Rhampholeon (Rhinodigitum) nebulauctor, Branch, William R., Bayliss, Julian & Tolley, Krystal A., 2014

Branch, William R., Bayliss, Julian & Tolley, Krystal A., 2014, Pygmy chameleons of the Rhampholeon platyceps compex (Squamata: Chamaeleonidae): Description of four new species from isolated ‘ sky islands’ of northern Mozambique, Zootaxa 3814 (1), pp. 1-36 : 22-24

Rhampholeon (Rhinodigitum) nebulauctor sp. nov.

Mount Chiperone Pygmy Chameleon

Synonomy: Rhampholeon champmanorum (sic.) Timberlake et al. 2007, p20.

Etymology. The specific epithet is a noun in apposition and derived from nebula (L. = cloud, mist) and auctor (L. = maker), i.e. ‘cloudmaker’, alluding to the ‘Ciperoni’, the local name for the cold drizzle that comes to the Shire Highlands of southern Malawi as moist air from the Indian Ocean is forced to rise over Mt. Chiperone.

Types. The type series comprises five specimens, including:

Holotype.- An adult female ( PEM R17278) collected by J. Bayliss, 1 December 2008, in the shrub understorey of evergreen forest on the southeast slopes of Mt. Chiperone Massif, Zambézia Province, Mozambique (16˚30'25.9”S, 35˚43'33.4”E, ca 1000 m a.s.l.).

Allotype. An adult male ( PEM R17281), collected by J. Bayliss on 27 November 2008; same locality details as holotype.

Paratypes. Three specimens, comprising an adult female ( PEM R17277) and two subadult females ( PEM R17279-80), all collected by J. Bayliss between 26 November and 3 December 2008, same locality details as holotype.

Meristics. Measurements for the type series of Rhampholeon nebulauctor sp. nov. are summarized in Table 7 .

Diagnosis. The Chiperone Pygmy Chameleon is referable to the Rhampholeon (subgenus Rhinodigitum Matthee et al. 2004) by having an unpigmented parietal peritoneum, claws that are strongly bicuspid, smooth plantar surfaces, a rostral process, and short tail (<27% of total length in adult males). It can be distinguished from most other species in Rhampholeon (Rhinodigitum) by having deep inguinal (absent or indistinct in Rh. boulengeri , Rh. nchisiensis , Rh. uluguruensis , and Rh. moyeri ) and axillary pits (also absent in Rh. nchisiensis ). It is geographically closest to Rh. chapmanorum , but differs from that species by its smaller size, the presence of a relatively large rostral process in males, and accessory planter spines that are very poorly developed in both sexes. It is well differentiated from Rh. platyceps and Rh. maspictus sp. nov. by its smaller size (SVL <53 mm), relatively larger rostral process, and weakly developed dorsal crest crenulation. It is morphologically closest to the Mt Namuli chameleon, but has a slightly narrower head and appears to lack the cranial flexure of the head present in male chameleons from Mt Namuli (further material is required to confirm both these features). The female holotype also displayed a bright green and orange coloration ( Fig. 7 A, B), but whether this is diagnostic also awaits the collection of further material. Finally, the species is genetically well differentiated from all other Rhampholeon , and all chameleons examined from Mt. Chiperone form a monophyletic clade.

Description of Holotype. Adult female, viscera exposed by a large ventral incision.

Head: Dorsum flattened, with no upward flexure of the snout; casque flat, edged with weakly-defined lateral crests that are mainly restricted to the posterior region of the casque; temporal crest weakly-developed, comprising a single, interrupted row of large tubercles; parietal crest almost absent, composed of a few enlarged tubercles in the mid-line; supraorbital ridges reduced to a few scattered enlarged scales but with a very small multi-scaled process forming a ‘soft horn’ at each end of the inter-orbital ridge that passes across crown and is composed of 11 small granular tubercles, and that demarcate the posterior edge of a slight frontal depression; inferior orbital rim with 4 (right) and 4 (left) enlarged tubercles; snout bordered on each side by moderately developed rostral crests, that fuse together at the tip of the snout which is adorned with a very small, flattened rostral process (1.5 mm), and is three small tubercular scales long and three tubercular scales wide at its base; nares opening posterio-ventrally; no gular or mental appendages; scales on throat homogenous, more conical but smaller than those on crown of head and subequal in size to those on the belly.

