Glossary of Weevil Characters

There is much disagreement in different publications as to the correct name to use for different characters and, indeed, just what those characters are. Miguel Alonso-Zarazaga raised this issue in the Forum; in fact it was one of the drivers to set up the site in the first place.The preliminary glossary below is a start at addressing these problems.

The intent is to enable users to discover the meaning of terms found in descriptions, and to select the appropriate term to use.  Terms in wider use are not included, and the user is directed to more general publications such as Torre-Bueno's Glossary of Entomology.This list cannot be more than indicative, but many of the characters are discussed more fully in other publications, and included in larger dictionaries.  See, for example, Davis (2009), Lyal (1995), Maggenti et al, (2008), Morimoto & Kojima (2003), Thompson (1992),Torre-Bueno (1989), Wanat (2001).

If you add references to the bibliography please could you include the key word 'morphology' to help others find them?

If citing this Glossary, an appropriate citation is Lyal, C.H.C. (Ed.) Glossary of Weevil Characters. International Weevil Community Website. (accessed xx/xx/xxxx).

Please comment and add to the contents, which will be revised regularly.


Accessory glands (female genitalia) – glands associated with the female genitalia, which in at least some cases contain symbiotic organisms. Probably not homologous throughout Curculionoidea, and appear in different forms and attached to different parts of the genitalia.  See Kuschel (1987).

Adelognatha (informal group of weevils) - a group of Curculionidae characterised by the adelognathous character state (q.v.), broadly equivalent to the Entiminae of Thompson (1992). They are thus also characterised by a short, broad rostrum, the deciduous mandibular process present, larval antennae lacking a projecting apical part; larvae living free in soil. Some Entiminae have phanerognathous mouthparts, however (q.v.). The group has no formal status.  See also ‘Phanerognatha’.

Adelognathous (head, mouthparts) – refers to the maxillae being concealed by the prementum.  Thompson (1992) notes that in some cases the stipites are visible at the posterior angles of the prementum, and that in fact the degree to which the maxillae are concealed by the prementum is very variable. The contrasting term is ‘Phanerognathous’ (q.v.)

Adelphic – female mating with more than one male – not limited to weevils.

Aedeagus (male genitalia) – Combined structure comprising the tegmen and penis. See also 'pedal' and 'pedotectal' as types of aedeagus.

Airtube (larva) – respiratory appendage (May, 1994)

Annulated – segmented; in rings – sometimes used of antennal club.

Anapleural suture (metathorax) – see metanepisternal suture (preferred term).

Anepisternum (=episternum) (thorax) - anterior sclerite of the peluron, discernable on the mesothorax and metathorax in weevils (mesanepisternum, metanepisternum) (definition changed May 2012)

Anophthalmic (head) – lacking eyes.

Antenna (head) - sensory appendage on either side of the rostrum, comprising 11 articles: scape, 7-segmented funicle and 3-segmented club) (see under ‘Antennal segment’ for discussion of terminology of the antennal ‘segments’). Although sometimes referred to as 12-segmented, this depends on the interpretation of the club components (q.v.) and is apparently a misapprehension. (see states: geniculate antenna, subgeniculate antenna) See also Antennal segment, desmomere, antennomere. (definition changed 1/06/2012)

Antennal article (head) – see Antennal segment (preferred term). (definition changed 23/11/2011)

Antennal club (head) - see under Club.

Antennal insertion (head) – point of attachment of the antenna.  Antennal insertions are considered to be exposed when at least some portion of each antennal socket is visible from above the long axis of the rostrum. (After Lawrence, Beutel, Leschen & Slipinski, 2010).

Antennal segment (antennal article, antennomere, desmomere (in part, joint) (head, antenna) – individual elements of the antenna.  The terms used suffer from a difference in meaning between morphological correctness and in practice. Morphologically the antenna, like other insect antennae, comprises three true ‘segments’: a scape, pedicel and flagellum. The flagellum may be secondarily subdivided into a number of antennomeres, which are not true segments (in terms of holding muscle insertions). However, the traditional division in weevils is into scape, funicle and club, the funicle comprising the pedicel and up to 6 antennomeres of the flagellum (rarely seven if an antennomere more usually part of the club is separate), and the club a further three flagellum antennomeres. The pedicel is sometimes referred to as the first antennomere or first segment of the funicle. The terms pedicel and flagellum are not used in weevil taxonomy. This provides confusion over terminology, with the different articles being termed segments, antennomeres, desmomeres, joints etc.  The elements of the club are rarely termed antennomeres but the term ‘clubomere’ has been used (not recommended here).  The term ‘segment’ is adopted here for all articles, recognizing the morphological inappropriateness of this. (definition changed 1/06/2012).

Antennomere (head, antenna) – see Antennal segment (preferred term).The issues surrounding the use of this and other terms for the structure are discussed under ‘Antennal segment’ above. (definition changed 01/06/2012).

