Olibrus Erichson, 1845

Gimmel, Matthew L., 2013, <strong> Genus-level revision of the family Phalacridae (Coleoptera: Cucujoidea) </ strong>, Zootaxa 3605 (1), pp. 1-147 : 75-81

19. Olibrus Erichson, 1845

( Figs. 3e ; 22 ; 41a )

Olibrus Erichson 1845: 113 . Type species: Sphaeridium bicolor Fabricius 1792 , fixed by subsequent designation.

Idiobius Gistel 1856: 383 . Type species: Phalacrus flavicornis Sturm 1807 , designated by Pakaluk et al. (1994: 229). [synonymized with Olibrus by Pakaluk et al. 1994: 229]

Type material. Sphaeridium bicolor Fabricius : two syntypes, not seen ( ZMUC). Phalacrus flavicornis Sturm : type not seen.

Diagnosis. This genus may be recognized by metatarsomere I shorter than metatarsomere II, metaventral process protruding anteriorly, protibia without ctenidium (but with up to 4 spines), no spectral iridescence on elytra but rather with a greasy luster, antennomere 11 turbinate (sometimes weakly so), and female ovipositor distinctive (modified into a double-pointed wedge with styli arising subapically and pointing laterally).

Description. Very small to large, total length 1.1–3.9 mm. Color highly variable, from completely testaceous to completely black, often with metallic greenish or bluish luster, dark specimens sometimes with subapical yellow or red maculations ( Fig. 41a ). Tibial spur formula 2-2-2, tarsal formula 5-5- 5 in females, 5-5-5 or 5-5- 4 in males.

Head. Not constricted behind eyes. Eyes medium-sized; facets flat; interfacetal setae absent; weakly emarginate or straight medially; without posterior emargination; periocular groove present or absent; with transverse setose groove ventrally behind eye. Frontoclypeus emarginate above antennal insertion; clypeal apex arcuate-truncate. Antennal club 3-segmented, club weakly asymmetrical, antennomere XI weakly to strongly turbinate ( Fig. 22b ). Mandible ( Fig. 22a ) slender; apex tridentate; without retinaculum; mandible without ventral ridge. Maxillary palpomere IV fusiform, nearly symmetrical; galea short, rounded; lacinia with two stout spines. Mentum with sides divergent toward apex; labial palpomere III fusiform, pointed or not apically. Labrum with apical margin truncate. Gular sutures short, barely evident.

Thorax. Pronotum without obvious microsetae; with moderately developed scutellar lobe. Prosternum anteriorly with continuous row of marginal setae, setae flattened at base; procoxal cavity with anterolateral notchlike extension; prosternal process rounded in lateral view, not conspicuously setose preapically, without spinelike setae at apex. Protrochanter with setae; protibia without ctenidium on kickface ( Fig. 22c ), but with group of up to four spines at outer apical angle; male protarsomere II sometimes expanded. Scutellar shield small. Elytron usually without spectral iridescence, often with brassy or aeneous luster, iridescent in some southern African species; usually two sutural striae present, sometimes only one, occasionally with quite short third stria in apical third; discal striae sometimes weakly developed, with parallel rows of punctures; without transverse strigae; lateral margin with row of tiny, sawtooth-like setae. Mesoventral plate ( Fig. 22f ) notched anteriorly, extending posteriorly to metaventrite, dividing mesoventral disc in two, not forming procoxal rests; mesanepisternum with complete or incomplete transverse carina; mesocoxal cavities widely separate, separated by more than half width of a coxal cavity. Mesotarsomere III bilobed. Metaventral process ( Fig. 22f ) extending at least to anterior level of mesocoxae, often protruding and arcuately lobed anteriorly; metaventral postcoxal lines not separated from mesocoxal cavity margin; discrimen quite short, extending much less than halfway to anterior margin of metaventral process; metendosternite ( Fig. 22g ) 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 roughly perpendicular overall to long axis of tibia; spurs cylindrical, longest spur subequal in length to width of tibial apex; metatarsomere I shorter than metatarsomere II, joint between I and II flexible ( Fig. 22d ); metatarsomere III bilobed. Hind wing ( Fig. 22e ) with distinct, ovate anal lobe; leading edge with complete row of long setae at level of RA +ScP; AA 3+4 strong and complete, or faint, sometimes connected to Cu by AA 3; cubitoanal system branched apically; CuA 2 and MP 3+4 with distal remnants; r4 absent or weakly developed, not connected with RA 3+4; conspicuous flecks absent from apical field distal to rp-mp2, or with extremely short fleck proximally; long transverse proximal sclerite and sometimes additional small oblique sclerite present just distal to end of radial bar.

