Chromogethes Kirejtshuk, 1989

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 : 428-432

24. Chromogethes Kirejtshuk, 1989 stat. nov.

( Figs. 24 a–h)

Chromogethes Kirejtshuk, 1989: 85 (described as a subgenus of Meligethes Stephens, 1830 ).

Type species. Meligethes splendidulus Reitter, 1873: 50 (by original designation) [= Chromogethes splendidulus (Reitter, 1873) comb. nov.].

Generic redescription and diagnosis. Inclusive species vary greatly in size (1.3–3.5 mm length), and share the following combination of characters.

Body color and pubescence: pubescence variable, usually short and fine, recumbent, long and prostrate in a few species ( Fig. 24a), golden to silvery-whitish and dense, rarely partially obscuring the predominantly metallic green dorsal body surface; pronotal and elytral sides narrowly to widely flattened, usually same color as disc, several species with pale, orange to reddish sides ( Fig. 24a); lateral margin of pronutum 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 long, usually distally bifid microsetae, absent medially anterior to scutellum ( Fig. 24c).

Dorsal habitus: body moderately convex, oval, usually long and narrow, rarely relatively short and wide ( Fig. 24a; Figs. 2 , 16, 17 in AUDISIO & DE BIASE 2004b); dorsal punctures on discal portion of pronotum as large as or larger than eye facet, usually moderately to deeply impressed ( Figs. 24a, k); anterior margin of clypeus truncate to markedly emarginate medially, simple, without small distinct medial bulge, and usually distinctly bordered ( Figs. 24b, k); circum-ocular furrows (occipital sulci) on dorsal side of head variable, deeply impressed and complete in most species ( Fig. 24k), scarcely evident and almost obliterated anteriorly in a few species ( Fig. 24b); eyes large and usually moderately projecting laterally ( Fig. 24a); posterior angles of pronotum distinct, blunt, usually obtuse ( Fig. 24a), never directed posteriorly, except in the Southern African C. venustus (Kirejtshuk, 1988) ; scutellum uniformly punctured on most of exposed portion ( Fig. 24c); elytral punctures simple, never transversely strigose, a few species with confused and reticulate longitudinal orange-peel like rugosity; elytral humeral angle faintly distinct, widely obtuse, never protruding laterally ( Fig. 24a); elytral humeral stria usually indistinct; elytral pre-sutural striae distinct, originating at scutellar vertex, terminating close to elytral apex, and delimiting on each elytron a moderately raised and narrow sutural border, markedly narrower than proximal portion of 3 rd antennomere; elytral apices truncately rounded in both sexes ( Fig. 24a); pygidium partially exposed, moderately convex, apically rounded in both sexes ( Fig. 24a).

Ventral habitus: antennal furrows markedly delimited, and moderately convergent posteriorly; mentum subpentagonal ( Fig. 24d); prosternal antennal furrows on anterior margin of prosternum faintly distinct in most species, more distinctly delimited in a few species, moderately divergent posteriorly, short, scarcely raised, never reaching anterior margin of procoxal cavity ( Fig. 24d); prosternal process variably shaped, usually narrow, subapical portion 1.6–2.2× as wide as maximum width of 1 st antennomere, apex usually bluntly rounded ( Fig. 24h); lateral borders of prosternal process delimiting shallowly impressed but distinct furrows, never distally terminating over predistal lateral expansions ( Fig. 24h); posterior margin of mesoventrite simple, never medially incised ( Fig. 24h); usually marked sexual dimorphism in impressions on metaventrite and/or tubercles; first two visible abdominal ventrites simple in both sexes, without tufts of setae, caudal marginal lines of metacoxal cavities always simple, subparallel and contiguous to posterior margin of metacoxal cavities, with shallowly arched impression of outer ‘axillary’ line; ‘axillary’ space on first abdominal ventrite highly reduced, ‘axillary’ angle nearly right angled; usually short and deeply impressed arched impressions on basal portion of last visible abdominal ventrite, frequently partially covered by distal portion of penultimate visible abdominal ventrite ( Fig. 24e).

