Iridothrips Priesner, 1940

Wang, Zhaohong, Mound, Laurence & Tong, Xiaoli, 2019, Phylogenetic relationships within the Frankliniella genus-group based on morphology, with a revision of Iridothrips (Thysanoptera, Thripidae), Zootaxa 4651 (1), pp. 141-154 : 145

Iridothrips Priesner

Iridothrips Priesner, 1940: 403 . Type species Bregmatothrips iridis Watson.

Pelikanothrips Bhatti, 1978: 189 . Type species Taeniothrips kratochvili Pelikan , by monotypy. Syn. n.

Previously comprising only two species, Iridothrips is a small genus from Europe in the Frankliniella genus-group with species living among the basal leaf-sheaths of grasses and similar plants in moist habitats ( Pelikan 1961; Jenser 2013a). Species in this genus are stated by zur Strassen (2003) to differ from Frankliniella species in having the sense cone on antennal segments III and IV simple. However, as indicated by illustrations in Mound et al. (1976) and Mound et al. (2018), the sense cones of iridis on these segments are sometimes Y-shaped, and this condition is relatively common amongst European specimens (Vierbergen pers. comm. 2018). Iridothrips species share many similarities with grass-living species of Frankliniella , such as head clearly projecting between eyes, and ocelli rather smaller. These similarities may be associated with similar living conditions on grasses. Within both Iridothrips and Frankliniella there are species that are micropterous or apterous, and in such individuals the metanotal median setae are generally behind the anterior margin, whereas macropterous individuals have the metanotal median setae at the anterior margin. The diagnostic differences between Iridothrips and Frankliniella are given in the key above. According to the morphological analysis results indicated above, Fr. zizaniophila, Pe. kratochvili and Iridothrips species form a monophyletic group, thus Pelikanothrips is placed as a synonym of Iridothrips , and F. zizaniophila is transferred to Iridothrips . This genus possibly represents a small Eurasian radiation derived from the American genus.

Generic diagnosis: macropterous or micropterous; head with wide projection in front of eyes, hind ocelli close to eyes ( Fig. 7 ); ocellar setae pair I present or absent, pair III well developed and situated on margin of ocellar triangle; eyes with 5 pigmented ommatidia; maxillary palps 3-segmented. Antennae 8-segmented, segment I without paired dorso-apical setae, III–IV with sense cone simple or forked ( Figs 27 & 28 ). Pronotum wider than long and medially without discal setae. Mesonotum with campaniform sensilla present. Metanotal median pair of setae at or behind anterior margin, campaniform sensilla absent. Mesosternum with sternopleural sutures complete, endofurca with or without spinula, metasternal endofurca without spinula. Fore wing slightly saber-shaped, posterior margin slightly more curved than front margin at apex, veinal setal rows complete but widely spaced ( Fig. 30 ); posteromarginal fringe cilia wavy; clavus usually with 3–4 veinal setae. Tarsi 2-segmented. Tergites V–VII posteroangular setae close to angle ( Fig. 21 ); tergites V–VIII with paired ctenidia, ctenidia on VI–VII ending anterior to minor setae S3, on VIII anterolateral to spiracles; IX with two pairs of campaniform sensilla. Sternites III–VII with three pairs of posteromarginal setae arising at posterior margin ( Fig. 38 ). Male sternites III–VII each with a pore plate ( Fig. 35 ).

Figures

FIGURES 2–12. Character states of Frankliniella genus-group. 2–7 head: (2) Fr. insularis; (3) Fr. schultzei; (4) Y. yangtzei; (5) I. mariae; (6) Ps. araucariae; (7) I. lobulatus. 8–12 head and pronotum: (8) Fr. zizaniophila; (9) Fr. williamsi; (10) S. calcaratus; (11) T. physapus; (12) P. achaetus. [see Appendix 1 for character state codes]

FIGURES 27–38. Character states of Frankliniella genus-group. 27–28 antennae: (27) I. lobulatus; (28) I. mariae. 29–30 fore wing: (29) Fr. schultzei; (30) I. lobulatus. 31–33 tergite VIII: (31) Fr. cephalica; (32) Fr. williamsi; (33) K. pisivorus. 34–35 male: (34) Fi. firmus tergites IX–X; (35) I. lobulatus sternites VII–VIII. 36–38 sternite VII: (36) Fr. intonsa; (37) T. physapus; (38) I. lobulatus. [see Appendix 1 for character state codes].

FIGURES 19–26. Character states on tergites: (19) Fr. tenuicornis IV–V; (20) Y. yangtzei V–VI; (21) I. lobulatus VII–VIII; (22) Pa. setifer VI–VIII; (23) T. physapus VII–VIII; (24) Ps. achaetus VII–VIII; (25) I. mariae VIII; (26) Fr. schultzei VII–VIII. [see Appendix 1 for character state codes].