AUSTRALIAN BIODIVERSITY RECORD - Calodema

Australian Biodiversity Record, 2009 (3): 1-96
dorsal scales. Additionally, E. marnieae has slightly fewer paravertebrals than E. tympanum.
Some important morphological characteristics are: body scales smooth in adults and sub
adults, but keeled in neonates; dorsal scales 40-48 - counted longitudinally, at midbody (vs
34-44 in E. tympanum); paravertebrals 76-95, about the same size as, or only slightly larger
than adjacent dorsals; parietals in contact behind the interparietal; prefrontals usually
separated, but sometimes in point contact; interparietal elongate, about twice as long as wide,
and almost or usually separating parietals (in E. tympanum the interparietal usually does not
separate the parietals); mature specimens have the upper secondary temporals separated
across the nape by four or five variable, obliquely aligned scales which contact the posterior
margins of the parietals (usually comprised of 1-3 nuchals, plus the upper secondary
temporals); supraoculars 4; supranasals absent; nasals separated; supralabials 6-8 with the
5 th or 6 th subocular (vs 6-9 in E. tympanum, with the 4 th , 5 th , or 6 th subocular); infralabials 7-9
with postmental in contact with first two infralabials on each side (vs 6-9 in E. tympanum);
lower eyelid movable and scaly; supraciliaries 7-9 (vs 8-10 in E. tympanum); ear-opening
present and conspicuous (larger than nasal scale); no anterior ear lobules; well-developed
pentadactyl limbs that overlap when adpressed; hind limbs much longer than forelimbs; 4th
toe much longer than the 3rd; base of 4th toe broad, and most lamellae with a median groove,
and divided basally; 20-26 subdigital lamellae beneath 4th toe. Premaxillary teeth usually 8.
Attains a maximum total length of around 270 mm., and a snout-vent length of about 100 mm.
Variation in morphology suggests that this species may be polytypic.
In my opinion the two distinct populations of this species could be separately classified as
subspecifically distinct from each other. The nominate form - Eulamprus marnieae marnieae
occurs around Dreeite, while the other Eulamprus marnieae subsp. nov. (as yet unnamed),
occurs around Lake Bolac and elsewhere.
Distribution: Known only from a small area of ancient crater lakes and their environs in southwestern
Victoria around Lake Corangamite, the Streatham area, Nerrin and Lake Bolac, with
most locations being in the vicinity of the Dreeite area.
Habitat: Lives among basalt rocks and tussock grasses in fairly damp, cool situations, usually
near permanent or ephemeral water courses, swamps, lakes and soaks. The habitat is rainfall
deficient in the hotter Summer period, but Autumn and Winter rains flood low-lying parts,
providing moist conditions beneath rock outcroppings that sustain the species during the drier
months. It occupies low stony rises where it shelters in both rock crevices and in short earth
burrows beneath basalt rocks, and also occurs in habitats that have been long subjected to
stock grazing, where they have colonized basalt dry-stone walls of farms. The available
natural habitat is very restricted in area, and is completely surrounded by unsuitable habitat
only occupied by Eulamprus tympanum. Rock removal (to increase grazing land, as well as
the past selling-off of the old dry-stone walls for garden rocks), vegetation clearance,
excessive grazing and damage to water quality by pollutants can all negatively impact on this
species.
Biology/Ecology: A shy, retiring species when disturbed, quickly retreating into rock crevices
and other protective cover at the slightest disturbance. Feeds mainly on small invertebrates,
such as spiders, beetles, snails, grasshoppers, and various aquatic species. It will also eat
small lizards, and the fruiting bodies of the Volcanic Plain Tree Violet (Melicytus (cf) dentata)
as well. Viviparous, producing from 2-7 large young in late December-early January
(Summer).
Survival Status: Federally, this taxon is classified as Endangered under the Commonwealth
Environmental Protection and Biodiversity Conservation Act (1999) (listed as Eulamprus
tympanum marnieae). Protected under the Victorian Wildlife Act (1975) and listed as
Threatened in Schedule 2 of the Victorian Flora and Fauna Guarantee Act (1988) [see also
Threatened Fauna Act (1995)]. Regarded by some as critically endangered in Victoria.
Etymology: The marnieae honours Marnie Lincoln Rawlinson.
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