Anterior tentorial pit (head) – the invagination of the head capsule corresponding to the position of the anterior arms of the tentorium inside the head.  The Anterior Tentorial Pits lie at the anterior end of the subgenal sulcus in weevils, near the mandibular articulation (Lyal, 1995).

Apical membranous lobe (male genitalia) – unsclerotised posteriorly-directed extensions of parameroid lobes on tegmen (Wanat, 2007).

Apical setal comb (=distal comb, tibial comb, setose fringe) (leg, tibia) – row of strong setae around the apex of the tibia and projecting distad. There is often a gap dorsally between the comb on the posterior and anterior faces, to allow the tarsus to be reflexed. The anterior comb may extend along the dorsal face of the tibia (e.g. some Molytinae), in which case it is termed 'ascending'.  (Thompson, 1992).  See also ‘secondary comb’, ‘corbel’.

Apodeme - chitinous ingrown of the exoskeleton to which muscles are attached; rod-like projection from any of several structures (e.g. penis, tegmen).

Apodemes of penis (=temones, aedeagal apodemes, median lobe apodemes) (male genitalia) – a pair of apodemes extending anteriorly from the base of the penis.  Elsewhere the term ‘temones’ is appied to tegminal apodemes.

Apodeme of tegmen (=manubrium, tegminal strut) (male genitalia) – Apodeme extending anteriad from base of tegminal ring ventrally.  See Manubrium. (amended June 2012)

Appendiculate claw (leg, tarsus) see "Tarsal Claw".

Apterous – lacking wings

Baculum (pl – baculi) (female genitalia) – Sclerotised bars or struts which serve to support a membranous ovipositor.

Basal piece (male genitalia) – see Manubrium.

Basal pocket (elytra, submarginal fold) - the region of the sublarginal fold that diverges away from the outer wall of the elytra to form a more or less deep pocket to accommodate the pleurite of the basal ventrites and the metathoracic lateral sclerites. See also 'Submarginal fold'.

Basal sclerites (male genitalia) – paired (usually) sclerites lying near the junction of the endophallus with the ductus ejaculatorius. Of variable form.

Basisternum (thorax) - the anterior part of each sternum, meeting the sternellum posteriorly.  Sometimes used incorrectly for the sternellum (q.v.) on the prothorax, but can be distinguished from this because the sternellum lies between and behind the coxae, whilst the basisternum is before the fore coxae.

Beak see rostrum (preferred term).

Bifid claw (leg, tarsus) see "Tarsal Claw"

Buccal cavity (head, mouthparts) – mouth cavity

Bursa (=bursa copulatorix; vaginal bursa) (female genitalia) – large closed membranous lobe of female genitalia branching from vagina generally at same point as common oviduct and spermathecal duct. (amended June 2012)

Cap-piece (male genitalia) – see Parameroid plate.

Cardo (head, mouthparts) – basal piece of the maxilla

Cervical sclerites (= postgula) (head) - small trapezoidal triangular sclerite or pair of sclerites at the posterior end of the gular suture(s) (Lyal, 1995).

Claw (leg, tarsus) - see 'Tarsal claw" (preferred term).

Club (= Antennal club) (head, antenna) - the apical antennal segments. The club generally has three segments (see under ‘Antennal segment’ for discussion of terminology of the antennal ‘segments’), either separate as in some basal groups or combined as in most Curculionoidea. In many weevils there appear to be 4 club segments, each delimited by a suture and each bearing a ring of elongate setae. However, the form of the groove between the apical 'segment' and the others differs from that between the true antennomeres (Wanat, 2001). The apparent 4-segmented club has been termed 'pseudotetramerous' by Wanat, 2001. The elements may be termed ‘club segments’, ‘club antennomeres’ or ‘antennomeres of the club’, the first of these being least clumsy (although inaccurate); the term ‘clubomere’ has also been used but is linguistically dubious. Key character states: loose: articulation between segments and segment 'neck' visible; compact: articulation and basal constrictions not seen, but borders between segments clearly visible; connate: borders or sutures between segments partly or completely lost. (Wanat, 2001) (definition changed 1/06/2012)

Clubomeres (head, antennal club) – the antennomeres that make up the club of the antenna. – see Antennal segment (preferred term). (definition changed 23/11/2011)

Collum (female genitalia, spermatheca) – the basal rounded part of the spermatheca.

Complex apparatus (male genitalia, endophallus) – see transfer apparatus.

Connate - of two segments or other articulating parts of the body. Not freely moving against one another.  There may or may not be a line between them marking the original suture. (amended June 2012)

Corbel (= Körbichen, corbulae) (leg, tibial apex) – area at apex of tibia defined by setal combs and tibial ridges. Open corbel: apex of tibia with apical setal comb (anterior and posterior) but no secondary comb and no inner flange. Enclosed corbel: tibial apex with secondary comb that joins apical comb to enclose a lenticular area that may be flat or convex, smooth and bare, squamose or setose; generally only on hind tibia. Semi-enclosed corbel: tibial apex with apical inner flange raised distal to setal comb. (Thompson, 1992).  Thompson (1992) recommends the term ‘corbel’ be abandoned in favour of ‘outer bevel’ (q.v.) and ‘inner flange’ (q.v.). See discussion on the Forum pages on the Corbel.

