Rhampholeon (Rhinodigitum) maspictus, 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 : 17-22

Rhampholeon (Rhinodigitum) maspictus sp. nov.

Mount Mabu Pygmy Chameleon

Synonomy: Rhampholeon (Rhinodigitum) chapmanorum Tilbury 2010 , p 179.

Rhampholeon sp. Timberlake et al. 2012, p 45; Bayliss et al. 2014, p 179.

Etymology. The specific epithet derives from a combination of mas (L. = man) and pictus (L. = painted), alluding to the unusual bright colours of most males, which are often retained for long periods, even when sleeping at night.

Types. The type series comprises ten specimens all preserved in 50% propanol (except for one hatchling in 90% ethanol), including:

Holotype. An adult male ( PEM R18072; Fig. 5 A, 6A) collected by a W.R. Branch, J. Bayliss & W. Conradie, 27 May 2009, in the vicinity of the main forest base camp, Mt. Mabu, Zambézia Province, Mozambique (16º17'10.1"S, 36º24'02.2"E; 967 m a.s.l.).

Allotype. An adult female with a small ventral incision ( PEM R18061, Fig. 5 B, 5A), same collecting details as holotype.

Paratypes. Eight specimens, comprising four males ( PEM R18059, 18073 ( Fig. 6 B), 18074-75), same collecting details as holotype; three females ( PEM R18069-70, 18076), same collecting details as holotype; and a hatchling ( PEM R18068, Fig. 6 C)

Additional material (used in analysis but not forming part of the type series): 13 specimens, all from forest Camp region, Mt. Mabu, Zambezia Province, Mozambique (16˚17'12"S, 36˚24'14"E; 1000m a.s.l.); PEM R17130 (J. Bayliss, January 2006), PEM R17911-12 (J. Bayliss, 16 April 2009), PEM R18057-58, 18060, 18062-67, 18071, same collecting details as holotype.

Meristics. Measurements for the type series of Rhampholeon maspictus sp. nov. are summarized in Table 6 .

Diagnosis. The Mt. Mabu Pygmy Chameleon is referable to the Rhampholeon (subgenus Rhinodigitum Matthee et al. 2004) by possessing a short hemipenis that is almost bag-like, acalyculate and adorned with a pair of simple, curved apical “horns” with a variable number of thorn-like papillae arranged on the outer aspect of the horn; claws that are strongly bicuspid, smooth plantar surfaces, a rostral process, and short tail (<25% 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 differs from all other members of the Rh. platyceps complex by the bright green male breeding coloration, including blue flanks and side of head, and yellow throat, snout and eye ring (all of which may be retained even at night). It shares with Rh. platyceps , but differs from all other populations of the complex from Mt Chiperone, Mt Namuli and Mt Inago, its large size (> 60 mm SVL) in both sexes, lack of male dwarfism, well-developed dorsal crenulations, and reduced rostral and supraocular processes; it differs from Rh. platyceps by its more dorsoventrally flattened habitus (more rounded in Rh. platyceps ), and very weak or even absent accessory plantar spines (present but small in Rh. platyceps ). Finally, the species is also genetically well differentiated from all other Rhampholeon , and all chameleons examined from Mt. Mabu form a monophyletic clade.

Description of Holotype. Adult male, viscera exposed by a single ventral incision in the chest region; both hemipenes everted.

Head: Dorsum of head flattened, with no upward flexure of the snout; casque flat with weakly define lateral crests; temporal crest moderate with a single row of interrupted large tubercles; parietal crest almost absent, composed of a few enlarged tubercles in the mid-line; supraorbital ridge present but with only few raised conical tubercles; three enlarged tubercles on inferior orbital rim; supraorbital connected in middle by shallow interorbital ridge composed of 11 small granular tubercles that demarcate the posterior edge of a prominent frontal depression; rostral ridge very well marked, forming a small bump over the nostrils and fusing anteriorly and adorned with a small rostral process (2.1 mm, in fixation flattened against rostrum); rostral process 4 small tubercular scales long and 4 tubercles wide at base; nares opening posterio-ventrally; no gular or mental appendages; scales on throat homogenous, more conical than those on crown of head and subequal in size to those on the belly.

Body: Dorsal crest moderately developed, comprised of 9 weak crenulations each comprised of a cluster of enlarged spinose scales, crenulations most strongly developed over mid-body, reduced over base of neck and tail; crenulations continue onto tail comprised of 9 small groups that are largest over the distal half of the tail; deep axillary and inguinal pits are present; flank scalation heterogeneous, composed of small, stellate granules with scattered, enlarged spinose tubercles, the largest occurring over the shoulder; 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 plantar spines very reduced or almost absent.

