Beetles of the World
This is not a complete glossary of terms used in beetle morphology, but is it is meant to include all terms used in the characters and character notes, and some others that may be of general use. Terms referring to the ovipositor, internal female tract or soft anatomy are not included, since characters based on these have not been used. For more complete glossaries or discussions of particular character suites, See Baehr (b79), Beutel and Haas (1999), Campau (1940), Crowson (1981, 1984), Hlavac (1972, 1975), D’Hotman and Scholtz (1990), Jeannel and Paulian (1944), Kéler (1956), Kukalová-Peck and Lawrence (1993), Lindroth (1957), Matsuda (1965, 1970, 1976, ), Nichols and Schuh (1989), Séguy (1967), Tuxen (1970), Weber (1933, 1954) and other references cited below in the General Bibliography.
Abdominal process (intercoxal process of abdomen). Projection on ventrite 1 which extends anteriorly between metacoxae.
Abdominal sternite. Ventral sclerite of an abdominal segment (includes concealed as well as externally visible ones). Sternite number corresponds to that of true abdominal segment.
Abdominal ventrite. Visible ventral abdominal sclerite. Ventrite number does not correspond to true sternite number except in rare cases where sternite 1 is visible. Also called ventrite.
Accessory lobes (of apicale of tegmen). Paired articulated lobes arising from the apicale. Referred to by Spilman (1952) as lateral lobes, but the latter term usually synonymous with parameres.
Accessory mesocoxal articulation. A ball and socket joint formed mesally between the mesocoxa and mesoternal or metasternal process. It may consist of a lateral process at the apex of either process and a coxal impression or, occasionally, a mesocoxal knob and mesosternal impression.
Accessory procoxal articulation. A ball and socket joint formed mesally between the procoxa and prosternal process. It may consist of a prosternal knob and coxal impression or, occasionally, a coxal knob and prosternal impression.
Acone eye. Eye in which ommatidia lack both crystalline cone and corneal exocone lenses.
Adephagan aedeagus. Aedeagus which lacks a phallobase, so that parameres are articulated directly with the base of the penis and sometimes to each other. This type occurs in the suborders Archostemata, Myxophaga and Adephaga.
Aedeagus. The external genital apparatus in Coleoptera. Including a phallobase, parameres (sometimes absent or fused together) and a penis containing an invaginated endophallus, but excluding the genital capsule.
Anal area (of hind wing). The area lying between the anal fold and the wing base.
Anal lobe (of hind wing). The lobe formed by a posterior incision near the wing base between veins AA and AP and often at the end of the anal fold; the anal area when it is delimited apically by an incision or emargination.
Anelytrous. Without a trace of elytra.
Antenna cleaner. A concavity lined with hairs and/or stout setae and located near the apex of the protibia or mesotibia. Occurs in taxa with more or less filiform antennae, and used to clean the antenna by sliding it over the hairs.
Antennal cavity (of prothorax). A prothoracic cavity for housing the whole antenna or a portion of the antenna (usually the club).
Antennal club. An enlarged portion of the antennal apex, consisting of a variable number of antennomeres (often 3). In an incrassate, antenna the antennomeres gradually enlarge towards to apex, but if there is an abrupt change in length or width at some point, then the antennomeres beyond this are considered to be part of the club.
Antennal fossa. Saucer-like concavity surrounding the antennal insertion.
Antennal groove. See Subantennal groove.
Antennal insertion. Point of attachment for the antennae, consisting of an opening in the head capsule, sometimes with a reinforced sclerotized ring.
Antennomere. Antennal segment; including scape, pedicel and flagellomeres.
Anterior angles (of pronotum). The fore corners of the pronotal disc. These may be rounded, angulate or produced forward, forming rounded or acute processes.
Anterior process (of metendosternite). An extension of the apical portion of the metendosternite which usually bears the anterior tendons.
Anterior tendons (of metendosternite). A pair of tendons borne on the anterior process or the lateral arms of the metendosternite.
Anterolateral callosity (of pronotum). More or less flattened or callus-like area at or very near the anterolateral corner of the pronotum, and often containing a gland opening.
Apical (apicad). An adjective (or adverb) denoting position near or movement toward the apex of a body part. The apex of the head or pronotum is at the anterior end while that of the abdomen or an elytron is at the posterior end; on the legs or antennae, apical and distal are synonymous.
Apical area (of hind wing). A rather vaguely defined area of the hind wing apical to the ends of the radial and medial bars and last r-m crossvein.
