Gemineurothrips, Ulitzka, 2022

Ulitzka, Manfred R., 2022, New genera and species of Rohrthripidae (Thysanoptera: Tubulifera) from Burmese Cretaceous amber, Zootaxa 5162 (1), pp. 1-36 : 5-6

Gemineurothrips gen. n.

Type species: Gemineurothrips microcephalus gen. et sp. n.

Diagnosis. Abdominal segment X tubiform, without a ventral median suture, but with a crown of apical anal setae. Antennae ( Fig. 4 ) nine-segmented. Maxillary stylets lowly retracted into the head and wide apart ( Fig. 36 ). Fore wings ( Fig. 7 ) becoming progressively larger in distal half; with two parallel wing veins; both furnished with stout setae; cross-veins not developed. Fringe cilia at fore wings mainly retracted into the wing membrane, at hind wings partly arising from sockets; duplicated cilia present around wing apex ( Fig. 29 ). Fore wing clavus with paired setiform processes at tip and hind wing with basal recurved setae, wing coupling hamulo-frenate ( Fig. 26 ). Abdomen without wing retaining setae. Fore tibiae with a strong distal spine. Anal setae much shorter than tube ( Fig. 5 ).

Gemineurothrips shows character states of modern Tubulifera combined with plesiomorphic features like ninesegmented antennae and fore wings with two complete veins; it therefore is allocated to Rohrthripidae . Furthermore, wing coupling in Gemineurothrips is hamulo-frenate as it is in Rohrthrips ( Fig. 25 ). Members of both genera have broadened wings; this feature distinguishes both from other Rohrthripidae . Gemineurothrips differs from Rohrthrips in having a complete second wing vein bearing stout setae ( Fig. 7 ). Furthermore, the maxillary stylets are deeply retracted into the head capsule and close together in Rohrthrips (see Ulitzka 2018), whereas they are low in the head only and far apart in Gemineurothrips ( Fig. 36 ). Finally, the pronotal chaetotaxy is different, with well-developed posteromarginal setae and a second pair of (much shorter) posteroangular setae in Gemineurothrips , whereas in Rohrthrips the posteromarginal setae are vestigial and only one pair of posteroangular setae is present.

Etymology. The name of the new genus derives from the Latin word geminus, meaning “twin”, the Greek word νεῦρΟν (neuron), meaning “vein”, and thrips, the usual term for a genus within Thysanoptera . It refers to the almost identical wing veins lying as “twins” in the fore wings of the generic type specimen ( Fig. 7 ).

Figures

FIGURES 1–4. Rohrthripidae species. Adstrictubothrips mirapterus gen. et sp. n. 1–2: (1) holotype female dorsal view, indicated: constriction at the tube; (2) right wings, indicated: duplicated cilium on fore wing margin. Gemineurothrips microcephalus gen. et sp. n. syntype female (MU-Fos-145/1) 3–4: (3) dorsal view; (4) left antenna.

FIGURES 35–38. Line drawings of Rohrthripidae. Head, mouthparts and prothorax (md: mandibula, mx: maxillary stylets) 35–37: (35) Adstrictubothrips mirapterus gen. et sp. n. holotype female; (36) Gemineurothrips peculiaris gen. et sp. n. holotype (spa: posteroangular setae, left broken off and lying close to coxa; scx: coxal setae); (37) Rohrthrips rhamphorhynchus sp. n. holotype. (38) Rohrthrips multihamuli sp. n. holotype; left antenna, segment numbers in Roman numerals, indicated: ventral projections on segments V–VII (cs: campaniform sensillum, uncolored trichomes indicate presumptive sense cones).

FIGURES 5–7. Rohrthripidae species. (5) Gemineurothrips microcephalus gen. et sp. n. syntype female (MU-Fos-148/1): dorsolateral view. Gemineurothrips peculiaris gen. et sp. n. holotype 6–7: (6) dorsal view; (7) left fore wing.

FIGURES 24–29. Thysanoptera wings. Wing coupling (f: frenulum, h: hamuli, r: retinaculum, smr: submarginal ridge, indicat- ed: microtrichia) 24–27: (24) Taeniothrips inconsequens Uzel (Terebrantia: Thripidae); (25) Elaphrothrips cf. costalimai Hood (Tubulifera: Phlaeothripidae: Idolothripinae); (26) Gemineurothrips microcephalus gen. et sp. n. (Tubulifera: Rohrthripidae); (27) Rohrthrips multihamuli sp. n. (Tubulifera: Rohrthripidae). Tubulifera fore wing duplicated cilia (green to red arrow: area with duplicated cilia) 28–29: (28) Haplothrips setiger Priesner (Phlaeothripidae); (29) Gemineurothrips microcephalus gen. et sp. n. (Rohrthripidae).