Colour in Life: Male coloration stunningly beautiful ( Figs. 5 A); body, tail and limbs leaf green, slightly mottled and also darker along the dorsal crest of body, tail and upper surfaces of fore- and hindlimbs; central region of flanks light blue, with two oblique, broad yellow-green stripes; light blue of flanks extends onto the side of head and around eye, where it becomes darker and more intense; front of chest, throat, labials, rostral process and upper surface of snout to the level of the orbit, dirty yellow; bright yellow eye ring. When stressed (e.g. in artificially close proximity to another chameleon) the body coloration changes dramatically, the body darkening to greenbrown, and the blue flank region becomes paler and infused with brown blotches ( Fig. 6 A); the green orbital region, yellow eye ring and dirty yellow throat colour are retained, albeit in subdued form.

Colour in preservative: Body dark brown with 3 faint oblique bars of lighter brown on flanks running from backbone to lower flank; belly, tail and limbs uniform dark brown, except light brown on inner surface of forelimbs.

Description of Allotype (as for holotype, unless noted): adult female, with viscera exposed by a single, ragged ventral incision in the belly, and liver tissue excised for DNA analysis.

Head: Temporal crest weakly developed comprised of a disrupted row of slightly enlarge tubercles; parietal crest absent; subocular ridge weakly pronounced with few enlarged tubercles; interorbital ridge with 13 weakly enlarged tubercles

Body: Dorsal crest very weakly developed, comprising 7 crenulations of tubercles that are only slightly enlarged; crenulations most strongly developed over mid-body and almost absent on the tail; flank scalation heterogeneous, composed of small, stellate granules with very few scattered, enlarged spinose tubercles, the largest at the shoulder.

Coloration in Life: Less intensely coloured than male holotype ( Figs. 5 B); sides of body dorsally dull green with two vague, oblique, dark olive stripes that extend from dorsal crest, where they are broader, onto lower flank; upper flanks with large, irregular light brown blotches that coalesce and cover upper surface of tail; lower flanks brighter green with scattered pale blotches, extending as pale green onto lower surface of tail; upper surfaces of limbs olive, paler green below; upper surface of casque pale brown, extending at a narrow, almost white line along the dorsal crest; front and sides of snout mottled in light green and brown giving a dull green-brown appearance; throat cream with numerous light blue tubercles that coalesce to form irregular blotches; orbital area olive green with scattered pale blue tubercles and a dull red eye ring. When stressed the irregular light brown blotches on the upper flanks become paler, and the sides of head become blotched, especially in the labial region, giving an appearance of alternating pale and dark bands radiating from the eye ( Fig. 6 A).

Colour in preservative: Body and head uniform dark brown above and below.

Paratype variation. All paratype males have well-everted hemipenes. In life the orbital scalation of a male paratype (R17130) was light green, with a conspicuous yellow ring around the iris; the pale brown body had two prominent rust red “leaf vein” narrow lines that ran from the dorsal crest obliquely to the lower flank; there is a prominent enlarged, pale yellow-cream spinose tubercle on the fore-flank in the shoulder region; the crown of the casque and dorsal crest on the body and tail was medium brown ( Fig. 6 B). A very small specimen (PEM R18068, SVL 19.6 mm) has a mottled reddish brown head, body and limbs, with two vague, narrow oblique red-brown stripes that run from the dorsal crest to the lower flanks; the dorsal crest forms a narrow cream stripe that extends onto the casque, where it becomes disrupted into small blotches; the limbs are darker brown with scattered bright yellow tubercles of the upper surfaces; the orbital region is dull brown with scattered small blue tubercles and a dull red eye ring ( Fig. 6 C).

Size. Largest male—PEM R18074 (paratype) 65.2 + 20.1 = 85.3 mm; largest female—PEM R18069 (paratype) 64.4 + 16.2 = 80.6 mm. The smallest specimen—PEM R18068 (paratype, unsexed) 19.9 + 4.9 = 24.8 mm) appears to be newly hatched.

