Pygothrips Hood, 1915

Mound, Laurence A. & Tree, Desley J., 2021, Tubuliferous Thysanoptera inAustralia with an enlarged tenth abdominal segment (Phlaeothripidae, Idolothripinae), including six new species, Zootaxa 4951 (1), pp. 167-181 : 175

Pygothrips Hood

Pygothrips Hood, 1915: 49 .

Type species P. rugicauda Hood.

There are currently 17 species listed in this genus (ThripsWiki 2021), of which eight are from the warmer parts of the Americas, three from southern Japan, one from Indonesia, two from Fiji and four from Australia (including one that is widespread in southeast Asia). The type species has previously been known only from a single wingless female that was taken in northern Queensland, but specimens taken widely across Australia are reported here as closely similar to this holotype and are identified provisionally as this species. In a revision of the nine Pygothrips species known from the Old World, Okajima (1990) provided a detailed diagnosis of the genus in which he stated that antennal segment IV has four (rarely two) sense cones. At that time, it had not been confirmed that the type species, rugicauda , is the only species in the genus with just two sense cones on this segment. Moreover, rugicauda is the only species among the nine discussed by Okajima that has the tube grossly swollen and bearing large numbers of prominent short setae on the surface. Currently, Pygothrips is distinguished from Acallurothrips at sub-tribal level because of the position of the maxillary stylets close together medially in the head ( Figs 20–22 ). As indicated above in the Introduction, convergence in the form of the tenth abdominal segment among these thrips is presumably associated with their behaviour. Two of the species considered here, pygus and shavianus , are probably only distantly related to the other members of Pygothrips , judging from the presence of a complete mesopresternum, the slightly wider separation between the maxillary stylets in the head, a pronotum that is remarkably short medially ( Fig. 20 ), and less rounded median antennal segments. These two species differ remarkably from each other in the form of the tube. They were both described originally in the genus Cryptothrips despite having four sense cones on antennal segment IV, whereas the type-species of Cryptothrips has only three sense cones on that segment. In Pygothrips species the sense cones on antennal segments III and IV are often small; the inner sense cone on III is sometimes scarcely visible, and the ventral pair of sense cones on segment IV may be less than half the length of the dorsal pair.

Figures

FIGURES 14‒22. Heads of Acallurothrips. Neosmerinthothrips, Ozothrips and Pygothrips species. (14) A. nogutti. (15) A. erubi sp.n. (16) A.darumbali sp.n. (17) N.barrowi sp.n. (18) N.turrbali sp.n. (19) O. meanjini sp.n. (20) P. pygus. (21) P. shavianus. (22) P. rugicauda.