Abdomen. Abdominal ventrite I without paired lines or calli; spiracles present and apparently functional on segment VII. Male with aedeagus upright in repose; tegmen ( Fig. 22h ) with symmetrical or asymmetrical anterior margin and parameres separated by suture from basal piece, parameres with or without medial longitudinal division; penis ( Fig. 22i ) with subapical paired endophallic sclerites, apex simple or weakly bilobed; spiculum gastrale V-shaped, with arms free. Female ovipositor ( Fig. 3e ) sclerotized, gonocoxites together forming wedge, gonostyli attached subapically.

Immature stages. Laboulbéne (1868) described the larva of O. affinis (Sturm) and its habits. Urban (1926, 1930) described the larvae of Olibrus aeneus (Fabricius) and O. millefolii (Paykull) . Löben Sels (1934) described the larva and pupa of a Nearctic Olibrus (as Phalacrus politus Melsheimer ).

Bionomics. At least in the Holarctic region and southern Africa, members of this genus are diurnal and visit flowers of various plants (especially Asteraceae ) as adults. As larvae, they are more host specific, developing within the flower heads of particular composites, including Solidago , Symphyotrichum , Achillea , Chrysopsis , Helichrysum , Tragopogon , Senecio , Hypochaeris , Matricaria , Anthemis , Leontodon , and Crepis . The larvae feed with their heads pointed downward among the disc flowers of the flower head, and their presence is often evidenced by a tuft of pappus protruding above the level of the flower disc. They appear to feed only on fluids, as no particulate matter has been observed in the gut. In flower heads of Symphyotrichum novae-angliae (L.) G.L. Nesom, in Kansas, I discovered anywhere from four to nine larvae living inside each head. Members of Olibrus have been considered as biological control agents of certain weedy Asteraceae , including O. aeneus for the introduced European Tripleurospermum perforatum (Mérat) Wagenitz in Canada (see Freese and Günther 1991). Flower heads fed upon by the beetles tend to be destroyed, but the potential utility of the beetle is compromised by its oligophagous nature.

Among non-Asteraceae occurrences, specimens were collected by D. Habeck in Queensland (FSCA) on flowers and foliage of the cajeput tree, Melaleuca linariifolia Sm. (Myrtaceae) . In South Africa, some were collected by beating a species of Acacia .

Distribution and diversity. One of the few genera occurring in both New and Old Worlds, it occurs in North America from southern Canada south to at least the Mexican states of México and Tlaxcala. I have seen no specimens of true Olibrus from the West Indies. In the Old World it occurs throughout the Palearctic Region, and also in eastern and southern Africa (excluding wet tropical regions), the Oriental Region, and at least to Queensland and Western Australia.

Olibrus is currently the largest genus in Phalacridae in terms of described species. Many (especially Oriental) species will probably be removed from this genus after the appropriate types are examined. The Nearctic fauna is probably severely over-described (notably by Thomas L. Casey) and many of the species names are likely to be synonyms. The South African Olibrus fauna is exceedingly rich, and if any lineage of the Phalacridae is to be regarded as an adaptive radiation, it is this one.

Included species (128):

Olibrus abstinens Casey, 1916 ( Distribution : United States) (type!)

Olibrus aenescens Küster, 1852 (Distribution: western Mediterranean)

Olibrus aeneus (Fabricius, 1792) (Distribution: Palearctic)

Olibrus aeratus (Champion, 1925) (Distribution: South Africa) (type!)

Olibrus affinis (Sturm, 1807) (Distribution: Palearctic) (type!)

Olibrus albomaculatus Motschulsky, 1858 (Distribution: southeast Asia) [NOTE: may not belong in Olibrus ] Olibrus anthobius Guillebeau, 1894 (Distribution: Ethiopia) (type!)

Olibrus aridus Casey, 1916 ( Distribution : United States) (type!)

Olibrus bakeri Casey, 1916 ( Distribution : United States) (type!)

Olibrus baudueri Tournier, 1888 (Distribution: western Palearctic)

Olibrus bedeli Guillebeau, 1892 (Distribution: northern Africa)

Olibrus bevinsi Champion, 1925 ( Distribution : South Africa) (type!)

