Mahogany Frog

Diagnosis. Body robust, medium-sized; head moderate; snout short, rounded, canthus rostralis smoothly rounded; interorbital space broader than the upper eyelid; tympanum distinct, not quite two-thirds the size of the eye with no pale colouration on the margins of the tympanum; no vocal sacs in males; vomerine teeth in two small oblique patches on a level with the posterior edge of the choanae; length of 1 st finger greater than 2 nd finger; disc width to finger width ratios of finger 3 and toe 4 is 1 - 1.5; dorsolateral fold indistinct or absent; the humeral gland in males is prominent, raised and centrally positioned on the ventral surface of the upper arm; a weak or absent rictal ridge; outer metatarsal tubercle weak or absent; subarticular tubercles moderate; skin of dorsum smooth or finely shagreened; throat, abdomen, and flanks smooth; posterior section of venter and back of the thigh rugose; dorsum reddish-orange to chocolate-brown, encircled by a white or cream coloured dorsolateral line that encircles the snout, canthus rostralis, outer edge of the upper eyelids, and dorsum along the dorsolateral fold to the vent; lower flanks dark-brown or black below the dorsolateral line grading into a paler venter; dorsal colouration of the limbs same as the flanks with whitish or light-grey speckles or stripes. Abavorana luctuosa can be easily differentiated from its congeners on the basis of its ventral colour pattern which is usually immaculate or with only very faint, sparse, light speckling (Figs 3, 4, 9 A-B). Adult males with SVL 35.05 - 44.27 mm, adult females with SVL 37.05 - 51.06 mm; adult males with SW 7.11 - 8.62 mm, adult females with SW 7.65 - 9.38 mm; adult males with IOD 3.25 - 5.14 mm, adult females with IOD 3.80 - 5.64 mm; adult males with TD 2.50 - 3.83 mm, adult females with TD 2.95 - 4.24 mm; adult males with FL 17.81 - 22.04 mm, adult females with FL 19.13 - 26.37 mm (Table 5).