Hyperolius inyangae, Channing, A., Hillers, A., Lötters, S., Rödel, O., Schick, S., Conradie, W., Rödder, D., Wagner, P., Dehling, J. M., Du Preez, L. H., Kielgast, J. & Burger, M., 2013

Channing, A., Hillers, A., Lötters, S., Rödel, O., Schick, S., Conradie, W., Rödder, D., Wagner, P., Dehling, J. M., Du Preez, L. H., Kielgast, J. & Burger, M., 2013, Taxonomy of the super-cryptic Hyperolius nasutus group of long reed frogs of Africa (Anura: Hyperoliidae), with descriptions of six new species, Zootaxa 3620 (3), pp. 301-350 : 326-327

Hyperolius inyangae sp. nov. Channing

Nyanga Long Reed Frog ( Fig. 12 )

Holotype. ZMB 77276, a male, collected at Rhodes Dam in the Nyanga National Park, Zimbabwe, 18°17'20.3" S, 32°43'24.4" E, 14 November 2009.

Paratypes. A female, ZMB 77277, and two males, ZMB 77278–9, with the same collecting details as the holotype.

Genetic material. ZMB 77277–8, ZMB 77276 (Rhodes Dam, Nyanga National Park, Zimbabwe); ZMB 76099-101 (Kaningina, Malawi).

Diagnosis: The advertisement call ( Fig. 10 ) consists of a brief initial note of four pulses, followed by nine slower pulses, with a duration of 0.35 s. It can be distinguished from species producing only a single note, and those producing only a buzz: H. acuticeps , H. adspersus , H. dartevellei , H. jacobseni sp. nov., H. lupiroensis sp. nov., and H. nasutus . It can be distinguished from those species with short calls under 0.2 s: H. friedemanni , H. howelli , H. igbettensis , H. poweri and H. rwandae sp. nov. It differs from H. viridis , which has an initial note consisting of 26 pulses. See Table 3 for a summary of call parameters. It has a shark-like snout profile, which distinguishes it from those species that have truncated or rounded snouts; H. acuticeps , H. adspersus , H. dartevellei , H. friedemanni , H. igbettensis , H. jacobseni sp. nov., H. lupiroensis sp. nov., H. nasutus , H. poweri , H. rwandae sp. nov., and H. viridis . The webbing is characterized by three phalanges free of the fourth toe, and two phalanges free of the fifth toe. This distinguishes it from all other species (which have more webbing).

Description of Holotype. Body long and slender, widest at mid-body, slightly tapering to groin; head comparatively small (HL/SUL 0.37, HW/SUL 0.29), not wider than trunk, longer than wide (HL/HW 1.27); snout long (SL/HL 0.46), sharply rounded in dorsal view, acute in profile with a distinct protruding tip ( Fig. 6 ), considerably projecting beyond lower jaw, wider than long (SL/EE 0.82); canthus rostralis distinct, sharp, almost straight-lined from eye to nostril, slightly convex near tip of snout; loreal region almost vertical, slightly concave; nostril directed dorsolaterally; situated midway between tip of snout and eye (EN/NS 1.0), separated from each other by distance greater than distance between eye and nostril (NN/EN 1.15); eyes directed anterolaterally, moderately protruding, relatively small (ED/HL 0.23); eye diameter shorter than snout (ED/SL 0.51); interorbital distance much wider than upper eyelid (IO/EW 1.14), and greater than internarial distance (IO/NN 1.04); tympanum not visible externally; upper jaw with dentition; teeth on premaxilla larger than those on maxilla; choanae small, slightly oval, located far anterolaterally at margins of roof of the mouth; vomer processes and teeth absent; tongue long 4.6, and narrow (2.9 at widest point), free for about one-quarter of length, bifurcated distally for about one-fourth of length; median lingual process absent; vocal sac single, median, subgular, mostly unpigmented and translucent when fully inflated; gular flap consisting of thickened granular skin, vocal sac aperture on each side of the mouth, situated lateral from and close to base of tongue, slit-like, long, directed posterolaterally.

