Brounhister Leschen and Ôhara, 2017

Leschen, Richard A. B. & Ôhara, Masahiro, 2017, Phylogenetic Placement of Abraeus vividulus Broun and Notes on New Zealand Histeridae (Coleoptera), The Coleopterists Bulletin 71 (3), pp. 537-551 : 543-546

Brounhister Leschen and Ôhara , new genus

( Figs. 1 , 3– 7 , 8E )

Type Species. Abraeus vividulus Broun 1880: 166 .

Diagnosis. Antenna 9-segmented with 1-segmented club; vesicle present and irregularly septate. Gena bearing acute spines. Gular sutures posteriorly

divergent. Prosternum lacking transverse line; chin-piece present; antennal grooves present, internally open to apical third; pocket for antennal club formed by hypomeron and prosternum. Notosternal suture distinct, forming an anterior notch. Mesoventrite separated by sutures from mesanepisterna, procoxal and femoral rest present. Hindwing with R-M loop acute and a deep embayment. Protibia with protarsal groove reduced, protarsus resting at a more or less oblique angle at apex. Tarsi 5-5-5. Abdominal ventrite 1 with subcoxal lines. Phallobase asymmetrical, not fused to parameral tube and not forming a complete ring.

Description. Length 1.3–1.6 mm (mean = 1.3 mm). Body moderately convex ( Figs. 1A–C , 8E ), color tan (teneral?) to dark or reddish brown to black, glabrous, finely to coarsely punctate, punctures ovoid. Head with vertex declined with mouthparts directed ventrally. Supraorbital and frontal striae absent. Frons lacking carinae and frontal protuberance ( Fig. 3C ). Eyes entire, coarsely faceted, 7 (length) × 11 (width) ommatidia. Frontoclypeal suture absent. Antenna 9-segmented formed of scape, pedicel, 6 funicular antennomeres, and a large club composed of 3 fused antennomeres ( Fig. 5A ); insertions hidden beneath weak anterior ridge above eye; scape weakly curved; funicle glabrous; club pubescent with 2 annular creases ( Figs. 1A–C , 4A–C ), external sensilla vague, vesicle present and irregularly septate into at least 3–4 chambers ( Fig. 5B ). Labrum free and visible ( Fig. 3C ), transverse, width narrow, edge very weakly emarginate, bearing 2 major setae (1 at each corner). Mandibles with outer surface glabrous; incisor lobe acute (unidentate) and exposed in dorsal view in repose, with edge bearing 1 tooth; ventrally excavate with simple, setose prostheca; weakly striate mola present. Maxilla with relatively broad galea and narrow lacinia, setae simple and dense. Mentum ( Fig. 3B, E ) evenly arcuate and short with a medial invagination; terminal palpal segment not expanded or dorsoventrally flattened. Submentum with weak transverse line near anterior margin. Genae bearing acute spines. Gular sutures fused at midline, posteriorly divergent; laminatentorium well-developed and divided at middle.