Apicale (of tegmen). The apical portion of the sheath-like, tenebrionoid tegmen which is divided transversely. This appears to be formed by the fusion of the two parameres. Also called apical piece or paramere.
Apical Piece. See Apicale.
Basal (basad). An adjective (or adverb) denoting position near or movement toward the base of a body part. The base of the head or pronotum is at the posterior end while that of the abdomen or an elytron is at the anterior end; on the legs or antennae, basal and proximal are synonymous.
Basale (of tegmen). The basal portion of a sheath-like tegmen which is divided transversely. This appears to be homologous to the phallobase. Also called basal piece.
Basal piece. See Basale and Phallobase.
Bead. A fine raised margin.
Bilobate aedeagus. Aedeagus in which the phallobase and parameres are well developed but the penis is membranous or sclerotized only at base, where there may be a pair of anterior struts. This type is characteristic of many Scarabaeoidea.
Biramose antenna. The presence of a single ramus on each antennomere.
Bostrichoid aedeagus. Aedeagus in which the phallobase broadly overlaps the parameres, and the latter are fused basally to each other and to the base of the penis; a secondary bridge may also unite the parameres. This type of aedeagus is found in most Bostrichoidea.
Brachelytrous. With shortened elytra.
Buprestoid aedeagus. Aedeagus in which the phallobase is more or less reduced and often fused to the parameres, which form a tube surrounding the penis; the entire structure is usually somewhat flattened. This type occurs only in Buprestidae.
Canthus (pl. Canthi). A sclerotized bar encroaching on the eye.
Capitate antenna. Antenna with a distinct, abrupt club.
Cervical sclerites. Paired sclerites lying in membrane between the posterior edge of the head and the anterior edge of the pronotum. In some groups, the sclerite on each side may be subdivided.
Chrysomeloid aedeagus. A modification of the cucujiform aedeagus in which the parameres are highly reduced or absent, the anterior tegminal strut often laterally compressed, and the upper portion of the ring sometimes reduced to membrane, so that the tegmen becomes fork-like. This type occurs in most derived groups of Chrysomelidae.
Clavate antenna. Antenna gradually thickened and club-like, but without an abrupt club.
Cleroid aedeagus. See Cucujiform aedeagus.
Clypeolabrum. Sclerite formed by the complete fusion of the clypeus and labrum, so that there is no suture present.
Clypeus. The area of the beetle head between the frontoclypeal suture and the labrum, or in the absence of a frontoclypeal suture, the area just behind the labrum and in front of the eyes. Also called the epistoma.
Collar. A broad and often convex margin at the anterior or posterior end of the prothorax, set off by a distinct transverse groove.
Comb. A dense series of heavily sclerotized spines forming a comb-like structure. Usually located at the tibial apex but occasionally elsewhere on the tibia on one or more tarsomeres.
Conglobation. A type of body compaction in which the head and prothorax are capable of folding against the hind body, forming a sphere.
Connate ventrites. Ventrites which are immovably united, so that they can not slide over one another as they can when joined by membrane. This may be used as a synonym with fused ventrites, but they are always separated by a groove or line, while fusion sometimes involves the disappearance of any joining line.
Corporotentorium. The transverse bridge which joins the paired arms of the tentorium near the posterior edge of the head. The tentorial arms may also be joined anteriorly by a meeting of the laminatentoria. The bridge is usually narrow, occasionally broad, and rarely bears a median process.
Coxal cavity. The countersunk housing into which the coxa fits. These housings differ on each of the thoracic segments and are discussed separately. See Procoxal cavity, Mesocoxal cavity, Metacoxal cavity.
Cucujiform aedeagus. Aedeagus in which the phallobase forms a sheath or ring around the penis and the parameres are often reduced in size, fused to the phallobase or completely absent. The combined phallobase and parameres, usually referred to as the tegmen, may be drawn out anteriorly to form a narrow strut. This type of aedeagus includes those known as cleroid, sheath or vaginate and cucujoid, ring or annulate; it is characteristic of most Lymexyloidea, Cleroidea and Cucujoidea, as well as basal members of Chrysomeloidea and Curculionoidea. In Curculionoidea, this type of aedeagus is called the orthocerous type, although that term also implies that the penis is comprised of a doral and ventral lobe.
Cucujoid aedeagus. See Cucujiform aedeagus.
Cupule. A very short and broad, distally concave and usually glabrous antennomere just before the antennal club. This usually forms part of a mechanism in aquatic beetles for obtaining an air bubble.