Appendages: male 1 st antennomere 0.8–1.0× as long as width of protibiae excluding distal teeth ( Figs. 24a, b); 3 rd antennomere in both sexes usually 2× as long as wide, nearly as long as but much thinner than 2 nd; 4 th and 5 th antennomeres subequal in both sexes, moderately short, slightly longer than wide ( Fig. 24b); antennal club compact, peculiarly small, simple, comprising last 3 antennomeres in both sexes ( Fig. 24b), usually slightly narrower than width of protibiae, sexual dimorphism absent; labial palpi relatively long and slender in both sexes ( Fig. 24d), terminal segment 1.5–1.6× as long as wide; maxillary palpi moderately long and slender in both sexes ( Fig. 24d), terminal segment 2.0–2.3× as long as wide; mandible midsized, length variable and apex moderately acuminate, sexual dimorphism usually absent ( Fig. 24d); tarsal claws simple, never toothed at base ( Fig. 24f); tarsi of normal size and shape, 0.7–0.9× as long as corresponding tibiae ( Fig. 24a); protibiae usually with reduced teeth on outer margins ( Fig. 24a), a single much longer and isolated subapical narrow and spine-like tooth present in a few species; lateral margin on meso- and metatibiae bearing a single and regular row of long and thin, yellowish pegs ( Fig. 24g), without U-shaped sinuosity at distal third; meso- and metatibiae triangular, of variable width, usually long and slender ( Fig. 24a), rarely wider and shorter, never subtrapezoidal or axe-shaped; sexual dimorphism expressed in sinuate meso- and metatibiae (rarely protibiae); tarsal plates of prolegs more or less distinctly wider in males; posterior margin of meso- and metafemora usually simple in both sexes, without tubercles or projections, rarely with blunt teeth or gibbosities in males.

Male genitalia: variable, processes along inner side of parameres absent ( Figs. 3–10 in AUDISIO & DE BIASE 2004b), usually with moderately deep and narrow V-shaped excision along 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, rounded, subtruncate to acuminate distally, usually with distal minute excision or emargination; main sclerites of internal sac (flagellum) small, relatively arcuate, usually S-shaped in lateral view, and moderately sclerotized, typically 3–4× shorter than aedeagus.

Female genitalia (ovipositor): variably shaped, usually large; styli usually long and distinct, simple, frequently at least partially pigmented, inserted close to apex of contiguous gonostyloids, each gonostyloid lightly sclerotized and often markedly pigmented distally, with a simple, never indentate outer portion of basicoxites ( Figs. 11–15 in AUDISIO & DE BIASE 2004b), and a single, small, pigmented and more sclerotized arcuate area 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 obviously derived from Greek ‘χρωμα’ (= color), which is indicative of the usually bright metallic green color characterizing the body surface of almost all inclusive species, and from ‘- gethes ’, to emphasize its phylogenetic relationship with Meligethes . Gender masculine.

Biology. All species are apparently strictly associated for larval development with inflorescences of Asteraceae , in particular with the tribes Inuleae, Senecioneae , and Gnaphalieae , specifically on the following genera Helichrysum Mill. , Senecio L., and Metalasia R. Br. ( AUDISIO & DE BIASE 2004b, and unpublished data), and allied genera.

Phylogenetic position. Available molecular and morphological datasets provide strong evidence of the robustness of a relatively large monophyletic clade that includes the ‘ Anthystrix complex of genera’ ( Anthystrix , Sebastiangethes , Tarchonanthogethes gen. nov., Xenostrongylogethes gen. nov., and Cyclogethes ; AUDISIO et al. 2008, TRIZZINO et al. 2009) and Chromogethes . The shared larval host plant family ( Asteraceae ) of the entire clade [‘ Anthystrix complex of genera’ + ( Chromogethes )] also supports a common phylogenetic origin for this assemblage. With regards to Chromogethes , this genus exhibits a combined series of both autapomorphic and symplesiomorphic chararcters, which further suggests its placement in a relatively basal phylogenetic position in Meligethinae clade.

