Elateriformia (Coleoptera)

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J. F. Lawrence, A. M. Hastings, M. J. Dallwitz, T. A. Paine and E. J. Zurcher

DASCILLIDAE

(= Atopidae; including Karumiidae).

Classification. Polyphaga: Elateriformia.

Distribution. Dascillinae occur throughout the Northern Hemisphere and in Australia, but are apparently absent from Africa and tropical America (except for an undescribed species from the Greater Antilles). The greatest diversity of Dascillinae is in Asia. The genus Coptocera (= Cinnabarium) is known from central western Africa and southeastern Asia. Karumiines occur in the more arid parts of western North America, Mexico, temperate South America, North Africa and Eurasia.

Biogeographic regions: Nearctic, Palearctic, Neotropical, Afrotropical, Oriental, Australian.

Biology. Larvae of Dascillus and Notodascillus are found in the soil and apparently feed on roots; they resemble scarab grubs. At least some karumiines are known to be termitophiles, and similar habits may occur in all of them. It is likely that larvae occur in the soil, probably associated with subterranean termites.

Notes. The family Dascillidae has been very broadly defined in the past to include many taxa now placed in Ptilodactylidae, Psephenidae, Artematopodidae and even Scirtidae. As delimited here it corresponds to Dascillidae and Karumiidae of Crowson (1971).

References

Arnett, R. H., Jr. 1964. Notes on Karumiidae (Coleoptera). Coleopterists' Bulletin, 18: 65–68.

Crowson, R. A. 1971. Observations on the superfamily Dascilloidea (Coleoptera: Polyphaga), with the inclusion of Karumiidae and Rhipiceridae. Zoological Journal of the Linnean Society 50: 11–19.

Fairmaire, L. 1895. Descriptions d'un genre et de trois espèces de Coléoptères nouveaux. Bulletin de la Société Entomologique de France 1985: ccv-ccvi.

Lawrence, J. F. 1991. Dascillidae (Dascilloidea), pp. 369–370. IN: F. W. Stehr (ed.), Immature Insects. Vol. 2. Kendall/Hunt Publishing Co., Dubuque, Iowa.

Lohse, G. A. 1979. 39. Familie: Dascillidae, pp. 249–250. IN: H. Freude, K. W. Harde and G. A. Lohse (eds.), Die Käfer Mitteleuropas. Band 6. Diversicornia. Goecke & Evers, Krefeld.

Murray, A. 1868. List of Coleoptera received from Old Calabar, on the west coast of Africa (part). Annals and Magazine of Natural History (4) 2: 91–111.

O'Keefe, S. 2000. 42. Dascillidae. IN: R. H. Arnett, Jr., Jr. and M. C. Thomas (eds.), American Beetles. CRC Press, Gainesville, Florida (in press).

Paulus, H. F. 1972. Die systematische und phylogenetische Stellung der Karumiidae, mit einer Beschreibung von Escalerina serraticornis n. sp. aus S-Persien (Ins.: Coleoptera: Cantharoidea). Senckenbergiana Biologica, 53: 37–54.

Pic, M. 1914. Pars 58. Dascillidae, Helodidae, Eucinetidae. IN: S. Schenkling (ed.), Coleopterorum Catalogus. W. Junk, Berlin, 65 pp.

Pic, M. 1927. Pars 94. Phengodidae, Karumiidae. IN: S. Schenkling (ed.), Coleopterorum Catalogus. W. Junk, Berlin, 8 pp.

Solervicens, J. 1991. Descripción de la hembre de Pleolobus fuscescens Philippi y Philippi (Coleoptera, Karumiidae) y observaciones sobre esta especie. Acta Entomologica Chilena, 16: 119–124.

General appearance. Total length 4.5–25 mm. Ratio of body length to greatest body width 1.85–4.21. Body slightly flattened to moderately convex, or strongly convex. Sides of body not evenly curved. Body not capable of conglobation (rolling into a ball). Upper surfaces of body glabrous or subglabrous, or clothed with distinct hairs, setae or scales. Vestiture of upper surfaces not including stiff, erect, dark bristles; not including scales or scale-like setae, or including scales or scale-like setae. Upper surfaces of body without deep foveae. Prothorax, metathorax and-or abdomen without extrusible glands. Underside of body without hydrofuge surface(s).

