Phrynocephalus persicus

Persian Toad-headed Agama
Phrynocephalus persicus
Conservation status

Critically Endangered  (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Subclass: Lepidosauria
Order: Squamata
Suborder: Sauria
Infraorder: Iguania
Family: Agamidae
Subfamily: Agaminae
Genus: Phrynocephalus
Kaup, 1825
Species: P. persicus
Binomial name
Phrynocephalus persicus persicus
De Filippi (1863)
Synonyms
  • P. persicus horvathi Méhely (1894)
  • P. helioscopus Méhely (1894)

The Persian Toad-headed Agama (Phrynocephalus persicus De Filippi, 1863) is a small diurnal desert lizard of Agamids family. This small predator forages on various small arthropods as ants, spiders, grasshoppers, beetles, bees and flyes, etc. It is the westernmost representative of the Central Asian genus of Toad-headed Agamas Phrynocephalus and is only known from deserts and semideserts of Near Eastern countries of Armenia, Azerbaijan, Iran and E Turkey. There is an ongoing scientific debate about the phylogeny and the taxonomic format of Phrynocephalus persicus. The most recent studies (Melnikov, et al. 2008,[2] Solovyova et al. 2011[3]) suggest existence of at least two distinct forms (subspecies, which are Persian Toad-Headed Agama (Phrynocephalus persicus persicus De Filippi, 1863) from the Northern and Central Iran and Horvath's Toad-Headed Agama (Phrynocephalus persicus horvathi Mehely, 1894) from Armenia, Azerbaijan, NW Iran and NE Turkey. The International Union for Conservation of Nature considers Phrynocephalus persicus and Phrynocephalus horvathi as two distinct species: the Persian Toad Headed Agama (Phrynocephalus persicus) is Vulnerable,[4] while Phrynocephalus horvathi is critically endangered.[1]

Morphology

The snout-vent length of the body and weight ranges between 2.3 cm and 0.4 g in newborns and 7 cm and 7.8 g in adults (Manvelyan, Tadevosyan, 2000). There is a sexual dimorphism in morphology (size, color) and behavior. Females are slightly larger than males. Notably, subspecies P. persicus persicus appears to have a shorter tail compared to that of P. persicus horvathi, ("Phrynocephalus helioscopus horvathi" in author's understanding) (Melnikov et al. 2008). Phrynocephalus persicus as its other relatives does not have visible ear-drums. Head and body are quite wide and covered with small scales. There are no large shield on the head as for example in lacertidae lizards. Coloration in P. persicus is criptic and usually corresponds to the color of the surrounding substrate, which makes the lizard almost invisible. Scales of different size, shape and color associated to create a mosaic pattern, which serves as camouflage allowing the lizard to blend in with the sandy substrate it inhabits. There are two major types of scales on the dorsal surface(Tadevosyan, 2001[5]). Flat scales usually carry a mix of black (malanin), white and orange (xanthines) pigments which create a brown-grey background color, while larger conical scales carry predominantly one type of a pigment (often melanin and xanthines). Accumulartions of conical scales create more or less symmetrically distributed dark spots of the color pattern. The dorsal pattern consists of transverse series of dark dots which form pronounced dark areas on the shoulders and the lumbar region of the body. The center of the back may carry 1–3 lattitudinally spread groups of dark spots, or may be free of any pattern at all (Tadevosyan, 2001[5]). There are usually 2–3 prolonged red surrounded by blue areas on the neck. Color of these areas serves as a "pregnancy indicator". In gravid females red coloration turns bluish-grey and areas become blue. Belly is white with bright orange wash in the rare (abdominal) part. Tail usually carries lattitudinally striped pattern form dark and white segments. Ventral surface of the tail in lizards from Armenia is dark grey in males and yellowish in females.

Biology

Phylogeny within the genus Phrynocephalus is not well understood yet. There is a lack of data and controversy between opinions regarding both phylogenetic relationships and species vs. subspecies status of the different forms Phrynocephalus helioscopus and Phrynocephalus persicus, also called the "helioscopus-persicus complex". The most recent works suggest evidence supporting both. In 2008, Melnikov et al. also proposed a distinction of P. horvathi at the species level.[1][6]

This lizard's life span is only about 2.5–3 years, and juveniles become adults at an age less that one year old. Persian Toad Headed Agamae feed on a variety of available arthropods ranging from ants, small spiders to beetles and orthopterans. Even venomous arthropods as spiders, bees and wasps can be ingested by this lizard.

The Persian Toad-Headed Agama is oviparous, which means that a female lays eggs to reproduce. Females may make 1–3 clutches of 2–4 small eggs, depending on the duration of the worm season, which, in its turn, heavily depends on elevation of the local terrain. The female lays the eggs into a narrow around 30 cm deep burrow she has dug into the sand (Manvelyan, Tadevosyan, 2000). During the period of gravidity, females demonstrate a specifically aggressive behavior towards conspecifics and other invaders as well . This behavior includes walking on extended rear limbs with an inflated abdomen, collateral rotations of the curved end of the tail, tail-markings on the sand, and open mouth attacks (Tadevosyan, 2001).

Conservation

The geographic range of the P. persicus does overlap with the range of intense land use. Therefore, a large scale habitat loss is the major threat for P. persicus. On the other hand overgrazing, uncontrolled collection, road mortality as well as predation by larger animals have been documented as existing threats. Habitats of the lizard are preserved as small islets of semi-desert surrounded by agrarian lands. The species is preserved in the Goravan State Reservation in Armenia. Despite, positive experience in captive breeding of P. h. horvathi (Manvelyan, Tadevosyan, 2000; Tadevosyan, 2001), no stable captive colonies available today.

Proposed subspecies

References

  1. ↑ 1.0 1.1 1.2 Ananjeva, Natalia; Agasyan, Aram (2009). "Phrynocephalus horvathi". The IUCN Red List of Threatened Species. International Union for Conservation of Nature. Retrieved 27 November 2011.
  2. ↑ Melnikov, Daniil; Ananjeva, N.B.; Agasyan, A.L.; Rajabizadeh, M. (2008). "Historical background and taxonomic status of the Persian Toad-Headed Agama Phrynocephalus persicus De Filippi, 1863 and Horwath's Sun-watcher toad-head agama Phrynocephalus helioscopus horvathi Mehely, 1894". Questions of Herpetology: 286–297.
  3. ↑ Solovyeva, Evgenia; Poyarkov, N.A.; Dunaev, E.A.; Duysebayeva, T.N; Bannikova, A.A. (2011). "Molecular Differentiation and Taxonomy of the Sunwatcher Toad-Headed Agama Species Complex Phrynocephalus Superspecies helioscopus (Pallas, 1771) Reptilia, Agamidae)". Russian Journal of Genetics 47 (7): 842–856. doi:10.1134/s1022795411070155.
  4. ↑ Anderson, Steven; Turiyev, Boris; Shafiei Bafti, Soheila (2009). "Phrynocephalus persicus". The IUCN Red List of Threatened Species. International Union for Conservation of Nature. Retrieved 27 November 2011.
  5. ↑ 5.0 5.1 Tadevosyan T.L. 2001. The Fenological Identification of Persian Sun-Watcher Lizards (Phrynocephalus persicus de Filippi 1863. Reptilia, Sauria, Agamidae). // Collect. of articles of the young researchers. Yerevan, «Gitutiun», 1(2): pp. 62–67. (In Russian)
  6. ↑ Melnikov, P.; Ananjeva, N.; Agasyau, A.; Rajabizadeh, M (2008). "On specific and conservation status of P. h. persicus.". Problems of Herpetology (St. Petersburg): 56–63.