Pseudanaphothrips Karny, 1921

Mound, Laurence A. & Tree, Desley J., 2025, Species confusion in the Australian inflorescence-living genus Pseudanaphothrips (Thysanoptera, Thripidae), Zootaxa 5696 (3), pp. 425-436 : 426-428

Pseudanaphothrips Karny

Pseudanaphothrips Karny, 1921: 242 . Type species Pseudothrips achaetus Bagnall, 1916 , by subsequent designation of Karny, 1924: 16.

Homochaetothrips Sakimura, 1968: 59 . Type species Pseudothrips parvus Bagnall, 1916 , by original designation. Synonym in Mound & Palmer, 1981: 164.

The genus Pseudanaphothrips was first proposed, with no included species, in a key to Thysanoptera genera ( Karny 1921). The genus was subsequently validated ( Karny 1924) by the inclusion of the single species Pseudothrips achaetus Bagnall from Australia. It remained monobasic for many years, diagnosed by the absence of long setae on the pronotum ( Fig. 7 ) and the presence of two complete rows of setae on the fore wing ( Fig. 6 ). Sakimura (1968) erected Homochaetothrips to include a series of seven species each of which bore two pairs of moderately prominent pronotal posteroangular setae ( Fig. 8 ); five of these species he transferred from Isochaetothrips , with one from Pseudothrips and the seventh as a new species. The outer pairs of pronotal posteroangular setae are commonly shorter than the inner pairs, and both pairs vary in length amongst the species assigned to Homochaetothrips . For example, the length of the outer pair varies from 25 to 60 microns between species. All seven species share with P. achaetus a range of structural character states as well as their Australian country of origin. Homochaetothrips was therefore placed into synonymy with Pseudanaphothrips by Mound and Palmer (1981), together with a full generic diagnosis. All eight species included here seem to be associated with flowers or inflorescences of various plant species. Most importantly, Mound and Palmer recognized that females of all these species bear laterally on abdominal tergites VI–VII, patches of irregular microtrichia that are sometimes arranged into a pair of ill-formed ctenidia. On tergite VIII these ctenidia are more clearly defined and are situated anterolateral to the spiracles ( Figs 27–34 ).As indicated above, these character states among Pseudanaphothrips species, together with the three pairs of ocellar setae and the chaetotaxy of the metanotum and fore wing, place this genus as a member of the Frankliniella genus-group.

Generic diagnosis: Antennae 8-segmented, III & IV with forked sense cone. Head wider than long, with three pairs of ocellar setae, ocellar setae pair III arising within ocellar triangle and usually between anterior margins of hind ocelli, never longer than distance between two ocelli. Pronotum transverse, usually with two pairs of prominent posteroangular setae, but one species with these setae no longer than the rest of the seven posteromarginal setae; anterior margin usually without any setae longer that discals. Metanotum with median setal pair arising at anterior margin, paired campaniform sensilla usually present near posterior margin; sculpture lines usually long and parallel, varying to weakly reticulate in some species. Fore wing with both longitudinal veins bearing complete row of setae. Tergites VI–VII laterally with irregular row of microtrichia sometimes forming a weakly developed ctenidium; tergite VIII laterally with pair of ctenidia more clearly defined, anterolateral to spiracles; VIII posteromarginal comb usually well developed, with median microtrichia often forming a more closely spaced group. Male similar to, but smaller than, female, sternites III–VII each with oval to transverse pore plate.

Key to species of Pseudanaphothrips

1. Pronotum with posteroangular setae scarcely longer than the other marginal and discal setae ( Fig. 7 ); posteromarginal comb on tergite VIII with small median group of microtrichia and lateral thirds of margin with few microtrichia ( Fig. 27 )... achaetus

-. Pronotum with 2 pairs of posteroangular setae more prominent than other setae ( Figs 5, 6 ); tergite VIII comb developed fully across posterior margin, microtrichia sometimes evenly spaced but sometimes with median microtrichia forming a discrete closely spaced group ( Figs 25–34 )....................................................................... 2

2. Female abdominal tergite X long, at least 1.3 times as long as IX and at least 1.3 times as long as basal width ( Fig. 28 ).... 3

-. Female abdominal tergite X scarcely longer than IX and with length about equal to basal width ( Figs 32, 33 )............. 4

3. Body and antennal segment I largely yellow, fore wings pale; abdominal segment X about 2.0 times as long as tergite IX ( Fig. 31 )........................................................................................... aureolus

-. Body and antennal segment I uniformly brown, fore wings brown; abdominal segment X about 1.8 times as long as tergite IX ( Fig. 34 )..................................................................................... uniformis

4. Metanotal median striae irregular posteromedially, almost reticulate in arrangement ( Fig. 20 )......................... 5

-. Metanotal median striae converging and close together posteromedially ( Figs 18, 19 )............................... 6

5. Ocellar setae III as long as width of antennal segment I; pronotal am setae clearly longer than longest discal seta. araucariae

-. Ocellar setae III shorter, no more than 0.6–0.8 as long as width of antennal segment I; pronotal am and pm setae all equally small....................................................................................... casuarinae

6. Body yellow, antennal segment II yellow to brownish yellow, not darker than III; tergite VIII marginal comb with microtrichia uniformly spaced or with a few medially slightly converging ( Figs 30, 31 )................................. frankstoni

-. Body light to dark brown, paler when teneral, antennal segment II brown and darker than III; tergite VIII marginal comb with median group of microtrichia closely spaced ( Figs 32, 33 )..................................................... 7

7. Antennal segments III–V largely yellow, sometimes also basal third of VI ( Fig. 8 ).............................. parvus

-. Antennal segment III yellow, but IV–V brown to dark brown ( Fig. 9 )........................................ querci

Figures

FIGURES 1–9. Pseudanaphothrips species. (1) Steele (1940) frankstoni type slide (2) pallidus type slide; (3) frankstoni syntype; (4) pallidus syntype; (5) querci holotype; (6) achaetus fore wing. Head & pronotum 4–6: (7) achaetus; (8) frankstoni; (9) parvus.

FIGURES 27–34. Pseudanaphothrips species, tergites IX–X. (27) achaetus; (28) aureolus; (29) araucariae; (30) frankstoni from Dicksonia; (31) frankstoni from Nothofagus; (32) parvus; (33) querci; (34) uniformis.

FIGURES 18–26. Pseudanaphothrips species, meso & metanota. (18) achaetus 1; (19) achaetus 2; (20) araucariae; (21) aureolus; (22) casuarinae; (23) parvus; (24) frankstoni from Dicksonia; (25) frankstoni from Nothofagus; (26) querci.