Allothrips Hood

Allothrips Hood, 1908: 372 . Type-species A. megacephalus Hood, by monotypy.

This genus currently comprises 23 species from various parts of the world. Confusing patterns of variation within and between populations led to the suggestion that these wingless thrips form localised demes, with the result that most of the nominal forms were treated as subspecies associated with one of two clines, one across North America (Stannard, 1955) and one across the Palaearctic (Mound, 1972a). Adding to these problems in species level taxonomy, there is evidence that some of the nominal forms have been dispersed across the world, presumably by human trading involving shipping or aircraft. Thus A. brasilianus Hood is known from Rio de Janeiro and Hawaii (Sakimura & Bianchi, 1977), the three forms described from Australia share many character states with forms known from South-Western USA, and two forms from Northern India are scarcely distinct from forms known from California (Mound, 1972a).

In all but two of the described species (or subspecies) there are four pairs of major setae on the head (interocular, postocular, lateral postocular, and midvertex), but in both A. brasilianus and A. magnus Okajima & Urushihara the midvertex setae are scarcely larger than the minor setae on the vertex. The new species described below similarly has this pair of setae unusually small, but in addition the lateral postocular setae are also small, and the interocular setae are only a little larger (Fig. 8). Furthermore, the third antennal segment of this species has a prominent sub-basal flange unlike any other member of the genus (Fig. 10). Despite this difference, a similar sub-basal flange on the third antennal segment occurs in one or more species of several unrelated genera of Phlaeothripidae, suggesting that its use in defining genera needs to be re-considered (Mound & Minaei, 2007).