Head. Ratio of head length to its greatest width (excluding eyes) greater than 1. Head width just behind eyes not distinctly greater than prothoracic width. Head not or slightly declined; not entirely concealed from above by pronotum; without elongate rostrum; not abruptly constricted posteriorly. Temples absent or not closely adpressed to prothorax; absent. Transverse occipital ridge or carina absent. Occiput without stridulatory file. Longitudinal axis of head (from occipital foramen to mouth cavity) inclined at an angle of less than 45 degrees. Frontal region not to moderately, gradually declined. Occipital region without median longitudinal groove or line (endocarina). Frontal region without median groove or line (endocarina). Head without ocelli.

Compound eyes present. Eyes not or only slightly protuberant, or strongly protuberant. Vertical diameter of eye less than 2 times horizontal diameter. Eyes finely facetted; without interfacetal setae. Ommatidium of the exocone type. Eye entire. Anterior or mesal edge of eye not or only barely emarginate. Posterior edge of eye not or barely emarginate.

Antennal insertions exposed from above, or concealed from above; moderately to widely separated. Antennae not borne on raised tubercles. Antennal insertions flush with head capsule or raised, not in fossae. Subantennal groove or cavity on head absent or very weakly developed. Frontoclypeal suture absent or incomplete, or indistinctly impressed, or distinctly impressed; straight, slightly curved or angulate. Clypeus not laterally emarginate. Anterior edge of clypeus or clypeolabrum straight to convex. Mouth cavity anteriorly or anteroventrally oriented. Pregular area without laterally opening cavities. Head ventrally without paired subgenal ridges. Head without anteriorly-projecting genal processes. Gular sutures widely separated or absent. Corporotentorium broad, or narrow; without median process. Cervical sclerites present.

Antennae. Number of antennomeres 11. Antennae when posteriorly extended not reaching middle of prothorax, or reaching beyond middle of prothorax but not middle of elytra, or reaching beyond middle of elytra but not elytral apices. Antennae filiform, or serrate, or pectinate or bipectinate. Antennomeres 3, 4 or 5 to 10 without or with single rami (uniramose). Antennae at least partly pubescent or with obvious modifications. Antennal modifications beginning on antennomere 3 (rarely 2). First antennomere (scape) less than 3 times as long as 2nd (pedicel). Antenna not geniculate; without apical club.

Mouthparts. Labrum at least partly visible; free, membranous or separated by suture. Major portion of labrum strongly transverse, or slightly transverse or subquadrate. Apex of labrum strongly convex, narrowly rounded or acute, or slightly concave or emarginate, or deeply emarginate or bilobed. Labrum moderately to heavily sclerotized, except at base and-or apex. Mouthparts not forming a piercing or sucking tube. Mandibles present. Mandible short and broad, or moderately elongate. Mandibular apex moderately to strongly, gradually curved mesally, or strongly and abruptly curved mesally; unidentate, truncate or rounded; subacute, bidentate or multidentate. Dorsal part of mandible without tubercle; without setose cavity. Mandible moderately to strongly, more or less evenly sclerotized or pigmented; visible in lateral view. Incisor edge of mandible with single tooth, or with 2 or more teeth. Mandible without mola; without prostheca. Prostheca absent or without articulated, sclerotized process. Inner basal angle of mandible without pubescent process. Maxilla with distinct galea and lacinia. Maxillary lobe(s) not stylet-like. Apex of galea or maxillary lobe densely setose or spinose; without heavily sclerotized teeth or hooks. Lacinia without hook(s) or spine(s). Apical maxillary palpomere cylindrical to fusiform, or slightly expanded and truncate to subtriangular; at least as wide as or longer than preapical one. Maxillary palp without complex palp organ. Apical labial palpomere cylindrical to fusiform. Ligula shallowly to moderately emarginate, or deeply emarginate or bilobed, or indistinct or absent.

