Boragogethes 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 : 372-375

9. Boragogethes Audisio & Cline , gen. nov.

( Figs. 9 a–m )

Type species. Nitidula symphyti Heer, 1841: 405 (by present designation) [= Boragogethes symphyti ( Heer, 1841) comb. nov.].

Generic description and diagnosis. Inclusive species vary greatly in size (2.0– 3.2 mm length), and share the following combination of characters.

Body color and pubescence: pubescence usually moderately long and fine, recumbent, golden to silvery-whitish, never obscuring the variably colored dorsal body surface (brown, blackish, reddish, or blackish with orange spots on elytra); pronotal and elytral sides narrowly flattened, typically the same color as disc. Lateral margin of pronotum 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 short, usually distally bifid or trifid microsetae, microsetae uniformly distributed on middle region anterior to scutellum ( Fig. 9e ).

Dorsal habitus: body markedly convex, short or slender, more or less oval ( Figs. 9a, b ); dorsal punctures on discal portion of pronotum as large as or larger than eye facets, usually moderately deeply impressed and densely distributed; anterior margin of clypeus truncate, simple, without small distinct bulge medially, and distinctly bordered ( Figs. 9c, d ); circumocular furrows (occipital sulci) on dorsal side of head complete and distinct ( Figs. 9 c, d ); eyes large and usually moderately projecting laterally ( Figs. 9a–d ); pronotum with faintly distinct posterior angles, rounded to bluntly obtuse, never directed posteriorly ( Figs. 9a, b ); scutellum regularly punctured in most of exposed portion; elytra with simple punctation, never transversely strigose; elytral humeral angles faintly narrowly rounded, not protruding laterally ( Figs. 9a,b ); elytral humeral striae faint; elytral pre-sutural striae visible, originating at scutellar vertex or slightly posteriorly, terminating at elytral apex, and delimiting on each elytron a faintly distinct and raised sutural border, widest at posterior third, narrower than proximal width of 3 rd antennomere; elytral apices truncately rounded in both sexes ( Fig. 9a, b ); pygidium partially exposed, moderately convex, apically rounded in both sexes ( Figs. 9a, b ).

Ventral habitus: antennal furrows markedly delimited, nearly parallel-sided, or slightly divergent posteriorly; mentum subpentagonal ( Fig. 9f ); prosternal antennal furrows of anterior margin of prosternum moderately raised and short ( Fig. 9f ); prosternal process variably shaped, usually relatively narrow, subapical dilated portion 2.0–2.1× as wide as maximum width of 1 st antennomere, apex usually bluntly acuminate ( Fig. 9g ); lateral borders of prosternal process delimiting shallowly impressed but distinct furrows, distally terminating over predistal lateral expansions ( Fig. 9g ); posterior margin of mesoventrite simple, never incised medially ( Fig. 9g ); male impressions on metaventrite moderately developed; first two visible abdominal ventrites simple in both sexes, without tufts of setae; caudal marginal lines of metacoxal cavities always simple, parallel and contiguous to posterior margin of metacoxal cavities, without deep arched impression of outer ‘axillary’ line ( Fig. 9k ); ‘axillary’ space on first abdominal ventrite reduced, ‘axillary’ angle bluntly right angled or slightly obtuse ( Fig. 9k ); large and deeply impressed arched impressions on basal portion of last visible abdominal ventrite, usually not covered by distal portion of penultimate visible abdominal ventrite ( Fig. 9h ).

