Blattidae - Periplaneta australasiae
Size: 23-29 mm (Helfer1953)
Group Guild Status
Eutroglophile Scavenger Common
P. australasiae is an omnivorous scavenger that is not native to North America, but which has become widespread in the southern U.S. The species has a global distribution, is thought to have a tropical African lineage, and was likely not “Australasian” in its origin (Helfer 1953). This species was not recorded during the initial study, but was likely established during the commercial development of the cave, where the animals and/or their egg cases may have been among construction supplies or equipment brought to the site. Interestingly the animals seem to be primarily limited to peripheral areas of the cave such as the entrance tunnels. Few have been found very far into the cave, and the occasional records in the cave interior are likely to be individuals that have ridden in on visitors, followed the tour tails, or flown into the deeper portions of the cave because they were attracted to the tour lights. They seem to have a permanent presence in the Jackrabbit Shaft area, but we have not observed very many at one time. There are several predators in the Jackrabbit Shaft that may be preying on various age classes of the cockroaches. These include the vaejovid scorpion, the Banded Gecko (Coleonyx variegatus), the house centipede (Dendrothereua sp.) and the brown spider (Loxosceles sp.). Since this species has likely been established in the cave since the construction period, and there appear to be no identifiable adverse effects to the ecology of the cave resulting from its presence, it probably does not represent a significant potential impact on native invertebrates that are resident in the cave. Whether the animals could expand their distribution further within the cave is not known, but seems unlikely.
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