Dorsal surfaces of head, trunk and limbs finely granular with minute tubercles visible under magnification; ventral surface of limbs and gular smooth, chin and abdomen slightly more areolate.

Fore limbs slender; hand moderately large (HND/SUL 0.24); tips of fingers enlarged into broad oval disks, each with circummarginal groove; relative length of fingers: I<II<IV<III; subarticular tubercles rounded, well developed, with one on fingers I and II, two on fingers III and IV, with proximal tubercle on finger IV hardly discernible; webbing formula of the hand I 2 +– 2 II 2– 3 III 2.5–2.5 IV (after Myers & Duellman [1982]); thenar tubercle absent; palmar tubercles absent; metacarpals without supernumerary tubercles; nuptial pads or asperities absent.

Hind limbs slender, moderately long (LEG/SUL 1.42); tibio-tarsal articulation not reaching to level of tip of snout when legs are adpressed to body; tibiofibula moderately long (TFL/SUL 0.48), subequal to thigh (TFL/THL 0.97); heels overlapping each other considerably when knees are flexed and thighs are held laterally at right angle to body; foot shorter than tibiofibula (FOT/TFL 0.85); relative length of toes: I<II<III<V<IV; discs of toes smaller than those of fingers; subarticular tubercles: one on toes I and II, two on toes III and V, and three on toe IV; pedal webbing formula ( Fig. 7 ) I 1.5–1.5 II 0.75– 2 III 1.5– 3 IV 3– 2 V; inner metatarsal tubercle absent; outer one almost circular, flattened.

Colouration in life. head green, overlain with brown pigment which extends over the back and exposed surfaces of limbs. Tibia reddish-brown. Iris and eyelid pale brown. The vocal sac is pale green. Colouration in preservative. a yellow-brown background, covered dorsally with a dense speckling of small black and brown melanophores and chromatophores. No pale lateral stripes, pigmentation over snout and head more dense than dorsum. Upper exposed surfaces of limbs and digits pigmented.

Paratype variation. The paratypes are similar to the holotype in measurements (Appendix 2). The two males are similar in proportions, including the sharp protruding snout tip, but both have pale lateral stripes. The female, 21.6 SUL, is gravid, with a mid-body width of 10.2. The female also has a sharp shark-like snout, although it is not as acute as those of the males.

Eggs and tadpoles. A female (ZMB 77277) has enlarged ovarian eggs with a diameter of ca. 1.3. Eggs are darkly pigmented on the animal pole and white on the vegetative pole. Tadpoles are unknown.

Etymology. The species is named for the Nyanga National Park, Zimbabwe.

Remarks. The species is known from the Eastern Highlands of Zimbabwe and northern Malawi. The distribution of this species appears to cover at least 900 km of highlands between the collecting localities. Due to the extensive range we suggest that this species be regarded as Least Concern in terms of the IUCN criteria.

Figures

FIGURE 6. Snout profiles of representatives of the species in the Hyperolius nasutus group.

FIGURE 7. Webbing diagrams of representatives of the species in the Hyperolius nasutus group.

FIGURE 10. Advertisement calls of H. howelli Arusha (left), H. igbettensis Comoé National Park, Ivory Coast (center) and H. inyangae Rhodes Dam (right).

FIGURE 12. Hyperolius igbettensis, Lamto, Ivory Coast, photo M. - O. Rödel (A); Hyperolius jacobseni sp. nov. holotype, ZMB 77280, Gatiko, Central African Republic, photo N. Jacobsen (B); Hyperolius inyangae sp. nov. male holotype, ZMB 77276, Rhodes Dam, Nyanga National Park, Zimbabwe, photo A. Channing (C); female paratype H. inyangae, ZMB 77277, same details (D); Hyperolius nasicus, Nyanga Flats, Zimbabwe, photo A. Channing (E); H. lamottei, night pattern, Mt Nimba, Guinea, photo M. - O. Rödel (F); Hyperolius lupiroensis sp. nov., holotype ZMB 77300, Lupiro, Tanzania, photo A. Channing (G).