Idiogethes Kirejtshuk, 1977

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 : 370-372

8. Idiogethes Kirejtshuk, 1977 stat. restit.

( Figs. 8 a–e )

Idiogethes Kirejtshuk, 1977: 626 [originally described as a separate genus, but later considered a subgenus of

Meligethes Stephens, 1830 ( KIREJTSHUK 1980b), or a synonym of the subgenus Clypeogethes Scholz, 1932 in the genus Meligethes Stephens, 1830 ( KIREJTSHUK 2008)].

Type species. Idiogethes angustitarsis Kirejtshuk, 1977: 626 (by original designation).

Generic redescription and diagnosis. Inclusive species vary moderately in size (1.9–2.4 mm length), and share the following combination of characters.

Body color and pubescence: pubescence golden to silvery-whitish or brownish, relatively long and fine, recumbent, never obscuring the variably colored dorsal body surface (reddish, brown, or brown with yellowish elytra); pronotal sides narrowly flattened, elytral sides exceptionally narrowly margined and typically the same color as disc. Lateral margin of pronotum and elytra with a series of distinct, and relatively long setae, each seta usually 0.7–0.9× as long as those on elytral disc; posterior margin of pronotum with moderately long, distally bifid or trifid microsetae, microsetae uniformly distributed on middle region anterior to scutellum.

Dorsal habitus: body subcylindrical, transversally convex, peculiarly narrow and parallelsided ( Fig. 8a ); dorsal punctures on discal portion of pronotum as large as or larger than eye facets, shallowly impressed and densely distributed; anterior margin of clypeus with deep and widely V-shaped emargination, without small distinct bulge medially, and distinctly bordered ( Figs. 8a, b ); circum-ocular furrows (occipital sulci) on dorsal side of head absent; eyes small and faintly projecting laterally ( Fig. 8a ); pronotum with obtusely rounded posterior angles, never directed posteriorly ( Fig. 8a ); scutellum regularly punctured in most of exposed portion; elytra with simple punctation, never transversely strigose, with faint traces of orange peel-like rugosity; elytral humeral angle faintly distinct ( Fig. 8a ); elytral humeral striae usually indistinct; elytral pre-sutural striae visible, originating at scutellar vertex, terminating at elytral apex, and delimiting on each elytron a distinct, fine, narrow, slightly raised and even sutural border, much narrower than proximal width of 3 rd antennomere; elytral apices truncately rounded in both sexes ( Fig. 8a ); pygidium partially exposed, convex, rounded to shortly flatly lobed apically in males ( Fig. 8a ), more distinctly flatly lobed in females ( Fig. 9 in KIREJTSHUK 1977a).

Ventral habitus: antennal furrows distinctly delimited, peculiarly short, nearly parallelsided; mentum subpentagonal; prosternal antennal furrows of anterior margin of prosternum completely absent (as in Fig. 1b ); prosternal process narrow ( Fig. 7 in KIREJTSHUK 1977a), comprising moderately dilated subapical portion, 1.9–2.0× as wide as maximum width of 1 st antennomere, apex blunt; lateral borders of prosternal process delimiting shallowly impressed but distinct furrows, distally terminating prior to predistal lateral expansions; posterior margin of mesoventrite simple, not incised medially; faintly developed male impressions on metaventrite; first two visible abdominal ventrites simple in both sexes, without tufts of setae; caudal marginal lines of metacoxal cavities simple, parallel and contiguous to posterior margin of metacoxal cavities, with moderately deep arched impression of outer ‘axillary’ line; ‘axillary’ space on first abdominal ventrite moderately developed, ‘axillary’ angle broadly obtuse; shallowly impressed arched impressions on basal portion of last visible abdominal ventrite wide but short, usually largely covered by distal portion of penultimate visible abdominal ventrite (as in Fig. 6k , but shorter; Fig. 9 in KIREJTSHUK 1977a).

Appendages: male 1 st antennomere 0.9–1.0× as long as width of protibiae excluding distal teeth ( Figs. 8a, c ); 3 rd antennomere in both sexes moderately short, usually only 1.8–1.9× as long as wide, nearly 1.0× as long as but distinctly thinner than 2 nd antennomere ( Figs. 8a, c ); 4 th antennomere in both sexes subequal, short, faintly as long as wide, 5 th to 8 th antennomeres peculiarly short, distinctly wider than long; antennal club compact, peculiarly small, simple, comprising last 3 antennomeres in both sexes (8 th antennomere scarcely widened, nearly 0.5× as wide as 9 th antennomere) ( Figs. 8a, c ), distinctly narrower than protibial width, sexual dimorphism absent; labial palpi relatively short in both sexes (as in Fig. 7c ), terminal segment 1.8–1.9× as long as wide; maxillary palpi moderately long and slender in both sexes, terminal segment 2.1–2.2× as long as wide; mandible small, apex acuminate, no sexual dimorphism present; tarsal claws simple, never toothed at base (as in Fig. 5e ); tarsi peculiarly long and thin, middle and posterior tarsi 0.8–1.0× as long as corresponding tibiae ( Figs. 8a, d ); protibiae long and narrow, with a series of usually large, serrate, uneven, moderately acuminate teeth on lateral margin ( Figs. 8a, d ); meso- and metatibiae on lateral margin bearing long setae and a nearly simple and usually uneven row of relatively large pegs, without U-shaped sinuosity at distal third ( Figs. 8a, e ); meso- and metatibiae narrow, parallel-sided, usually flat and slender ( Figs. 8a, e ), never distinctly subtrapezoidal or axe-shaped; tarsal plates of prolegs narrow in both sexes, faintly wider in males; no sexual dimorphism in meso- and metafemoral shape, posterior margins simple, without projections or tubercles.