Cornu (female genitalia, spermatheca) – the apical, generally curved, more or less acuminate part of the spermatheca.

Coxite (female genitalia) - see Gonocoxite (preferred term)

Coxite-stylus (= vaginal palp) (female genitalia) - term applied to the structure where the stylus and gonocoxite are believed to have fused. Coined by Howeden (1992) in discussion of eyeless weevils in the Nearctic and Neotropics.

Deciduous mandibular process (= pupal mandibles, mandibular appendages, deciduous pieces, false mandibles, provisional mandibles, Supplementzähne) (head, mandible) – horn- or blade-like processes on the mandibles of Entiminae and relatives that almost always fall off in early adult life, leaving a distinct scar. The deciduous process may sit on a pedicel, which is present after the process has fallen off.  (Extended discussion in Thompson, 1992)

Declivity (=elytral declivity) (eytra) – the posterior part of the elytra that slopes ventrad.

Desmomere (= antennomere, funicle segments, antennal segment) (antenna, funicle) – the pedicel and antennomeres that make up the funicle of the antenna (Alonso-Zarazaga, 1989) – see discussion under Antennal segment (preferred term). (definition changed 1/06/2012)

Disc (thorax, pronotum) – dorsal portion of the pronotum.

Discrimen (thorax, metathorax) - Median longitudinal depressed line sometimes present on the metaventrite, corresponding with a median ridge internally representing the invagination of the true metasternum. The ridge is usually connected with the metendosternite. May be visible on the mesoventrite also.

Dorsal Adventitious Tooth (leg, tibia) - tooth on apex of tibia dorsally in addition to uncus.

Dorsal Apical Projection (leg, tibia) - dorsal projection on hind tibia lying at the basal end of the apical setal comb when this is ascending. 

Dorsal plate (male genitalia) – see Parameroid plate.

Duct-lobe (= nodulus) (female genitalia, spermatheca) – the part of the spermatheca from which the spermathecal duct arises.  Sometimes extended into a lobe or a tube.

Ductus ejaculatorius (=ejaculatory duct) (male genitalia) – duct between the testes and endophallus.

Ejaculatory duct (male genitalia) – see Ductus ejaculatorius.

Elytral declivity see declivity.

Elytral stria (pl - Elytral striae) (= stria) (elytra) – longitudinal groove or row of punctures along elytra.  There are usually 10, with striae III and VIII often joining posteriorly.  The first stria is the one closest to the sutural margin of the elytron.

Elytral submarginal fold (=epipleural fold, inferolateral flange) (Elytra) – the projecting longitudinal ridge on the ventral surface of the elytra near the costal margin.  In the basal third it may be more or less strongly curved away from the elytron inner surface, this character having been used for the Barididae of Zherikhin & Egorov (1990).  The fold is likely to function in locking the elytron to the abdomen and metathorax, the fold width and depth basally being related to the size of the metepisternite.  Discussed by Davis (2009).

Elytral sutural flange (elytra) - flange on the sutural margin of each elytron ventral to the margin itself.  The flange on the right hand elytron fits in the groove between the dorsal surface of the left hand elytron and the flange below it.  The margin of the left-hand elytron is wider than that of the right-hand elytron in 'higher' weevils, but about the same in 'lower' weevils. In higher weevils the extension of the flange allows for elytral locking when closed.  In cases where the elytra are 'fused' the 'fusion' may be due to the flanges being curled around each other and thus immovable. 

Elytro-tergal stridulation system (elytra and abdomen) – the organ responsible for sound production in many higher weevils. It comprises a file – a closely-set patch of parallel ridges on the inner surface of the elytra near the apex or along the sutural margin, and a plectrum – usually a patch or row of tubercles or a single tubercle each side of the mid-line on abdominal tergite 7. The plectrum may be a ridge or pair of ridges in some taxa. In Ithyporina and some Cryptorhynchina the female has the file on tergite 7, derived from the wing-binding patch. The organization of the tubercles and the shape and position of the file can provide useful characters. (Lyal & King, 1996).

Emarginate – notched at the margin.  May be used to indicate a concave (in plan) part of a margin.

Endophallus (= internal sac) (male genitalia) – membranous sac lying within penis contiguous with ductus ejaculatorius and penis. Sometimes armed with a variety of sclerites (see Transfer apparatus). Everts during copulation.

Epimeron (thorax) – posterior sclerite of the pleuron discernable on the mesothorax and metathorax in weevils (mesepimeron, metepimeron)

Epipleural bridge (prothorax) – see Hypomeral lobe (preferred term)

Epipleural fold - see elytral submarginal fold (preferred term)

Epipleuron (thorax, elytra) – the inflexed portion of the elytron laterally when the elytra are closed (Torre-Bueno, 1989).