Olibrus bicolor (Fabricius, 1792) (Distribution: Palearctic)

Olibrus bimaculatus Küster, 1848 (Distribution: Palearctic)

Olibrus bisignatus (Ménétries, 1849) (Distribution: Palearctic)

Olibrus bivulnerus Motschulsky, 1858 (Distribution:? Sri Lanka) [NOTE: may not belong in Olibrus ]

Olibrus blanditus Casey, 1916 ( Distribution : United States) (type!)

Olibrus bohemani Champion, 1925 ( Distribution : South Africa) (type!)

Olibrus brunneus ( Motschulsky, 1858) (Distribution: Sri Lanka, Taiwan) [NOTE: may not belong in Olibrus ] Olibrus bullatus Casey, 1916 (Distribution: United States) (type!)

Olibrus calamis Casey, 1916 ( Distribution : United States) (type!)

Olibrus callidus Casey, 1916 ( Distribution : United States) (type!)

Olibrus calvosus Lyubarsky, 2003 (Distribution: Nepal) [NOTE: may not belong in Olibrus ]

Olibrus camptoides Reitter, 1892 (Distribution: “Turkestan”)

Olibrus capensis (Guérin-Méneville, 1844) , comb. nov. ( Tolyphus ) (Distribution: South Africa)

Olibrus caseyi Hetschko, 1930 ( Distribution : United States) (type!)

Olibrus castaneus Baudi di Selve, 1870 (Distribution: Mediterranean region)

Olibrus caucasicus Tournier, 1889 ( Distribution : Mediterranean region) (type!)

Olibrus cessus Casey, 1916 ( Distribution : United States) (type!)

Olibrus cinerariae Wollaston, 1854 (Distribution: Madeira)

Olibrus collucens Casey, 1916 ( Distribution : United States) (type!)

Olibrus congener Wollaston, 1864 (Distribution: Canary Islands)

Olibrus consanguineus Flach, 1889 (Distribution: Japan)

Olibrus corticalis (Panzer, 1797) (Distribution: western Palearctic)

Olibrus decoloratus Casey, 1916 ( Distribution : United States) (type!)

Olibrus delicatulus Tournier, 1889 ( Distribution : Russia) (type!)

Olibrus demarzoi Švec & Angelini, 1996 (Distribution: Italy, Turkey)

Olibrus desbrochersi Guillebeau, 1892 (Distribution: western Mediterranean)

Olibrus egenus Guillebeau, 1896 ( Distribution : Madagascar) (type!)

Olibrus evanescens Champion, 1925 ( Distribution : South Africa) (type!)

Olibrus fallaciosus Casey, 1916 ( Distribution : United States) (type!)

Olibrus fallax Flach, 1888 (Distribution: Austria, Italy)

Olibrus festivus Lyubarsky, 2005 ( Distribution : South Africa) (type!)

Olibrus firmus Lyubarsky, 2003 (Distribution: Nepal) [NOTE: may not belong in Olibrus ]

Olibrus flachi Reitter, 1891 (Distribution: Kazakhstan, Uzbekistan)

Olibrus flavicornis (Sturm, 1807) (Distribution: Palearctic)

Olibrus florum Wollaston, 1854 (Distribution: Canary Islands)

Olibrus frustratus Casey, 1916 ( Distribution : United States) (type!)

Olibrus gemma Wollaston, 1867 (Distribution: Cape Verde)

Olibrus gerhardti Flach, 1888 (Distribution: Europe)

Olibrus globiformis Tournier, 1894 ( Distribution : Turkey) (type!)

Olibrus guttatus Tournier, 1889 ( Distribution : western Palearctic) (type!)

Olibrus hervosus Lyubarsky, 1994 (Distribution: Borneo, India, Philippines) [NOTE: may not belong in Olibrus ]

Olibrus igneus Fauvel, 1903 (Distribution: New Caledonia) [NOTE: probably does not belong in Olibrus ]

Olibrus impotens Casey, 1916 ( Distribution : United States) (type!)

Olibrus impressus Hatch, 1962 (Distribution: United States)

Olibrus irregularis Casey, 1916 ( Distribution : United States) (type!)

Olibrus jelineki Švec & Ponel, 1999 (Distribution: Turkey)

Olibrus judaicus Sahlberg, 1913 (Distribution: Israel)

Olibrus kaszabi Medvedev, 1971 (Distribution: Mongolia)

Olibrus koltzei Flach, 1888 (Distribution: central Palearctic)

Olibrus laevisternus Guillebeau, 1897 (Distribution: Syria)

Olibrus latisternus (Guillebeau, 1893) , comb. nov. ( Litochrus ) ( Distribution : Vietnam) (type!)

