MONITOR - JOURNAL OF THE VICTORIAN HERPETOLOGICAL SOCIETY 10 (2/3) 1999:24-32MONITOR Copyright - JOURNALVictorian OFHerpetological THE VICTORIAN Society HERPETOLOGICAL SOCIETY 10 (2/3) 1999 AUSTRALIA’S DWARF PYTHONS – GENUS ANTARESIA RAYMOND T. HOSER 41 Village Avenue, Doncaster, Victoria, 3108, Australia. Phone:+61 3 9857-4491 Fax: +61 3 9857-4664 E-mail: [email protected] INTRODUCTION comment as dogma, readers should be aware that it Australia’s dwarf pythons were, until the early 1980’s, has been argued by some that the Wells and Wellington classified by most herpetologists as a single species, description was inadequate in terms of diagnostic namely the Children’s Python (Liasis childreni). An information and is therefore invalid. Wells and 1873 classification of the eastern form ‘maculosus’ had Wellington counter that their information as printed is long been regarded as being a junior synonym and sufficient as per ICZN rules, particularly when thus a part of the same species. Few herpetologists in referenced with the specimen lodged at a public the early 1980’s were even aware that such a synonymy museum, to wit the Australian Museum in Sydney. even existed. However the preceding dispute is probably not the main Things began to change when in 1981 I wrote a paper reason why the Wells and Wellington name wasn’t formally describing the Western Australian form as a adopted by most authors following its publication. You new species. At the same time I also sought to see shortly thereafter there was a petition to the ICZN redescribe the Ant-hill Python as Liasis perthensis (as by a substantial number of Australian herpetologists a full species) in a separate paper, which was by that that called for the complete suppression of three works stage erroneously regarded by most as being an invalid by Wells and Wellington (1984, 1985a, 1985b), which name applied to western populations of the so-called included the one relevant here. Although the case Children’s Python. I was told to ‘hold-off’ due to ongoing ultimately failed, the ICZN ruling wasn’t until 1991 (see research by Laurie Smith and others at the Western ICZN 1991 and references therein). By that stage the Australian Museum and as a result, neither paper was name stimsoni was already in common usage and had published (although I had cited both as being in press appeared in a number of books. at various stages in 1981-2; e.g. Hoser (1981)). (I Which of the two names is ultimately deemed correct suppose this is one good reason why authors should may in part hinge on a separate case currently before never cite material as being ‘in press’). the ICZN, where it has been proposed to suppress In 1985 Smith published a long awaited paper (Smith, another Wells and Wellington name (Varanus 1985), dividing what was formerly regarded as a single keithhornei) in favor of a junior synonym (Varanus species, the Children’s Python Liasis childreni into three teriae) on the basis of common usage of the latter. If geographically exclusive species. He also accepted that case succeeds then a similar fate probably awaits that perthensis was a separate (fourth) species in its the name saxacola. If the case fails, then it is likely own right. Although there is debate as to the validity of that the name saxacola may prove to be correct, and this division (see later) and one of the names used by stimsoni relegated to nomen nudem or at best a Smith, I will for the time being treat these snakes as subspecies. three similar but separate species. These are:- A further spanner in the works was the date of the two 1/ Children’s Python Antaresia childreni of tropical publications. It appears that both the Western Northern Australia west of Cape York, Queensland, Australian Museum and Wells and Wellington including some offshore islands. backdated their publications (date printed on the cover or inside) to be some months prior to actual publication. 2/ Spotted Python Antaresia maculosus of coastal Notwithstanding this, it appears that the Wells and Queensland and nearby areas, including offshore Wellington one was still the first to be published. (My islands, nearby highlands and slopes and north-east own opinion on the matter of stimsoni versus saxacola New South Wales. is that a submission be made to the ICZN for a ruling 3/ Stimson’s Python Antaresia stimsoni (newly one way or the other, particularly in light of the relative described by Smith) of most other parts of Australia, simplicity of making petitions to the ICZN. Otherwise including arid areas. Not found in most parts of the far the issue could fester for decades). I think it is most south of Australia, the far south-east and Tasmania. important for the snake to carry a name and an agreed Found on at least some