Subarticular Tubercles Research Articles

A New Species of Rhacophorus from Eastern Thailand (Anura: Rhacophoridae)

A new tree frog of the genus Rhacophorus is described on the basis of specimens collected from Kalasin and Roi Et Provinces, eastern Thailand. It can be distinguished from all other congeners by the combination of: moderate body size (about 38 mm in males and 44 mm in females); brownish dorsum with irregular, dark marking; third finger webbed broadly to base of disk or less on outer side, and fourth finger to distal subarticular tubercle or base of disk; and no dermal appendage on snout, vent, or heel. It is currently known only around the type locality, where habitats suitable for anurans are limited.

New Species of Nyctibatrachus (Anura: Ranidae) from Castle Rock, Karnataka State, Southwest India

Abstract A new species of ranid frog of the genus Nyctibatrachus is described from Castle Rock, Karnataka State, Southwest India. The new species is compared with all known congeners and is diagnosed by the following combination of characters: head wider than long; snout projecting beyond mouth; supratympanic fold poorly defined; webbing on toes reaching base of disks except on Toe IV, where it reaches distal subarticular tubercle; tips of digits on fingers and toes flattened to form disks with distinct grooves separating dorsum of disks from venter; and femoral gland present. The largest specimen in the type series has a snout-vent length of 43.2 mm. Nyctibatrachus hussaini Krishnamurthy, Reddy and Gururaja, 2001, is shown to be an invalid nomen, for lack of typification.

Three New Species of Narrow-Mouth Frogs (Genus: Microhyla) from Indochina, with Comments on Microhyla annamensis and Microhyla palmipes

Abstract Three species of Microhyla from Indochina are described. One species is from the Northern Truong Son (Annamite Highlands) of Vietnam and Laos, characterized by finger I less than one-half the length of finger II; expanded disks at the tip of the digits with dorsal median longitudinal grooves producing the appearance of two scutes; two metatarsal tubercles; extensive webbing on feet: on toe IV web full to distal subarticular tubercle; and marbled belly. The second species is from the Tay Nguyen Plateau, Gia Lai Province, Vietnam. It is smaller than the above species, has full webbing to medial subarticular tubercle of toe IV, and has a dusted belly. Microhyla annamensis is discussed because of its similarity to the two new species above. A third species of Microhyla is described from Ngoc Linh Mountain in Quang Nam Province, Vietnam. It is easily separated from congeners of Indochina and China by its small size and the appearance of the first finger as a small, partially free nub. Microhyla palmip...

Intraspecific Variation in Cranial Ossification in the Tailed Frog, Ascaphus truei

We describe the sequence of cranial ossification in the Tailed Frog, Ascaphus truei, and examine intraspecific variation in the timing and sequence of cranial development. Because tadpoles of A. truei lack the subarticular tubercles that normally delineate Gosner stages 39 and 40, we provide a modified Gosner staging system more appropriate for this species. Ossification sequence was highly variable among the populations and greater than that reported for other anuran species. In general, early ossification events in A. truei are similar to that reported for other anuran species. However, compared with other taxa, both onset of initial ossification events and appearance of specific elements appear relatively later in the development of Ascaphus.

A New Species of Rana from the Terai of Nepal

new species of Rana is described from the terai region of Nepal on the basis of three specimens. The new species is diagnosable from known congeners in possessing the following characteristics: head longer than wide; tympanum rounded, smaller than orbit diameter; supratympanic fold absent; finger I longer than finger II; a series of large, flat glands on lateral aspect of body; broad webbing on toe IV to penultimate subarticular tubercle, reaching tip of toes as a narrow sheath; tips of digits flattened to form disks with distinct circummarginal grooves separating dorsum of disks from ventrum; tibia length/snout-vent length ratio 47.23-54.15; and absence of humeral gland on forelimb of males. The snout-vent length range shown by the type series is 30.4-32.5 mm.

A new genus and species of petropedetine frog (Amphibia Anura Ranidae) from high altitude in the mountains of Ethiopia

A new genus and species, Ericabatrachus baleensis, is described from forested localities in the Bale Mountains of Ethiopia. The new taxon seems most closely allied to Petropedetes Reichenow 1874, from West Africa, and to Arthroleptides Nieden 1910, which is found in Kenya and Tanzania. It resembles these genera in being associated with fast-flowing forest streams and there is circumstantial evidence of a terrestrial life cycle, perhaps similar to that observed in some species of Petropedetes. Morphological features which are considered to justify the recognition of a new genus include the small size and distinctive habitus of the animal, significantly reduced first finger and subarticular tubercles, and a striking ventral colour pattern.