Olibrus latisternus Guillebeau, 1894 ( Distribution : Oriental) (type!) [junior secondary homonym not replaced, pending further investigation]

Olibrus lecontei Casey, 1890 ( Distribution : United States) (type!)

Olibrus liquidus Erichson, 1845 (Distribution: western Palearctic)

Olibrus lubricatus Lyubarsky, 2004 (Distribution: Nepal) [NOTE: may not belong in Olibrus ]

Olibrus lubricus Casey, 1916 ( Distribution : United States) (type!)

Olibrus macropus Champion, 1925 ( Distribution : South Africa) (type!)

Olibrus metallescens Flach, 1888 (Distribution: Mongolia, Russia)

Olibrus millefolii ( Paykull, 1800) (Distribution: Palearctic)

Olibrus minusculus Motschulsky, 1866 (Distribution: Sri Lanka) [NOTE: may not belong in Olibrus ]

Olibrus motschulskyi Lyubarsky, 1994 (Distribution: Sri Lanka) [NOTE: may not belong in Olibrus ]

Olibrus multesimus Lyubarsky, 1994 (Distribution: Oriental) [NOTE: may not belong in Olibrus ]

Olibrus nainiensis Champion, 1924 ( Distribution : India, Indonesia, Philippines) (type!)

Olibrus namibiensis Lyubarsky, 1998 (Distribution: Namibia, South Africa)

Olibrus natalensis Champion, 1924 ( Distribution : South Africa) (type!)

Olibrus neglectus Casey, 1890 ( Distribution : United States) (type!)

Olibrus nigroclavatus Champion, 1925 ( Distribution : South Africa) (type!)

Olibrus norvegicus Münster, 1901 (Distribution: Palearctic)

Olibrus notatus Wollaston, 1867 (Distribution: Cape Verde)

Olibrus obscuricornis Guillebeau, 1894 ( Distribution : India) (type!)

Olibrus obscurus Guillebeau, 1892 (Distribution: Italy, Slovakia)

Olibrus ovalis Khnzorian, 1962 (Distribution: Armenia)

Olibrus pallidulus Motschulsky, 1858 (Distribution: Sri Lanka) [NOTE: may not belong in Olibrus ]

Olibrus pallipes (Say, 1824) (Distribution: United States)

Olibrus particeps Mulsant & Rey, 1861 (Distribution: Palearctic)

Olibrus peringueyi Gimmel , nom. nov. [for Olibrus consanguineus Péringuey, 1892 , junior primary homonym of Olibrus consanguineus Flach, 1889 ] (Distribution: South Africa)

Olibrus permicans Reitter, 1913 (Distribution: China)

Olibrus platycephalus Champion, 1924 (Distribution: India) (type!) [NOTE: may not belong in Olibrus ] Olibrus platysternus Champion, 1925 (Distribution: Namibia, South Africa) (type!)

Olibrus pondoensis Champion, 1925 ( Distribution : Namibia, South Africa) (type!)

Olibrus pruddeni Casey, 1916 ( Distribution : United States) (type!)

Olibrus punctatus Lyubarsky, 1994 (Distribution: Borneo) [NOTE: may not belong in Olibrus ]

Olibrus pygmaeus (Sturm, 1807) (Distribution: western Palearctic)

Olibrus quadristriatus Champion, 1925 ( Distribution : South Africa) (type!)

Olibrus raffrayi Guillebeau, 1894 ( Distribution : Ethiopia) (type!)

Olibrus rasilis Lyubarsky, 2003 (Distribution: Nepal)

Olibrus reitteri Flach, 1888 (Distribution: Mediterranean)

Olibrus reyi Guillebeau, 1892 (Distribution: Greece)

Olibrus rufescens Motschulsky, 1858 (Distribution: Indonesia, Sri Lanka) [NOTE: may not belong in Olibrus ] Olibrus rufipes LeConte, 1856 (Distribution: Canada, United States) (type!)

Olibrus rufopiceus Motschulsky, 1858 (Distribution: Japan, Sri Lanka) [NOTE: may not belong in Olibrus ] Olibrus rufoplagiatus Champion, 1925 (Distribution: South Africa) (type!)

