Olibrosoma Tournier, 1889

Gimmel, Matthew L., 2013, <strong> Genus-level revision of the family Phalacridae (Coleoptera: Cucujoidea) </ strong>, Zootaxa 3605 (1), pp. 1-147 : 91-92

23. Olibrosoma Tournier, 1889

( Figs. 26 ; 41e )

Olibrosoma Tournier 1889: 83 . Type species: Olibrosoma testacea Tournier 1889 , fixed by monotypy.

Helectrus Guillebeau 1892 b: 147 . Type species: Helectrus brisouti Guillebeau 1892 , fixed by original designation.

Pyracoderus Guillebeau 1892 b: 148 . Type species: Pyracoderus lemoroi Guillebeau 1892 , fixed by original designation.

Litochroides Guillebeau 1892 b: 148 . Type species: Litochroides sharpi Guillebeau 1892 , fixed by original designation.

Lichrotus Liubarsky 1993 a: 17, as subgenus of Litochrus Erichson. Type species: Litochrus strigosus Reitter 1899 , fixed by monotypy. Syn. nov.

Type material. Olibrosoma testacea Tournier : lectotype, male, “water soluble // Egypte // [illegible] // Olibrosoma testaceum // Peyer. vidi // TYPE // Museum Paris, \ collection genérale // Lectotypus \ OLIBROSOMA TESTACEA Tourn. 1889 \ Z. Svec des. 1999” ( MNHN), genitalia dissected.

Helectrus brisouti Guillebeau : type not seen.

Pyracoderus lemoroi Guillebeau : type not seen.

Litochroides sharpi Guillebeau : type not seen.

Litochrus strigosus Reitter : type not seen.

Diagnosis. The only phalacrid (except for an undescribed species of Pycinus from Brazil) whose antennal club contains more than three segments. Additionally, metatarsomere I is much longer than metatarsomere II, the metaventral process reaches about the anterior level of the mesocoxae, and the scutellar shield is narrower than the width of an eye.

Description. Medium-sized to large, total length 2.0– 3.5 mm. Dorsal color solid testaceous to piceous ( Fig. 41e ), darker specimens usually with lighter elytral apices. Tibial spur formula 2-2-2, tarsal formula 5-5- 4 in both sexes.

Head. Not constricted behind eyes. Eyes large; facets convex; interfacetal setae absent; deeply emarginate medially; without posterior emargination; periocular groove present; with transverse setose groove ventrally behind eye. Frontoclypeus emarginate above antennal insertion; clypeal apex arcuate-truncate. Antennal club 4- segmented, antennomere VII usually broadly triangular, so that club may appear 5-segmented, club weakly asymmetrical; antennomere XI weakly turbinate ( Fig. 26b ). Mandible ( Fig. 26a ) with apex simple or tridentate; retinaculum absent; mandible without ventral ridge. Maxillary palpomere IV fusiform, nearly symmetrical; galea short, rounded; lacinia with two stout spines. Mentum parallel-sided; labial palpomere III weakly triangular, with apex relatively broad. Labrum with apical margin truncate. Gular sutures short, barely evident .