Cupuliform antennal club. An antennal club in which the distal one or two antennomeres are more or less enclosed within the preceding one.
Curculionoid aedeagus. A modification of the cucujiform aedeagus in which the ring is very narrow with a narrow anterior strut, the parmeres reduced and fused to the ring, and the ring sometimes partly membranous, so that it resembles a fork. This type occurs in most derived curculionoids, and when combined with an undivided penis, is called the gonatocerous type.
Disc (of pronotum). The area of the pronotum which is visible dorsally and usually delimited laterally by the two lateral carinae. Contrasted with the paired pronotal hypomera, which extend onto the ventral surface.
Discal carina (pl. Carinae) (of pronotum). One or more sublateral, paramedian or median, longitudinal carinae on the pronotal disc. Contrasted with the lateral carinae, which form the edges of the disc.
Discrimen (of meso- or metaventrite). Median longitudinal groove in the metaventrite and occasionally the mesoventrite, representing an area of invagination of the original sternum. Also called the discriminal line. Term usually applied to metaventral discrimen only.
Distal (distad). An adjective (or adverb) denoting position near or at or movement toward the free end of an appendage or that furthest from the body.
Dorsal (dorsad). An adjective (or adverb) denoting position near or movement toward the upper side of the body or a body part.
Dorsal lobe (of penis). The upper lobe a penis which is divided horizontally into dorsal and ventral lobes (as in Dascillidae, some Scirtidae and some Psephenidae). See Tectum.
Double tegmen. Tegmen which has three anterior struts, two on one side of the penis and one on the other (usually two dorsally and one ventrally).
Edge. The exact edge of a structure. Contrasted with the word margin, which implies a beaded edge or bordered edge.
Elytral epipleuron. See Epipleuron.
Elytral suture. The line formed when two elytra in folded or closed position meet along the midline.
Elytron (pl. Elytra). The fore wing in Coleoptera, which is more or less uniformly sclerotized and in resting position is longitudinally oriented, usually meeting the opposite elytron along the midline.
Empodium (of pretarsus). An articulated, sclerotized process, lying between the tarsal claws and bearing 2 or occasionally several setae. In a number of Coleoptera, the empodium is absent or reduced and not visible beyond the apical edge of the claw-bearing tarsomere.
Endophallus. The internal, extrusible portion of the penis, sometimes bearing spines, hooks or other sclerotized structures.
Epipleuron (pl. Epipleura) (of elytron). A lateral, infolded portion of the elytra, which is separated from the elytral disc by a distinct fold or carina and which usually fits against the lateral portions of the abdomen.
Epistoma. See Clypeus.
Epistomal suture. See Frontoclypeal suture.
Eucone eye. Eye in which each ommatidium bears a crystalline cone just beneath the corneal lens.
Exocone eye. Eye in which each ommatidium bears a cone-like, internal projection of the cornea, which thus forms a lens.
Eye facet. Individual parts of the external surface of the compound eye; often convex but sometimes more or less flattened.
Femur (pl. Femora). The third and usually the stoutest segment of the beetle leg, articulated proximally with trochanter (or if the latter is absent, then the coxa) and distally with the tibia.
Filiform antenna. Antenna in which most antennomeres are longer than wide and more or less equal in width, and so resemble a filament or thread. The related term setiform has been used for antennae (in fossil beetles) which are narrowed apically, but this condition apparently does not occur in modern forms.
Flabellate antenna. Antenna in which most antennomeres bear a long, narrow, flattened process.
Flagellum (of antenna). That portion of the antenna beyond the pedicel or antennomere 2.
Flange. A term sometimes used for a broad, projecting or convex margin; here used as a synonym of collar (when referring to the prothorax).
Frons. The area between the eyes and just behind the frontoclypeal suture. In Coleoptera it is not or only rarely separated from the vertex posteriorly.
Frontal region. Usually referring to the area between the anterior portions of the eyes and in front of the eyes, whether there is a frontoclypeal suture or not.
Frontoclypeal suture. A transverse groove separating the frons and clypeus and forming internally an epistomal ridge. Also called the epistoma.
Functional spiracle (of abdomen). Spiracle having a distinct opening and tracheal connection. Non-functional spiracles may be represented by a minute opening or scar and a blocked tracheal remnant. Primitively there are 8 functional abdominal spiracles, but 8 is lost in many taxa (including all Cucujiformia) and 7–8, 6–8 or 4–6 may be lost in some others.
Galea (pl. Galeae). The lateral or outer lobe of the maxilla.