Taxonomy and geographic distribution. This taxon includes 31 described Afrotropical species, distributed from Somaliland to South Africa ( AUDISIO & KIREJTSHUK 1995, KIREJTSHUK 2001, AUDISIO & DE BIASE 2004b). Several other new species, still awaiting description, are also known from East, Central, and Southern Africa (AUDISIO unpublished data). Inclusive species are tentatively attributed to three formerly recognized species-groups, i.e. the ‘ Meligethes splendidulus ’, ‘ M. illustris ’, and ‘ M. sjoestedti ’ species-groups, besides a few more isolated southern African species.

Chromogethes amicus ( Kirejtshuk, 2001) comb. nov. Kenya

Chromogethes basilewskyi ( Audisio & Kirejtshuk, 1995) Tanzania comb. nov.

Chromogethes brincki (Kirejtshuk, 1995) comb. nov. South Africa: W Cape

Chromogethes cavifrons ( Kirejtshuk & Easton, 1988) South Africa: E Cape, Mpumalanga comb. nov.

Chromogethes clarkei ( Audisio & Kirejtshuk, 1995) Ethiopia comb. nov.

Chromogethes cultus ( Kirejtshuk, 2001) comb. nov. Kenya

Chromogethes favus ( Easton, 1960) comb. nov. Kenya

Chromogethes flaccus (Kirejtshuk, 1995) comb. nov. South Africa: W and E Cape

Chromogethes formosus ( Kirejtshuk, 1989) comb. nov. South Africa: KwaZulu-Natal, Mpumalanga 2)

= Meligethinus formosus Kirejtshuk, 1989

= Meligethes albens Audisio & De Biase, 2004 ,

syn. nov.

Chromogethes gemma ( Easton, 1960) comb. nov. Tanzania, Uganda

Chromogethes illustris (Grouvelle, 1899) comb. nov. South Africa: W and E Cape

Chromogethes illustroides (Audisio & De Biase, 2004) South Africa: KwaZulu-Natal, Free State comb. nov.

Chromogethes involutus ( Kirejtshuk, 2001) comb. nov. South Africa: KwaZulu-Natal, Mpumalanga, Lesotho Chromogethes longiceps (Easton, 1959) comb. nov. Ethiopia

Chromogethes malkini ( Spornraft & Kirejtshuk, 1994) South Africa: W and E Cape comb. nov.

Chromogethes mastax (Audisio & De Biase, 2004) South Africa: KwaZulu-Natal, Free State comb. nov.

Chromogethes paropunctatus (Kirejtshuk, 1995) comb. nov. South Africa: W Cape

Chromogethes perpusillus ( Spornraft & Kirejtshuk, 1993) South Africa: W and E Cape comb. nov.

2) In a recent contribution on some southern African species of Meligethes (subg. Chromogethes ), M. (C.) albens Audisio & De Biase, 2004 was described obviously overlooking the previous description (in Russian) of Meligethinus formosus Kirejtshuk, 1989 , erroneously originally attributed, in fact, to a relatively distantly related genus. Therefore, the new synonymy is established here.