Prothorax. Ratio of pronotal length to greatest pronotal width 0.52–0.75. Prothorax widest at middle, or posteriorly. Sides of prothorax more or less straight, or moderately to strongly curved. Prothorax not laterally compressed to form cavities for legs. Sides of prothorax not or slightly explanate. Base of prothorax not or slightly narrower than elytral bases, or distinctly narrower than elytral bases. Greatest prothoracic width not or slightly narrower than greatest elytral width, or distinctly narrower than greatest elytral width. Lateral pronotal carinae complete, or incomplete; simple; visible for their entire lengths from above, or not visible for their entire length from above; without a raised margin, or with a raised margin or narrow bead. Lateral portion of prothorax without deep pit. Pronotum without anterolateral callosities. Anterior angles of pronotum absent or not produced forward; absent, right or rounded, not produced. Posterior angles of pronotum absent or broadly rounded, or obtuse or right, or moderately to strongly acute; not produced and acute. Posterior edge of pronotum more or less straight or evenly rounded, or distinctly sinuate or variously lobed; simple; not or vaguely margined. Discal carinae of pronotum absent. Pronotal disc without paired basal impressions. Pronotum without median longitudinal groove or line. Anterior edge of pronotum simple, without margin, or with narrow margin or bead. Hypomeron without pit.

Anterior portion of prosternum at midline shorter than prosternal process, or longer than prosternal process. Lateral portion of prosternum in front of coxae as long as mid length of procoxal cavity, or longer than mid length of procoxal cavity. Anterior edge of prosternum not produced anteriorly. Prosternum in front of coxae flat to moderately convex. Prosternum in front of coxae without paired lines or carinae. Anterior edge of prosternum without margin; without mesal excavation. Anterolateral or ventrolateral portions of prothorax without cavities or grooves. Prothoracic cavities absent. Prothoracic grooves absent. Prosternal process complete, or incomplete, or absent; narrowed apically, or parallel-sided; flat, concave, or only slightly elevated or curved behind coxae, or strongly elevated and curved dorsally behind coxae; not extending to mesoventrite, or slightly overlapping mesoventrite. Apex of prosternal process acute or narrowly rounded. Prosternal process without transverse groove. Accessory (mesal) procoxal articulation absent. Ventral portion of prothorax on each side with notosternal suture only. Propleuron extending to anterior edge of prothorax, or not extending to anterior edge of prothorax. Propleuron or pleurotrochantin extending behind coxa, or not extending behind coxa. Procoxae not or slightly projecting below prosternum, or projecting well below prosternum. Procoxa without or with short concealed lateral extension. Procoxal cavities present, procoxae countersunk. Procoxal cavity strongly transverse. Procoxal cavities at middle contiguous, or narrowly separated. Procoxal cavities externally open; broadly open. Postcoxal projection absent or very short, or moderately long but not meeting prosternal process. Procoxal cavities without narrow lateral extensions. Procoxal cavities internally open. Prothoracic trochantin or pleurotrochantin at least partly exposed. Promesothoracic clicking mechanism absent.

Elytra. Elytra present. Ratio of elytral length to greatest elytral width 1.21–3.74. Ratio of elytral length to pronotal length 2–7.89. Elytra apunctate, irregularly punctate, or with 5 or fewer distinct puncture rows or striae, or with more than 5 distinct puncture rows; without scutellary striole. Number elytral puncture rows or striae 12 or more. Sutural stria absent or not deeply impressed near apex. Abdominal tergites exposed by elytra none or apex of 1, or 3 or more. Elytral apices meeting or almost meeting at the suture, or independently rounded or acute and separated by broad gap. Elytral suture not deflected near apex. Elytral apex without internal interlocking tongue. Epipleuron absent or incomplete, or complete; not or gradually narrowed. Lateral edge of elytron straight or weakly sinuate.

