Hylodes dactylocinus Pavan, Narvaes & Rodrigues 2001

Ano Todo

Diagnosis A small species of Hylodes (24-31mm snout-vent length) lacking continuous dorsolateral light stripes, and characterized by a tuberculate dorsal skin. Snout subovoid in dorsal view and rounded-acute in lateral view, hands and feet large compared to body size. Extensive fringing on fingers. Dorsal surface of fingers and toes, and the anteroventral face of thighs with bright white spots in males. Dorsal ground color olive gray mottled with irregular dark spots and gold reflexes. A conspicuous red area around vent in males.

Localities surroundings Serra dos Itatins in São Paulo State, Brazil.

arbusto

perene

Óleo essencial

sementes viáveis

Description of the holotype Body robust, head slightly longer than wide, its length contained about three times in snout-vent length; snout subovoid and slightly acuminate in dorsal view, rounded acute in lateral view, its foremost projection well beyond the jaw; eyes large, lateral, their diameter much larger than the eye-nostril distance and slightly shorter than internasal distance; interorbital space approximately equal to the width of the superior eyelid; eye-nostril distance smaller than width of the superior eyelid and that of interorbital space; canthus rostralis distinct, straight; loreal region concave vertical; nostril small, protuberant, directed laterally, closer to the snout tip than to the eyes; tympanum distinct, circular, its diameter about half of the eye diameter; supra tympanic fold weak; well-developed paired lateral vocal sacs; vomerine teeth between and behind choanae, in two small and distinctive clusters; tongue large, oval; ventral margin of upper jaw with horny asperities. Arm long and robust without dermic fold; arm and forearm approximately of the same thickness; hand large with well-developed lateral fringing on fingers; finger discs large, with a pair of scutes on upper surface; subarticular tubercles simple, round and moderately developed; outer and inner metacarpal tubercles rounded, the inner smaller, 1/2 to 1/4 of the outer; finger lengths I < IV < I1 < III; thumb without spines or nuptial asperities. Leg long, thigh and tibia together longer than snout-vent length; toe discs large, upper surfaces with well-developed scutes; well-developed toe fringing; a trace of basal webbing due to confluence of fiinging on sides of toes; toe lengths I < II < V < III < IV; subarticular tubercles round, pronounced; well-developed tarsal flaplike fold, extending continuously from the base of the first toe to the tibio-tarsal articulation; metatarsal tubercles developed, the outer conical, about three times smaller than elongated inner. Dense array of irregularly disposed granules in the skin of dorsum, extending from behind the eye, concentrated on the flank, to level of vent. Belly smooth with a tranverse semicircular dermic fold in the posterior part of the abdomen. Color in life: Dorsum dark gray with olive green irregular spots and gold reflections. Lateral tubercles on body bright, whitish. A wide, white-gold dorsolateral stripe extends from midbody to groin. Belly whitish and bright, with small dark spots; throat bright white. A series of bright and conspicuous pearly white spots below the tympanum and the eye. A series of large, bright pearly spots on ventral surface of leg and internal area of the arm; armpit yellowish. Dorsal surface of the fingers I and II, distal half of finger III and, dorsal surface of foot and toes bright white in males. Dorsal surface of the feet gray with darker spots in females. External dorsolateral surface of the feet gilded, extending to fingers IV and V. A dark small area below vent, and a dorsolateral red-copper colored on vent in males; below vent the ground color is gold with some small brighter gold spots reaching the inner part of thigh. Color in preservative: In preservative (70% alcohol), the colors are similar to those in life, except the red coloration laterally to vent and the gilded tonality of the spots on the dorsum have faded or disappeared. Measurements of the holotype (mm): snout-vent length 25.4; head length 9.2; head width 8.1; internarinal distance 2.7; eye-nostril distance 1.9; ESD 3.8; IOS 2.4; eye diameter 3.1; tympanum diameter 1.8; HAL 8.5; thigh length 12.0, tibia length 12.7; TAL7.1; foot length 12.0. Variation Snout-vent length of adult males 24-27 mm (mean = 25.2; SD = 0.76; N = 74); adult females 24.4-3 1 rnm (mean = 26.9; SD = 1.34; N = 63). In adult females and young the finger fringe is much less developed than in adult males, and the toe fringe is slightly less extensive. The dorsolateral white stripe can be continuous or interrupted, forming small discontinuous spots. Its length also varies in both sexes, extending from the armpit level to groin. The anal region is usually dark olive in females, without the red-copper coloration characteristic of males. The amount of grayish spots on the belly varies according to the sex and locality. In specimens from the type locality, males have few or no ventral spots at all, while several belly spots are present in females. Females from Itariri possess a uniform white belly and males and females from Morro da Boa Vista, have grayish spots on the belly. In specimens from Itariri, the dorsal parts of the body and the limbs have a uniform grayish color, with lighter tones than those observed in frogs from the type locality. In the former the dorsolateral area is also frequently sprinkled with small white spots. In contrast, at Morro da Boa Vista, dorsal parts of arms and legs are more brownish colored and the corresponding ventral part of appendices are yellowish. Larval morphology Description is based on a tadpole in stage 37 (Gosner, 1960) collected at the type locality. Body ovoid in dorsal view, about 1/3 of the total length. Snout truncate; eyes dorsolateral; nostrils circular, directed laterally; weakly developed spiracle sinistral, opening at middle of body; cloaca1 tube short, opening dextral. Oral disc directed ventrally, bordered by an agglomerate of papillae forming two small loops on the sides of the labium, papillae broadly interrupted on the anterior labium; tooth row formula 2(2)/3(1); jaw sheaths strongly developed and serrate, with an indented inferior projection in the anterior jaw, posterior jaw sheath almost right angle-shaped. Length of tail about twice of the body; tail musculature very developed, with low fins; tail higher than body, dorsal fin slightly higher than ventral, tail narrowing fiom the middle towards end. Body dark brown; fiom above a light middorsal area, containing scattered dark spots, extending from the base to the middle of tail; in lateral view, dark chestnut pigments on the anterior part of tail defining a longitudinal stripe extending fiom above musculature to the middle of the tail. Distal part of tail with large and rounded dark chestnut spots on the musculature, smaller on the membrane. Tadpole Variation: In some individuals, the spots of the distal part of the tail are replaced by a blackened uniform coloration, not reaching the extremity of the unpigmented tail. In most of the tadpoles collected at Morro da Boa Vista, this last pattern is accentuated and black pigmentation is more intense in the younger tadpoles, becoming progressively lighter during their development.

Africa

DD. Data Deficient.

Hylodes dactylocinus is a species of frog in the family Hylodidae. It is endemic to Serra do Itatins, in the São Paulo state, southeastern Brazil.