Gena (pl. Genae). The ventrolateral part of the head below and behind the eye and laterad of the gular sutures.
Genal process. An anterior projection of the gena, sometimes visible from above beyond the mandibles.
Geniculate antenna. Elbowed antenna, or one in which the pedicel and flagellum of the antenna articulates with the scape at a distinct angle.
Genital capsule. A capsule more or less enclosing the aedeagus. This capsule normally consists of the combined 9th and 10th abdominal segments, but occasionally it may be formed by the 8th segment, in which case the pregenital segments are reduced to a fork-like spiculum gastrale. See Pregenital segments.
Glabrous. Without hairs. See Subglabrous.
Histeroid aedeagus. Aedeagus in which the phallobase and parameres form a tube surrounding the penis. This type is found only in Sphertididae, Synteliidae and Histeridae.
Hydrofuge surface. A portion of the body surface covered with dense hairs, which often have a complex structure. Under low magnifications, these areas have a characteristic dull sheen. Hydrofuge surfaces repel water and in some cases they form a plastron.
Hypomeron (pl. Hypomera) (of pronotum). That portion of the pronotum which is visible from the ventral side; when there is a lateral pronotal carina, this is the portion below that carina (the pronotal disc being above it). The postcoxal projection in Polyphaga is part of the hypomeron.
Incrassate antenna. An antenna in which the antennomeres gradually increase in width towards the apex or increase and subsequently decease in width. When the increase is marked, the antenna looks club-like and is often called clavate.
Intercoxal process (of abdomen). See Abdominal process
Intercoxal process (of prosternum). See Prosternal process
Interfacetal setae (of eye). Setae arising between adjacent eye facets.
Labium. The lower lip; a compound structure forming the floor of the mouth. In Coleoptera, it is usually unpaired but may have two glossae and almost always bears two palps. Composed of the basal mentum and apical prementum.
Labrum. The upper lip; a median sclerite, usually articulated to the clypeus, which forms the roof of the mouth.
Lacinia (pl. Laciniae) (of maxilla). The mesal or inner lobe of the maxilla.
Lamellate antennal club. Antennal club composed of broad, flattened, plate-like segments, which are capable of lying flat against one another.
Larviform. Having all the characteristics of a larva, except with respect to the genitalia or genital opening. All truly larviform adult beetles have simple (or no) eyes, less than 4 antennomeres, a single tarsomere and single pretarsal claw.
Lateral (laterad). An adjective (or adverb) denoting position near or movement toward the sides of the body.
Lateral arms (of metendosternite). Paired lateral projections of the metendosternite, often bearing laminae and anterior tendons.
Lateral lobes (of aedeagus). See Accessory lobes, Paramere.
Lateral pronotal carina (pl. Carinae). A sharp lateral edge on the prothorax separating the pronotal disc above and the hypomeron below.
Ligula. A median projection of the prementum; comprised of the fused glossae.
Luminous organ. A light-producing organ usually located just beneath the surface of one or more apical or preapical ventrites, but occasionally elsewhere.
Mandible. One of the paired lateral biting jaws in beetles, lying just below the labrum and just above the maxillae. The mandible is usually relatively stout and heavily sclerotized, with one or more apical teeth, a basal mola or grinding area, a membranous prostheca distal to the mola and sometimes one or more accessory teeth.
Manubrium. A narrow strut attached to the anterior end of the tegmen.
Margin. An edge which is raised forming a narrow to moderately broad bead, lip, flange or collar.
Maxilla (pl. Maxillae). One of the paired, lateral organs lying just below the mandibles and just above the labium in beetles. The maxilla usually consists of a basal cardo, the stipes or main body, an outer and inner lobe (galea and lacinia, respectively) and a maxillary palp.
Maxillary lobe. One of the two apical lobes of the maxilla (galea or lacinia).
Medial. See Mesal. May also refer to the medial vein or medial area of the hind wing.
Medial area. That portion of the hind wing behind the medial bar (MP1+2) and the anal fold. Also called medial field (Kukalová-Peck and Lawrence 1993).
Medial fleck (of hind wing). A portion of the wing membrane bearing rasp-like structures and lying somewhere near the apex of the vein MP3. Also called the subcubital fleck. This structure may act as a holdfast when contacting a similar patch on the opposing wing or the underside of the elytron. Also known as a katastigma.
Median. On the midline.
Median area (of hind wing). That area of the hind wing between the median bar (MP1+2) and the anal fold (between AA and AP).