Pterothorax. Scutellum well developed; abruptly elevated; anteriorly simple; posteriorly broadly rounded or obtusely angulate, or truncate. Mesoscutum without stridulatory file. Mesoventrite without paired procoxal rests, or with paired procoxal rests. Paired mesoventral procoxal rests absent, horizontal or slightly oblique, or moderately to strongly oblique. Anterior edge of mesoventrite without prosternal rest. Mesoventrite not divided by longitudinal groove or discrimen, or at least partly divided by longitudinal groove or discrimen. Anterior edge of mesoventrite at midline on same plane as metaventrite. Mesoventral cavity absent, or small and shallow. Mesocoxa not conical and projecting, or conical and projecting. Mesocoxal cavities present, mesocoxae countersunk. Mesocoxal cavities at middle contiguous, or narrowly separated. Mesocoxae separated by less than shortest diameter of coxal cavity. Mesocoxal cavities circular to slightly transverse; not or slightly oblique. Mesoventrite separated by complete sutures from mesepisterna. Mesepisterna distinctly separated at midline; without deep pockets. Mesepimeron not visible from above. Mesocoxal cavities open laterally; not partly closed by metepisterna. Mesoventral process extending at least to middle of mesocoxal cavity. Mesometaventral junction absent or a point, or a complex fitting. Mesoventral and metaventral processes at midline separated by gap, groove, or suture. Accessory (mesal) mesocoxal articulation absent.

Metaventral discrimen or median line moderately to very long. Paired postcoxal lines of metaventrite absent. Postcoxal lines of metaventrite absent. Metaventrite longer than first abdominal ventrite. Postcoxal pits of metaventrite absent. Metaventrite moderately to strongly convex. Transverse groove of metaventrite present. Anterior edge of metaventrite without transverse carina between mesocoxal cavities. Exposed portion of metepisternum short and broad, or very long and narrow or absent. Metacoxae contiguous or narrowly separated; separated by less than longest coxal diameter; not extending laterally to meet elytra or sides of body, or extending laterally to meet elytra or sides of body; completely separated from metaventrite by suture. Metacoxal plates well developed, more or less uniform, or well developed mesally, weak laterally, or weakly developed, or absent; not concealing most of basal abdominal ventrite. Metacoxae not greatly enlarged; horizontally oriented, or obliquely oriented. Lateral arms of metendosternite short or absent. Metendosternal laminae absent. Ventrolateral processes of metendosternite absent or weakly developed, or strongly developed. Anterior process of metendosternite moderately long. Anterior tendons of metendosternite moderately or very close together. Apical portion of metendosternite not or only slightly emarginate.

Hind wing. Hind wing well developed; with normal transverse folds. Radial cell of hind wing well developed; shorter and broader. Inner posterior angle formed at base of radial cell right or obtuse. Radial cell not forming equilateral triangle. Ratio of length of apical area to total wing length less than 0.2, or greater than 0.5. Apical area of hind wing with one or more vague sclerotizations or pigment patches, or with one or more distinct veins (branches of RA and-or RP). Medial bar of hind wing not crossed by fold. Free veins in medial area of hind wing 5 or 6. Oblongum cell of hind wing absent. Medial fleck of hind wing absent; absent or not partly bisected by a vein. Wedge cell of hind wing well developed, or absent. Apex of wedge cell of hind wing acute. Anal lobe of hind wing absent. Posterior edge of hind wing without fringe of long hairs.

