Hemiaspis Damelii
   HOME

TheInfoList



OR:

''Hemiaspis damelii'' 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 ...
of
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 ...
. It is a relatively small species of elapid with a mean snout-vent length (SVL) of . The species 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 eastern Australia and is most commonly found across central inland New South Wales through to the interior of south-eastern Queensland.
Common names In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...
for this species include grey snake and Dämel's Snake. The
specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...
, ''damelii'', is in honor of German
entomologist Entomology () is the scientific study of insects, a branch of zoology. In the past the term "insect" was less specific, and historically the definition of entomology would also include the study of animals in other arthropod groups, such as arach ...
Edward Dämel, who collected Australian specimens for
Museum Godeffroy The Museum Godeffroy was a museum in Hamburg, Germany, which existed from 1861 to 1885. The collection was founded by Johann Cesar VI. Godeffroy, who became a wealthy shipping magnate a few years after the expansion of the trade towards Austral ...
.


Description

''H. damelii'' is a relatively small snake with an average snout-to-vent length (SVL) of 50 centimetres (20 inches). Minor size differences occur between sexes, with the males averaging a slightly larger size than females. It is olive to grey
dorsally Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...
, and white to yellowish white
ventrally Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...
, often flecked with dark grey. In some grey snakes, each scale may be tipped with black
anteriorly Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...
, particularly on the flanks. It has smooth
dorsal scales In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales. Campbell JA, Lamar WW (2004). ''The Venomous Reptiles of the Western Hemisphere''. Ithaca and London: Comstock Publis ...
which are in 17 rows at mid-body, 140-170
ventral scales In snakes, the ventral scales or gastrosteges are the enlarged and transversely elongated scales that extend down the underside of the body from the neck to the anal scale. When counting them, the first is the anteriormost ventral scale that conta ...
, and 35-50
subcaudals In snakes, the subcaudal scales are the enlarged plates on the underside of the tail.Wright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates (7th printing, 1985). 1105 pp. . These scales may be either single or divided (pair ...
which are single (undivided). This species also has a paired (divided)
anal scale Anal may refer to: Related to the anus *Related to the anus of animals: ** Anal fin, in fish anatomy ** Anal vein, in insect anatomy ** Anal scale, in reptile anatomy *Related to the human anus: ** Anal sex, a type of sexual activity involving s ...
.
Juvenile Juvenile may refer to: *Juvenile status, or minor (law), prior to adulthood *Juvenile (organism) *Juvenile (rapper) (born 1975), American rapper * ''Juvenile'' (2000 film), Japanese film * ''Juvenile'' (2017 film) *Juvenile (greyhounds), a greyho ...
grey snakes have a distinctive black head which fades or sometimes completely disappears as the snake matures, occurring from the top of the head to the second scale row behind the parietals.


Distribution and habitat

The distribution and ecology of ''H. damelii'' is poorly known. Existing records of the grey snake are most commonly found in south-eastern
Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...
and north-central
New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...
, however small populations have also been found to occur in north-eastern
South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...
and south-western New South Wales. It tends to favour dry
sclerophyll Sclerophyll is a type of vegetation that is adapted to long periods of dryness and heat. The plants feature hard leaf, leaves, short Internode (botany), internodes (the distance between leaves along the stem) and leaf orientation which is paral ...
forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...
s and
woodland A woodland () is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood (or in the U.S., the ''plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunlight and limited shade (see ...
s on clay soils where water bodies or
gullies A gully is a landform created by running water, mass movement, or commonly a combination of both eroding sharply into soil or other relatively erodible material, typically on a hillside or in river floodplains or terraces. Gullies resemble lar ...
are present. It shelters under rocks, logs and other debris, as well as in cracks in soil.


Reproduction and life cycle

The breeding period for ''H. damelii'' occurs from January to March. During Spring (September-October) adult females'
ovarian follicles An ovarian follicle is a roughly spheroid cellular aggregation set found in the ovaries. It secretes hormones that influence stages of the menstrual cycle. At the time of puberty, women have approximately 200,000 to 300,000 follicles, each with th ...
increase in size following
ovulation Ovulation is the release of eggs from the ovaries. In women, this event occurs when the ovarian follicles rupture and release the secondary oocyte ovarian cells. After ovulation, during the luteal phase, the egg will be available to be fertilized ...
in preparation of the breeding season. ''H. damelii'' has a relatively high
fecundity Fecundity is defined in two ways; in human demography, it is the potential for reproduction of a recorded population as opposed to a sole organism, while in population biology, it is considered similar to fertility, the natural capability to pr ...
, partly due to its large maternal snout-vent length (SVL), which has been found to significantly correlate with litter size. Litter size can range from 4-16 live young which are born fully formed (
viviparous Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the m ...
). The newborns take an average of 12 months to mature after birth.


Diet

The diet of ''H. damelii'' consists predominately of
terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...
anurans A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" ''Triadobatrachus'' is ...
. It has also been found to consume some scincid lizards, however this is quite rare.


Behaviour

''H. damelii'' is active during the night, beginning to move around sunset and remaining active for 1-2 hours after, using this time to hunt and feed.


Venom and symptoms

The venom of ''H. damelii'' is fairly mild and is unlikely to cause fatalities in humans; however, a bite from a larger specimen may be very painful. The venom contains procoagulants and causes local pain and swelling.


Conservation status and threats

In Queensland, ''H. damelii'' is listed as an
endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...
under the '' Nature Conservation Act, 1992.'' It is also listed as endangered on 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 ...
of Threatened Species due to population decline. The key processes threatening ''H. damelii'' include the impacts of
feral animals A feral () animal or plant is one that lives in the wild but is descended from Domestication, domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems an ...
such as cats and foxes via
predation Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...
, cane toads through
ingestion Ingestion is the consumption of a substance by an organism. In animals, it normally is accomplished by taking in a substance through the mouth into the gastrointestinal tract, such as through eating or drinking. In single-celled organisms ingest ...
and feral pigs through
habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...
and competition for food resources. Increasing pasture improvement and cultivation are also destroying habitat through the disruption of soil structure in cracking clay soils. Changes to waterways and the
hydrological cycle The water cycle, also known as the hydrologic cycle or the hydrological cycle, is a biogeochemical cycle that describes the continuous movement of water on, above and below the surface of the Earth. The mass of water on Earth remains fairly cons ...
are also impacting grey snakes which rely on these floodplains and water sources. Recent floods in
NSW ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...
have helped researchers find 30 individual snakes. The venomous snake has only been seen a handful of times in the past 65 years.


References


Further reading

* Günther A (1876). "Descriptions of new species of Reptiles from Australia collected by Hr. Dämel for the Godeffroy Museum". ''Journal des Museum Godeffroy'' 5: 45-47. (''Hoplocephalus damelii'', new species, p. 46). *
Wilson S Wilson may refer to: People * Wilson (name) ** List of people with given name Wilson ** List of people with surname Wilson * Wilson (footballer, 1927–1998), Brazilian manager and defender *Wilson (footballer, born 1984), full name Wilson Rod ...
, Swan G (2013) '' A Complete Guide to Reptiles of Australia, Fourth Edition''. Sydney: New Holland Publishers. 522 pp. . {{Taxonbar, from=Q3130011 Reptiles described in 1876 Taxa named by Albert Günther damelii Snakes of Australia