Ceratomerus ordinatus, Hardy, 1930

Bradley J Sinclair, 2003, Taxonomy, Phylogeny and Zoogeography of the Subfamily Ceratomerinae of Australia (Diptera: Empidoidea), Records of the Australian Museum 55, pp. 1-44 : 27

Ceratomerus ordinatus species-group

This Australian species group of Ceratomerus is characterized by a lengthened pedicel (second antennal segment), stigma absent, long postocular bristles overlapping eye, widely spaced ocellar bristles, third dorsocentral bristle shorter than others, and posterior fringe of female tergite 7 lacking. In addition, a number of species have a short, dorsomedian projection from the apex of the fifth tarsomere. Several of the above characters are also present in undescribed species from New Zealand and Ecuador and possibly indicates close phylogenetic relationships among all these taxa.

Species of this group were observed to be quite active runners over rocks in and along the banks of creeks. Upon alighting on a rock, they often immediately run about, in contrast to taxa of other species groups which appear to be much less active and reclusive.