Episternum (thorax) – see Anepisternum (preferred term)

Epistome (=epistoma, clypeus) (head, mouth) – sclerite immediately posterior to the labrum; since the labrum is lost / fused to the clypeus in most adult weevils other than Nemonychidae and Anthribidae the epistome is often used to discuss the sclerite immediately above the buccal cavity without having to decide if it is clypeus or clypeus + labrum fused. It may be fairly clearly demarcated from the dorsal part of the rostrum lying posterior to it (part of the frons) by colour and a ridge or depression (epistomal ridge and epistomal suture respectively) or a transverse row of setae.  Laterally there may be a depression (termed the paraclypeal depression by Morimoto & Kojima, 2003), which often has a small tuft of setae (termed the paraclypeal setae by Morimoto & Kojima, 2003).

Eye-flaps see postocular lobes (preferred term).

False spiculum (= false strut) – see Spiculum relictum (preferred term)

Fenestrae (male genitalia) – unsclerotised area of the parameroid plate (q.v.) bounded by sclerites (see suprafenestral sclerite and subfenestral sclerite).  Homology across Curculionoidea is unlikely. (see Wanat, 2007).

Fifth tarsomere (= unguitractor) (leg, tarsus) - the distal tarsomere, bearing the tarsal claws.

File (= elytral file, elytral strigil, pars stridens, stridulatory rasp, stridulatory file) (elytra – elytro-tergal stridulation system) – patch of fine, parallel ridges on the internal surface of the elytra, generally near the apex, which form part of the elytro-tergal stridulation system.

First connecting membrane (male genitalia) - see Post-tegminal membrane

Flagellum (male genitalia) – long tubular sclerite sometimes present within the endophallus with the gonopore at its apex.  In some cases (more rarely) the flagellum is one or a pair of rods within the ejaculatory duct but outside the endophallus.  The two structures are not homologous.  See also ‘Transfer apparatus’.  See Wanat, 2007.

Forceps (male terminalia) – externally-visible processes from 8th sternite in the amycterine Phalidura (Thompson, 1992).

Frena (male genitalia, endophallus) – paired sclerites in endophallus, situated sub-basally when endophallus everted, comma-shaped or hook-shaped.  Kuschel (1995) suggested their presence is a plesiomorphic character state in Curculionoidea.  (Wanat, 2001, 2007).

Frons (head, head capsule) - area between the eyes

Funicle (head, antenna) - the middle part of the antenna, lying between the scape and the club, comprising the pedicel and up to 6 'desmomeres' (antennomeres) ('pedicel' and 'flagellum' are terms rarely if ever used in weevil taxonomy).

Furcasternum - see Sternellum (preferred term).

Gena (head) – the part of the head capsule on each side below the eye, bordered dorsally by the frontal suture, posteriorly by the occipital suture, ventrally by the subgenal suture. 

Geniculate antenna (=elbowed antenna) (head, antenna) - the state in higher weevils where the pedicel (basal segment of the funicle) inserts subapically on the scape, causing the funicle to be held at an angle to the scape. cf. subgeniculate antenna

Genital chamber (male genitalia) – see Genital pocket

Genital pocket (=genital chamber, genital sheath) (male genitalia) – membranous invagination between tergum VIII and sternum VIII and to which spiculum gastrale is attached. It includes both genital opening and rectum.

Genital sheath (male genitalia) – see Genital pocket

Genital spiculum (female genitalia) - see Spiculum ventrale

Genital tract (female genitalia) – the vagina and bursa.

Gland-lobe (= Ramus) (female genitalia, spermatheca) -

Glossa (head, mouthparts) – the median lobe of the labium

Gonatoceri (informal group term) – name applied to a grade of Curculionoidea with a geniculate antenna and male genitalia lacking a separate tectum (q.v.), broadly equivalent to the Curculionidae of Thompson (1992) which are characterised by this state.  See also Gonatocerous, Orthocerous, Orthoceri, Heteroceri.

Gonatocerous (antenna) – see geniculate (preferred term).  Term now also used to describe a group of weevils (see below) and as a ‘shorthand’ to describe typical character states (e.g. ‘gonatocerous genitalia’).

Gonatocerous (male genitalia) – see pedal genitalia (preferred term).  

Gonocoxite (=hemisternite, coxite) (female genitalia) – one of a pair of conical sclerites apically on ovipositor, associated with segment IX and between which the female vulva opens. See also 'coxite-stylus'.

Gula (head, head capsule) - the sclerite lying between the gular sutures, where these are separate (Lyal, 1995)

Gular suture (head, head capsule – rostrum) - suture or pair of sutures extending from the posterior margin of the head capsule to the poterior tentorial pit(s). The sutures are often fused to a single suture in weevils. (Lyal, 1995)

Head capsule (head, adult) – term to denote the head apart from the rostrum.  

Hemisternites (female genitalia) – see Gonocoxite (preferred term).

Hemisternite (male genitalia) – one of a pair of sclerites on sternum VIII

Heteroceri (informal group term) – name applied to a grade of Curculionoidea characterised by possession of geniculate antennae (q.v.) and orthocerous genitalia (q.v.).  Comprises Dryophthoridae, Erirhinidae, Nanophyidae, Brachyceridae.  See also Gonatoceri, Orthoceri.

