Dwarf monitor

from Wikipedia, the free encyclopedia
Dwarf monitor
Systematics
without rank: Toxicofera
without rank: Sneaky (Anguimorpha)
Family : Varanidae
Genre : Monitor lizards ( varanus )
Subgenus : Odatria
Type : Dwarf monitor
Scientific name
Varanus primordius
Mertens , 1942

The dwarf monitor ( Varanus primordius ) is a species of monitor lizard that is endemic to Australia . V. primordius belongs to the subgenus Odatria . The first description was made of this kind in 1942 by the German biologist Robert Mertens .

Physique and appearance

With a total length of 30 cm and a head-torso length of 13 cm, this species is one of the small-stature among the monitor lizards. The habitus of V. primordius is very reminiscent of the Storrs dwarf monitor ( Varanus storri ). They are also similar in their way of life. Some features in the Pholidose clearly distinguish the two monitor species. On the upper side, the dwarf monitor has a pale, dark reddish brown basic color, with numerous scattered dark brown to black scales, which occasionally form a net pattern. A dark, poorly visible temporal stripe is present in most animals. The neck is white or off-white on both sides and on the bottom. The scales on the head are small, irregularly arranged and smooth. Your nostrils are on the side and a little closer to the tip of the snout than to the eye . There are fewer than 70 rows of scales around the middle of the body. In cross-section, the tail is round with no evidence of a dorsal keel. Its tail is about 1.4 times the length of its head and torso. The caudal scales of the dwarf monitor towards the tail are strongly keeled, with each keel ending in a short but clearly visible sting.

distribution and habitat

The dwarf monitor has patchy ranges within a restricted area in the northwestern Northern Territory , Australia . Its distribution area extends from Darwin to south to Katherine and from Kakadu west to the Daly River region. Within the Daly River region, its range is restricted by unsuitable habitats. The range ends in the east on the South Alligator River . It lives there on stony ground, where it can hide in crevices and under larger stones . The dwarf monitor is often seen on the Adelaide River ( NT ).

Way of life

With its strong prickly tail, it wedges itself into crevices in the rock, so that any predators have little chance of pulling it out. The dwarf monitor probably feeds mainly on insects . Little is known about his way of life.

Systematics

Mertens (1942d, 1963) described the dwarf monitor as a subspecies of the spiny-tail monitor ( Varanus acanthurus ). Storr (1980) raised this subspecies to species status after a taxonomic study carried out by him. In English the species is called Northern Blunt-spined Monitor .

literature

  • Wilson, S. & Swan, G. 2010. A complete guide to reptiles of Australia, 3rd ed. Chatswood: New Holland, 558 pp.
  • Mertens, R. 1966. A new dwarf monitor from Australia. Senckenberg. Biol. 47: 437-441
  • Storr, GM 1966. Rediscovery and taxonomic status of the Australian lizard, Varanus primordius. Copeia 1966 (3): 583-584
  • Mertens, R. 1942. Another new monitor lizard from Australia. Zool. Number 137: 41-44
  • Harold G. Cogger : Reptiles & Amphibians of Australia. 7th edition. CSIRO Publishing, Collingwood 2014, ISBN 978-0-64310035-0 , p. 780.
  • Mertens, R. 1958. Remarks on the monitor lizards of Australia. Senckenberg. Biol. 39: 229-264
  • Eidenmüller, Bernd 2013. From Darwin to Alice Springs - because of the monitor lizards. Draco 13 (53): 55-61

Web links

Individual evidence

  1. ↑ MERTENS 1942d, 1958, KEAST 1959, WORRELL 1966, BUSTARD, 1968, SWANSON 1976, STORR 1980, STORR et al. 1983b, WILSON & KNOWLES 1988, HOSER 1989, COGGER 1992, EHMANN 1992
  2. ↑ Harold G. Cogger: Reptiles & Amphibians of Australia. 7th edition. CSIRO Publishing, Collingwood 2014, ISBN 978-0-64310035-0 , p. 780.