Pronotum about 2X longer than wide, widest at base, moderately convex, anterior and posterior angles acute; bead present at anterior and lateral margins, lateral carina simple and complete, not sharply edged. Prosternum ( Fig. 3E, F ) in front of procoxae about as long as prosternal process, lacking transverse line (“suture”); chin-piece (= prosternal lobe or presternum) present and deflected ventrally, anteriorly beaded; prosternal process vaulted at middle (referred to as a broad “keel”), not parallel-sided, margined by striae distinct to apical third, weakly narrowed and emarginated posteriorly; mesoventral rest present apically (visible in dissections); antennal grooves present (“alae” laterally incised), internally open to apical third, margined by carinae and inner edge posteriorly curved laterad; pocket for antennal club formed by hypomeron and prosternum, completely visible in ventral view. Notosternal suture distinct and nearly complete (visible within pocket for club), forming anterior notch. Procoxae strongly transverse; protrochantin absent or fused entirely with coxa. Procoxal cavities partially closed by long postcoxal projections. Scutellar shield ( Fig. 1A ) visible, minute and triangular. Elytra about 1.2X as long as combined width and over 2X as long as pronotum; punctation confused to striate, discal striae faint laterally; epipleuron defined by slightly raised lateral line. Mesoventrite separated by sutures from mesanepisterna, procoxal and femoral rest present; mesanepisternum and epimeron fused and demarcated by an internal ridge, epimeron with well-developed profemoral cavity. Mesocoxal cavities circular, widely separated and opened laterally; mesotrochantin not visible. Mesometaventral junction simple. Metaventrite ( Fig. 3G, H ) with discrimen entire, postcoxal and femoral lines present, lacking fovea, setiferous sex patches, and tubercles. Hind coxae widely separated ( Fig. 3B ). Metanepisternum exposed and broad ( Figs. 1C , 3H ). Metacoxal cavities circular and widely separated. Metendosternite with basal stalk indistinct, arms widely separated and long, laminae and anterior arms absent. Hindwing present with long apical field; venation reduced with MP 1+2 present and R-M loop acute and a deep notch-like embayment delimiting anal lobe. Profemora without spinose outer margin or ctenidia.Protibia broad and flattened ( Fig. 5C, D ) with outer spinose margin and inner setose margin, lacking well-developed protarsal groove, with a line present along anterior face with tarsus more or less retracted at an oblique angle apically; meso- and metatibiae slender and spinose; apical spurs present. Tarsal formula 5-5-5, claws separated, of equal sizes, empodium reduced or absent with 2 very minute setae and small flattened membranes visible at apex of T5 (visible at high magnification in dissections).

Abdominal ventrite 1 with subcoxal lines ( Fig. 3B, H ). Abdominal terga I–III membranous, IV divided at middle and partially membranous; terga II–VI with spiracles (propygidium lacking spiracle), spiracle on tergite V contained within annulate chamber; tergite VII (pygidium) semicircular ( Fig. 3D ). Male terminalia ( Fig. 6A–E ) with tergite and sternite VIII relatively short and broad, sternite VIII apically divided and apically multisetose; tergite X entire, relatively short and weakly connected by a membrane to tergite IX, apically bisetose; tergite IX relatively elongate with fixed struts expanded anteriorly; spiculum gastrale (sternite IX) free, ligulate, relatively long and weakly asymmetrical.Aedeagus histeroid ( Fig. 6F, G ), consisting of a short, asymmetrical membranous phallobase that is not fused to form a complete ring; parameres and median lobe slender, longer than phallobase. Female sternite VIII with long, broad spiculum ventrale, tapered posteriorly. Ovipositor ( Fig. 7A–C ) long and somewhat broad, bursa saccular and spermatheca membranous (not observed in dissections); paraprocts (= hemi- or laterotergite IX) distinctly longer than coxites, lightly sclerotized except for anteriorly expanded baculi, coxites undivided ( Fig. 7D ), well-sclerotized and blunt with subapical styli ( Fig. 7E ).

Figures

Fig. 1. Brounhister vividulus, habitus. A) Dorsal view, B) Lateral view, C) Oblique lateral view.

Fig. 3. Brounhister vividulus. A) Dorsal habitus, B) Ventral habitus, C) Head and prothorax, ventral view, D) Pygidium, dorsal view, E) Pro- and mesosterna, F) Prosternum, G) Mesosternum, H) Mesoventrite, lateral view.

Fig. 4. Brounhister vividulus, antennomere 9. A) Antennal club, B) Apex, C) Subapex.

Fig. 5. Brounhister vividulus. A) Antenna, B) Antennal club showing internal vesicles, C) Protibia, anterior view, D) Protibia, posterior view.

Fig. 6. Brounhister vividulus, male. A) Tergite and sternite VIII, dorsal view, B) Tergite and sternite VIII, lateral view, C) Sternite VIII of a different specimen, dorsal view, D) Tergites IX and X, dorsal view, E) Tergites IX and X, lateral view, F) Aedeagus, dorsal view, G) Aedeagus, lateral view.

Fig. 7. Brounhister vividulus, ovipositor. A) Dorsal view, B) Ventral view, C) Lateral view, D) Gonocoxite, lateral view, E) Gonostylus, lateral view.

Fig. 8. Primary types and original labels pinned with Abraeus species. A, B) A. brouni, C, D) A. brunneus, E, F) A. vividulus.