Median bar (of hind wing). The posterior of the two major supporting structures of the hind wing in beetles, formed from the vein MP1+2 and in most Archostemata, Myxophaga and Adephaga supporting the oblongum cell at or near its apex. In most Polyphaga its apex is joined to RP, forming the radio-medial loop.
Median lobe. See Penis.
Mesal (mesad). An adjective (or adverb) denoting position near or movement toward the midline of the body.
Mesepimeron (pl. Mesepimera). The posterior part of the mesothoracic pleuron, the exposed portion of which is joined to the metaventrite and metepisternum and forms part of the mesocoxal articulation; another concealed portion lies beneath the elytra and extends anterodorsally to form part of the elytral articulation.
Mesepisternum (pl. Mesepisterna). The anterior part of the mesothoracic pleuron, the exposed portion of which is joined mesally to (or sometimes fused with) the lateral edge of the mesoventrite and forms part of the mesocoxal articulation; another concealed portion lies beneath the elytron and extends anterodorsally to form part of the elytral articulation.
Mesial. See Mesal.
Meso-. Prefix referring to a structure forming part of the mesothorax, including mid legs (e.g. mesocoxa, mesepisternum, mesotarsus, mesepisternum).
Mesocoxal cavity. The countersunk sclerotized cavity for housing the mesocoxa; formed from the mesoventrite and metaventrite, usually with the addition of one or more elements of the mesopleuron (or more rarely the metapleuron). The cavity or housing is almost completely sclerotized (except where the coxa is joined by membrane). In some cases, there is no real cavity or housing present, and the coxa is attached externally by a broad membrane.
Mesofemur. The femur of the mid leg.
Mesometaventral junction. The meeting of the mesoventral and metaventral processes; this may consist of a simple meeting of the two processes, but in some cases a complex ball and socket joint is formed and in others the two processes are connate or completely fused.
Mesoscutum. The anterior part of the mesonotum in beetles, occasionally bearing a stridulatory plate.
Mesosternal cavity. See Mesoventral cavity.
Mesosternum. See Mesoventrite.
Mesotarsal. Referring to the tarsus (and pretarsus) of the mid leg.
Mesothorax. The second (middle) segment of the beetle thorax.
Mesoventral cavity. A mesal cuticular cavity on the mesoventrite, which houses the apex of the prosternal process.
Mesoventral process. A posterior projection of the mesoventrite which may meet an anterior projection of the metaventrite.
Mesoventrite. The major ventral sclerite of the mesothorax. This consists mainly of combined precoxal elements (preepisternites) fused together or separated by a discrimen. This structure is usually called the mesosternum, but the true sternum is no longer visible externally (Campau 1940, Ferris 1940, Lawrence 1999, Beutel and Haas 1999).
Meta-. Prefix referring to a structure forming part of the metathorax, including hind legs (e.g. metacoxa, metepimeron, metatibia, metaventrite).
Metacoxal cavity. The countersunk sclerotized cavity for housing the metacoxa; formed mainly by the base of the abdomen.
Metacoxal plate. A partial or complete, flattened, ventral projection of the metacoxa, which forms an excavated area for housing the metafemur.
Metasternum. See metaventrite.
Metathorax. The third (posterior) segment of the beetle thorax.
Metaventral process. An anterior projection of the metaventrite which usually meets a posterior projection of the mesoventrite.
Metaventrite. The major ventral sclerite of the metathorax. This consists mainly of combined precoxal elements (preepisternites) and paired metakatepisterna fused together or separated by a discrimen. This structure is usually called the metasternum, but the true sternum is no longer visible externally (Campau 1940, Ferris 1940, Lawrence 1999, Beutel and Haas 1999).
Metendosternal laminae. Flattened processes located on the lateral arms of the metendosternite.
Metendosternite. A ventral, median, internal invagination of the metathorax forming a complex, fork-like structure to which muscles are attached; a remnant of the original sternum.
Metepimeron (pl. metepimera). The posterior part of the metathoracic pleuron, the exposed portion of which, if present, is relatively small, lying between the lateral edge of the transversely oriented metacoxa and the elytron and forming the main coxal articulation; another concealed portion extends anteriorly and forms part of the hind wing articulation.
Metepisternum (pl. metepisterna). The anterior part of the metathoracic pleuron, the exposed portion of which is more or less longitudinally oriented, lying on each side of the metaventrite; another concealed portion lies beneath the elytron and extends anterodorsally to form part of the notal wing process. This structure is actually the anepisternum; the katepisternum forms the posterior end of the metaventrite.
