Deplorothrips chydaeus, Mound, Laurence A. & Tree, Desley J., 2016

Mound, Laurence A. & Tree, Desley J., 2016, Australian mycophagous species of the genus Deplorothrips (Thysanoptera, Phlaeothripinae), Zootaxa 4208 (3), pp. 201-220 : 210-211

Deplorothrips chydaeus sp.n.

( Figs 8 , 21 , 38 )

Male aptera: Body and all femora brown, tibiae and tarsi light brown; mid and hind tibiae yellow in basal third, sometimes yellow at apex; antennal segments I–II light brown, III variably yellow toward base and variably light brown toward apex, IV–VIII darker brown.

Antennal segment VIII broadly joined to VII, IV–VII narrowed to pedicel ( Fig. 21 ); III with two sense cones, IV either with two large sense cones or with one large and two smaller ones. Head longer than wide ( Fig. 8 ), sometimes with one or two weakly developed ocelli, cheeks with weak setae; vertex with no sculpture; po setae long and capitate; maxillary pillars about 50 microns long but with the levers no more than 30 microns, stylets wide apart and retracted half way to po setae. Pronotum with weak median longitudinal apodeme, without sculpture; am setae minute, remaining setae capitate. Mesonotum without sculpture, lateral setal pair minute, no wing lobe. Metanotum without sculpture, median setal pair slender and acute. Fore femora stout, fore tarsal tooth as long as tarsal width, fore tibia with small subapical tubercle. Prosternal ferna not meeting medially, mesopraesternum eroded to two small sclerites and a slender band medially. Pelta eroded, irregularly D-shaped; tergites with no sculpture, II–VII with 2 pairs of very small, straight wing-retaining setae, lateral major setae weakly capitate; tergite IX setae S1 long and capitate, S2 short and pointed. Sternites III–VI often with transverse rows of reticulation anterolaterally, VIII with oval pore plate ( Fig. 38 ).

Measurements (holotype male in microns). Body length 1400. Head, length 160; width 150; po setae 50. Pronotum, length 135; width 190; major setae—am 5, aa 35, ml 20, epim 43, pa 30. Tergite IX setae S1 50, S2 25. Sternite VIII pore plate dimensions 40 x 18. Tube length 85. Antennal segments III–VIII length 45, 47, 47, 40, 40, 23.

Female aptera: similar to male, sense cones on antennal segment IV equally variable; po setae shorter than dorsal eye length; fore tarsal tooth acute, shorter than tarsal width; tergite IX setae S1 and S2 capitate, scarcely longer than basal width of tube.

Female macroptera: similar to male but larger; antennal segments III–IV with sense cones varying in number and sometimes not bilaterally symmetrical, III with 2 or 3, IV with 2 or 4; ocelli well-developed; fore tarsal tooth length about half of tarsal width; fore wing shaded on distal half, with 4 or 5 duplicated cilia and 1 or 2 small capitate sub-basal setae; pelta triangular; tergites each with 2 pairs of sigmoid setae.

Material studied. Holotype male aptera, New South Wales, Tallaganda , Lowden Forest Park, from dead Eucalyptus branches, 27.ii.2011 ( LAM 5431 ).

Paratypes (apterae except as noted): New South Wales, 6 female macropterae, 3 females, 3 males taken with holotype; same site and from dead Eucalyptus , 7 males, 2 females, 6.viii.2006 ; 3 female macropterae,1 male, 12.xi.2006; 7 female macropterae, 2 females, 9.ii.2013; Tinderry Range , 1 female macroptera, 7 females, 5 males from dead branches, 29-30.ii.2013 . Australian Capital Territory, Mt Ainslie , 2 female macropterae, 5 females, 1 male from dead twigs, 11.vi.1995 . Victoria, Mallacoota , 2 female macropterae, 1 female, 1 male from Eucalyptus dead nuts, 1.iv.2011 ; Nelson, 1 female from dead Eucalyptus nuts, 5.x.2013 . South Australia, 40km southeast of Mt Gambier , 7 female 2 male macropterae, 5 males, 4 females from Eucalyptus obliqua nuts, 12.ii.2011 . Queensland, Brisbane Forest Park, 2 female macropterae, 3 females, 2 males from dead branches, 3.iv.2011 ; same locality, 1 female macroptera . 5 females, 2 males on various dates between xi.2007 and iii.2013; Stanthorpe , 3 females, 2 males from dead wood, 28.xii.2011 ; Girraween , 1 female macroptera, 1 female, 2 males from dead wood, 29.xii.2011 .

Comments. This species exhibits confusing variation in several structures. The largest males have the cheek setae more prominent, the fore femora swollen, each fore tibia with a well-developed subapical tubercle, the fore tarsus very stout, and conspicuous reticulate rows on the sternites, whereas each of these characters is more weakly developed or even absent in small males. The number of antennal sense cones varies even within the series taken with the holotype. Macropterae usually have 3 on III and 4 on IV, but some macropterae have only two on both segments, and some apterae have 2 on III but 3 on IV. Moreover, some of the apterae have one or both posterior ocelli weakly developed. Despite the maxillary stylets being retracted into the head half way toward the level of the postocular setae, this species exhibits all of the other character states that are typical of Deplorothrips . The tube is relatively short and slightly paler toward the base, and tergite IX setae S1 are scarcely longer than the width of the tube. A series of six females and two males have been studied from Carnarvon Station, Queensland that are essentially similar to this species but have longer setae; po setae 63 microns; S1 on tergite IX 75 microns. A number of specimens of both sexes have been seen from various sites in Tasmania, including Flinders Island, that cannot be placed to species securely. Most, but not all, of the females have the pronotal am setae small and capitate as in norfuki from Norfolk Island, but the males have an irregularly transverse oval sternal pore plate as in chydaeus , and the macropterae have three sense cones on antennal segment III and four on IV, whereas the apterae have two sense cones on both segments.

Figures

FIGURES 8 – 13. Deplorothrips species, head and thorax. (8) chydaeus female; (9) capitalis holotype; (10) howei holotype; (11) minaei female; (12) retis holotype; (13) deuae female.

FIGURES 20 – 32. Deplorothrips species, antennae. (20) diaphorus, macroptera, segments IV – VIII ventral; (21) chydaeus; (22) deuae (holotype); (23) howei; (24) makrus; (25) minaei; (26) mongai; (27) norfuki; (28) paspalus; (29) regina; (30) retis; (31) virgulatus; (32) villosus.

FIGURES 33 – 47. Deplorothrips species, metanotum and male sternites. (33) howei, large male, meso and metanotum. (34) regina, metanotum and tergites I – II. (35) retis, metanotum and pelta. (36) villosus, large male, metanotum and tergites I – II. (37) norfuki, holotype metanotum and tergites I – II. Male sternite VIII pore plate 38 – 44: (38) chydaeus; (39) deuae; (40) diaphorus; (41) howei; (42) makrus; (43) mongai; (44) villosus. (45) howei, male fore tarsus & tibia. Male sternites V – VI 46 – 47: (46) capitalis; (47) diaphorus.