Tarchonanthogethes 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 : 439-442

27. Tarchonanthogethes Audisio & Cline , gen. nov.

( Figs. 27 a–k )

Type species. Pria martini Grouvelle, 1899: 147 , 148 (partim), nec Anthystrix martini sensu KIREJTSHUK & EASTON (1988) : 42, 46 (partim) (by present designation) [= Tarchonanthogethes martini (Grouvelle, 1899) comb. nov.]. See AUDISIO et al. (2009a).

Generic description and diagnosis. Inclusive species vary greatly in size (1.6–2.7 mm length), and share the following combination of characters.

Body color and pubescence: pubescence variable, usually long, golden to silvery-whitish and dense, recumbent, partially obscuring the predominantly orange-brown dorsal body surface; pronotal and elytral sides flattened and usually paler than disc ( Fig. 27a ); a few isolated species possess much finer and shorter pubescence, not obscuring the dorsal body surface ( Fig. 27b ); lateral margin of pronotum and elytra with a series of faintly distinct, small and short setae, each seta 0.3–0.5× as long as those on elytral disc; posterior margin of pronotum with relatively short, distally multifid microsetae, microsetae also on middle portion anterior to scutellum ( Fig. 27f ).

Dorsal habitus: body moderately convex, oval ( Figs. 27a, b ); dorsal punctures on discal portion of pronotum as large as or larger than eye facet, moderately to deeply impressed ( Figs. 27a, b ); anterior margin of clypeus truncate to slightly emarginate medially, simple, without small distinct medial bulge, and more or less distinctly bordered ( Figs. 27a, b, i ); circum-ocular furrows (occipital sulci) on head deeply impressed and complete ( Fig. 27i ); eyes large and usually markedly projecting laterally ( Figs. 27a, b ); posterior angles of pronotum distinct, blunt, obtuse ( Figs. 27a, b ), never directed posteriorly; scutellum uniformly punctured on most of exposed portion ( Fig. 27f ); elytra with strongly variable punctation, normal and not transversely strigose, or confusedly orange peel-like sculpturing, or finely and completely transversely strigose sculpturing; elytral humeral angle distinct, broadly obtuse, never laterally protruding ( Figs. 27a, b ); elytral humeral striae not distinct; elytral pre-sutural striae faintly visible, originating at scutellar vertex or slightly posterior, terminating at elytral apex, and delimiting on each elytron a faintly distinct, flat, unraised sutural border, more distinct at distal fourth, distinctly narrower than proximal width of 3 rd antennomere; elytral apices truncately rounded in both sexes ( Fig. 27a ), only the isolated T. rotundiclava possesses elytra faintly obtusely lobed posteriorly in females; pygidium partially exposed, moderately convex, apically rounded in both sexes ( Figs. 27a, b ).

Ventral habitus: antennal furrows markedly delimited, and moderately convergent posteriorly or nearly subparallel; mentum subpentagonal ( Fig. 27g ); prosternal antennal furrows on anterior margin of prosternum strongly delimited and raised, moderately divergent, never extending posteriorly to anterior margin of procoxal cavity ( Fig. 27g ); prosternal process variably shaped, moderately to markedly wide, subapical portion 2.0–2.7× as wide as maximum width of 1 st antennomere, apex usually bluntly rounded ( Fig. 27g ); lateral borders of prosternal process delimiting deeply impressed and distinct furrows, distally terminating over predistal lateral expansions ( Fig. 27g ); posterior margin of mesoventrite simple, never medially incised; scarce sexual dimorphism expressed in male impressions on metaventrite; first two visible abdominal ventrites simple in both sexes, without tufts of setae; caudal marginal lines of metacoxal cavities simple, subparallel 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 more or less obtuse; strongly marked 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. 27g ).

Appendages: male 1 st antennomere 0.8–1.1× as long as width of protibiae excluding distal teeth ( Figs. 27g, h ); 3 rd antennomere 2.0–3.0× as long as wide in both sexes, distinctly longer and much thinner than 2 nd; 4 th and 5 th antennomeres usually subequal in both sexes, relatively short, moderately longer than wide ( Fig. 27h ); male and female antennal club moderately compact, nearly symmetric, comprising last 3 antennomeres, only the isolated T. rotundiclava with 4-jointed male antennal club ( Figs. 27a, h ); labial palpi relatively short in both sexes (as in Fig. 26b ), terminal segment 1.6–1.7× as long as wide; maxillary palpi relatively long and slender in both sexes (as in Fig. 26c ), terminal segment 1.8–1.9× as long as wide; mandible mid-sized, moderately short, apex bifid and moderately acuminate, no sexual dimorphsim; tarsi of normal size and shape, 0.7–0.9× as long as corresponding tibiae ( Figs. 27a, b, g ); tarsal claws simple, never toothed at base; protibiae with highly variable teeth on outer margins, simple, small and crenulate ( Fig. 27a ) to strongly developed and serrate; lateral margin of meso- and metatibiae bearing a single and regular row of long and thin, yellowish pegs ( Figs. 27a, b, g ), without U-shaped sinuosity at distal third; meso- and metatibiae triangular, of variable width, long and slender to subtrapezoidal; usually scarce sexual dimorphism in tibial shape; tarsal plates of prolegs wider in males; posterior margin of metafemora simple in both sexes, without tubercles or projections.

