Pygothrips rugicauda Hood

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 : 176-178

Pygothrips rugicauda Hood

( Figs 9, 10, 12 , 22 )

Pygothrips rugicauda Hood, 1915: 50

For many years this remarkable species remained known only from the wingless female holotype that was collected in northern Queensland by A.A. Girault, 17.viii.1912. However, in recent years specimens have been taken at various sites between southern Queensland and southern New South Wales as well as in South Australia, and these are here all provisionally identified as the same species. The shape of the tube was illustrated by Hood, such that the ventral surface is almost flat but the upper surface swollen in the basal third and from there slopes down to the anus ( Fig. 12 ). In dorsal view the lateral margins are strongly curved from the broad base to the narrowly constricted anal ring. However, there is considerable variation between the available individuals in the form of the tube, even within the same sample. Most individuals of both sexes have the tube margins strongly convex ( Fig. 10 ), but a few have the tube slightly more slender ( Fig. 9 ). Unfortunately, there are problems in slide-mounting these thrips, such that the swollen tube is commonly crushed or collapsed, with no possibility of seriously assessing the variation within and between samples. The series taken near Canberra was beaten from dead Eucalyptus branches that had extensive Scolytid beetle galleries, and among these specimens the pelta is sometimes so weakly sclerotised that it is almost absent. Apterous individuals have the mesopresternum reduced to a small median sclerite, but macropterae have the mesopresternum transverse and partly fused to the anterior margin of the mesoeusternum. One unidentified large Pygothrips female from Canberra, taken from a branch together with the more typical rugicauda females, has the tube with a series of very stout setae, and the tergite IX major setae long, fine and considerably longer than the tube. In addition to the specimens listed below, the following three specimens (in QDPC) have been studied in which the tube is robust but not swollen, and these seem likely to represent undescribed species: Canberra, one apterous fe- male, 26.ii.2011; Tasmania, Binnalong Bay, two males, 10.xii.2012. Two females listed below from Western Australia near Perth are similar to rugicauda , but the macroptera has the tube more elongate and the pelta well-developed, broadly triangular and similar to that of P. shavianus ; again, these possibly represent an undescribed species.Among the specimens listed below, the head, antennae, and pronotum are essentially identical, but the tube varies slightly in shape within and between samples. Without more extensive field data it is not possible to decide how many of the available specimens represent a single variable species and how many further species exist.

Specimens studied. Australian Capital Territory, from Eucalyptus dead branches: Black Mt. , 2 female macropterae, 1 female, 1 male apterae, 6.iii.2011 ; 3 female apterae, ii.2011; 1 male aptera, 12.iv.2014; 6 female apterae, 1 female macroptera, 19.iv.2011. ACT, Oakey Hill , 1 female, 2 male apterae, iii–iv.2011 . New South Wales, Holbrooke , 1 female, 1 male apterae from Eucalyptus mistletoe, ix.2007 . South Australia, Bridgewater , 1 female aptera from gall on Eucalyptus , 18.vii.1999 . Queensland: D’Aguilar National Park, Mt Glorious , 1 male aptera from dead Eucalyptus , 25.ii.2016 ; Kuranda , 1 male aptera from dead twigs, 2.xi.2008 . Western Australia, Albany 40km north, 1 female macroptera, 1 female aptera, by insecticide fogging of Eucalyptus , v.2001 (in ANIC).

Figures

FIGURES 1‒13. Abdominal segment X variation in shape. Acallurothrips species 1‒4: (1) darumbali sp.n; (2) nogutti; (3) yagara sp.n; (4) erubi sp.n. Neosmerithothrips species 5‒6: (5) barrowi sp.n; (6) turrbali sp.n. (7) Ozothrips meanjini sp.n. Pygothrips species 8‒10: (8) vicinus paratype; (9) rugicauda male; (10) rugicauda female. (11 a, b) Acallurothrips tergites VIII‒X to show setae SB1 and SB2 (from Okajima 1993). (12) Pygothrips rugicauda holotype tergite X dorsal and lateral views (from Hood 1915). (13) Pygothrips pygus tergites IX‒X (from Mound 1974a).

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.