Horn sheath (= sheath) (prothorax) – simple or bifurcate tube-like invagination between prothroacic horns of some Baridinae and Conderinae. (Davis, 2009)

Humeral callus (mesothorax, elytra) – projection on humerus; may be used as simply another term for humerus.

Humerus (= humeral angle) (mesothorax, elytra) – anterolateral angle of elytron, sometimes produced. Tends to be rounded in apterous species. If there is a projection some authors term this a 'humeral callus' or a 'humeral umbone' (for a knob-like projection).

Hypomeral lobe (= pleural process; postcoxal bridge; postcoxal process; epipleural bridge; hypomeron) (prothorax) - the sclerotised area behind the procoxae formed from pleural (hypomeral) projections, meeting in the midline and abutting anteriorly medially on the sternellum.

Hypomeron - see Hypomeral lobe (preferred term).

Hypostomal sinus (head) – The notch between the hypostoma (q.v.) and the labium, in which the mandibles can be seen.  (Morimoto & Kojima, 2003).

Hypostomal sulcus (head, rostrum) – part of subgenal sulcus posterior to the posterior mandibular articulation.

Inferolateral flange (elytra) - see elytral submarginal fold (preferred term)

Inner flange (leg, tibia) – anterior / distal margin of the tibial socket when raised into a carina or ridge.  It may be raised just by the tibial insertion or extend from dorsal to ventral margins of the tibia; it lacks setae.  Often it is associated with the uncus.  It can occur on all three tibiae.  (Thompson, 1992).  See discussion on the Forum pages on the Corbel.

Integument - exoskeleton, particularly outer covering of entire insect.

Intercoxal process (abdomen) – portion of ventrite 1 extending anteriad between hind coxae.

Intercoxal process (= intercoxal prosternal process) (prothorax) – posterior extension of prothoracic sternum (basisternum) between fore coxae, meeting the sternellum if coxae sufficiently separated.

Interocular pit (head) – abrupt depression on dorsum of head, between eyes.

Internal sac (male genitalia) – see endophallus (preferred term).

Interstices see Interstriae (preferred term).

Interstria (= interval, interstice) (elytra) – raised longitudinal strip on elytra between striae. The interstria nearest the sutural margin is interstria I (Lawrence & Britton, 1991). Some authors (e.g. Vanin & Reichardt, 1976) numbered the interstriae in a different way, for example the first being called the sutural interval, the second as interstice I, the third as interstice II, and so on (Vanin, 2008).

Introse - with teeth on the apical margin of the mandible and the mandibles not opening beyond the lateral margins of the rostrum.

Intervals see Interstriae (preferred term)

Joints of funicle see antennal segment.

Labral rods (larva, mouthparts)  see tormae (preferred term)

Latero-ventral sulci (head, rostrum) - (Wanat, 2001)

Lenticular – lens-shaped

Ligula (head, mouthparts) – the terminal lobe(s) of the labium, comprising the glossae and paraglossae.

Mandibles (head, mouthparts) - Extrose - with teeth on the external face, the mandibles rotating away from the midline and opening away from the midline of the rostrum and not meeting apically.  

Manubrium (=apodeme of tegmen, tegminal strut, basal piece) (male genitalia) – apodeme extending anteriad from base of tegmen ventrally.  Wanat (2007) refers to the ‘basal piece’ as comprising the apodeme and arms curving round the side of the aedeagus and meeting a dorsal plate, and an equivalent concept is used by Lawrence et al (2010). 

Median lobe – see Penis (peferred term)

Median Lobe Apodemes (male genitalia) – see Apodemes of penis (predferred term).

Median notch (male genitalia) – term applied to gap between parameroid lobes (Wanat, 2007)

Mentum (head) – middle plate of the labium, not visible as a separate plate in adult Curculionoidea.

Mesanepisternum (= Mesepisternum) (thorax, mesothorax) – anterior pleural sclerite of the mesothorax (definition changed June 2012).

Mesendosternite. A pair of internal apodemes formed by invaginations within the mesocoxal cavities, probably homologous with the furca.

Mesepimeron (thorax, mesothorax) - Posterior pleural sclerite of the mesothorax.

Mesepisternum (thorax, mesothorax) – see Mesanepisternum (preferred term)

Mesonotum (thorax, mesothorax) – the dorsal sclerite of the mesothorax.

Mesorostrum (head, rostrum) - the section of the rostrum widened above the antennal insertion. If the broadening is absent, the term refers to the level of the antennal insertion. (Wanat, 2001).

Mesosternal canal (= mesosternal channel) (mesothorax) – channel on the mesosternum to receive the rostrum when the head is rotated down and the rostrum lies along the ventral surface of the thorax. Found in some groups currently within the Cryptorhynchinae and Molytinae. (cf mesosternal receptacle)

Mesosternum see mesoventrite.