Sexual Dimorphism. The average total size of males (65.3 mm, n = 11) and females (64.4 mm, n = 11) is similar and suggests no sexual size dimorphism. However, males do have proportionately longer tails (TL as = % of SVL 24.0% in males, but only 18.6% in females). Sexual dichromism in pygmy chameleons remains poorly known, and has not been studied in the Rh. platyceps complex. Tilbury (1992) noted the emergence of bright colours (pale powder blue head and neck, and bright white eyelids) in male Rh. chapmanorum in male-male interactions. The bold colours of large male Rh. maspictus sp. nov. ( Fig. 5 A) was noted in three different males at the type locality, including two specimens sleeping at night on low vegetation. No female was observed showing the bright green body and blue and yellow head of adult males.

Hemipenis. (based on everted hemipenes of five males in the type series). Hemipenis short with unadorned basal and apical sections, except for a pair of curved horns that form the lateral edges of a prominent, flat-topped crown; 3-4 weakly-developed spines occur on the upper surfaces of the horns; the folds of the sulcus spermaticus flare to drain into the flattened apical region.

Distribution. Known only from the type locality; Mt. Mabu, Zambézia Province, central Mozambique, but expected to occur throughout much of the extensive forest (+7880 ha) remaining on the massif ( Bayliss et al. 2014).

Habitat. The Mabu massif is a complex of granitic inselbergs formed of syenite, an igneous intrusion of the younger Precambrian Namarroi series dating from 850 ‒1100 Mya (Instituto Nacional de Geologia 1987). Although the Mabu Massif shows vegetational zonation and a significant extent (+7880 ha) of mid-altitudinal forest, it lacks the large area of upland plateau that occurs on Mt. Namuli. Mt. Mabu is surrounded by Brachystegia woodland at the base, much of which is replaced to the south by the Cha Madal tea estate. The paratype series were collected at night on perches from 30-100 cm above ground in forest clearings and adjacent to a mountain stream ( Fig. 6 D). No specimens were collected on perches as high as 1.3 m to 5 m noted for Rh. chapmanorum ( Tilbury 1992) . This may be related to the presence of an additional chameleon ( N. baylissi ) which utilizes this forest stratum on Mt. Mabu, and that has not been recorded on Mt. Chiperone.

Reproduction. The female allotype was gravid with seven almost spherical eggs (largest diameter 4.1-4.5 mm, four in the left oviduct and three in the right oviduct) that lack obvious signs of embryonic development.

Figures

FIGURE 5. Rhampholeon maspictus sp. nov.: A—Holotype, B—Allotype (W. R. Branch)

FIGURE 6. Rhampholeon maspictus sp. nov.: A—Allotype (left) and Holotype (right); B—Paratype (PEM R 17073); C Paratype (PEM R 17068, hatchling); D—Habitat on Mt. Mabu (W. R. Branch).

Tables

TABLE 6. Measurements (mm) for the type series of Rhampholeon maspictus sp. nov. from Mount Mabu, Mozambique (PEM: Port Elizabeth Museum).

Sex	PEM R18072 Holotype M	PEM R18061 Allotype F	PEM R18059 Paratype M	PEM R18073 Paratype M	PEM R18074 Paratype M
Snout-vent length Tail length Total length	62.0 19.4 81.4	59.0 13.1 72.1	56.2 18.1 74.3	63.4 17.5 80.9	64.4 19.8 84.2
Head length Head width Orbit diameter	19.1 11.1 5.2	18.2 9.8 4.3	20.0 12.3 4.9	19.6 11.7 5.0	20.3 12.1 5.4
Snout length Inter-orbital Rostral process	6.0 5.9 2.1	5.0 4.7 1.2	6.8 5.4 2.1	5.9 5.8 1.9	5.9 5.9 2.7
Casque to Eye	13.3	8.3	8.9	10.6	9.1
TABLE 6. (Continued)
Sex	PEM R18075 Paratype M	PEM R18069 Paratype F	PEM R18070 Paratype F	PEM R18076 Paratype F	PEM R18068 Paratype Hatchling
Snout-vent length Tail length	64.0 16.9	64.8 15.1	61.9 14.0	56.8 11.6	19.6 4.9
Total length Head length Head width Orbit diameter	80.9 18.1 10.4 4.7	79.9 19.3 11.3 4.4	75.9 17.8 10.9 4.2	68.4 18.0 9.3 3.9	24.8 6.9 4.9 2.1
Snout length Inter-orbital	5.5 5.2	6.1 5.7	5.5 5.7	5.4 5.7	2.0 3.3
Rostral process Casque to Eye	2.5 8.7	1.0 9.7	2.3 8.7	1.0 9.3	0.5 2.9