The yellow-faced whip snake (''Demansia psammophis'') is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

venomous snake Venomous snakes are Species (biology), species of the Suborder (biology), suborder Snake, Serpentes that are capable of producing Snake venom, venom, which they use for killing prey, for defense, and to assist with digestion of their prey. The v ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Elapidae Elapidae (, commonly known as elapids ; grc, ἔλλοψ ''éllops'' "sea-fish") is a family of snakes characterized by their permanently erect fangs at the front of the mouth. Most elapids are venomous, with the exception of the genus Emydoceph ...

, a family containing many dangerous snakes. ''D. psammophis'' is endemic to Australia, found throughout the continent in a variety of habitats from coastal fringes to interior arid scrubland.

Taxonomy

The yellow-faced whip snake is part of the ''

Demansia ''Demansia'' is a genus of venomous snakes of the family Elapidae. Members of the genus are commonly known as whip snakes or whipsnakes, as are members of several other genera. Description All species of the genus ''Demansia'' are gray, brown, ...

'' genus, a group of venomous snakes from the Elapidae family. This genus is composed of whip snakes, characterized by their large eyes and whip-like tail. The ''

'' genus is commonly found in the Southern hemisphere around Australia and equatorial countries such as Papua New Guinea. There are currently 14 species that have been identified under the genus ''Demansia'', these include:

Description

''Demansia psammophis'' is a long thin snake with a narrow head. ''D. psammophis'' grows up to a total of 1m in length, averaging around 80cm in length, females being slightly smaller than males. Characterized by their narrow yellowish head, pale ring around the eyes, and a dark marking curving along the upper lip, ''D. psammophis'' becomes distinguishable from other ''Demansia'' snakes. Juveniles can be distinguished as a white-edged dark line is seen across the snout. The large prominent eyes surrounded by a pale ring, account for its ability to be a successful diurnal species, having the largest eyes of any Australian snake assisting in prey capture. The colour of yellow-faced whip snakes varies, ranging from olive green, grey and brown; however, a common characteristic in colour is a ‘red flush along the anterior third of its back'. To accurately identify this species, there must be a clear view of the head, and the scales around the snake's mid-body must be counted. ''D. psammophis'' has 15 midbody scale rows and between 165-230 ventrals, with the anal and subcaudals divided. ''Demansia psammophis'' is commonly confused with the eastern brown snake (''

Pseudonaja textilis The eastern brown snake (''Pseudonaja textilis''), often referred to as the common brown snake, is a species of highly venomous snake in the family Elapidae. The species is native to eastern and central Australia and southern New Guinea. It was ...

''), due to their similar appearance.

Distribution and habitat

''Demansia psammophis'' are distributed throughout the Australian continent, with presence in every state except Tasmania. Although the distribution of ''D. psammophis'' is wide, it is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to Australia. Found in a variety of habitats across Australia, ''Demansia psammophis'' ranges from coastal forests to arid scrublands and grasslands in Australia’s interior. It is not uncommon to find more than one ''D. psammophis'' as they are community dwellers. Habitats in rock crevices and under logs are common community habitats with communities often aggregating in winter months.

Behaviour

''Demansia psammophis'' are diurnal reptiles, fast-moving with a nervous disposition, always alert and fleeing quickly when disturbed. The yellow-faced whip snake is subject to

brumation Dormancy is a period in an organism's life cycle when growth, development, and (in animals) physical activity are temporarily stopped. This minimizes metabolic activity and therefore helps an organism to conserve energy. Dormancy tends to be clos ...

, or slowing down their movements, in the winter months, usually only moving to seek sun and water.

Reproduction

''Demansia psammophis'' are

oviparous Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and ...

, laying clutches of 5-6 and 15-20 amniotic eggs. Communal egg laying is also common among the species, with some nests having between 500-600 eggs present. ''D. psammophis'' females experience

vitellogenesis Vitellogenesis is the process of yolk protein formation in the oocytes of non mammalian vertebrates during sexual maturation. The term ''vitellogenesis'' comes from the Latin ''vitellus'' ("egg yolk"). Yolk proteins, such as Lipovitellin and P ...

between September and November, ovulating in late spring or summer. Hatchlings are approximately 17cm in length from snout to base of tail and are laid between February and March.

Diet

Small diurnal lizards are the main source of food, as well as lizard eggs. ''D. psammophis'', although diurnal, forage during the night, catching nocturnal forms such as geckoes, lerista and frogs. Demansia psammophis Berowra Creek

Predation and Venom

Small reptiles such as lizards and skinks are predated on by ''D. psammophis'', during the day. Juvenile ''D. psammophis'' have been observed to constrict their prey, however, as they become adults, constriction becomes uncommon, with the species occasionally creating a single body loop to restrain their prey. To immobilize and kill prey, ''D. psammophis'' lash out and inject toxic venom, slowing and eventually killing their prey. Although this venom is deadly to other reptiles and amphibians, it is not considered dangerous to adults. If bitten, the bite will be painful and the injection of venom will cause localized pain and swelling, ranging from moderate to severe, with some bites causing systemic symptoms such as paralysis and bleeding. Medical treatment should be sought following any snake bite.

Conservation

Yellow-faced whip snakes are currently classified as

least concern A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...

under the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

and are considered stable. The species is secure under the status of least concern in the majority of States and Territories in Australia, including QLD and the NT; however, they are considered near-threatened in Victoria. ''D. psammophis'' is not found in Tasmania due to the Tasman Strait that separates it from mainland Australia and the climatic conditions of Tasmania.

References

Sources

* Weigel, John (2002). ''Australian Reptile Park's Guide to Snakes of South-east Australia''... * Cotter, Harold G.(Oct 2018. Updated Seventh Edition.) “REPTILES AND AMPHIBIANS OF AUSTRALIA.” . (''Demansia psammophis'', p. 50). * "''Demansia psammophis'' ". Integrated Taxonomic Information System. www.itis.gov. ITIS
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