Mesothoracic receptacle (= mesothoracic cup; pectoral receptacle) (thorax, Mesosternum) – cup-shaped depression of the mesothorax that accepts the tip of the rostrum if this is bent between the front legs. It may be in the form of a full cup with lateral walls and a posterior wall, or with lateral walls only. Not homologous across Curculionoidea, although often used as an apomorphy for Cryptorhynchinae.

Mesoventrite (= Mesosternum) (thorax, mesothorax) - ventral sclerite lying in front of and between mesocoxal cavities, comprised of the fused preepisternum and basisternum (according to Wanat, 2001) or preepisterna and katepisterna (according to Lawrence et al, 2010). Generally referred to as the mesosternum in weevil taxonomic literature but the true mesosternum is invaginated.

Metanepisternal suture (= anapleural suture, metepisternal suture, metathoracic pleurosternal suture) - suture between metasternum and metepisternum. In cross-section metasternal part of suture is cup-shaped, holding the metepisternum and allowing it to flex during flight. In some higher weevils sclerolepidia are present along the suture, arising from the metasternum. The suture may be lost in flightless weevils. (Lyal et al., 2006). (term changed March 2012).

Metanepisternum (= metepisternum) (metathorax) – anterior pleural sclerite of the metathorax, lying laterad to the metaventrite and mesoventrad to the metepimeron. Often partially and sometimes completely hidden by elytra. (definition changed March 2012).

Metanotum (thorax, metathorax) – the dorsal sclerite of the metathorax.

Metarostrum (head, rostrum) - basal part of rostrum, from base to widening above antennal insertion (Wanat, 2001).

Metasternal canal (metathorax) - channel on the metasternum to receive the rostrum when the head is rotated down and the rostrum lies along the ventral surface of the thorax. Found in Aedemonini and Sophrorhinini.

Metasternum see metaventrite.

Metathoracic pleurosternal suture see metanepisternal suture.

Metaventrite (= metasternum) (thorax) - ventral sclerite lying behind and between mesocoxal cavities, comprised of the fused preepisterna and katepisterna (Lawrence et al, 2010).   Generally referred to as the mesosternum in weevil literature but the true mesosternum is invaginated along the midline (see Discrimen).

Metendosternite (metathorax) – internal sclerite of the metathorax. It usually consists of a median stalk, two short to long lateral ‘furcal arms’ and a ‘longitudinal flange’ anterior to and between the arms from which a pair of tendons arise. There are often phylogenetically-important characters associated with this.

Metepimeron (thorax) – Posterior pleural sclerite of the metathorax, positioned laterad of and above the metanepisternum and mostly or completely concealed by the elytra. It may be fused to the metanpisternum.

Metepisternal suture see Metanepisternal suture (preferred term).

Metepisternum see Metanepisternum (preferred term)

Mucro (pl - mucrones) (leg, tibia) – tooth-like process on the inner (ventral) apical angle of the tibia, but not linked to the inner flange (q.v.). Proposed by Thompson (1992) to be homologous with the uncus (q.v.) following fusion with the inner flange.  See also ‘pre-mucro’.  In many Apionidae and Nanophyidae it is present in males but not females. (amended December 2012)

Mycangium (pl - mycangia) – structures on the body used for the transport of symbiotic fungi. Found in a number of weevils, particularly Scolytinae, and have clearly evolved more than once.

Nodulus (female genitalia, spermatheca) – see Duct-lobe (preferred term).

Ocular lobe (prothorax) – see postocular lobe (preferred term).

Orthoceri (informal group term) – name applied to a grade of Curculionoidea with Orthocerous antennae (q.v.) and male genitalia of the plesiomorphic ‘orthocerous’ type (q.v.). These are the basal weevils on the generally-accepted cladograms. See also Heteroceri, Gonatoceri.

Orthocerous (antenna) – straight, lacking an ‘elbow’ between the scape and funicle. cf ‘geniculate antenna’.

Orthocerous genitalia (male genitalia) – see pedotectal genitalia (preferred term)

Ostiolar sclerites (male genitalia) – pair of sclerites on dorsal wall of aedeagus adjacent to ostium

Ostium (male genitalia) – opening of aedeagus through which the endophallus everts.

Outer bevel (leg, tibia) – The slope on the anterior face of the tibia between the anterior apical margin (as defined by the anterior apical setal comb) and the unmodified anterior face, delimited by a transverse swelling or ridge just basal to the tibial apex bearing with a secondary setal comb. Almost always on the hind tibia only (Entiminae, Brachycerinae). See discussion on the Corbel on the Forum pages.

Ovipositor (female genitalia) – the organ by which the eggs are laid, including gonocoxites, styli and vulva. (changed June 2012).

Paracoila (head, mouthparts) – pouch for receiving the cardo of the maxilla near the base of the hypostomal sinus (Morimoto & Kojima, 2003).

Parameres see parameroid lobes (preferred term).

Parameral lobes (male genitalia) – see parameroid lobes.