Moniliform antenna. Antenna in which the antennomeres are about as long as wide and more or less bead-like.
Mouth cavity. The area enclosed by the labrum-epipharynx, mandibles, maxillae and labium-hypopharynx.
Mucro. A non-articulated projection arising from the inner apex of the tibia.
Notopleural suture. Suture separating the external propleuron from the pronotum; occurring in most Archostemata, Adephaga and Myxophaga.
Notosternal suture. Suture separating the prosternum from the pronotum.
Oblongum cell (of hind wing). A cell located at the end of the medial bar and formed from rp-mp crossveins; occurs in most Archostemata, Adephaga and Myxophaga.
Occipital carina. A transverse carina in the occipital region, usually located at the point where the top of the head normally protrudes from the anterior edge of the pronotum.
Ocipital line. Median longitudinal line or ridge on the posterior part of the head, extending from the occipital foramen to some point on the vertex or frontal region; usually associated with an endocarina. See occipital groove.
Occipital region. The posteriormost area of the head capsule; not clearly distinguished from the vertex, which lies just in front of it.
Occipital groove. Median longitudinal groove on the posterior part of the head, extending from the occipital foramen to some point on the vertex or frontal region; usually associated with an endocarina. See occipital line.
Ocellus (pl. Ocelli). A simple eye located between or behind the compound eyes; there may be a single, median ocellus or a pair of them.
Ommatidium (pl. Ommatidia). An element making up the compound eye and visible externally as an eye facet; consisting of an external cornea (sometimes projecting internally as a corneal exocone lens), a crystalline cone (in eucone eyes only), a clear zone and a rhabdome (Caveney 1986).
Palpomere. Palp segment.
Paramere. One of a pair of processes usually articulated to the phallobase of the beetle aedeagus. Also referred to as lateral lobes. Occasionally used in the singular for the apicale (Spilman 1952).
Pectinate antenna. Anntenna in which most antennomeres bear short, flattened processes and so appear comb-like.
Pedon. The lower lobe of a penis which is divided horizontally into dorsal and ventral lobes; usually referring only to the penis in Curculionoidea.
Penis. The main intromittent organ in beetles, usually consisting of an external, sclerotized tube and an internal, inflatable endophallus; also refers to the external tube only.
Perfoliate antenna. Antenna in which most antennomeres are flattened and expanded on each side of the articulation.
Phallobase. The basal lobe of the aedeagus in beetles; often enlarged or combined with the fused parameres to form a tegmen.
Pleural membrane (of abdomen). The membrane joining abdominal tergites to sternites.
Pleurosternal suture (of prothorax). Suture joining the propleuron to the prosternum in Archostemata, Adephaga and Myxophaga.
Pleurotrochantin (of prothorax). The combined propleuron and protrochantin occurring in Myxophaga and Polyphaga. The distal portion is usually called the trochantin, although the dividing line between this and the pleuron is rarely discernible.
Plumose antenna. Antenna in which most antennomeres bear single or paired, narrow or cylindrical processes usually bearing fine hairs.
Postcoxal line (of abdomen). Raised line or carina arising from the hind edge of the metacoxal cavity and extending posteriorly or posterolaterally and sometimes recurved; rarely there may be more than one line on each side.
Postcoxal line (of metaventrite). Raised line or carina arising from the hind edge of the mesocoxal cavity and extending posteriorly or posterolaterally and sometimes recurved. Rarely there may be more than one line on each side.
Postcoxal projection (of hypomeron or prothoracic pleuron). A mesal projection of the hypomeron or prothoracic pleuron, which extends behind the procoxa and may meet the prosternal process or, in some cases, the opposing postcoxal projection.
Posterior angles (of pronotum). The hind corners of the pronotal disc. These may be rounded, angulate or produced backwards forming acute processes.
Pregenital segments. Terminal abdominal segments to which the aedeagus is attached by connecting membrane; consisting of the 9th and 10th abdominal segments (the last often highly reduced and not distinguishable). See Genital capsule.
Pregular area. The area in front of the gular sutures (and posterior tentorial pits) and behind the attachments of the mouthparts.
Pretarsal claw. See Tarsal claw.
Pretarsus (pl. Pretarsi). The terminal leg segment; usually consisting of paired claws and a median empodium.
Pro-. Prefix referring to a structure forming part of the prothorax, including fore legs (e.g. procoxa, prosternum, protrochantin, protarsus).