Body: Dorsal crest very weakly developed, reduced to 7 crenulations of enlarged, but not obviously spinose scales; crenulations most strongly developed over mid-body, reduced in size over on neck and tail; crenulations continue onto tail but in more reduced form; deep axillary and inguinal pits are present; flank scalation heterogeneous, composed of small, stellate granules with few scattered, enlarged spinose tubercles, the largest at the shoulder and in a single cluster; chest, belly and lower surface of tail smooth; limb scalation more tubercular, with a few enlarged, spinose tubercles on the forearms; claws strongly bicuspid; accessory planter spines on the soles of the fore and hind feet are present, but reduced to a few very small, soft, spinose scales at the base of the claws; tail flattened laterally, flexing slightly downward on the distal third.

Colour in life ( Fig. 7 A, B): Mid-body mottled brown with two vague oblique lateral stripes; fore-body, neck, head and upper surfaces of limbs with extensive bright green tubercles, with scattered light blue tubercles on temporal region of head and throat and on front of belly; scales around orbit dark blue, with a red rim to the iris; tip of casque and dorsal crest cream; enlarged scales of the dorsal crest crenulations orange, that is more extensive and intense along the top of the tail.

Colour in preservative. Body mottled brown with no obvious lateral stripes; lower surface of neck, belly, base of tail, soles of feet, and lower limbs pale brown, except on throat and sides of head which are dark brown.

Description of Allotype (as for holotype, unless noted): adult male, very large ventral incision; hemipenes not everted.

Head: Supraorbital ridge reduced to a few scattered enlarged scales but with a distinct multi-scaled process forming a ‘soft horn’ at the end of the inter-orbital crest that is slightly more pronounced than in female holotype; interorbital ridge, shallow and composed of 12 small granular tubercles; rostral process six tubercular scales long and five wide at base.

Body: Dorsal crest very weakly developed, reduced to eight crenulations of enlarged but not obviously spinose scales, which are subequal in development to those of the female holotype; tail relatively long (26.5% SVL), with a prominent hemipenal bulge; distal third of tail flexes strongly downward.

Colour in preservative: Body mottled brown with no obvious lateral stripes on the flanks. Pale brown below.

Paratype variation. In the largest female paratype (PEM R17277) the ‘horn’ on the supraorbital ridge is reduced to a very small cluster of about 5 spinose tubercular scales; rostral process is very small, 3 scales long and 4 wide at base.

Size. Presumably a small species, as all except the smallest female were reproductively active. Largest male—PEM R17281 (allotype) 32.3 + 11.6 = 43.9 mm; largest female—PEM R17277 (paratype) 48.9 + 13.2 = 62.1 mm.

Reproduction. The three adult females contain enlarged ova, albeit without signs of embryonic development: PEM R17277, Four ova ca. 3.4 mm dia.; PEM R17278, three ova largest measuring 5.0 mm x 3.5 mm; PEM R17279, two small ova (ca. 3.1 mm dia.). The smallest female, PEM R17280, has small developing follicles. The only male (PEM R17281) has well-developed testes despite its small size (32.3 mm SVL).

Distribution. Restricted to the type locality; Mt. Chiperone, Zambézia Province, northern Mozambique.

Habitat. The Chiperone Massif shows habitat zonation and is surrounded by Brachystegia woodland at the base. Chameleons were found on the southeast side of the mountain at 1000 m in wet forest dominated by Khaya anthotheca, Strombosia schefflerii, Rawsonia burtt-davyi, and Drypetes arguta ( Fig. 7 C.)

Figures

FIGURE 7. Rhampholeon nebulauctor sp. nov. Holotype (PEM R 17278): whole body (A) and close-up of head (B); C—Habitat on Mt. Chiperone (J. Bayliss).

Tables

TABLE 7. Measurements (mm) for the type series of Rhampholeon nebulauctor sp. nov. from Mount Chiperone, Mozambique (PEM: Port Elizabeth Museum).

Sex	PEM R17278 Holotype F	PEM R17281 Allotype M	PEM R17277 Paratype F	PEM R17279 Paratype F	PEM R17280 Paratype F
Snout-vent length Tail length Total length	44.7 11.3 56.0	32.3 11.6 43.9	48.9 13.2 62.1	41.6 9.1 50.6	36.3 8.6 44.9
Head length Head width Orbit diameter	14.4 7.4 4.0	10.9 5.9 3.4	14.8 8.9 4.4	13.4 7.2 3.5	12.3 5.8 3.6
Snout length Inter-orbital Rostral process	4.9 5.3 1.5	3.1 4.9 2.2	4.6 5.7 1.4	4.5 5.1 1.3	3.9 4.4 1.1
Casque to Eye	10.2	8.0	10.6	7.2	7.5