Phrynocephalus arabicus ANDERSON, 1894
|Higher Taxa||Agamidae (Agaminae), Sauria (lizards)|
|Common Names||Arabian Toadhead Agama|
|Synonym||Phrynocephalus arabicus ANDERSON 1894: 377|
Phrynocephalus arabicus — HAAS 1957: 67
Phrynocephalus nejdensis HAAS 1957: 68
Phrynocephalus nejdensis macropeltis HAAS 1957: 69
Phrynocephalus arabicus — WERMUTH 1967: 76
Phrynocephalus arabicus — BISCHOFF & SCHMIDTLER 1981
Phrynocephalus arabicus — BARTS & WILMS 2003
Phrynocephalus arabicus — SINDACO & JEREMČENKO 2008
Phrynocephalus nejdensis — MELNIKOV et al. 2014
Phrynocephalus arabicus — MELNIKOV et al. 2014
Phrynocephalus macropeltis — MELNIKOV et al. 2014
|Distribution||SE Saudi Arabia, United Arab Emirates, Oman, Iran, S Iraq ?, Jordan|
Type locality: Plateau of Hadramut, SE Arabia.
nejdensis: Type locality: "Nafud, near Qana, North Nejd, WNW of Hail, Saudi Arabia".
macropeltis: Type locality: "Dhahran [Az Zahrãn], Saudi Arabia" [approximately 26º17' N, 50º12' E]. Map legend:
- Type locality.
- Region according to the TDWG standard, not a precise distribution map.
NOTE: TDWG regions are generated automatically from the text in the distribution field and not in every cases it works well. We are working on it.
|Types||Syntypes: BMNH 19220.127.116.11 (formerly BMNH 18.104.22.168) and BMNH 1922.214.171.124 (formerly BMNH 126.96.36.199).|
Holotype: CAS 84619 [macropeltis]
Holotype: HUJ 2711 [nejdensis]
|Comment||Synonymy: partly after LEVITON & ANDERSON 1967. Note that Melnikov et al. 2014 split P. arabicus into 4 species: arabicus, nejdensis, macropeltis, and ahvazicus. The description of Melnivkov is quite confusing, so we postpone to make these changes for the time being. For instance, in the text they mention that they studied 108 specimens of P. arabicus s. l. but show only 15 localities in their map (fig. 1). Also, the map says “tissue samples” but doesn’t say of what.|
Phrynocephalus arabicus sensu stricto is characterized well by the very contrasting coloration of the upper side of the body (Figs. 3e and 4d ). Background is bluish gray with bright dark orange-red pattern on the head, two bright orange stripes on the neck, two longitudinal rows of six bright orange (salmon) patches on the back, and dark orange-red on the sides of the body, joined to form a transverse bright pattern with clear middorsal line, similar smaller patches are on the tail, forming transverse pattern (Fig. 3e). This pattern was mentioned in the J. Arnold original description, but due to preservation is not present in the type specimens now (Fig. 2a). But the main character of Ph. arabicus sensu stricto is the unique tail coloration, as this species has white coloration of the undertail and only the tail tip (last quarter) has very small black bands. In the type specimens two and three small bands on the tail tip are present (Fig. 2a) and in the specimens from Oman only two small black bands (Figs. 4c and 5c). Probably in alerted animals the whole last quarter of the tail becomes totally black. This species is characterized also by pointed snout and relatively long tail (Table 1). [MELNIKOV et al. 2014]
Phrynocephalus nejdensis is also characterized by special coloration of the dorsal side of the body and undertail. This species does not have bright color marks on the dorsal side. General coloration is in one color tone, with contrasting yellow-brown or yellow-reddish-orange with dark-brownish transverse bands (Fig. 3c, d and 4a – c). Upper side of the head has the same pattern and color as body. White dots on the middorsal line can be distinguished, with some individuals appearing as a longitudinal row along the vertebrae. This species is also well characterized by many black transverse tail bands (up to seven), that cover about half of the undertail in the calm condition of the animal (Fig. 4c). These bands sometimes are not well distinguished in alerted individuals, especially in males, as whole distal half of the tail became black and bands became just slightly visible, but the additional bands in the proximal half of the tail appear (Fig. 5b ). The black tail coloration of the alerted animal is recognizable even on the upper side of the tail, while in calm condition it is whitish. In the Holotype there are two additional bands on the proximal half of the tail and a totally black distal half (Fig. 2b ). This is the biggest and most short-tailed species — the tail almost the same length as body even in males (Table 1). [MELNIKOV et al. 2014]
Phrynocephalus macropeltis is characterized by intermediate morphological characters between Ph. arabicus sensu stricto and Ph. nejdensis, which needs further investigation, due to probable hybridization between these species. The diagnostic characters proposed by G. Haas (1957) for this subspecies were similar to those of Ph. arabicus sensu stricto. For Ph. nejdensis he stated that it differs from Ph. arabicus in: small size of gular scales, smaller ventrals and proximal subcaudals, higher number of upper and lower labials, and flatness of the dorsal head scales. But Ph. nejdensis macropeltis differs from Ph. nejdensis nejdensis in some opposite characters: larger ventral scales, head scales more bulging, and some of the pectoral scales keeled (Haas, 1957). In other words, G. Haas mixed the difference between his species Ph. nejdensis and Ph. arabicus by describing the subspecies Ph. n. macropeltis which differs from Ph. nejdensis in opposite characters which distinguish Ph. nejdensis from Ph. arabicus. Probably because of that, Leviton and Anderson (1967) showed that differences of Ph. nejdensis and Ph. n. macropeltis from Ph. arabicus was “illusory,” and that all meristic characters are overlapping in the populations they studied. As for diagnostic characters proposed by us, Haas (1957) mentioned for Ph. nejdensis — “posterior half of the tail blackish, with faint darker cross-bands” (Holotype also have additional bands in the proximal half of the tail (Fig. 2b )), but for Ph. n. macropeltis — “last third of the tail is black below” (Fig. 2c). All studied specimens from the coastal eastern Arabia (eastern Saudi Arabia and UAE) are characterized by black last third of the tail and no additional cross bands on the rest of the undertail and this is useful taxonomic character for them. To access the living dorsal coloration of Ph. n. macropeltis more material is needed, but it seems similar to those of Ph. nejdensis (Fig. 3g ). Body and tail proportions also similar to Ph. nejdensis (Table 1). [MELNIKOV et al. 2014]