Procoxal cavity. The countersunk sclerotized cavity for housing the procoxa; formed from the prosternum and sometimes the propleuron (Archostemata, Adephaga, Myxophaga) or hypomeron (Polyphaga); The cavity or housing may be almost completely sclerotized (except where the coxa is joined by membrane), but in most cases it consists of a small sternal shelf, sometimes joined to the pleuron or notum by a slender bar. In some cases, there is no real cavity or housing present, and the coxa is attached externally by a broad membrane.
Procoxal rest (of mesoventrite). One of a pair of concavities on the anterior edge of the mesoventrite which houses one of the procoxae at rest. Sometimes the procoxal rests continue onto the anterior edge of the mesepisterna.
Promesothoracic clicking mechanism. A complex jumping mechanism involving a long prosternal process, deep mesoventral cavity and anterior procoxal rest (on the mesoventrite), which occurs in most members of the beetle families Cerophytidae, Eucnemidae, Throscidae and Elateridae (Evans 1972, 1973).
Pronotal disc. That portion of the prothorax which is visible from above, or that lying above the lateral pronotal carinae when these are present.
Pronotal hypomeron. See Hypomeron.
Pronotum. The notum of the prothorax, including the pronotal disc and paired hypomera.
Propleuron (pl. Pleura). The pleuron or lateral wall of the prothorax. In Myxophaga and Polyphaga, the propleuron is more or less reduced and fused to the trochantin, and in the latter group it is not or only slightly visible externally. See Pleurotrochantin, Trochantin.
Prosternal process. The posteriorly-projecting, intercoxal process of the prothoracic sternum; the process may be absent or very short, so that the coxal cavities are confluent, or it may extend behind the procoxae and overlap the mesoventrite (in rare cases reaching the metaventrite).
Prosternum (pl. Prosterna). The major ventral sclerite of the prothorax, joined laterally either to the paired propleura (Archostemata, Adephaga, Myxophaga) or paired hypomera (Polyphaga).
Prostheca (pl. Prosthecae). A membranous (or rarely partly sclerotized), usually setose, structure lying distal to the mola.
Prothoracic cavities. Paired, broad cavities on the ventrolateral, dorsolateral or anterolateral portions of the prothorax and housing the antennas, antennal clubs, or fore legs.
Prothoracic grooves. Paired, narrow grooves, usually on the ventrolateral portions of the prothorax and housing the antennae and/or fore legs.
Prothorax. The first (anterior) segment of the beetle thorax; usually relatively large and always separated from the meso- and metathorax and independently movable.
Proximal (proximad). An adjective (or adverb) denoting position near or at or movement toward the end of an appendage nearest the body.
Pygidium. The terminal exposed and sclerotized tergite; this may be tergite 7 or 8.
Radial bar (of hind wing). The anterior of the two major supporting structures of the hind wing in beetles, formed from the veins Sc and RA and in many Polyphaga supporting the Radial cell at or near its apex.
Radial cell (of hind wing). In polyphagous beetles a cell formed by the diverging and subsquent converging of veins RA1+2 and RA3+4. May also be applied to a series of cells formed mainly by radial crossveins in Archostemata, Adephaga and Myxophaga.
Ramus (pl. Rami). A projection on an antennomere. See Uniramose, Biramose.
Scutellary striole. A shortened stria or puncture row lying just laterad of the scutellum but not extending very far posteriorly.
Scutellum. The posterior portion of the mesoscutum, which in beetles usually fits in between the bases of the elytra and may be part of an elytral locking mechanism (Gorb 1998, 1999).
Serrate antenna. Antenna in which most antennomeres project slightly in one direction forming a more or less acute process, giving the antenna has a saw-like appearance.
Spiculum gastrale. Narrow strut attached to the anterior end of sternite 9 and serving as a muscle attachment.
Staphylinoid aedeagus. Aedeagus in which the parameres and penis are well developed but the phallobase is reduced to a narrow strip of cuticle or membrane only; in the latter case the parameres appear to be joined directly to the penis and the aedeagus resembles the adephagan type.
Stria. A fine, longitudinal impressed line on the elytra, often containing punctures.
Stridulatory file (of mesoscutum). A shiny area on the mesoscutum of Megalopodidae, Disteniidae, Vesperidae, many Cerambycidae and some Nemonychidae which contains many very fine transverse ridges (visible only under very high magnifications) and acts with a plectrum on the hind edge of the pronotum to produce a sound.
Strut. A rod-like structure to which muscles are attached.