Legs. Femoral attachment of mid trochanter transverse or slightly oblique, or strongly oblique with base of femur separate from coxa. Mesotrochanter not reduced or concealed from below. Metafemur not much wider than mesofemur. Mesotibia not strongly widened, or strongly widened, widest at or near apex. Outer edge of mesotibia simple, crenulate or denticulate, or with distinct teeth or long spines. Outer subapical edge of mesotibia without antenna cleaner. Preapical surfaces of mesotibia without ridges or combs. Outer apical angle of mesotibia simple or slightly produced, without lobe, teeth or spines. Inner apical angle of mesotibia not or slightly produced, without tooth. Mesotibial spurs glabrous or absent, or serrate or pectinate; double. Mesotarsus with 5 distinct tarsomeres (pentamerous). Tarsomeres on hind leg at least as many as on mid leg. Tarsomeres on fore leg at least as many as on mid leg. Mesotarsomere 1 well developed and visible. Preapical mesotarsomeres together longer than apical one. Penultimate mesotarsomere not distinctly shorter than antepenultimate. Ventral mesotarsal lobes absent, or on more than one tarsomere. Mesotarsal claws paired; subequal in length and similar in form and angle of inclination; simple. Appendage on each tarsal claw absent. Mesotarsal claws without setae near base. Mesotarsal empodium absent or concealed; absent or with 2 or fewer setae. Outer edge of protibia simple and rounded to carinate but without lobes or teeth, except at apex. Outer apical angle of protibia simple or slightly produced, without lobe, teeth or spines, or with rounded lobe or process, sometimes bearing spines. Inner subapical edge of protibia without antenna cleaner. Protibial spurs double. Articulations of protibial spurs located in same plane. Hind legs without swimming hairs. Preapical surfaces of metatibia without ridges or combs. Metatibial articular area not to only moderately expanded, narrowly oval or oblique. Metatibial spurs double; subequal in length and form, or differing distinctly in length.

Abdomen. Number of abdominal ventrites 5–6. Number of basal ventrites connate none, or two. Abdominal sternite 2 visible, or apparently absent. First ventrite not completely divided by metacoxae. Suture between ventrites 1 and 2 distinct. Suture between ventrites 2 and 3 distinct. Ventrite 4 articulated with or connate with both 3 and 5. Postcoxal lines on ventrite 1 absent. Ventrite 1 not much longer than 2. Abdominal process acute or narrowly rounded, or absent. Ventrite 5 in female without circular depression. Posterior edge of ventrite 5 not crenulate. Last visible tergite and-or sternite (7 or 8) not forming terminal spine. Tergite and sternite 7 separated by membrane or distinct suture. Subapical abdominal luminous organ absent. Ventrites without setose patches or foveae. Functional spiracles on abdominal segment 8 present. Functional spiracles on abdominal segment 7 present. Functional spiracles on abdominal segment 6 present. Functional spiracles on abdominal segment 5 present. 7th abdominal spiracles located on sternite. 6th abdominal spiracles located in sternite. 5th abdominal spiracles located in sternite. Anterior edge of sternite 8 in male without median strut. Pygidium (sclerotized tergite 7 or 8) more or less horizontal. Anterior edge of sternite 9 in male without median strut. Tergite 9 in male deeply emarginate. Tergite 10 in male well developed and free.

Aedeagus trilobate; symmetrical. Anterior edge of tegmen or phallobase without struts. Parameres individually articulated to phallobase or base of penis; not outwardly hooked. Penis with dorsal and ventral lobes. Anterior edge of penis without struts, or with paired struts.

Illustrations. • Notodascillus. Notodascillus sublineatus Carter. Locality: Australia. Artist: F. Nanninga. Copyright CSIRO. Reference: Britton 1970. • Coptocera. Coptocera sp. Locality: Taiwan. Artist: S. P. Kim. Copyright CSIRO. • Escalerina. Escalerina microcephala (Escalera). Locality: Iran. Artist: L. M. Planet. Reference: Bolivar y Peltain 1926. • Genecerus. Genecerus nebulosus Gahan. Locality: East Africa. Photo: K. Smith. Copyright CSIRO.


The interactive key provides access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting specified attributes, and summaries of attributes within groups of taxa.

Cite this publication as: ‘Lawrence, J.F., Hastings, A.M., Dallwitz, M.J., Paine, T.A., and Zurcher, E.J. 2000 onwards. Elateriformia (Coleoptera): descriptions, illustrations, identification, and information retrieval for families and subfamilies. Version: 9th October 2005. http://delta-intkey.com’.

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