Fabogethes Audisio & Cline, 2009

Audisio, Paolo, Cline, Andrew Richard, Biase, Alessio De, Antonini, Gloria, Mancini, Emiliano, Trizzino, Marco, Costantini, Lorenzo, Strika, Sirio, Lamanna, Francesco & Cerretti, Pierfilippo, 2009, Preliminary re-examination of genus-level taxonomy of the pollen beetle subfamily Meligethinae (Coleoptera: Nitidulidae), Acta Entomologica Musei Nationalis Pragae 49 (2), pp. 341-504 : 391-394

14. Fabogethes Audisio & Cline , gen. nov.

( Figs. 14 a–h )

Type species. Meligethes nigrescens Stephens, 1830: 47 (by present designation) [= Fabogethes nigrescens ( Stephens, 1830) comb. nov.].

Generic description and diagnosis. Inclusive species vary greatly in size (1.7–3.0 mm length), and share the following combination of characters.

Body color and pubescence: pubescence silvery-whitish to golden, usually short and fine, recumbent, never obscuring the blackish dorsal body surface; pronotal and elytral sides narrowly flattened, typically the same color as disc, or slightly paler. Lateral margin of pronutum and elytra with a series of faintly distinct, small and short setae, each seta usually 0.3–0.5× as long as those on elytral disc; posterior margin of pronotum with long, usually distally trifid or multifid microsetae, microsetae uniformly distributed on middle region anterior to scutellum ( Fig. 14d ).

Dorsal habitus: body moderately convex, variably shaped, broadly oval to elongate and slender ( Fig. 14a ); dorsal punctures on discal portion of pronotum as large as or larger than eye facet, usually deeply impressed and densely distributed; anterior margin of clypeus usually moderately arcuately emarginate to subtruncate, distinctly narrowly bordered ( Fig. 14b ), without small, faintly, medial bulge; narrow circum-ocular furrows (occipital sulci) present on dorsal side of head, moderately to deeply impressed, complete ( Fig. 14b ); eyes large and usually moderately projecting laterally ( Figs. 14a, b ); pronotum with obtuse to obtusely rounded posterior angles, never directed posteriorly ( Fig. 14a ); scutellum regularly punctured on most of exposed portion ( Fig. 14d ); elytra with variable punctation, punctures simple, never transversely strigose; elytral humeral angle moderately distinct, not protruding laterally ( Fig. 14a ); elytral humeral striae scarcely distinct; elytral pre-sutural striae more or less distinct, originating at scutellar vertex, terminating close to elytral apex, and delimiting on each elytron a more or less distinctly raised and narrow sutural border, usually distinctly narrower than proximal portion of 3 rd antennomere; elytral apices truncately rounded in both sexes ( Fig. 14a ); pygidium partially exposed, moderately convex, apically rounded in both sexes ( Fig. 14a ).

Ventral habitus: antennal furrows markedly delimited, parallel-sided; mentum subpentagonal, normal shaped submental impression ( Fig. 14c ); antennal furrows of anterior margin of prosternum moderately raised and short ( Fig. 14c ); prosternal process relatively wide, subapical dilated portion nearly 2.3–2.5× as wide as maximum width of 1 st antennomere, usually bluntly convex distally ( Fig. 14e ); lateral borders of prosternal process delimiting moderately to shallowly impressed distinct furrows, distally terminating over predistal widely developed lateral expansions, near posterior margin ( Fig. 14e ), posterior margin not denticulate; posterior margin of mesoventrite simple, never medially incised ( Fig. 14e ); variably developed impressions on male metaventrite; first two visible abdominal ventrites simple in both sexes, without tufts of setae; caudal marginal lines of metacoxal cavities variable, subparallel and partially contiguous to posterior margin of metacoxal cavities, or strongly deviating posteriorly (Fig. 125 k in AUDISIO 1993b), comprising moderately deep arched impression of outer ‘axillary’ line ( Fig. 14g ); ‘axillary’ space on first abdominal ventrite reduced, ‘axillary’ angle bluntly right angled ( Fig. 14g ); large, long, and deeply impressed arched impressions on basal portion of last visible abdominal ventrite, usually partially covered by distal portion of penultimate visible abdominal ventrite ( Fig. 14f ); last visible abdominal ventrite in males frequently with tubercles or raised median posterior ridges.