Subantennal groove. Groove or concavity usually lying below the antennal insertion and sometimes extending posteriorly along the ventral portion of the head.
Subcubital fleck. See Medial fleck.
Subglabrous. Bearing very short and fine and/or scattered setae only, and so appearing glabrous under lower magnifications.
Subgenal ridges. A pair of sharp longitudinal ridges extending from the maxillary articulations to the posterior region of the head and usually forming the lateral edges of a concavity. The subgenal ridges usually occur in conjunction with a strongly declined head and fit against the procoxae when the head is at rest.
Sutural stria. The elytral stria closest to the suture.
Suture. A joint or impressed line. Traditionally indicating the meeting of two major body segments, but often used also for an invagination of an internal endocarina or apodeme. See Elytral suture.
Swimming hairs. Relatively long and dense hairs located on the mid and hind legs of some aquatic beetles which aid in swimming.
Tarsomere. One of the elements of the tarsus.
Tarsal. Relating to the tarsus.
Tarsal claw. Usually one of two articulated, sclerotized, claw-like processes attached to the apex of the tarsus. These claws and the empodium comprise the pretarsus. Occasionally, there is a single claw or none at all.
Tarsomere. One of the divisions of the tarsus.
Tarsus (pl. Tarsi). The fifth segment of the beetle leg, which is articulated proximally with the tibia and distally with the pretarsus; almost always subdivided into two to five tarsomeres.
Tectum. The upper lobe of a penis which is horizontally divided into dorsal and ventral lobes; usually referring only to the penis in Curculionoidea.
Temple. The lateral portion of the head between the posterior edge of the eye and an abrupt narrowing of the head to form a posterior neck.
Tenebrionoid aedeagus. Aedeagus in which the phallobase (or basale) and partly to completely fused parameres together form an incomplete sheath on one side (usually dorsal) of the penis; the parameres are not individually articulated but may form a combined apical piece (apicale), which is articulated to the phallobase. In some groups there are articulated, accessory lobes attached to the apicale, and these may be confused with parameres.
Tibia (pl. Tibiae). The fourth and often the longest segment of the beetle leg, articulated proximally with the femur and distally with the first tarsomere.
Tibial. Relating to the tibia.
Tibial articular area. The apical surface of the tibia to which the first tarsomere and tibial spurs are attached; sometimes greatly expanded on the hind leg.
Tibial spur. An articulated, multicellular, spur-like process located at the apex of the tibia; usually paired but occasionally single, and sometimes absent.
Transverse folds (of hind wing). Those more or less obliquely transverse folds which are involved in shortening the wing length.
Transverse groove of metaventrite. A groove partly or completely separating the anterior portion of the metaventrite (paired preepisternites) with the posterior portion (metakatepisternum). It is more or less complete in Archostemata but is usually more or less reduced to a short groove crossing the discrimen, or completely absent.
Trilobate aedeagus. An aedeagus consisting of a well developed phallobase, paired articulated parameres and a sclerotized penis. This type of aedeagus occurs in many primitive Polyphaga.
Trochanter. The second segment of the beetle leg, articulated proximally with the coxa and distally with the femur; usually a relatively small sclerite and occasionally highly reduced or absent.
Trochanteral. Relating to the trochanter.
Trochantin. A precoxal sclerite articulating with the coxa, sternum and pleuron or sometimes fused to the pleuron or apparently absent.
Trochantinal. Relating to the trochantin.
Uncus. A solid process arising from the outer edge of the tibial apex and either hooked, curving inwardly or sometimes extending across the apex and projecting inwardly.
Uniramose antenna. The presence of a single ramus on each antennomere.
Ventral (ventrad). An adjective (or adverb) denoting position near or movement toward the lower side of the body or a body part.
Ventral lobe (of penis). The lower lobe of a penis divided horizontally into dorsal and ventral lobes. See Pedon.
Ventrite. See Abdominal ventrite.
Ventrolateral process (of metendosternite). One of a pair of processes extending basally or posteriorly from the center of the metendosternite bear the bases of the lateral arms.
Vestiture. A general term applying to the body covering, including all forms of setae (e.g. hairs, scales etc.).
Wedge cell (of hind wing). A cell in the posterior portion of the wing formed by two posterior forks of CuA and an anterior fork of AA. It may also be referred to as the 2nd cubito-anal cell (the first being formed between the base of CuA and AA and the first posterior fork of CuA). This has been inappropriately called the “anal” cell, but it is formed mainly by elements of the cubitus.