 ± 0.3 (0.7–1.7) OD 2.0 ± 0.1 (1.9–2.2)	0.9 ± 0.1 (0.9–1.0) 1.2 ± 0.1 (1.1–1.4)	1.5 ± 0.1 (1.3–1.6) 2.0 ± 0.2 (1.8–2.3)
DG 1.3 ± 0.1 (1.0–1.4)	0.8 ± 0.1 (0.8–1.0)	1.3 ± 0.1 (1.2–1.5)