Bellascelis, Gimmel & Leschen, 2022

Gimmel, Matthew L. & Leschen, Richard A. B., 2022, Revision of the genera of Picrotini (Coleoptera: Cryptophagidae: Cryptophaginae), Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 62 (1), pp. 61-109 : 70-72

Bellascelis gen. nov.

( Figs 9–11 , 99 )

Type species. Bellascelis pecki sp. nov., by present designation.

Diagnosis. This genus is easily recognized among Picrotini by having abdominal ventrites 1 and 2 connate, the antennal club consisting of three antennomeres, and by the pronotal anterior angles being sharply right-angled. Additionally, the known species have the elytra diffusely to distinctly maculate and with a long, decumbent setae in a strongly undulate pattern.

Description. Length 1.47–1.60 mm. Body form ( Figs 9–11 ) elongate to subfusiform, somewhat shining dorsally, with long, dense, decumbent setae and with a few long erect setae dorsally; distinctly multicolored. Head with tempora absent or prominent, length when present about 1/5 length of eye; vertex with temporal depression immediately anterior to ridge; band of reticulate sculpture absent. Frontoclypeus not projecting laterally; raised portion of frons between antennal insertions not constricted, about as wide or wider than antennal club. Transverse ridge above antennal insertions absent. Eye large, rounded, contacting antennal cavity; interfacetal setae present. Antennal club consisting of 3 antennomeres; antenna inserted into small cavity; antennomere 9 subequal in width to antennomere 10. Mandible with apex bifid, subapical serrations present. Maxillary palpomere 4 distinctly longer than 3; palpomere 4 not subulate. Gena without antennal groove; genal spines obtuse. Gular sutures incomplete, not reaching occipital foramen. Pronotum not explanate, narrower than elytra and not constricted at base, widest at middle or in basal 1/3; anterior angles present, extending anterior to cervical foramen of prothorax, without a distinct flat glandular surface or platform; lateral carina complete, smooth, lacking teeth, crenulations, or setigerous tubercles, with lateral glabrous space narrow, width of lateral bead wider than discal puncture and narrower than antennal funicle; disc with basal transverse impression present; paramedial carinae present, paralateral plicae absent; posterolateral angles about right angled or slightly obtuse. Prothoracic hypomeron fused to prosternum. Prosternum with anterior margin on same plane as disc; prosternal process with lateral beads weak, mostly parallel then converging to acute point apically, process slightly expanded apically, broadly rounded and crenulate with minute setae; procoxal cavity with anterolateral notch. Scutellar shield clearly visible, transverse. Elytron without humeral tooth; subbasal and subapical impressions absent; subapical gape present; punctation confused, dense and moderately to weakly impressed; vestiture dual with a long, sparse, erect setae present, decumbent setae forming undulate pattern, with postscutellar and subapical setae directed laterally. Hind wing well developed. Mesoventrite with mesoventrital cavity shallow and flanked by sharp carinae. Mesanepisternal pit present and glabrous. Metaventrite without postcoxal lines; discrimen less than 1/2 length of metaventrite, posterior notch of metaventrite present. Metendosternite with anterior tendons approximate. Tarsi 5-5- 5 in female, 5-5- 4 in male; tarsi moderately slender, tarsomere 5 as wide as preceding tarsomeres in lateral view; pro- and mesotarsomere 4 with at least one seta; mesotarsomere 3 unlobed, with few setae; mesotarsomeres 1–4 of subequal lengths, mesotarsomere 5 about as long as mesotarsomeres 1–4 combined. Abdominal ventrites 1 and 2 connate without medial calli, lateral calli present, intersegmental crenulations absent; ventrite 1 with intercoxal process narrowly rounded, with scalloped postcoxal lines; medio-basal thickenings of ventrites 3–5 present; apex of ventrite 5 lacking crenulations.Abdominal spiracles on segment VII lacking opening, texture granulate and atrium rounded and saclike. Aedeagus (based on B. pecki only; Fig. 99 ) with tegminal strut absent, tegminal arms fused, with a suture; parameres separate and articulated to phallobase, inner surface concave, length about 2× longer than wide; apices multisetose; attachment point to phallobase not constricted, interparameral process present; basipenis 3× longer than distipenis, without median carina; distipenis relatively short (about 1.2× longer than wide), outer rims crenulate, lateral lobes not widely separated, symmetrical; internal sac lacking endophallites.

Remarks. In addition to the type species described below ( Fig. 9 ), we have seen three additional undescribed species from Australia, two of which ( Figs 10, 11 ) are featured in the gallery of dorsal habitus images. Characters of these are incorporated into the generic description above.

Etymology. The generic name is derived from a combination of the Latin prefix “ bellus ”, meaning “pretty”, in reference to the attractive facies of the included species, and “ -scelis ”, a common genus ending in Cryptophagidae . The gender is masculine.

Biology. Members of the genus have been collected commonly in leaf litter samples and flight intercept traps. One species has been collected in alpine pitfall traps.

Distribution. Australia.

Included species (1+3). Bellascelis pecki sp. nov.; three undescribed species from Australia.

Figures

Figs 1–9. Habitus of species of Picrotini. 1 – Agnetaria pilosella (Blackburn, 1891); 2 – Antarcticotectus rutilus (Broun, 1880); 3 – Antarcticotectus silvanus (Broun, 1880); 4 – Antarcticotectus tasmanicus (Blackburn, 1907); 5 – Antarcticotectus n. sp. 1 (New Zealand); 6 – Austroscelis gibbipennis (Blackburn, 1892); 7 – Austroscelis n.sp.1 (Australia:NSW, Vic); 8 – Austroscelis n.sp. 2 (Australia:WA); 9 – Bellascelis pecki sp.nov. Scale bars = 1 mm.

Figs 10–18. Habitus of species of Picrotini. 10 – Bellascelis n. sp. 1 (Australia: Qld); 11 – Bellascelis n. sp. 2 (Australia: NSW); 12 – Chileothortus infuscatus sp. nov.; 13 – Chiliotis sp. 1; 14 – Chiliotis sp. 2; 15 – Chiliotis sp. 3; 16 – Chiliotis sp. 4; 17 – Chiliotis sp. 5; 18 – Chimaerocryptus johnsoni sp. nov. Scale bars = 1 mm.

Figs 98–103.Aedeagus, dorsal view. 98 – Austroscelis gibbipennis (Blackburn, 1892); 99 – Bellascelis pecki sp. nov.; 100 – Cordosomatula magnabagishae sp. nov.; 101 – Humerocryptus n. sp. 1; 102 – Notocryptus australis (Redtenbacher, 1868); 103 – Orthoscelis transversus sp. nov. Abbreviations: aet = anterior extension of tegmen; as = apical serrations; bk = basal kink of internal sac; ep = endophallites; ics = inner concave surface; ip = interparameral plate; lf = lateral fold; os = ostium; pg = primary gonopore.