Male genitalia: tegmen variably shaped, usually without processes along inner side of parameres ( Fig. 27c ; Plate 2, Figs. 7–8 , 10–11 , 13–14 , 16– 17 in KIREJTSHUK & EASTON 1988), and without deep median longitudinal desclerotization from proximal portion of tegmen extending to medial distal V-shaped excision; median lobe of aedeagus variably shaped, without lateral emargination, apex variable ( Fig. 27d ); main sclerites of internal sac (flagellum) usually large, markedly sclerotized, ~2× shorter than aedeagus ( Fig. 27e ).

Female genitalia (ovipositor): variably shaped, usually large; styli usually long and distinct, simple, unpigmented, inserted near narrow but frequently minutely subtruncate apex of contiguous or distally narrowly divergent (known from a single case, i.e. Plate 2, Fig. 15 in KIREJTSHUK & EASTON 1988) gonostyloids, each gonostyloid usually lightly sclerotized and moderately pigmented distally, with a simple, never indentate outer portion of basicoxites ( Fig. 27k ), and a single or frequently double, pigmented and sclerotized arcuate area(s) along outer subdistal portion of gonostyloids. ‘Central point’ of ovipositor usually located more distad than middle, without proximad directed spicule.

Etymology. The generic name is derived from the host-plant tribe of all inclusive species, i.e. Tarchonantheae , and from ‘- gethes ’, to emphasize its phylogenetic relationship with Meligethes . Gender masculine.

Biology. All species are strictly associated for larval development with male inflorescences of trees and bushes of Asteraceae , within the phylogenetically isolated tribe Tarchonantheae (specifically with the genera Brachylaena R. Br. and Tarchonanthus L.) (AUDISIO et al. unpublished data).

Phylogenetic position. This genus is relatively large and heterogeneous when compared to other genera within the Anthystrix generic complex, and appears to be more closely related to Anthystrix based on some features and to Cyclogethes based on other characters. Some of the described species have been previously erroneously attributed to the more distantly related genera Meligethinus and Meligethes (see below).

Taxonomy and geographic distribution. Tarchonanthogethes gen. nov. includes 6 described species and more than 10 species awaiting formal description. The genus exhibits an expression of a transformation series involving several morphological characters, and may be separated at least into five distinct groups, i.e. the ‘ martini ’, ‘ rotundiclava’, ‘ capeneri ’, ‘ flavus ’, and ‘ singularis ’ species-groups. An upcoming paper is devoted to a complete taxonomic revision of the genus (AUDISIO et al. in prep.).

Tarchonanthogethes capeneri ( Kirejtshuk & Easton, 1988) South Africa: Limpopo, NW Province comb. nov. (from Meligethinus )

Tarchonanthogethes flavus ( Kirejtshuk & Easton, 1988) South Africa: Limpopo, NW Province comb. nov. (from Meligethinus )

Tarchonanthogethes hirtus ( Kirejtshuk & Easton, 1988) South Africa: KwaZulu-Natal, Mpumalanga comb. nov. (from Meligethinus )

Tarchonanthogethes martini (Grouvelle, 1899) South Africa: KwaZulu-Natal, Mpumalanga comb. nov.

= Pria martini Grouvelle, 1899 , nec Anthystrix martini sensu KIREJTSHUK & EASTON (1988)

Tarchonanthogethes rotundiclava (Kirejtshuk & South Africa: Eastern Cape, KwaZulu-Natal Easton, 1988) comb. nov. (from Anthystrix )

Tarchonanthogethes singularis ( Grouvelle, 1919) South Africa or Zimbabwe (localization of type locality comb. nov. (from Meligethes ) uncertain)

Figures

Fig. 27. Tarchonanthogethes Audisio & Cline, gen. nov.: a, c–i – T. rotundiclava (Kirejtshuk & Easton, 1988); b – T.sp.; k – T. martini (Grouvelle, 1899). a, b – male habitus (a – length 2.6 mm; b – length 2.0 mm); c–d – male genitalia (c – length 0. 43 mm; d – length 0.38 mm); e – major sclerites of male endophallus (length 0.20 mm); f – scutellum and microsetae on middle of posterior margin of pronotum; g – ventral view of body; h – male antenna (length 0.65 mm); i – dorsal view of head; k – distal portion of ovipositor (length 0.4 mm). Scale bars: Figs. f, i = 100 μm; Fig. g = 300 μm.