Chromogethes profundopunctatus ( Kirejtshuk, 2001) South Africa: KwaZulu-Natal, Mpumalanga, E Free comb. nov. State

Chromogethes schulzei ( Kirejtshuk, 2001) comb. nov. South Africa: W and E Cape

Chromogethes sjoestedti ( Grouvelle, 1910) comb. nov. Tanzania, Kenya, Uganda

Chromogethes splendidulus (Reitter, 1873) comb. nov. South Africa: W Cape

Chromogethes subcaeruleus ( Grouvelle, 1910) comb. nov. Tanzania, Kenya, Uganda

Chromogethes subillustris (Kirejtshuk, 1995) comb. nov. South Africa: KwaZulu-Natal, Mpumalanga Chromogethes venustus (Kirejtshuk, 1988) comb. nov. South Africa: KwaZulu-Natal, E Cape Chromogethes violascens ( Kirejtshuk, 2001) comb. nov. Ethiopia

Chromogethes viridicolor ( Spornraft & Kirejtshuk, 1993) South Africa: E Cape comb. nov.

Chromogethes vitabundus ( Kirejtshuk, 2001) comb. nov. Tanzania

Chromogethes voluptarius ( Kirejtshuk, 1989) comb. nov. South Africa: E Cape

Chromogethes vulpinoides (Audisio & De Biase, 2004) South Africa: W Cape comb. nov.

Chromogethes vulpinus ( Spornraft & Kirejtshuk, 1993) South Africa: KwaZulu-Natal, Mpumalanga comb. nov.

Species ‘ incertae sedis ’ likely related to Chromogethes . The following Meligethinae taxa from the Indian Subcontinent, thus far classified as Meligethes s. l., have not been attributed with certainty to any of the herein discussed genera. Both species are probably not distantly related to Chromogethes , however a separate, new genus may need to be erected to accommodate them. Pending more detailed morphological analyses, field data on larval biology, and molecular data, we are unable to insert these taxa in this new preliminary taxonomic classification.

‘ Meligethes ’ micros Kirejtshuk, 1980 Sri Lanka

‘ Meligethes ’ topali Kirejtshuk, 1988 India

Figures

Fig. 2. Asterogethes Audisio & Cline, gen. nov.: a – A. endroedyi (Kirejtshuk & Audisio, 1995); b–d, f–n – A. arcuatus (Reitter, 1872); e – A. rufiventris (Reitter, 1872). a, b – male habitus (a – length 3.2 mm; b – length 2.4 mm); c – dorso-lateral view of head; d – ventral view of head and anterior portion of prosternum; e – outline of male metafemur (length 0.5 mm); f – caudal marginal lines of metacoxal cavities; g – exposed portion of last visible abdominal ventrite; h – middle leg with illustrating outer margin of mesotibia; k – antenna; m – pronotal setae and microsetae on posterior margin of pronotum; n – prosternal process and mesoventrite. Scale bars: Figs. c, h, m, n = 20μm; Figs. d, f, g = 100 μm.

Fig. 3. Odontholariopsis Audisio & Cline, gen. nov.: a, g – O. haagii (Reitter, 1872); b–f, h – O. nebulosus (Reitter, 1872). a – male habitus (length 2.6 mm); b – dorsal view of head; c – ventral view of head and anterior portion of prosternum; d – middle leg illustrating outer margin of mesotibia; e – scutellum and microsetae on posterior margin of pronotum; f – prosternal process and mesoventrite; g – outline of male metafemur (length 0.5 mm); h – exposed portion of last visible abdominal ventrite. Scale bars: Figs. b, c, f, h = 100 μm; Fig. d = 30 μm; Fig. e = 20 μm.

Fig. 4. Lariopsis Kirejtshuk, 1989: a – L.vultuosus (Kirejtshuk & Audisio, 1995); b–k – L. variabilis (Reitter, 1872). a – male habitus (length 3.3 mm); b, c – dorso-lateral view of head; d – ventral view of head and anterior portion of prosternum; e – prosternal process and mesoventrite; f – middle leg with outer margin of mesotibia; g – microsetae on middle posterior margin of pronotum; h – exposed portion of last visible abdominal ventrite; k – caudal marginal lines of metacoxal cavities. Scale bars: Figs. b, c, d, e, h, k = 100 μm; Fig. f = 30 μm; Fig. g = 10 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. 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. 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. 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. 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.