Olibrus rufosignatus Lyubarsky, 1998 (Distribution: Namibia)

Olibrus rufoterminatus Champion, 1925 ( Distribution : Namibia, South Africa, Zimbabwe) (type!)

Olibrus seidlitzii Flach, 1888 (Distribution: Mongolia, Russia)

Olibrus selvei Guillebeau, 1892 (Distribution: Cyprus)

Olibrus semistriatus LeConte, 1856 ( Distribution : Canada, United States) (type!)

Olibrus singularis Tournier, 1889 (Distribution: Morocco, Spain)

Olibrus snizeki Švec, 2005 (Distribution: Kenya)

Olibrus sternalis Casey, 1916 , resurrected name ( Distribution : United States) (type!)

Olibrus stictus Lyubarsky, 1994 (Distribution: Oriental) [NOTE: may not belong in Olibrus ]

Olibrus stierlini Flach, 1888 (Distribution: western Palearctic)

Olibrus stlatarius Lyubarsky, 1994 (Distribution: Indonesia, Philippines) [NOTE: may not belong in Olibrus ] Olibrus stlembus Lyubarsky, 1994 (Distribution: Nepal, Philippines) [NOTE: may not belong in Olibrus ] Olibrus striatissimus Reitter, 1899 (Distribution: Azerbaijan, Iran)

Olibrus stuporatus Lyubarsky, 1994 (Distribution: Indonesia, Nepal) [NOTE: may not belong in Olibrus ] Olibrus subaereus Wollaston, 1864 (Distribution: Canary Islands)

Olibrus tangerianus Tournier, 1889 (Distribution: Morocco)

Olibrus tolyphoides Champion, 1925 ( Distribution : South Africa) (type!)

Olibrus turcicus Švec & Ponel, 1999 (Distribution: Turkey)

Olibrus utealis Casey, 1916 ( Distribution : United States) (type!)

Olibrus veteratus Lyubarsky, 2003 (Distribution: Indonesia, Vietnam) [NOTE: may not belong in Olibrus ] Olibrus viridescens Champion, 1925 (Distribution: South Africa) (type!)

Olibrus vittatus LeConte, 1863 ( Distribution : Canada, United States) (type!)

Olibrus voraginalis Casey, 1916 ( Distribution : United States) (type!)

Olibrus wickhami Casey, 1890 ( Distribution : United States) (type!)

Discussion. Motschulsky’s and Lyubarsky’s Oriental species of Olibrus , treated by Lyubarsky (1993 a, b, 1994 a, 2003), have not been examined by me. Lyubarsky’s concept of this genus was much broader than that presented here. Additionally, his drawings and descriptions tend to be sparse and schematic, and do not necessarily emphasize diagnostic characters. Therefore, species described by these authors are only provisionally retained in Olibrus , with the exception of one species, Olibrus brunnescens Motschulsky, 1858 , which I have transferred to Stilbus Seidlitz based on the distinctive aedeagus illustrated in Lyubarsky (1993 b). Lyubarsky’s (1998, 2005) African species are more clearly illustrated, and certain of his species have been transferred out of Olibrus by Švec (2002, 2003). I have provisionally transferred O. capriviensis Lyubarsky, 1998 to Acylomus Sharp.

The large, striking species Olibrus capensis Guérin-Méneville , from South Africa, was transferred to Tolyphus (Pharcisinus) by Champion (1925 a) without explanation. I have examined material of this species (BMNH, SANC) and it properly belongs in Olibrus .

Upon examination of the types of Olibrus bullatus Casey, 1916 , and O. sternalis Casey, 1916 , I have determined these are probably not synonymous. The elytra differ in the extent of microsculpture. While many of Casey’s names in Olibrus are certainly junior synonyms, I have chosen to resurrect O. sternalis so that it may be properly placed in future.

Figures

FIGURE 3. Key characters for Phalacridae. (a) Prosternal process of Acylomus aciculatus Sharp (scale bar = 0.5 mm). (b) First abdominal ventrite of Malagophytus steineri Gimmel. Ovipositor of (c) Phalacrus sp.; (d) Phalacropsis dispar (LeConte); (e) Olibrus aeneus (Fabricius); (f) Litostilbus testaceus (Fabricius) (scale bars = 0.5 mm).

FIGURE 22. Olibrus aeneus, male. (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 = 0.5 mm). (g) Metendosternite (scale bar = 0.5 mm). (h) Tegmen, ventral; (i) penis, ventral (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.