Thorax. Pronotum without obvious microsetae; with distinct scutellar lobe. Prosternum anteriorly with row of marginal setae distributed evenly, setae normal; procoxal cavity without anterolateral notchlike extension; prosternal process angulate in lateral view, not distinctly setose preapically, without spinelike setae at apex. Protrochanter with setae; protibia with ctenidium on kickface extending two-thirds to three-quarters length of tibia ( Fig. 26c ). Scutellar shield small, width at base shorter than length of eye. Elytron with or without spectral iridescence; with one sutural stria; with weak transverse strigae; lateral margin with row of tiny, sawtooth-like setae. Mesoventral plate ( Fig. 26f ) notched anteriorly, not extending posteriorly to metaventrite, forming procoxal rests, mesoventral disc sunken medially, with scattered setae; mesanepisternum with complete transverse carina; mesocoxal cavities separated by slightly more than half width of single coxal cavity. Mesotarsomere III not bilobed. Metaventral process ( Fig. 26f ) extending to about level of anterior margin of mesocoxae, truncate apically; metaventral postcoxal lines separated slightly from mesocoxal cavity margin, following cavity borders; discrimen short, extending less than halfway to anterior margin of metaventral process; metendosternite ( Fig. 26g ) with anterior tendons moderately separated, ventral process intersecting ventral longitudinal flange behind anterior margin. Anterior margin of metacoxa with emargination sublaterally; metacoxal plate without transverse line; metatibial foreface with apical ctenidium markedly oblique, oriented about 45° to long axis of tibia; spurs cylindrical, longest spur longer than width of tibial apex; metatarsus about as long as metatibia, metatarsomere I much longer than metatarsomere II, about as long as remainder of tarsus, joint between I and II rigid ( Fig. 26d ); metatarsomere III not bilobed. Hind wing ( Fig. 26e ) with distinct, ovate anal lobe; leading edge with incomplete row of long setae; AA 3+4 distinct, crossvein to Cu present; cubitoanal system forked apically; CuA 2 and MP 3+4 with distal remnants; r4 present, connecting RP with RA 3+4; large fleck present in apical field distal to rp-mp2; long transverse sclerite, horizontal sclerite, and large nebulous triangular sclerite present just distal to end of radial bar.

Abdomen. Abdominal ventrite I without paired lines, with calli; spiracles present and apparently functional on segment VII. Male with aedeagus upright in repose; tegmen with symmetrical anterior margin, parameres separated by suture from basal piece, parameres without medial longitudinal division; penis narrow, with pair of endophallic sclerites and fields of endophallic spicules, apex acutely pointed; spiculum gastrale with arms V-shaped, free apically, sometimes laminate basally, with short anterior extension. Female ovipositor weakly sclerotized, palpiform.

Immature stages. Unknown.

Bionomics. Peyerimhoff (1907) reports O. testacea from flowers of Phelipaea (= Orobanche , Orobanchaceae ) in Sinai. Label data are meager for the specimens I have examined but a series from Botswana was taken in a Malaise trap.

Distribution and diversity. Interestingly, the type species of this genus ranges in the hottest, driest deserts of North Africa and the Middle East, from Mauritania and Mali east across the Sahara to Saudi Arabia and Iran. I have seen a few undescribed species from Subsaharan Africa, south to South Africa. I have not seen the Reitter species.

Included species (2):

Olibrosoma strigosa ( Reitter, 1899) , comb. nov. (Distribution: “Transcaspien”)

Olibrosoma testacea Tournier, 1889 ( Distribution : North Africa, Middle East) (type!)

Discussion. I have tentatively synonymized Liubarsky’s (1993 a) subgenus Litochrus (Lichrotus) based purely on his and Reitter’s (1899) brief descriptions of the type species. The key character is a 4-segmented antennal club, which no other known Old World phalacrid possesses. The type species of Olibrosoma was redescribed by Švec (2010).

Figures

FIGURE 26. Olibrosoma testacea, female. (a) Left mandible, dorsal; (b) left antenna (scale bar = 0.5 mm). (c) Left protibia and tarsus, dorsal; (d) left metatibia and tarsus, ventral (scale bar = 0.5 mm). (e) Hind wing (scale bar = 1.0 mm). (f) Meso- and metaventrite, ventral (scale bar = 1.0 mm). (g) Metendosternite (scale bar = 0.5 mm).

FIGURE 41. Photographs. Olibrus sp.: (a) dorsal. Antennogasmus cordatus, holotype: (b) dorsal. Malagasmus thalesi, holotype: (c) dorsal; (d) ventral. Olibrosoma testacea: (e) dorsal. Apallodes sp.: (f) dorsal. Augasmus humilis: (g) dorsal; (h) ventral. Entomocnemus sp., southeast Asia: (i) dorsal.