Neocecidothrips pacificus (Bianchi) Mound & Goldarazena, 2022

Mound, Laurence A. & Goldarazena, Arturo, 2022, Antennal sense cone variation in Teuchothrips species of New Caledonia, with one new generic combination (Thysanoptera, Phlaeothripinae), Zootaxa 5124 (2), pp. 238-244 : 241-242

Neocecidothrips pacificus (Bianchi) comb.n.

( Figs 6‒12 )

Arrhenothrips pacificus Bianchi, 1952: 385 .

This species was described from three females and three males, taken in New Caledonia at Bois du Sud, July 1950, from the rolled leaves of an undetermined plant. The descriptive notes below are based on the holotype female that was studied in Canberra, on loan from the Bishop Museum, Hawaii. The genus Arrhenothrips was erected by Hood (1919) for a single species that he described from India as ramakrishnae. That species has the typical antennal sense cone formula of members of the Liothrips lineage, 1 on III, 3 on IV, but both sexes have a stout fore tarsal tooth and females have the fore femora enlarged. However, the relationships of this genus require further study, including a further four species from India and two from Africa that were subsequently included ( ThripsWiki 2021). The species considered here from New Caledonia seems unrelated to ramakrishnae in having two stout sense cones on antennal segments III and IV, and antennal segment VIII elongate and narrowed to the base. Moreover, contrary to the description by Bianchi, the fore femora are not particularly enlarged, and the fore tibial inner apex is simple and does not have “a broad tubercle-like distal production” ( Fig. 7 ). The elongate antennal segment VIII of pacificus ( Fig. 8 ) is similar to Litotetothrips species ( Mound & Tree 2021), but the maxillary stylets are deeply retracted and close together ( Fig. 6 ). The species is here referred to Neocecidothrips , because the two known species of that genus ( Mound 2008) are the only members of the Teuchothrips -group that share a similar antennal sense cone formula.

Descriptive notes: Antennae 8-segmented, segments III‒VI each with 2 stout sense cones, on III both sense cones 0.7 as long as width of segment; VII sharply narrowed to base but neck not as distinct as on VI; VIII slender and narrowed to base. Head posterior to postocular setae with faint narrowly transverse reticulate lines of sculpture; maxillary stylets long, retracted to posterior margin of eyes and close together medially ( Figs 6, 10 ). Pronotum without sculpture lines medially ( Fig. 11 ); all five pairs of major setae capitate but anteromarginals weakly capitate and 35 microns long; anteroangulars 60, epimerals 105; notopleural sutures complete. Basantra absent ( Fig. 12 ); ferna transverse but not meeting medially; mesopresternum of paired lateral triangles with a weak median sclerite anterior to mesosternal margin; metathoracic sternopleural sutures present but not long. Metanotum reticulate on posterior half but very weakly sculptured on anterior half ( Fig. 9 ). Pelta broadly triangular, with pair of CPS. Tergite IX setae S1 capitate and shorter than tube.

Figures

FIGURES 5–12. Teuchothrips and Neocecidothrips. (5) T. ornatus head (LAM5607). N. pacificus holotype 6–12: (6) head; (7) fore tibia & tarsus; (8) antenna; (9) mesonotum, metanotum & pelta. (10) head & pronotum; (11) pronotum; (12) prosternum.