A New and Peculiar Species of Rhamphophryne (Amphibia: Bufonidae) from Antioquia, Colombia

A new species of Rhamphophryne is described from Murri in the Department of Antioquia, Colombia. The most distinctive and unique features of the new species are that the stomach wall is adherent to the abdominal wall and that, contrary to the condition in other Rhamphophryne, there is a reduced tympanic apparatus. The new species is also characterized by having a rostral keel, a palpebral crest, subarticular tubercles in both hand and feet, and a protruding angle of the jaw. It is also the largest species of Rhamphophryne so far known.

A New Frog of the Genus Eleutherodactylus from Western Panama

A New Frog of the Genus Eleutherodactylus from Western Panama

Treefrog toe pads: comparative surface morphology using scanning electron microscopy

Scanning electron microscopy of toes and toe pads of a large number of species of frogs reveals many features of possible systematic or functional significance. The adhesive pads evolved through progressive development of specialized columnar epidermis at the digital tips, in tandem with increased arborealism. Mucous pore morphology and density on the pads will distinguish between evolutionarily convergent hylid and rhacophorid treefrogs. Larger pads and accessory adhesive areas on subarticular tubercles allow large treefrogs to compensate for allometric increase in mass relative to surface area. Other characters of potential systematic or evolutionary significance are discussed. As anuran toe pads have been used previously for systematics, the use of scanning electron microscopy in this regard is advocated.

Hyla langei, a New Frog from Parana, Southern Brasil

DESCRIPTION OF HOLOTYPE. -Adult male (total length 66. O0 mm). Head broader (23. 0 mm) than long; snout not projecting, rounded in lateral profile (Figure 4); canthus well defined; loreal region concave; tympanum very small (2. 2 mm in diameter), nearly circular, indistinct and partially hidden under the supratympanic fold, little more than one-fourth the diameter of eye, and separated from the posterior border of eye by a distance nearly twice its own diameter. Supratympanic fold well developed. Eye projected antero-laterally, its transverse diameter (8. 2 mm) larger than the distance from eye to nostril (5. 2 mm). Nostrils placed under the canthus rostralis and directed slightly backward. Interorbital distance, nearly the same as the horizontal diameter of eye. Internal nares nearly circular; vomerine teeth in two separate patches, between and posterior to the internal nares (Figure 5). Tongue large and flat, nearly circular, slightly free and notched behind, occupying nearly the entire floor of the mouth. Vocal sac subgular; slits under the margin of the tongue. Fingers webbed at base, with well developed terminal discs larger than tympanum. First finger with a well developed bifid prepollex (Figures 2, 3). Subarticular and supernumerary tubercles well developed; carpal tubercles poorly differentiated. Forearm greatly thickened, almost as in certain Leptodactylus. Upper arm with a humeral crest and a humeral hook similar to the condition in Hyla martinsi. Hind limbs normal, heels barely overlap when legs are folded at right angles to axis of body; tibio-tarsal articulation reaches to eye. Toes three-fourths webbed; the web reaches the disc of toes 3 and 5 and the penultimate phalange of toe 4. Discs of toes slightly smaller than those of fingers; subarticular and supernumerary tubercles well developed; only one tarsal tubercle, on the base of first toe; tarsalfold poorly developed. Skin of dorsum nearly smooth; ventrally the skin is smooth in the gular region and becomes more granular posteriorly; abdomen and ventral surface of thigh very granular. The coloration is faded in this preserved specimen. The dorsum is brown; the sides of the head and body are lighter. The concealed surfaces of the thighs and ventral surface of the body are very light brown. The dorsal surfaces of the forearms, thighs, tibiae, and tarsi have indistinct light cross bars.

