Mole Creek Harvestman

The body of H. gibbergunyar ranges from 5–7 mm (0.20–0.28 in) in length, and is light brown with darker brown patterning. IT has elongated legs that are more than three times the length of the body. It has a low, oval body with a prominent eye mound bearing a small upward-projecting spine, a feature that distinguishes Hickmanoxyomma from a similar genus, Odontonuncia. The jaws (chelicerae) are small but armed with a large spine and several smaller dorsal spines, and the short "pincer‑like" appendages (pedipalps) beside the mouth are fairly strong and spiny, helping it to grip prey or detritus. Females are similar to the males, but have a smaller body, with shorter, narrower pedipalps that have thinner, less developed spines.

Hickmanoxyomma gibbergunyar is only found in the Mole Creek karst system of central northern Tasmania, where it is widespread and seldom common in any given cave, though occasionally locally abundant. This species has been recorded in at least 10 caves within this karst system, including:

Anastomosis Baldocks Cave Cow Cave-Pyramid Link Cyclops Cave Georgies Hall Herberts Pot Honeycomb Cave Kubla Khan Cave Westmorland Cave Wet Cave Wombat Cave However, it is likely to be more widespread than currently known. As of 2005, there is no evidence that the distribution of this species has recently declined.

H. gibbergunyar is one of 195 species found in the 509 known caves of the Mole Creek karst area; this high species diversity partially reflects the intensity of study in Mole Creek relative to other karst systems. As an invertebrate within a Tasmanian cave community, H. gibbergunyar lives in a low-nutrient environment that relies on both natural organic input from the surface and the recycling of nutrients within the karst ecosystem. This relative lack of nutrients means that abundance and biomass of Tasmanian cave fauna tends to be low, even if diversity is high.

Diet. Aside from the Tasmanian cave spider (Hickmania troglodytes), harvestmen such as H. gibbergunyar act as the top predator within the Mole Creek Karst system, feeding on invertebrates like crickets (eg. Micropathus cavernicola, Parvotettix goede), beetles (eg. Tasmanotrechus cockerilli) , and potentially glow worms. They search for prey using their long legs and sensory organs, before ambushing them using their thorny, highly armoured chelicerae and pedipalps (pictured right). They may also scavenge on detritus, such as epigean animals, rotting vegetation, and other organic matter washed in through creeks and streams, as well as faeces and carcasses.

Predation. Direct predators of H. …