Fig. 26. Anthystrix Kirejtshuk, 1981: a, f–g, i – A.squamosa Kirejtshuk, 1981; b–e, h, k, m – A. longiclava Kirejtshuk & Easton, 1988. a – male habitus (length 2.5 mm); b – labium and right labial palpus; c – right maxilla and palpus; d – left mandible; e – labrum; f–g – male genitalia; h – ventral view of head and anterior portion of prosternum; i – distal portion of ovipositor; k – male antennal club; m – major sclerites of male endophallus. Drawings b–m: refer to AUDISIO et al. (2009a) for scale.

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. 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. 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.

Fig. 11. Indogethes Audisio & Cline, gen. nov.: a–m – I. curvipes (Grouvelle, 1908). a – male habitus (pubescence and mandibles not illustrated; length 3.5 mm); b – dorsal view of head; c – prosternal process and mesoventrite; d – microsetae on middle of posterior margin of pronotum; e – ventral view of head and anterior portion of prosternum; f – exposed portion of last visible abdominal ventrite; g – caudal marginal line of metacoxal cavity; h–k – male genitalia (h – length 0.5 mm; k – 0.4 mm); m – ovipositor (length 0.7 mm). Scale bars: Figs. b, c, e, f, g = 200 μm; Fig. d = 10 μm.

Fig. 13. Genistogethes Audisio & Cline, gen. nov.: a – G. immundus (Kraatz, 1858); b–h – G. punctatus (C. N. F. Brisout de Barneville, 1863). a – male habitus (length 2.7 mm); b – dorso-lateral view of head; c – ventral view of head and anterior portion of prosternum; d – caudal marginal line of metacoxal cavity; e – anterior portion of scutellum and microsetae on middle of posterior margin of pronotum; f – exposed portion of last visible abdominal ventrite; g – prosternal process and mesoventrite; h – middle leg with outer margin of mesotibia. Scale bars: Figs. b, c, d, f, g, h = 100 μm; Fig. e = 30 μm.

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.

Fig. 16. Sagittogethes Audisio & Cline, gen. nov.: a – S. ater (C. N. F. Brisout de Barneville, 1863); b – S. lindbergi (Rebmann, 1940); c, f–g – S. maurus (Sturm, 1845); d–e, h–k – S. obscurus (Erichson, 1845). a, b – male habitus (a – length 2.9 mm; b – length 2.5 mm); c – dorsal view of head; d – ventral view of head and anterior portion of prosternum; e – ventral view of body; f – last tarsomere of a middle leg; g – prosternal process and mesoventrite; h – anterior portion of scutellum and microsetae on middle posterior margin of pronotum; k – middle leg with outer margin of mesotibia. Scale bars: Figs. c, g, k = 100 μm; Figs. d, e = 200 μm; Fig. f = 20 μm; Fig. h = 30 μm.

Fig. 17. Aristogethes Audisio & Cline, gen. nov.: a – A. translatus (Grouvelle, 1913); b – A. pecten (Audisio, Kirk-Spriggs & Kirejtshuk, 1998); c, e–k – A. pubescens (Reitter, 1872); d, m – A. marshalli (Grouvelle, 1914). a, b – male habitus (a – length 2.6 mm; b – length 2.4 mm); c, d – dorsal view of head; e – ventral view of head and anterior portion of prosternum; f – prosternal process and mesoventrite; g – anterior portion of scutellum and microsetae on middle of posterior margin of pronotum; h – exposed portion of last visible abdominal ventrite; k – caudal marginal line of metacoxal cavity; m – last tarsomere of middle leg. Scale bars: Figs. d, f, h, k, m = 100 μm; Fig. g = 20 μm.

Fig. 15. Thymogethes Audisio & Cline, gen. nov.: a, h – T. egenus (Erichson, 1845); b – T. subfumatus (Ganglbauer, 1899); c–g, k – T. nigritus (Lucas, 1849). a, b – male habitus (a – length 2.5 mm; b – length 2.7 mm); 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 – dorsal view of head; f – prosternal process and mesoventrite; g – caudal marginal line of metacoxal cavity; h – exposed portion of last visible abdominal ventrite; k – middle leg with outer margin of mesotibia. Scale bars: Figs. c, e, f, g, h = 100 μm; Fig. d = 20 μm.