Paralleloalathrips bivenatus, Ulitzka, 2022

Ulitzka, Manfred R., 2022, New genera and species of Rohrthripidae (Thysanoptera: Tubulifera) from Burmese Cretaceous amber, Zootaxa 5162 (1), pp. 1-36 : 9-11

Paralleloalathrips bivenatus gen. et sp. n.

( Figs 8–11 )

Female (Holotype). Body ( Fig. 8 ) fully distended; pterothoracic tergites deformed and translucent, therefore their features difficult to assess; legs folded under body with exception of right hind leg; wings spread, hind wings lying in front of fore wings.

Colour ( Figs 8–9 ) uniformly dark brown including antennae and legs; all major setae dark as well as wing veins and fringes; fore wings ( Fig. 10 ) shaded greyish-brown, hind wings lighter with a dark median streak.

Head ( Figs 8–9 ) wider than long, recessed behind the eyes, with cheeks slightly rounded in front, but almost straight and parallel towards base; cheeks with some sparse and weak setae; ocellar setae difficult to assess, one short pair clearly visible as well as the points of attachment of a second pair near the base of antennae. Eyes small, not prolonged ventrally. Hind ocelli close to compound eyes; far apart from each other; fore ocellus far in front between the antennal insertions. Antennae nine-segmented ( Fig. 8 ); segment I barrel-shaped; II inversely conical, apically with a small circular sensorium; III–VII inverse conically shaped and tapering distally from level of sense cones; VIII spindle-shaped; IX style-shaped, at base much narrower than VIII distally. Outer sense cones stout, inner ones smaller; their number difficult to assess but at least one inner and one outer on III–VI and one outer on VII. Mouth cone short and rounded. Maxillary palps two-segmented; with three apical setae. Pronotum wider than long; pronotal chaetotaxy not assessable; most likely with two pairs of posteroangular setae, all of which are faint but long and pointed. Pterothorax dorsally as well as pelta not assessable. Fore wings ( Fig. 10 ) straight and narrow, with fore and hind margin parallel between clavus and tip; tip softly pointed; anterior and posterior vein complete; both veins bearing 4–5 setae; membrane without microtrichia. Fringe cilia straight; arising from sockets. Duplicated cilia present around wing tips and apical margins of fore wing; with only a few cilia present at the fore margin; and about 14 cilia at hind margin attached in an angle towards the body. Clavus with paired setiform processes at tip. Hind wing without microtrichia and without any veins; base with one recurved seta. Fore legs ( Fig. 8 ) with femora not enlarged; tibiae terminally with a strong spine-like seta; fore tarsi without teeth but with a small recurved hamus. Mid and hind legs slender; tibiae each with a long dorsal seta and terminally with at least one strong spine; mid and hind tarsi two-segmented. Abdominal tergites without wing-retaining setae; short mid-dorsal setae visible on tergites III–V; lateral setae weak, slightly curved and pointed. Abdominal segment IX dome-shaped; setae s1 curved upwards and stronger than s2 and s3; s3 longest, but somewhat shorter than tube. Abdominal segment X elongated tubular, with a terminal crown of anal setae, which are shorter than the tube ( Fig. 8 ).

Measurements. Female MU-Fos-125/1 (in microns): Body, length 1225. Head, length 151; width 207. Eyes, length 56; width 40. Hind ocelli, diameter 16; distance between the hind ocelli 68. Ocellar setae not measurable. Pronotum, length 152; width 233; posteroangular setae about 75. Pterothorax, largest width 267. Abdomen, length 804; largest width 310 (segment III); segment X (tube), length 143; basal width 47. Setae s3 on tergite IX 140. Antennae, length 327; length (largest width) of segment I 31 (37), II 31 (22), III 48 (31), IV 37 (22), V 43 (25), VI 40 (22), VII 40 (19), VIII 37 (11), IX 20 (3). Sense cones, length of inner (outer) on segment III 16 (20), IV 14 (20), V 12 (16), VI – (12), basal width of inner (outer) about 2 (4). Fore wings, length 696; width in the middle 40.

Male (Paratype). Body fully distended; head slightly compressed; antennae inclined to the right; wings spread, but right hind wing bent forwards; legs spread except for right fore leg; thorax and basal segments of abdomen ventrally hidden by a large bubble of air.

Similar to female in colour and body structure; somewhat larger. Fore femora slightly enlarged. Pronotum with two pairs of long posteroangular setae. Pelta broad; abdominal tergite II with a pair of distinct dorsolateral sutures slanting posteriorly inwards ( Fig. 11 ). Abdominal sternite IX with hypandrium and androsternite (see Bhatti 1998b); X ventrally at base with a triangular recess (see Priesner 1968).

Measurements. Male MU-Fos-149/1 (in microns): Body, length 1401. Head, length 176; width 220. Pronotum, length 163; width 258; inner and outer posteroangular setae about 80. Abdomen, length 850; largest width 346 (segments III and IV); segment X (tube), length 151; basal width 51. Antennae, length 365. Fore wings, length 835; width in the middle 50.

Material studied. The holotype female MU-Fos-125/1 ( Figs 8, 10 ) and the paratype female MU-Fos-133/1 have been donated to the author by Patrick Müller; the paratype female MU-Fos-124/1 ( Fig. 9 ) as well as the paratype male MU-Fos-149/1 ( Fig. 11 ) were purchased by the author on eBay from Terry Su, eBay username “burmiteminer”. All specimens are inclusions in Burmese amber and originate from mines in the Hukawng Valley , Kachin State, Myanmar. The holotype and all paratypes are deposited in the collection of the author .

Syninclusions. MU-Fos-124/1: about 30 fungal spores around the left antenna of the thrips ( Fig. 9 ), one mite, plant detritus as well as some stellate plant hairs, tiny droplets and many cracks limiting the visibility of the thrips; MU-Fos-125/1: a beetle ( Coleoptera , Staphylinidae , Scydmaeninae ), remnants of two insect legs, a mite, plant detritus and some pyrite crystals close to the thrips; MU-Fos-133/1: one midge, many tiny droplets; MU-Fos-149/1: bubbles of air and some tiny brownish droplets.

Etymology. The species epithet bivenatus comes from the Latin prefix bi, meaning “two”, and the Latin word venatus, meaning “with veins”. It refers to the two complete wing veins of this species ( Fig. 10 ).

Figures

FIGURES 8–11. Paralleloalathrips bivenatus gen. et sp. n. (8) holotype female, dorsal view, fore wings indicated; (9) paratype female, indicated: fungal spores; (10) holotype female, left fore wing; (11) paratype male, basal abdominal tergites, indicated: dorsolateral grooves on tergum II (met: metanotum, pt: pelta, mpII: medial plate of tergum II, lpII: lateral plate of tergum II, III: tergum III).