What Bug Is That? The guide to Australian insect families.

Logo: What Bug Is That? Logo: Taxonomy Research & Information Network



Larvae usually live in sand, mud, and leaf litter, and apparently feed on decaying organic matter. Hyphalus larvae have anal gills for living submerged during high tides. [Britton 1971, 1977; Lawrence 1987a; Paulus 1970; Spilman 1959.]


Very small, oval and moderately convex beetles, clothed with decumbent, erect or occasionally minute and pruinose vestiture. They resemble some Byrrhidae in having ventral cavities into which legs can be folded, but they differ from byrrhids in being much less convex and usually by having slender antennae, a longer prosternum which extends well in front of the coxae, a distinct transverse metasternal suture, and a frontoclypeal suture. Paralimnichus lacks the transverse metasternal suture and has lobed tarsi similar to those in byrrhids, but differs from them in having all 5 ventrites connate and the eyes deeply emarginate. Pseudeucinetus has a short prosternum, but it is distinguished by the large, oblique hind coxae and dorsally placed eyes. This genus and Hyphalus also differ from other limnichids in having 4-segmented tarsi.

Limnichid larvae are cylindrical and resemble some kinds of byrrhid larvae, but they are easily distinguished from them by having the maxillolabial complex consolidated, so that the cardines are contiguous, the maxillary articulating areas are absent and the postmentum is joined to the stipites for most of its length.


The Australian fauna is relatively rich, but few species have been described. Many northern species belong to the tropical genus Byrrhinus , but several other genera are represented. Hyphalus occur in interstices of intertidal coral slabs on the Great Barrier Reef, and are also known from Lord Howe I., Norfolk I., New Zealand, and the Cocos-Keeling Islands. Limnichids often occur in riparian situations and large numbers may be attracted to lights at night.