Dilychnia, MOTSCHULSKY, 1854

GENUS DILYCHNIA MOTSCHULSKY, 1854 View in CoL

( FIGS 4–20, 22–34, 36–38)

Dilychnia Motschulsky, 1853: 30 View in CoL (description [desc.]); Lacordaire, 1857: 319 (systematics [syst.]); Gemminger, 1870: 119 (catalog [cat.]); Kirsch, 1873: 390 (desc.); Olivier, 1911: 72; 1912: 171 (syst.); McDermott, 1966: 73 (cat.).

Lucidota Laporte, 1833 View in CoL (partim); Gemminger & Harold, 1869: 1639 (synonyms [syn.]); Olivier in Wytsman, 1907: 20 (syn.); Blackwelder, 1945: 353 (cat.). Type species: Dilychnia basalis Motschulsky, 1853 by original designation, currently placed in synonymy with Dilychnia guttula ( Fabricius, 1801) View in CoL .

Diagnosis: Antennal flagellum densely bristled ( Fig. 6G), clypeus connate and co-planar with frons ( Fig. 6E), pronotum with posterior margin conspicuously bisinuate ( Fig. 7A), elytral secondary pubescence absent ( Fig. 18A–C). Male with sternum VIII mucronate ( Fig. 9E), paramere with elongate projections ( Fig. 9G–I), phallus with struts longer than basal plate of the paramere and phallobase symmetrical ( Fig. 9G).

lateral margins pale yellow ( Fig. 11A–C). Abdomen dark brown ( Fig. 22C) or basally yellow–orange, progressively black posteriad ( Fig. 29B).

Head: Completely covered by pronotum ( Fig. 22A), hypognathous ( Fig. 22C), clypeus connate to frons, emarginate anteriad, 2× wider than long ( Fig. 6E). Mandible stout basally, proximal region with a fringe of bristles, apex thin ( Fig. 6A), crossed in frontal view ( Fig.6E). Maxilla with galea thin and covered by bristles ( Fig. 6A), lacinia medially fused, internal margin with a thick fringe of bristles; palpifer rectangular; palpi four-segmented ( Fig. 6A).

Description of male

Coloration: Antenna entirely dark brown ( Fig. 6G). Prothorax entirely light orange or yellowish brown, central region slightly darker ( Fig. 7). Elytron brown– orange ( Fig. 13A, B) or dark brown ( Fig. 12A–C), sometimes with basal one-third ( Fig. 18A–C) or with Thorax: Pronotum with anterior margin coarsely punctured, central region biconvex, anterior and lateral margins slightly concave, posterior margin with posterior angles projected posteriad ( Fig. 7A). Hypomeron trapezoidal, ventral margin medially projected downwards ( Fig. 7E). Scutellum triangular, slightly truncate posteriad ( Fig. 25A). Mesosternum sclerotized, acuminate posteriad and attached to metasternum by a sclerotized suture ( Fig. 25D). Metasternum slightly depressed by the mesocoxae, anterior medial keel distinct, weakly developed, almost as long as one-quarter of sternum length ( Fig. 25B–D); lateral margin convex, divergent up to half its length. Mesosternum/mesanepisternum suture indistinct ( Fig. 25D). Mesepimeron attachment to metasternum coriaceous ( Fig. 25C). Metasternum slightly wider than long and posterior margin strongly emarginate ( Fig. 25B). Elytron slightly convex ( Fig. 18A–C), feebly convergent at apical third, rounded at apex. Hind wing well developed, posterior margin sinuose, 2× longer than wide; costal row with setae inconspicuous; CuA2 absent, MP-Cu present; RP + MP 1 + 2 three-quarters as long as

856 S. VAZ ET AL.

r4, almost reaching distal margin, J as long as RP + MP 1 + 2 ( Fig. 18D). Legs with metafemur slightly narrower than pro- and mesofemora, tibia with outer margin covered by short setae ( Fig. 8), tarsomere I with lateral margin straight and 1.5× longer than II, pro- and mesotarsomere dorsally indented; II 2× longer than III; III annular; IV bilobate with pilose pad, claws simple ( Fig. 8).

Abdomen: Seven visible sterna (II–VIII), lateral margins divergent posteriad, spiracles dorsal ( Fig. 9B); sterna VIII wider than long, posterior margin mucronate ( Fig. 9E); pygidium sclerotized, posterior margin with two parasagittal sinuosities ( Fig. 9D); sternum IX subtriangular ( Fig. 9F).

Aedeagus: Phallobase symmetrical ( Fig. 9G); parameres symmetrical and apex acute, and with projection membranous ( Fig. 9G); phallus extending basally beyond paramere; ventral plate with lateral margin sinuose, fused basally and strongly sclerotized ( Fig. 9H–I).

Description of female

Eyes slightly smaller than frons width; sternum VI with light organ smaller than in males, usually one-third of the width of the sternum; sternum VII with light organ slightly smaller than light organ of sternum VI, but absent in D. guttula and D. disparilis ; sternum VIII with lateral margins converging posteriad and posterior margin with median region emarginate; pygidium with posterior margin with parasagittal sinuosities and a median region slightly rounded. Genitalia with one rounded spermatheca and a large spermatophore-digesting gland; ovipositor with styli apically sclerotized and bristled outwards at the lateral edges.