Chimeromyia alava Arillo & Grimaldi

Grimaldi, David A., Cumming, Jeffrey M. & Arillo, Antonio, 2009, Chimeromyiidae, a new family of Eremoneuran Diptera from the Cretaceous, Zootaxa 2078, pp. 34-54 : 48

Chimeromyia alava Arillo & Grimaldi , sp. n.

( Figs. 11 , 12 )

Diagnosis. Similar to C. pilitibia in having crossvein bm-cu slightly proximal to r-m and the male terminalia with a lobed surstylus, but differs by having the surstylus shorter and being trilobed instead of bilobed, R2+3 is shorter and curved more abruptly costad, and the male hind tibia without a brush of long, fine setae.

Description. Body length 1.0– 1.45 mm. HEAD: Eyes large, bare, facets not differentiated. Two pairs long ocellar setae present; ocelli on small raised tubercle. Arista situated dorsally on flagellomere one; arista with three articles, basal two very small. Vibrissae present. THORAX: Bristly, with notopleural and supra-alar setae present. Acrostichals in short, single row; one pair of dorsocentals. Scutellum with 2 pairs setae, apical pair longer (this pair cruciate in MCNA 8883). Legs bristly, but without brushes on tibiae or tarsi. Wing: Sc vestigial; C extended to slightly past apex of vein M1; R1 meeting C at slightly less than length half length of wing; R2+3 strongly curved toward and meeting C, distances between apices of R1 and R2+3 only ca. 1/2 length of vein R1 from where it forks with R2+3; vein R4+5 forked with R4 and R5 widely divergent, at nearly a right angle; crossveins bm-cu slightly proximal to r-m, separated by distance ca. 0.3x length of r-m; M1 straight, nearly parallel to R5; base of vein M2 absent, M2 not reaching wing margin; CuA1 straight, complete apically. Anal lobe reduced. ABDOMEN: Male terminalia: Fused cerci with pointed apex; epandrium with row of stiff setae on dorsoapical margin; surstylus with three lobes (two lateral ones, one longer, thin mesal one), setulae at apex of only lateral lobes; phallus apically scoop-shaped, slightly S-shaped; postgonites with apex having minute denticles on ventral surface; hypandrium obscured. Female genitalia (MCNA 9318) with cercus large and ovoid in lateral view.

Types. All Specimens from SPAIN: ÁLAVA : Peñacerrada, Escucha Formation, Early Cretaceous. Holotype, male, MCNA 9238 (body length 1.45 mm, wing 1.05 mm), with genitalia well preserved. Paratypes: female, MCNA 9318, genitalia well preserved but head and thorax badly preserved (body length 1.25 mm, wing 1.1 mm); male/female, MCNA 8883, a very small specimen (1.00 mm body length), but with venation identical to others in type series; MCNA 8743.2 female, the venation identical to other specimens of C. alava ; female, MCNA 8886, head is very distorted and gives an appearance of the arista not being dorsal, venation also identical to others in type series (body length 1.45 mm). All deposited in Álava Museum of Natural Sciences, Vitoria-Gasteiz, Spain.

Etymology. Taken directly from Álava , Basque Country of Spain.

Figures

FIGURE 12. Chimeromyia alava, n. sp., in Spanish amber. A, B, D. Holotype male, MCNA 9741. A. Head, oblique frontal view. B. Male terminalia, left lateral view. C. Wing, MCNA 9238, paratype. D. Wing, showing preserved venation of holotype.

FIGURE 11. A – D: Chimeromyia alava, n. sp., in Spanish amber, photomicrographs. A. MCNA 9238 (holotype), dorsal habitus. B. MCNA 8883, dorsal habitus of incomplete specimen. C. MCNA 9318. Oblique dorsal habitus. D. MCNA 8886, left lateral habitus. E: Chimeromyina concilia, n. gen., n. sp. MCNA 8882 (holotype), dorsal view of head and thorax.