Kaloula pulchra

Vassilieva, Anna B., 2021, Larval morphologyof three syntopic species of Kaloula Gray (Anura: Microhylidae) from Vietnam, Zootaxa 4952 (1), pp. 71-86 : 78-79

Kaloula pulchra

Tadpole description. External larval morphology of Kaloula pulchra is described based on ten tadpoles from Kon Ka Kinh NP (ZMMU A-7575) and is shown in Fig. 4 A,B ; the main morphometric characters and body proportions are given in Table 3 .

In dorsal view ( Fig. 4A ), body broadly oval, with the maximum width at the gills level; snout bluntly rounded. In lateral view ( Fig. 4B ), body depressed dorsoventrally, especially in its rostral part. Eyes lateral, relatively small; pupils oriented laterally. Nostrils closed at the stages under description. Very thin nasolacrimal groove extending laterally from the narial protuberances to the anteroventral margin of the orbit. Lateral line system visible on the dorsum as thin, pale dotted lines. Spiracle ventral, medial, representing a wide tube located at the rear part of the belly and slightly extending beyond its end ( Fig. 5C ). Vent tube medial, oblique; vent opening located at the ventral edge of the ventral fin. Tail moderately long, lanceolate, with a rather broadly tapering, rounded tip. Tail musculature rather weakly developed. Tail fins tall, reaching their maximum height at the medium third of its length. Dorsal fin originating at the level of the body-tail junction; nearly equal or slightly lower than the ventral fin. Sheets of slightly thickened skin visible on the sides of the proximal part of the tail (12–15% of tail length), along the muscular part and the bases of the dorsal and ventral fins. Mouth terminal, without keratinized elements. Upper labium widely arched, slightly concave from the dorsal view, with an even edge; lateral flaps short, rounded, slightly or not extending past the snout outline. Lower labium narrow, Ω-shaped, with a narrow, smooth, irregularly dentate flange ( Fig. 6C ).

Coloration. Vital coloration is almost uniformly light-brown or dark-brown above, sometimes almost black, with delicate yellowish speckling on the tail; belly is paler than the back, end of spiracle and vent tube are unpigmented. Conspicuous yellow lateral stripe runs along the midline of the tail extending from its base to approximately 1/5–1/4 of the tail length; tail axis is darkly pigmented, dorsal fin is with scarce brownish-grey speckling, ventral fin is mostly transparent, especially in its proximal part. Iris is black or dark-grey, with a thin golden rim around the pupil. In preservative, the brown tints fade to blackish and yellowish-grey.

Geographic variations. In comparison with tadpoles from Kon Ka Kinh NP, the larvae from Cat Tien and Yok Don NP display a better visible lateral line system; in tadpoles from Binh Chau–Phuok Buu NR, the yellow lateral stripe on the tail is almost absent or only represented by a short row of yellowish speckles. Moreover, tadpoles from southern areas (Binh Chau–Phuok Buu NR and Cat Tien NP) have relatively shorter tails.

Metamorphs. Young metamorphs of Kaloula pulchra ( Fig. 4C ) have stocky appearance, tuberous skin, and bulging, lateral eyes. Limbs are slender, digits show moderately enlarged rounded tips. Ground coloration is dark brown, with distinct greyish or beige dorsolateral stripes and a wide transversal stripe on the rostral part of the head; the upper arms and dorsal surface of the thigh have pinkish or orange patches; undersides are dark grey or brownish, with a pale grey or blueish marbled pattern. SVL 9.60–12.60 mm (n = 8).

Coexisting tadpoles. In Cat Tien NP, tadpoles of Kaloula pulchra were observed in temporary ponds with larvae of K. indochinensis and other frog species: Glyphoglossus guttulatus , Kalophrynus interlineatus , Microhyla butleri , M. heymonsi , M. mukhlesuri , M. pulchra , Micryletta erythropoda (Microhylidae) ; Chiromantis nongkhorensis , Feihyla vittata , Polypedates megacephalus (Rhacophoridae) ; Occiozyga lima , O. martensii (Dicroglossidae) ; and “ Hylarana ” lateralis ( Ranidae ). In Binh Chau–Phuok Buu NR and Yok Don NP this species also coexists with tadpoles of K. mediolineata .

Figures

FIGURE 4. External morphology of a Kaloula pulchra tadpole from Kon Ka Kinh NP (ZMMU A-7575), Stage 34, TL 25 mm, (A) dorsal view, (B) lateral view, and (C) a young metamorph, St. 46, SVL 12.2 mm. Abbreviations: sp spiracle, v vent. Photo by V. Trounov.

FIGURE 5. Spiracle morphology, in ventral view: (A) Kaloula indochinensis ZMMU A-7570, (B) K. mediolineata ZMMU A-7571, and (C) K. pulchra ZMMU A-7575. Abbreviations: sp spiracle, v vent.

FIGURE 6. Mouthparts morphology, in dorsal view: (A) Kaloula indochinensis ZMMU A-7570, (B) K. mediolineata ZMMU A-7571, and (C) K. pulchra ZMMU A-7575. Abbreviations: llab lower labium, ulab upper labium, pap papillae.