Male genitalia: processes along inner side of parameres absent ( JELÍNEK 1982b), with deep excision along distal margin, and without deep median longitudinal desclerotization from proximal portion of tegmen extending to medial distal V-shaped excision; median lobe of aedeagus without emargination laterally, obtusely acuminate or spatulate distally.

Female genitalia (ovipositor): small; styli usually short, simple, cylindrical, not pigmented, inserted at apex of apically narrowly separated gonostyloids, each gonostyloid faintly sclerotized and not darkly pigmented distally, with a simple, never indentate outer portion of basicoxites ( Fig. 10 in KIREJTSHUK 1977b; JELÍNEK 1982b), and a single, variably shaped, unpigmented arcuate area along outer subdistal portion of gonostyloids. ‘Central point’ of ovipositor located more proximad than middle, without proximally directed spicule.

Etymology. The generic name is derived from a combination of the Greek ‘ιδιος’ (= peculiar, particular) to emphasize the peculiarly narrow body and tarsi, and from ‘- gethes ’, to emphasize its phylogenetic relationship with Meligethes . Gender masculine.

Biology. Species of Idiogethes are strictly associated for larval development with flowers of Boraginaceae , in particular with suberemic species of Heliotropium L.

Phylogenetic position. Available morphological datasets from imaginal stages provide weak evidence of a possibly natural clade including Idiogethes and Boragogethes gen. nov. (developing on Boraginaceae ), with Idiogethes also likely being related to the Lariopsis generic complex (developing on Asteraceae and Mesembryanthemaceae ) as well as Acanthogethes (developing on Cistaceae ).

Taxonomy and geographic distribution. Idiogethes includes two described species distributed in Middle Asia ( KIREJTSHUK 1977a; JELÍNEK 1982b; JELÍNEK & AUDISIO 2007).

Idiogethes angustitarsus Kirejtshuk, 1977 comb. restit. Turkmenistan, Uzbekistan

Idiogethes bactrianus (Jelínek, 1982) comb. nov. Tajikistan, Turkmenistan

Figures

Fig. 8. Idiogethes Kirejtshuk, 1977: a–e – I. angustitarsus Kirejtshuk, 1977. a – male habitus (length 2.2 mm); b – dorsal view of head; c – antenna; d – anterior leg; e – mesotibia. Figs. b–e: refer to KIREJTSHUK (1977a) for scale.

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.

Fig. 1. Acanthogethes Reitter, 1871: a–h – A. fuscus (Olivier, 1790). a – male habitus (length 3.5 mm); b – ventral view of head and anterior portion of prosternum; c – dorsal view of head; d – scutellum and microsetae on posterior margin of pronotum; e – prosternal process and mesoventrite; f – exposed portion of last visible abdominal ventrite; g – caudal marginal lines of metacoxal cavities; h – middle leg illustrating outer margin of mesotibia. Scale bars: Figs. b, c = 200 μm; Figs. d, e, f, g, h = 100 μm.

Fig. 7. Xerogethes Audisio & Cline, gen. nov.: a – X. osellai (Audisio & Jelínek, 2000); b–g – X. rotundicollis (C. N. F. Brisout de Barneville, 1863). a – male habitus (length 2.0 mm); b – dorso-lateral view of head; c – ventral view of head and anterior portion of prosternum; d – prosternal process and mesoventrite; e – exposed portion of last visible abdominal ventrite; f – caudal marginal lines of metacoxal cavities; g – microsetae on middle of posterior margin of pronotum. Scale bars: Figs. b, c, d, e, f = 100 μm; g = 30 μm.

Fig. 6. Clypeogethes Scholz, 1932 and Xerogethes Audisio & Cline, gen. nov.: a, c – C. chlorocyaneus (Jelínek & Audisio, 1977); b, d–e – C. elongatus (Rosenhauer, 1856); k–n – C. lepidii (Miller, 1851); f–g – X. osellai (Audisio & Jelínek, 2000); h – X. rotundicollis (C. N. F. Brisout de Barneville, 1863). a – male habitus (length 2.5 mm); b, c, h – ovipositors; d–e, f–g – male genitalia; k – exposed portion of last visible abdominal ventrite; m – dorsal view of head; n – ventral view of head and anterior portion of prosternum. Figs. b–h: refer to AUDISIO (1993b) and AUDISIO et al. (2000) for scale. Scale bars: Figs. k, m, n = 100 μm.

Fig. 5. Neolariopsis Audisio & Cline, gen. nov.: a, c–h – N. cercoides (Reitter, 1872); b – N. thalycroides (Kirejtshuk & Audisio, 1995). a, b – male habitus (a – length 2.1 mm, b – length 2.1 mm); c – dorsal view of head; d – ventral view of head and anterior portion of prosternum; e – middle leg with outer margin of mesotibia; f – prosternal process and mesoventrite; g – exposed portion of last visible abdominal ventrite; h – antenna. Scale bars: Figs. c, d, f = 100 μm; Figs. e, h = 20 μm; Fig. g = 30 μm.

Fig. 10. Afrogethes Audisio & Cline, gen. nov.: a – A. tristis (Sturm, 1845); b–d, h – A. reticulatus (Reitter, 1872); e – A. alani (Kirejtshuk, 1988); f–g – A. planiusculus (Heer, 1841); k – A. isoplexidis (Wollaston, 1854). a, k – male habitus (a – length 2.6 mm; k – length 2.5 mm); b – dorsal view of head; c – prosternal process; d – ventral view of head and anterior portion of prosternum; e – microsetae on middle posterior margin of pronotum; f – exposed portion of last visible abdominal ventrite; g – caudal marginal lines of metacoxal cavities; h – outer margin of mesotibia. Scale bars: Figs. b, c, d, f, g, h = 100 μm; Fig. e = 20 μm.