Appendages: male 1 st antennomere 0.8–1.0× as long as width of protibiae excluding distal teeth ( Figs. 9a, b ); 3 rd antennomere in both sexes 1.9–2.1× as long as wide, only 0.8–0.9× as long as but distinctly thinner than 2 nd antennomere ( Figs. 9a, b ); 4 th and 5 th antennomeres in both sexes subequal, short, slightly longer than wide; antennal club compact, small, simple, comprising last 3 antennomeres in both sexes ( Figs. 9a, b, f ), much narrower than width of protibiae, sexual dimorphism absent; labial palpi moderately long in both sexes ( Fig. 9f ), terminal segment 1.7–1.9× as long as wide; maxillary palpi moderately long and slender in both sexes ( Fig. 9f ), terminal segment 2.1–2.2× as long as wide; mandible mid-sized ( Fig. 9f ), apex faintly acuminate and simple, no sexual dimorphism present; tarsal claws simple, never toothed at base ( Fig. 9m ); tarsi of normal size and shape, 0.6–0.7× as long as corresponding tibiae ( Figs. 9a, b, m ); protibiae with a series of usually large, sharp, frequently uneven teeth on lateral margin ( Figs. 9a, b ; Figs. 129 b–c, p in AUDISIO 1993b); meso- and metatibiae on lateral margin bearing a moderately even row of fine pegs ( Fig. 9m ), with or without sinuosity at distal third; meso- and metatibiae of variable width, usually moderately flat, but slender ( Figs. 9a, b, m ), never distinctly subtrapezoidal or axe-shaped; no sexual dimorphism in tibial shape; tarsal plates of prolegs sligthly wider in males; posterior margin of metafemora simple in both sexes, without tubercles or projections.

Male genitalia: processes along inner side of parameres absent (Figs. 141 a–h in AUDISIO 1993b), tegmen with arcuately shaped or deep median incision on distal margin, without deep median longitudinal desclerotization from proximal portion of tegmen extending to medial distal V-shaped excision; median lobe of aedeagus variably shaped, without emargination laterally, rounded, distally subtruncate to acuminate, without distal minute excision or emargination.

Female genitalia (ovipositor): small and faintly sclerotized; styli moderately long, simple, cylindrical, unpigmented, inserted at apex of contiguous gonostyloids (Figs. 158 f–i in AUDISIO 1993b); each gonostyloid lightly sclerotized and never pigmented distally, with a simple, never indentate outer portion of basicoxites, and a single, narrow, unpigmented and sclerotized arcuate area along outer subdistal portion of gonostyloids; ‘central point’ of ovipositor nearly centrally located, without proximad directed spicule.

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

Biology. Members of Boragogethes gen. nov. are all associated at larval stages with flowers of Boraginaceae , which likely colonized in a single ecological shift on members of Symphytum L. for the B. symphyti species-group, or on Anchusa L. for members of the B. rosenhaueri species-group ( AUDISIO 1993b).

Phylogenetic position. Available molecular and morphological data provide only weak evidence for a possible monophyletic clade including Boragogethes gen. nov. in a relatively basal position, and related to Idiogethes , and likely to members of the Lariopsis generic complex. However, phylogenetic relationships between these taxa remain unclear.

Taxonomy and geographic distribution. Boragogethes gen. nov. includes five Palaearctic species, attributed to two formerly recognized species-groups, i.e. the ‘ Meligethes symphyti ’, and ‘ M. rosenhaueri ’ species-groups ( AUDISIO 1993b).

Boragogethes intermedius (Kirejtshuk, 1979) comb. nov. Kazakhstan

Boragogethes mandibularis (J. Sahlberg, 1913) comb. nov. Turkey, Caucasus

Boragogethes punctatissimus (Reitter, 1896) comb. nov. Turkey, Armenia

Boragogethes rosenhaueri ( Reitter, 1871) comb. nov. E Europe, Near East, W Middle Asia

Boragogethes symphyti ( Heer, 1841) comb. nov. Europe, Near East, N Africa: N Algeria

Figures

Fig. 9. Boragogethes Audisio & Cline, gen. nov.: a, d, k, m – B. symphyti (Heer, 1841); b–c, e–h – B. rosenhaueri (Reitter, 1871). a, b – male habitus (a – length 3.0 mm; b – length 2.5 mm); c, d – dorsal view of head; e – microsetae on posterior margin of pronotum; f – ventral view of head and anterior portion of prosternum; g – prosternal process and mesoventrite; h – exposed portion of last visible abdominal ventrite; k – caudal marginal lines of metacoxal cavities; m – outer margin of mesotibia. Scale bars: Figs. c, d, f, g, h, m = 100 μm; Fig. e = 20 μm; Fig. k = 200 μm.