Nilotanypus prieuri, Published, 2007

Published, First, 2007, Chironomid midges from early Eocene amber of France (Diptera: Chironomidae), Zootaxa 1404, pp. 1-66 : 20-22

Nilotanypus prieuri n. sp.

( Figs. 16 –18)

Etymology: This species is named for Abel Prieur, a friend of the first author.

Diagnosis: No R 2+3; rather reduced venation with main veins ending well basal to wing apex; 1 mid and hind tibial spur, both long and curved, with no or very reduced lateral teeth; dorsomedial extension of eye with 5 ommatidia at apex; no weavy setae in apical third of terminal flagellomere.

(scale bar = 0.1 mm).

Description: Male head deformed, 0.37 mm long; ocelli absent; antenna 0.63 mm long, much longer than head, distinctly hairy, with 14 flagellomeres with long setae (shortest 0.01 mm long, longest 0.28mm long), pedicel broad and short, with 2 setae; 13 th flagellomere very long, 0.31 mm long, 14 th with distinctly apical nipple, with subapical seta; eye bare but deformed, with strong apically expanded dorsomedial exptention, with 5 ommatidia at apex; all palpomeres with few setae, no frontal setae, 2 postocular setae, inner vertical and outer vertical setae not visible, probably absent. Thorax 0.52 mm long, 0.4 mm wide, more than 0.7 mm high; scutellum, postnotum and scutal tubercle not visible; supraalar and prealar setae not visible; few anterior acrostichal and dorsocentral setae, preepisternum bare. Wing macropterous, 1.07 mm long, 0.27 mm wide, hyaline, without macrotrichia; anal vein An 2 absent; radius with 2 branches R 1 and R 4+5, R 2+3 absent; costa not produced after last branch of radius and ending before apex of wing; only M 1+2 and M 3+4 present; cross­vein MCu present. Halter 0.17 mm long. Fore femur 0.42 mm long, tibia 0.47 mm long, tarsus 0.91 mm long, mid femur 0.45 mm long, tibia 0.43 mm long; tarsus 0.8 mm long, hind femur 0.36 mm long, tibia 0.46 mm long, tarsus 0.93 mm long; only 1 mid and hind tibial spur, both very long and curved, with no or very reduced lateral teeth; ta4 cylindriform; hind tibial comb of 1 row. Abdomen 1.23 mm long, 0.66 mm wide; gonostylus elongate and narrow, 0.06 mm long, 0.008 mm wide; gonocoxite with long setae on outer surface, 0.08 mm long, 0.06 mm wide; anal point broad and conical, 0.04 mm long, 0.06 mm wide at base.

Discussion: In the key to dipteran families of McAlpine (1981), this fossil falls in the Tanypodinae . In the keys to Nearctic tanypodine tribes and genera of Fittkau (1962) and Oliver (1981) and the key to Holarctic genera of Murray & Fittkau (1989), Nilotanypus prieuri n. sp. falls in the Pentaneurini because of the following characters: tarsomere 4 of all tarsi cylindrical; FCu proximal to or opposite MCu; costa not produced after the last branch of the radius; no posterior anepisternals or preepisternals, and posnotum always bare. Nilotanypus prieuri is in a group of recent genera having a wing without R 2+3 and with a rather reduced venation with the main veins ending well basal of the wing apex, i.e., Nilotanypus Kieffer, 1923 , Monopelopia Fittkau, 1962 , Schineriella Murray & Fittkau, 1988 , and Labrundinia Fittkau, 1962 . Labrundinia has very reduced tibial spurs, unlike N. prieuri . Schineriella has two mid­tibial spurs instead of one, as in N. prieuri . The tibial spurs of N. prieuri are similar to those of Nilotanypus and Monopelopia . The dorsomedial extension of the eye of Monopelopia is slightly tapered with only two ommatidia at the apex, instead of five, as in N. prieuri and Nilotanypus . Also, N. prieuri has no wavy setae on the apical third of the terminal flagellomere, unlike Nilotanypus . We provisionally place N. prieuri in Nilotanypus .

Material: Holotype PA 428 1/2, (male).