Appendages: male 1 st antennomere 0.7–0.8× as long as width of protibiae excluding distal teeth ( Fig. 14a ); 3 rd antennomere in both sexes moderately long and slender, usually 2.0–2.1× as long as wide, and nearly 0.8–0.9× as long and distinctly thinner than 2 nd antennomere ( Figs. 14a, c ); 4 th and 5 th antennomeres subequal in both sexes, short, slightly longer than wide; antennal club compact, mid-sized, simple, comprising last 3 antennomeres in both sexes (8 th antennomere scarcely widened, nearly 0.5× as wide as 9 th antennomere) ( Fig. 14c ), narrower than width of protibiae, sexual dimorphism absent; labial palpi short in both sexes ( Fig. 14c ), terminal segment nearly1.6–1.7× as long as wide; maxillary palpi moderately long in both sexes ( Fig. 14c ), terminal segment 2.1–2.3× as long as wide; mandible mid-sized ( Fig. 14a ), apex acuminate, no sexual dimorphism; tarsal claws simple, never toothed at base; tarsi of normal size and shape, 0.5–0.7× as long as corresponding tibiae ( Fig. 14a ); protibiae with a series of variably shaped, usually moderately large, and frequently uneven (blunt to sharply acuminate) teeth on lateral margin ( Fig. 14a ; Figs. 127 g –m in AUDISIO 1993b), without subdistal group of longer teeth perpendicular to the margin of each tibia; meso- and metatibiae with lateral margin usually without sinuosity at distal third, bearing a single and moderately even row of relatively small robust spurs; only F. opacus possesses an uneven double series of spurs ( Fig. 14a ) and on metatbiae a distinct predistal sinuosity (the latter trait shared also by F. ciliatus ); meso- and metatibiae of variable width, usually slender and narrow ( Figs. 14a, h ), never subtrapezoidal or axe-shaped; usually with scarcely evident sexual dimorphism in metatibial shape; tarsal plates of prolegs distinctly wider in males; anterior margin of profemora and posterior margin of metafemora in both sexes without gibbosities, tubercles, or spines.

Male genitalia: processes along inner side of parameres absent (Fig. 138 in AUDISIO 1993b), tegmen with shallowly incised or subtruncate distal margin, without deep median longitudinal desclerotization from proximal portion of tegmen extending to medial distal V-shaped excision; median lobe of aedeagus variable, without lateral emargination, narrow, bluntly acuminate and variably shaped distally, usually with minute distal excision.

Female genitalia (ovipositor): variably shaped, usually large; styli usually short, simple, cylindrical, frequently more darkly pigmented, inserted close to apex of contiguous gonostyloids; each gonostyloid lightly sclerotized and frequently more darkly pigmented distally, with a simple, never indentate outer portion of basicoxites (Figs. 156 g –m in AUDISIO 1993b), and a single, narrow, lightly pigmented and sclerotized arcuate area along outer subdistal portion of gonostyloids. ‘Central point’ of ovipositor usually nearly centrally located, with proximad directed short spicule.

Etymology. The generic name is derived from the host-plant family of all inclusive species, i.e. Fabaceae , and from ‘- gethes ’, to emphasize both an association with this botanical family and a phylogenetic relationship with Meligethes . Gender masculine.

Biology. All species are strictly associated for larval development with flowers of Fabaceae , in particular Trifolium L., Onobrychis Miller , Ononis L., Lotus L., and allied genera ( AUDISIO 1993b).

Phylogenetic position. Available molecular and morphological datasets provide weak evidence for a monophyletic clade including Fabogethes gen. nov. as sister to Genistogethes gen. nov., with both clades being probably marginally related to Afrogethes gen. nov. and allied genera. However, phylogenetic relationships between these taxa remain unclear.

Taxonomy and geographic distribution. Fabogethes gen. nov. includes nine described Palaearctic species (one subsequently introduced to North America) (KIREJTSHUK 1992B; AUDISIO 1993b; AUDISIO et al. 2003a) formerly attributed to the ‘ Meligethes nigrescens ’ and ‘ M. opacus ’ species-groups.

Fabogethes brachialis ( Erichson, 1845) comb. nov. Europe, Caucasus, W Siberia

Fabogethes capucinus (Robert, 1909) comb. nov. N Algeria

Fabogethes ciliatus ( Easton, 1956) comb. nov. N Algeria, N Tunisia

Fabogethes circularis (J. Sahlberg, 1903) comb. nov. E Siberia, N Korea, China, Mongolia

Fabogethes diversus (Schilsky, 1893) comb. nov. E Turkey, Caucasus, W Middle Asia

Fabogethes himalayaensis (Kirejtshuk, 1980) comb. nov. N India, Nepal

Fabogethes nigrescens ( Stephens, 1830) comb. nov. Palaearctic Region, introduced to N America Fabogethes opacus ( Rosenhauer, 1856) comb. nov. W Mediterranean, S Ukraine: Crimea

Fabogethes varicollis ( Wollaston, 1854) comb. nov. Canary Islands, Madeira, W Mediterranean

Figures

Fig. 14. Fabogethes Audisio & Cline, gen. nov.: a – F. opacus (Rosenhauer, 1856); b–h – F. nigrescens (Stephens, 1830). a – male habitus (length 2.7 mm); b – dorso-lateral view of head; c – ventral view of head and anterior portion of prosternum; d – anterior portion of scutellum and microsetae on middle of posterior margin of pronotum; e – prosternal process and mesoventrite; f – exposed portion of last visible abdominal ventrite; g – caudal marginal line of metacoxal cavity; h – middle leg with outer margin of mesotibia. Scale bars: Figs. b, c, e, g = 100 μm.