Agama caudospinosa spawlsi, Wagner, Philipp, 2010

Wagner, Philipp, 2010, Studies on African Agama VIII. A new subspecies of Agama caudospinosa Meek, 1910 (Sauria: Agamidae), Zootaxa 2715, pp. 36-44 : 37-40

Agama caudospinosa spawlsi ssp. n.

Holotype. ZFMK 83666, adult male from Nkunga (00°06’73N, 37°35’77E), north of Meru, leg. A. Burmann, 01.IV.2005.

Paratypes. ZFMK 83664, subadult from Nkunga, north of Meru, leg. A. Burmann, 01.IV.2005. ZFMK 83665, juvenile from Nkunga, north of Meru, leg. A. Burmann, 01.IV.2005. ZFMK 83667, adult male from Kiamatongu (00°19’02S, 36°54’04E), leg. A. Burmann, 04.IV.2005. ZFMK 83661-663, subadult males and juvenile from Naru Moru (00°11’92S, 37°04’76E), leg. A. Burmann, 28.III.2005.

Diagnosis. The new subspecies is characterized by possessing only a slight sexual colour dimorphism (see fig. 1), which is very rare in African Agama species, and by a bright orange ventral colouration in nuptial males. It differs from all other East African Agama species (apart from A. mwanzae and A. kaimosae ) in the possession of a large and flat body, a broad and muscular tail base, smooth body scales, unique colouration (see below) and the slightly evolved colour dimorphism between the sexes. It differs from the similar A. mwanzae and A. kaimosae by the flattened body and tail base and the colouration. A. mwanzae has a pinkish head and red and blue body; A. kaimosae an orange head and coloured back. The new subspecies differs from the nominate subspecies by possessing a different colouration (see below), in a higher mean count of scale rows around midbody (A. c. caudospinosa : 84, A. c. spawlsi : 96, see table 1) and in its genetic distance (see Wagner et al. in prep.).

Topotypical adult individuals (fig. 1) of the nominate subspecies A. c. caudospinosa are characterized as follows: males (a) head grey-black, with an orange lateral stripe and an orange framed ear opening; neck pale orange with whitish spots, throat orange, with few dark stripes; (b) body grey-black with light blue coloured scales close to the pelvic area, chest and belly grey-black; and (c) tail banded grey-black and whitish. Females: (a) head brownish, neck grey-brown with four whitish dots, throat beige with longitudinal stripes; (b) body brown with a dark pattern of latitudinal stripes and dark framed pale dots, belly beige laterally orange; and (c) tail banded brown and whitish.

The new subspecies (fig. 1) differs from the nominotypic subspecies in the possession of the following characteristic colouration: males (a) head grey-brown with an orange lateral stripe and an orange framed ear opening, neck orange without dots, throat and chest deep orange; (b) body dorsally brown with whitish dots at the pelvic, laterally orange, forepart of the belly orange becoming brownish towards the tail; and (c) tail banded brown and whitish. Females; (a) head grey-black, with a white lateral stripe and a white framed ear hole, neck dorsally and laterally orange, throat beige with longitudinal dark stripes; (b) body dorsally grey-black with few pale dots at the pelvic, lateral parts of the body orange; and (c) tail banded gray-black and white.

Colouration (in alcohol after 5 years of preservation). Head above brownish orange, a pale lateral stripe from the nostril along the labial scales to the ear opening is present. Neck dark orange to reddish, on both sides of the neck, a dorsolateral dark framed orange stripe is obvious, from the ear opening to the shoulder, and than to about half length of the body. Throat pale orange, with few dark longitudinal stripes. Forelimbs orange to reddish, hindlimbs bluish-brown with orange-brown parts on the upper tight and pale orange on the lower tight. Dorsal part of the body brownish, with scattered orange scales at the forepart and whitish scales and three stripes at the pelvic area, laterally forepart of the body orange, hindpart brownish. Forepart of the belly orange becoming bluish towards the pelvic. Tail above banded dirty orange and brownish orange, dirty white on the underside.

Variation. For differences in measurements and scale counts of the new subspecies see table 1. Live colouration of males is very similar but often the dorsal parts of the body are a mixture of orange and brown. In preservation the orange colouration often disappears; thus in some of the paratypes the belly is uniform dirty white. Females vary slightly within the pattern described of the new subspecies. Subadult males resemble in pattern the adult males, but without orange colouration. Juveniles posses a typical colouration which is different to adult individuals: a uniform brownish body with darker latitudinal stripes between the limbs and mottled with dark framed yellowish dots and stripes. For differences in colouration between adult males of the two subspecies and a juvenile of the new subspecies see fig. 3.

