Macrochile hornei Krzeminski

Krzeminski, Wiesław, Krzeminska, Ewa, Kania, Iwona & Ross, Andrew J., 2013, New taxa of Tanyderidae (Diptera) from Eocene Baltic amber, Zootaxa 3599 (1), pp. 59-66 : 60-64

Macrochile hornei Krzeminski sp. nov.

( Figs. 5–14 )

Diagnosis. R2+3 equal Rs and almost half of R2; base of d cell twice longer than M3; gonostylus with one process in basal part and wide, oval swelling in middle part of gonostylus, covered with strong bristles.

Etymology. In honor of the late Mr. Eric Horne, who donated the holotype to the Natural History Museum, London.

Type material. Holotype: No. NHM.PI. II.2527 (male), housed in the Natural History Museum, London. Baltic amber, Upper Eocene; Paratype: No. 7110 (male) Górski coll.; No. 1/1/99 (male) Kupryjanowicz coll.; No. 1024-3 (male), No. 1613-2 (male) Hoffeins coll.; No. MP/2919 (female), No. MP/2917 (female) Institute of Systematic and Evolution of Animals, Polish Academy of Sciences, Kraków.

Description. Head: eye with pubescence similarly to other species of Macrochile from Baltic amber; antenna ( Fig. 6 ) 18-segmented; scape twice longer than wide; pedicel about as long as wide; first flagellomere 1.5 times longer than second; most flagellomeres nearly cylindrically shaped, with two long verticils; last segment c. 1.3 times longer than penultimate; palpus ( Fig. 5 ): last segment 1.5 times longer than penultimate. Thorax dark brown.

Wing 6.1 mm long ( Figs 7, 8 ). Wing ( Fig. 7 ) slightly brown infuscate with very small darker marks in outlets of veins R2+3, R4+5, M4 and Cu. Sc ending opposite fork of R4+5 into R4 and R5; R2+3 as long as Rs; R2+3 c. 1.75 times longer than R2; M1 twice longer than M1+2 (i. e., upper part of d cell); base of d cell twice longer than remainder of M3 ( Fig. 8 ); A2 forming characteristic loop with very well visible cross-vein between anal loop and A1. Leg: fore leg with single apical spur ( Figs 9, 10 ), mid and hind leg with two spurs. Abdomen: tergites and sternites dark brown banded, with proximal part being darker than distal. Hypopygium: 8th abdominal segment distinctly narrowed, 9th segment constricted into narrow ring with additional triangular lobe; gonocoxite ( Fig. 11 ) short and rather wide, gonostylus with big protuberance provided with strong, short bristles; aedeagus trifid ( Figs 12 , 14 ).

Remarks. The wing venation of the new species is very similar to that of Macrochile spectrum ( Figs 1, 2 ), but the discal cell is longer and gonocoxite and gonostylus of both species are quite different (compare Figs 3, 4 and 12 ). The gonostylus of M. hornei is narrow, slightly curved at the top, and with flat, wide lobe provided with strong, short bristles.

Figures

FIGURES 5 – 12. Macrochile hornei Krzeminski sp. nov., Holotype No. NHM. PI. II. 2527; 5. palpus, 6. antenna, 7. wing, 8. wing, reconstruction (oryg.), 9. fore leg, 10. fore leg, reconstruction, 11. hypopygium, ventrolateral view, 12. gonocoxite and gonostylus, ventral view, reconstruction (oryg.); (abbreviations as in Fig. 1 – 4).

FIGURES 13 – 14. Macrochile hornei Krzeminski sp. nov., Holotype No. NHM. PI. II. 2527. 13. dorsal view, 14. male terminalia, ventrolateral view, reconstruction (oryg.); (abbreviation as in Fig. 1 – 4).

FIGURES 1 – 4. Macrochile spectrum Loew, 1850, No. K 17492246; 1. wing, 2. wing, drawing (oryg.), 3. hypopygium, ventrolateral view, 4. gonocoxite and gonostylus, ventral view, drawing (oryg.); a—arm of gonostylus; a. l. — anal loop; gs—gonostylus; gx—gonocoxite; k—knob on gonostylus.