islands off the W.A. coast proper name at that. Which name this ultimately is, (Maryan, 1984). should be of secondary consideration. Smith’s name ‘stimsoni’ although now widely used, is Without siding one way or the other, I will for the rest of quite probably invalid. You see some months earlier this paper use the name stimsoni to describe the arid Wells and Wellington described the same species as form formerly regarded as a race of childreni on the Antaresia saxacola. Due to the rule of priority, the Wells sole basis that most readers recognise this at the and Wellington name should (in theory) be the correct present time (1999). one to use. However before treating the preceding 24 MONITOR - JOURNAL OF THE VICTORIAN HERPETOLOGICAL SOCIETY 10 (2/3) 1999 ANTARESIA the wild (Hoser, 1993a), the following keys (below) can The genus name Antaresia was also proposed by Wells be used with a high degree of success and certainty to and Wellington. It appears to have been accepted by separate the above snakes from all other pythons. most authors since 1991 without dispute. The genus Although the keys may appear technical, persons encompasses the smaller Australasian pythons, experienced with the relevant snakes will not usually formerly lumped in the genus Liasis, and occasionally have to use them to identify the snake in question. referred to as Bothrochilus. (Bothrochilus is now usually only applied to the species ‘boa’). Etymology for the (Ant-hill Pythons Antaresia perthensis found in the name Antaresia comes from Antares, the yellow giant Pilbara and nearby parts of Western Australia, are star in the ‘tail’ of the constellation of Scorpius. substantially different to the above snakes and are not Incidentally, Wells named his daughter Antares. the main subject of this paper. They are not known to hybridize with any other species. They are covered in HYBRIDISATION detail in a paper later in this journal. (Also see Hoser Although Hybrids of the above three snakes (childreni (1992, 1995) for detailed accounts and then current et. al.) are known to exist in captivity and possibly in bibliographies for the species). KEY TO PYTHONINAE GENERA (EXCLUDING CALABARIA) la Labials wihout pits Aspidites lb Labials with pits 2 2a Premaxilla with teeth Chondropython 2b Premaxilla with teeth 3 3a Postorbital bone extends downward to meet the maxillo-ectopterygoid joint 4 3b Postorbital bone fails conspicuously to reach the maxilla and ectopterygoid Antaresia 4a Minimum of more than 47 scales from one side to other on the neck Python 4b Intercostal arteries arise from the dorsal aorta in groups of three to four in the anterior trunk Morelia KEY TO ANTARESIA, BOTHROCHILUS AND LEIOPYTHON la Single loreal 2 lb Two or more loreals 3 2a Less than 257 Ventrals Bothrochilus boa (Bismark Ringed Python) 2b More than 257 Ventrals Leiopython albertisi (White-lipped Python) 3a Fewer than 37 mid-body scale rows, 250 or less ventrals perthensis (Ant-hill Python) 3b 37 or more mid-body scale rows, 250 or more ventrals 4 4a No pattern, or if pattern is present it isn’t bold and distinct childreni (Children’s Python) 4b Bold pattern 5 5a Pattern of distinct blotches or spots, which may join along the dorsal midline maculosus (Spotted Python) 5b Pattern of bold blotches or bars and a white ventro-lateral stripe along the anterior part of the body stimsoni (=saxacola) (Stimson’s Python) 25 MONITOR - JOURNAL OF THE VICTORIAN HERPETOLOGICAL SOCIETY 10 (2/3) 1999 COLOUR See photos in this article for typical examples with locality information. Also see Hoser (1989) and Kend (1997) for further photos of these snakes and excellent habitat photos. BIOLOGY IN WILD Snakes of the childreni complex (and the Ant-hill Python) all tend to have similar requirements and preferences in the wild. In the wild these snakes are found in almost all types of habitat where they occur, ranging from very arid to very wet and from flat areas to hills. Having said this, there are some types of habitats that are most favoured. Hilly (and especially rocky) areas are preferred over flat and un-rocky areas. Childr en’ s Python ( Antar esia c hildr eni ) Essentially these snakes appear to prefer well-drained fr om Kunnanur ra, W A. areas with lots of ground cover. Preferred vegetation is varied, but in arid areas, spinifex (Triodia sp.) is a most favored ground cover, compared with most other types of plant. It is a highly impenetrable but flammable type of grass that grows outwards in a circle and is common in many arid areas. In it’s own right, spinifex provides excellent cover for reptiles, even in the hottest of places. For example, I retrieved a resting adult male Ant-hill Python from a small exposed spinifex clump at 12:10 PM (ten past noon), by burning the bush.