A New Phyllomedusa from Venezuela

Diagnosis.-A Phyllomedusa in which the first toe is shorter than the second, disks of fingers and toes wider than the digits, fingers free, rudimentary web between outer toes, exposed dorsal surfaces uniformly covered with minute granules, irregular white spots and smaller irregular dark spots on dorsum. Holotype.-Estacion Biologica de Rancho Grande (Edo. Aragua, Venezuela), adult male, 40 mm snout-to-vent, from the biological station Henry Pittier, collected by Sr. Gonzalo Medina Padilla, 1960. Paratype.-Stanford University 20379, adult female, 49 mm snout-to-vent, with the same data as holotype. Description of holotype.-Vomerine teeth absent. Tongue entire behind. Tip of snout bluntly rounded when viewed from above, truncate in profile (Fig. la); canthus rostralis fairly distinct, almost straight; loreal region oblique, plane. Head broader than long, much wider than sacrum. Interorbital distance broader than upper eyelid, slightly greater than the horizontal diameter of exposed part of eye and slightly greater than distance from the anterior corner of eye to nostril. Nostrils closer to tip of snout than to eye; distance between nostrils equal to distance from the anterior corner of eye to the nostril. Tympanum distinct, its vertical diameter equal to one-third the horizontal diameter of the exposed part of eye. Fingers free, flattened in cross section. Subarticular tubercles prominent. Disks well developed; disk of third finger equal to tympanum, disks of other fingers smaller. Toes free, except for slight web between fourth and fifth toes; first toe slightly shorter than the second, not opposable to the others. Disks well developed, only slightly broader than digits; all disks except that of fifth toe smaller than tympanum. No fringes on fingers or toes (Fig. lb). Heels overlap very slightly when held at right angles to the body. Tibiotarsal articulation reaches to nostril.

Anuran Amphäbios from the Adolpho Lutz Collection; Hyla Claresignata Lutz & B. Lutz, 1939

Hyla claresignata Lutz & Lutz, 1939, is a large species apparently not closely allied to the other known Brazilian hylas. It is characterized by the very small tympanum; the head is short and the snout rounded; the legs are long, the hands and feet unusually large, the latter extensively webbbed. The specific name is derived from the insular, irregular, or roughly triangular, dark spots, with a light halo, found mostly in the dorso-lateral region and on the legs. It belongs to the rain-forest fauna of the Maritime Range. The adult is a bromeliad-dweller and the tadpole rhyacophilous. DESCRIPTION. Vomerine teeth in two separate, oblique, groups, behind the large choanae, parallel to the posterior half of their inner border. Tongue entire, short, very broad and hardly free behind. Snout short, rounded, with distinct canthus rostralis and gradually sloping loreal region. Eye very large and prominent, its horizontal diameter almost equal to the distance between its anterior corner and the tip of the snout. Tympanum very small, less than one third of the diameter of the eye, but distinct, partly covered by a short, heavy ridge. Lateral fingers less than one third webbed; fourth finger slightly longer than the second, just reaching the base of the disk of the third; subarticular tubercles well developed; an angular pollex rudiment, more noticeable in the males. Toes almost completely webbed, the edge of the web inserted at the base of the disk on the third and the fifth; an inner metatarsal tubercle. Skin smooth above, granular beneath, on the throat minutely so. No dermal appendage on the hell. Habit robust, head broader than long, body rather heavy, slightly narrowed in the postaxillary region. Legs long, the tibiotarsal articulation reaching beyond the tip of the snout when adpressed. Type (female): 61 mm. (Fig. 1.) DIAGNOSIS of TADPOLE (by G. Orton). A large specialized, mountain-stream tadpole, with wide head an elongated, flattened snout, greatly enlarged lips and high tooth formula. Eyes dorsal. Spiracle sinistral, projecting, situated far back on side. Anus dextral. Tooth formula 8/12 to 9/14 in fully grown larvae. Tail with a prominent, vertical dark band across musculature and fins; a second concentration of dark pigment near tip of tail, may or may not form a similar but narrower band. Maximum known total length: 60mm.; head and body length 25mm. (Figs. 6 e 7). For further details see Lutz & Lutz, 1939 and Lutz B. & Orton G. 1946.

The digital pads of the tree frogs. A study of the phylogenesis of an adaptive structure

AbstractThe digital disks of the tree frogs are covered ventrally with a superficial layer of vertically elongated, fibrous, and distally free cells between which there empty a series of convoluted mucous glands. The latter are surrounded and, in the larger‐disked species, divided into blocks by sheets of collagenous fibers. The glands are emptied by the squeezing together of the collagenous fibers when the body weight exerts a pull on the terminal phalanges. The disks function by friction, cohesion, and adhesion.The digital‐disk apparatus was fully established before certain groups of frogs became arboreal. It is retained in others which have reverted to the terrestrial habit. The intercalary cartilage increases the efficiency of the apparatus. It did not arise in phylogeny until after the apparatus was developed.As the digital disks vary in extent in both arboreal and terrestrial species, arborealism seems to have resulted from a chance occurrence of large disks in the smaller‐bodied forms; at least, there is no progressive modification of the digits toward particular habitat requirements.The subarticular tubercles of many Salientia develop typical climbing apparatus. This may or may not be correlated with an arboreal habit. In the species with the largest subarticular tubercles no apparatus is present. Arboreal salamanders exhibit no special climbing mechanism, but adhere by pressing their moist integument against the substratum.