Parameroid lobes (= parameres, parameral lobes; see also parameroid plate) (male genitalia) - lobes attached to the posterodorsal part of the tegminal ring. May have posteriad unsclerotised extensions termed ‘apical membranous lobes’. The parameroid lobes are not unequivocally homologous with the parameres of other Coleoptera, hence the difference in terminology.

Parameroid plate (= dorsal plate, tegminal plate, cap-piece) (male genitalia) - dorsal section of tegmen extending posteriorly. Generally comprising the parameroid lobes or a single lobe, sometimes with additional sclerites or showing membranous areas surrounded by sclerite. It is a two-layered structure, and sometimes has different sclerites on the dorsal and ventral layers.  The parameroid lobes are not unequivocally homologous with the parameres of other Coleoptera, hence the difference in terminology. See parameroid lobes, fenestrae, suprafenestral sclerites, subfenestral sclerites, prostegium.

Pars stridens see File (preferred term).

Pectoral canal see Rostral canal (preferred term).

Pectoral receptacle - see 'Mesothoracic receptacle' (preferred term).

Pedal genitalia (= gonatocerous genitalia) (male genitalia) - the state found in majority of ‘Gonatoceri’, where the tectum (q.v.) is not visible, the penis body and its apodemes describe two separate curves when viewed laterally and are articulated with each other, the tegmen has two more or less distinct parameroid lobes. Compare with ‘pedotectal genitalia’ (q.v.).

Pedicel (head, antenna) - second of the three segments of the basic insect antenna (the other two being the scape and flagellum). 'Pedicel' and 'flagellum' are terms rarely if ever used in weevil taxonomy.

Pedon (male genitalia) – ventral plate of pedis. See also pedotectal genitalia and tectum.

Pedotectal genitalia (= orthocerous genitalia) (male genitalia) – term describing the type of penis found in basal ‘orthocerous’ weevils. The dorsal and ventral plates of the penis body (‘tectum’ and ‘pedon’ respectively are separate for most of their length, united by a membrane, and fused at the base (c.f. tectum not visible), the apodemes and the penis body describe a smooth curve in profile (cf a double curve). The parameroid lobes are more or less fused together (cf separate).

Penis (= median lobe; ‘aedeagus’ of some authors) (male genitalia) – the part of the male genitalia comprising the unpaired intromittent organ with its apodemes, and containing the eversable endophallus and the opening of the ejaculatory duct (gonopore). It is enclosed by the tegmen. The ‘body’ and apodemes (= temones, aedeagal apodemes) are sometimes compared in length as a taxonomic character.

Pennon (male genitalia) – fine filamentous sclerotized process within the genital pocket, fringing semi-permanent folds (visible when stained with chlorazol black). (Wanat, 2001, 2007).

Phallobase (= tegmen) (male genitalia) – Anterior or basal part of the aedeagus from which the parameroid lobes or parameroid plate arise. See Tegmen.

Phanerognatha (informal group of weevils) – Curculionidae characterised by the phanerognathous (qv) character state, often also known as ‘long-nosed’ weevils, and also characterised broadly by a long slender rostrum, the mandibles lack a deciduous process, the larval antenna has a more or less conical and projecting apex, and the larvae are concealed within plants. The group is not monophyletic, and has no formal status. See also ‘Adelognatha’.

Phanerognathous (head, mouthparts) – maxillae not covered by the prementum. Characteristic of the ‘Phanerognatha’ (qv).

Plectral tubercles (abdomen, tergite VII) – two or more raised tubercles on tergite VII, each with a small seta posteriorly, that act against the stridulatory file in the elytro-tergal stridulatory system (q.v.) (Lyal & King, 1996)

Pleural process - see Hypomeral lobe (preferred term).

Pleurostomal sulcus (head, rostrum) – part of subgenal sulcus dorsal to the mandible.

Postcolia (=postgenal arm) (head) – the socket for the ventral articulation of the mandibles. (Morimoto & Kojima, 2003)

Postcoxal bridge - see Hypomeral lobe (preferred term).

Post-coxal lamellae (= post-coxal flanges, post-coxal walls of the pectoral canal) (prothorax) – blade-like projections behind for-coxae, extending between coxa and posterior margin of prothorax, as a part of the sternal canal for the rostrum. Apomorphic for Curculionidae: Cryptorhynchinae: Aedemonini, and also for Aonychus (Erirhinini). Similar structures, anteriorly abutting the coxa and posteriorly meeting medially are found in the Camptorhinini (currently in the Cryptorhynchinae but being transferred to the Molytinae, and itself polyphyletic).

Postcoxal process (prothorax) – see Hypomeral lobe (preferred term).

Posterior declivity (elytra) – distal part of elytra where, at rest, sutural margin curves ventrad towards lateral margin.

Posterior tentorial pit (head) – invaginations of the cuticle on the ventral surface of the head corresponding to the positions of the posterior tentorial arms internally. The pits mark the junction of the gular suture and the subgenal suture, They may be very difficult to see in weevils, and may be fused to a single pit or extend effectively along a single gular suture.  See Lyal (1995) for a discussion of this.