Description of the holotype (fig. 2). Habitus stout, body and head flattened, tail base broad, flat and muscular; snout-vent length 115.3 mm; tail length 109.7 mm, but tip of the tail broken; head length 33.1 mm, head with 25.1 mm, head height 13.0 mm. Large triangular nasal scale on the canthus rostralis and pierced with a large nostril in the posterior part, directed and angled obliquely side- and upwards. Between the nasal scales, two narrow longitudinal, smooth scales are visible, anterior smaller than posterior, the posterior is followed by one smooth transverse scale, which is followed by two parallel scales of same shape and size, all of the scales larger than the surrounding head scales. 12 supralabial scales on the left, 13 on the right side, 10 sublabial scales on both sides. Head scales smooth, slightlx imbricate, only few of them with free anterior margins which have numerous sensory pits; supraocular scales smooth. Parietal shield elongated pentagon, pineal organ visible, pierced in the posterior part of the shield; parietal shield surrounded by scales more or less equal in size. Ear opening large, about the same size as the eye, margin being framed by spiny and mucronate scales, few of the groups in two tufts at the posterior part of the ear opening; tympanum superficial. Nuchal crest absent, only a group of few spiny and mucronate scales present. Gular scales flat, smooth, juxtaposed and becoming smaller towards the gular fold. Dorsal body scales smooth, equal in size, 69 scales from midpoint of pectoral region to midpoint of pelvic region. Ventral body scales smooth, slightly imbricate at their posterior margins, in 78 scales from midpoint of pectoral region to midpoint of pelvic region. There are 96 scales rows around midbody. One row of 11 precloacal scales, but a second row of two scales is present. Tail scales smooth but mucronate, on the tail base, only lateral parts with mucronate scales, dorsal scales feebly keeled and ventral scales smooth. Scales on the upper- und underside of the forelimb smooth, on the upper arm scales thrice as large as the dorsal body scales, becoming slightly smaller towards the underside and the manus. 4th finger longest, digital length decreasing 3-2-5-1, subdigital lamellae keeled and mucronate. Scales on the upper side of the hindlimb smooth to feebly keeled becoming strongly keeled on the underside, on the upper tights slightly larger as the dorsal body scales becoming much larger towards the lower tights. 4th toe longest, digital length decreasing 3-2-5-1.

SVL: snout-vent-length; HL: head length; HH: head height; HW: head width; MS: number of scale rows around midbody; DS: dorsal scales; VS: ventral scales; CP: cloacal pores.

Etymology. This new subspecies is dedicated to Stephen Spawls, Norwich ( England) in recognition of his important contributions over many decades to the herpetology of East Africa.

Molecular evidence. According to Wagner et al. (in prep.) DNA isolation, PCR, aligning and phylogenetic analysis were done as described by Wagner et al. (2009). The analysis of 500 base pairs of the 16S rRNA gene revealed that A. caudospinosa spawlsi ssp. n. is monophyletic and sister taxa to the nominate subspecies. The genetic distance (uncorrected p-distance) between A. caudospinosa spawlsi ssp. n. and A. c. caudospinosa is slightly more than 2.0% for the 16S rRNA gene.

Distribution. The new subspecies is at present only known from the vicinity of Mount Kenya and the Kerio Valley and is recorded from the following localities: Kiamatongu, Naro Moru, Meru (all near Mt. Kenya) and Iten in the Kerio Valley.

Ecology. The ecology of the new subspecies is currently unknown but is probably similar to the nominate form. It is diurnal, rock living, territorial, egg-laying and feeds on various arthropods. In areas with rocky outcrops it will utilise any rock surfaces, but it will also live in open savanna and grassland provided there are a few exposed rock patches in which to hide and some boulders – even small ones – for the males to bask on.

Conservation. Following the criteria of the IUCN (2001) A. caudospinosa , including both subspecies, should be protected as endangered. The species has an extent of occurrence less than 5,000 km 2 and seems to occur in fragmented populations. This should aid with conservation efforts, especially since agamids might be popular in the pet trade.