Horistothrips australiae Morgan

Horistothrips australiae Morgan

Horistothrips australiae Morgan, 1913: 36

Horistothrips corticis Girault, 1929b: 2. syn.n. Elaphrothrips thoreauini Girault, 1929b: 3. syn.n.

Morgan’s description of this species included the statement “ Type slide contains two females, one wingless and one winged, and three pupae and one larva.” The mention of a “ type slide” is confusing, because the generic description refers to “three females, one winged and two wingless”. A slide that corresponds with Morgan’s statement is available in the US National Museum. However, there is a second slide, re-labelled by J.D. Hood but with Morgan’s original labels on the reverse. One original label indicates “2Ψ s Type slide”, but the word Type has been changed subsequently to “ Paratype ”. This slide bears three pupae (one concealed under the margin) and one larva, together with one male and one female, both micropterae. These are clearly part of the original series, although they are not mentioned with the description, particularly the presence of the male.

The original data was: Australia, Swan River, under dead scales of Eriococcus on Eucalyptus, collected by George Compere, and received at USDA, Washington on 1 March 1902. The Swan River runs through Perth, Western Australia, and a further micropterous female of H. australiae has now been studied from Eucalyptus about 120km South East of Perth.

The two species described by Girault that are here placed into synonymy with australiae were collected together “under bark of living gum, Mt Cootha, 26th January, 1929”. The original specimens, all micropterae, are mounted onto one microscope slide (Fig. 9). The specimen indicated by the label as thoreauini is a large female under one cover glass; the corticis specimens include two large and one small female, with one small male.

In addition to these specimens, from opposite sides of the Australian continent, a few specimens have also been studied from South Australia; one micropterous female from Eucalyptus bark at Willunga, South East of Adelaide, and several specimens of both sexes from under the bark of Eucalyptus camaldulensis at Orroroo (all in ANIC, Canberra). The species is variable in body size and the lengths of some major setae, including the postoculars, both within and between sexes. The specimens from Orroroo are pale, possibly through long storage in alcohol, and the sub-basal area of the third antennal segment is more swollen than in the other available specimens.