Palaeopsilotreta cretacea, Wichard & Espeland & Müller & Wang, 2020

Wichard, Wilfried, Espeland, Marianne, Müller, Patrick & Wang, Bo, 2020, New species of caddisflies with bipectinate antennae from Cretaceous Burmese amber (Insecta, Trichoptera: Odontoceratidae, Calamoceratidae), European Journal of Taxonomy 653, pp. 1-17 : 9

Palaeopsilotreta cretacea sp. nov.

urn:lsid:zoobank.org:act:DD288746-197D-4F8E-A45E-75D1330D1C45

Fig. 3

Diagnosis

Antennae of males with 12 bipectinate flagellomeres and last two flagellomeres simple, not bipectinate. In male forewing, media branched in M1+2 and M3+4. In male genitalia, harpago apically with two clear thorn-like black spines. Palaeopsilotreta cretacea sp. nov. is clearly distinguished from P. xiai and P. burmanica sp. nov. by the branched media in forewings and by the harpago at an angle of 90° to the coxopodite. Palaeopsilotreta xiai and P. burmanica sp. nov. have the media unbranched, and the harpago and coxopodite form a straight unit.

Etymology

Palaeopsilotreta cretacea sp. nov. is named for the geological age of the amber.

Material examined

Holotype

MYANMAR – Kachin State • ♂; exact locality unknown; Mid-Cretaceous Burmese amber inclusion; former Patrick Müller collection, BUB 2883 ; ZFMK-TRI000814 . Body well preserved; forewing in dorsal view, hind wing covered dorsally by forewing. Antennae and legs present. Male genitalia visible in ventral view.

Description

HEAD. Light brown. Antennae partially bipectinate, consisting of long scapus, short pedicellus, and first flagellomere as long as pedicellus, both together about as long as scapus, followed by 12 successive bipectinate flagellomeres, and, finally, 2 simple flagellomeres without rami ( Fig. 3B ). Antennae about as long as forewings. Maxillary palps 5-segmented and labial palps 3-segmented, their terminal segments not flexible or annulate. Head dorsal ocelli absent, probably with interantennal, postantennal and posterior setose warts, but not well preserved and hard to recognize; scutum slightly macerated, scutellum shows single dome-shaped, large, ovoid wart.

FOREWINGS ( Fig. 3C ). Light brown, translucent, 2.6 mm long. Radius R1 running straight to apical wing margin. Forks I and II of Rs present, sessile, branching at same level. Discoidal cell closed by crossveins, DC smaller, about half as long as fork I, fork II. Media branching into M1+2 and M3+4. Fork M longer than fork I and fork II, reaching up to half length of discoidal cell. Medial and thyridial cells absent. Cu1 running straight, apically bifurcated into fork V (Cu1a – Cu1b); Cu2 simple, not forked, so far as visible, probably with crossvein to Cu1b. Anal veins probably complete. Hindwings light brown, translucent, relatively narrow, smaller than forewings, about 2.1 mm long, so far as visible, venation probably similar to forewing venation. Radius R1 straight, forks I, II present; M probably simple, without fork; Cu1 with relatively long fork V, Cu2 simple. [Generally, crossveins in hyaline wings are difficult or impossible to detect].

TIBIAL SPURS. 2/4/4.

MALE GENITALIA.Visible only in ventral view ( Fig. 3 D–E): Inferior appendages(gonocoxites)2-segmented. Coxopodites strong and slightly angular, broad at base, tapering towards apex, slightly curved towards genital centre, flanks more curved mesally than laterally. Harpago almost at right angle to coxopodites, directed centrad, rod-shaped, black, less than ¼ as long as coxopodites and much smaller in volume; apical end of harpago not clearly visible. Segment X apparently covering central phallic apparatus dorsally with 2 oblong scales. Lateral preanal appendages long, slightly bent inward.

Figures

Fig. 3. Palaeopsilotreta cretacea sp. nov. (ZFMK-TRI000814) A. Holotype male in dorsal view. B. Head with bipectinate antennae, maxillary palps and labial palps. C. Drawing of a forewing. D. Drawing of the male genitalia. E. Male genitalia in ventral view.