Aprasia striolata

The Striated Worm-Lizard: A Legless Reptile of Southern Australia

The striated worm-lizard, scientifically known as Aprasia striolata, is a distinctive species of legless lizard belonging to the family Pygopodidae. This reptile is endemic to the southern regions of Australia, with populations found in southern Western Australia, South Australia, and western Victoria. Its common names, including striated, striped, or lined worm-lizard, are derived from the characteristic pattern of long, thin, parallel streaks that often adorn its pale brown, olive-brown, or grey body. Some populations, particularly those in Western Australia and on Kangaroo Island, may exhibit absent stripes or have these markings present as rows of dots.

Physical Characteristics and Habitat

As a member of the Pygopodidae family, the striated worm-lizard displays extreme body elongation and lacks limbs, giving it a snake-like appearance. Its body is slender and cylindrical, featuring a rounded and blunt snout and relatively large eyes. The underside is typically whitish. While females generally grow larger than males, their precise snout-to-vent length is not detailed. These lizards are adapted to burrowing and inhabit a diverse range of environments, primarily those with dry sandy or loamy soils.

Diet and Behavior

The diet of Aprasia striolata is highly specialized, with over 95% of their food intake consisting of ant brood, meaning the larvae and pupae of ants. While males may occasionally consume adult ants, this constitutes a small portion of their diet. Prey is swallowed whole, which is consistent with their greatly reduced dentition. Behaviorally, these lizards feed infrequently, typically only during the warmer months, and are noted for 'binge feeding,' consuming a substantial amount of prey in a single instance. How they locate ant colonies or defend themselves against adult ants remains an area of scientific inquiry.

Reproduction and Conservation

Reproduction in Aprasia striolata is oviparous, with females laying thick-shelled, elongate eggs. Evidence suggests that both males and females can reproduce year-round, potentially allowing females to produce multiple clutches per year, a trait that deviates from the seasonally based reproductive cycles common in other southern Australian reptile species. The differences in dentition between adult males and females, with males possessing premaxillary teeth while juveniles and females lack them, are thought to be linked to sexual selection rather than dietary differences. Historically, much of their habitat has been cleared for agriculture and tree plantations. Despite these pressures, the striated worm-lizard is currently listed as 'Least Concern' on the IUCN Red List due to its wide distribution and the absence of major overarching threats.