Postgula (head) – see cervical sclerites (preferred term).

Postmentum (head) – see submentum (preferred term). Morimoto and Kojima prefer the term Postmentum.

Postocular lobes (= ocular lobes; eye-flaps) (prothorax) – lobulate projections on the anterior margin of the pronotum, lying just behind the eyes and covering them when the head is folded ventrad. Often fringed with setae.

Post-tegminal membrane (= first connecting membrane) (male genitalia) – membrane between tegmen and base of penis (Wanat, 2007).

Praemucro (leg) - see Premucro (preferred term)

Pregula (head) – see Submentum (preferred term)

Prementum (head, mouthparts) – the anterior plate of the mentum, bearing the palpi. See also Submentum.

Premucro (=praemucro, pre-mucro, secondary mucro) (leg, tibia) – small preapical tooth arising ventrally (occasionally distally) at apex of tibia (Kuschel, 1951, Thompson, 1992), basal to mucro/uncus. It can co-exist with a mucro or uncus (i.e. is homologous with neither). It is marked by a paired tuft of long curved setae arising either side of its base and curving more or less over it. In some groups (e.g. many Lixinae, some Molytinae) it is more strongly-developed in females than males, and may be absent or very small in the latter.  (amended December 2012)

Pretarsus (leg) – terminal segment of the leg, consisting of paired or, more rarely, single claws. See Tarsal Claw. (definition changed June 2012).

Pretegminal membrane (= second connecting membrane) (male genitalia) – membrane between 9th segment and the tegmen in males (Wanat, 2001, 2007)

Pronotum (thorax, prothorax) – the dorsal sclerite of the prothorax.

Prorostrum (head, rostrum) - the part of the rostrum from the anterior end of the mesosrostrum (broadening above the antennal insertion) to the apex of the rostrum (Wanat, 2001).

Prostegium (=supra-annular sclerite) (male genitalia) – sclerite in ventral layer of parameroid plate to which the arms between the tegminal apodeme and the parameroid lobes attach.  Present on ‘orthocerous’ weevils and forming part of tegminal ring in more derived groups. (Wanat, 2007; Kuschel, 1989).

Prosternal canal (prothorax) – channel on the prosternum (basisternum and sternellum) to receive the rostrum when the head is rotated down and the rostrum lies along the ventral surface of the thorax. It may extend between the separated coxae onto the sternellum or stop at the fore coxae, thus lying along the basisternum only. See also Rostral canal.

Prosternal process (prothorax) – the part of the prosternum lying between the fore coxae (if these are separated) and extending to the hind margin of the prosternum unless interrupted by the hypomeral lobes. Comprising an anterior basisternum and a posterior sternellum which, if they meet, are separated by the sternacostal suture.

Prosternum (prothorax) – the sternal element of the prothorax, comprising an anterior basisternum and a posterior sternellum which are either separated by contiguous procixae or, if they meet, are separated by the sternacostal suture.

Prothoracic horns (prothorax) – pair of short or long projections generally arising just anterior to fore coxae in some Baridinae and Conoderinae, used by males in fighting.

Proventriculus (alimentary canal) – posterior part of the foregut comprising eight longitudinal folds, variously sclerotised in some groups. See Kissinger, 1963 and Calder, 1989

Proximal comb (leg, tibia) – see secondary comb.

Pygidium (abdomen) – One or more of the apical abdominal tergites which are exposed by the elytra at rest and are more highly sclerotised and strengthened than the other tergites. Thompson (1992) uses a ‘tergal formula’ (TF) in which tergites concealed by the elytra are given in normal type ‘1-6’, those forming the pygidium in bold type ‘7’ and those concealed in the genital chamber in parentheses ‘(8)’.

Ramus (female genitalia, spermatheca) – see Gland-lobe (preferred term)

Rostral canal (= pectoral canal, rostral furrow, prosternal canal) (thorax) - channel on the thoracic sterna to receive the rostrum when the head is rotated down and the rostrum lies along the ventral surface of the thorax. On the prothorax it is generally delimited by longitudinal carinae, probably marking the pleuro-sternal suture.

Rostral furrow see Rostral canal (preferred term).

Rostrum (= beak, snout) (head) – the anterior part of the head, bearing the mouthparts, extended into a tube in most weevils, but may be short or absent (e.g. Scolytinae).

Scape (head, antenna) – the basal segment of the antenna.

Sclerolepidia (metathorax) – specialized scales arising from metasternum along metanepisternal suture (Lyal & King, 1996) (emended June 2012)

Scrobe (head, rostrum) - The sharp depression extending generally from the antennal insertion towards the head capsule (although sometimes deflected ventrad and occasionally with an anteriad element) into which the antennal scape fits when withdrawn against the rostrum.

Scutellar shield (= scutellum in part) (mesothorax) – the part of the mesoscutellum which is exposed between the bases of the elytra. In most weevil literature this is just referred to as ‘scutellum’ (q.v.).

Scutellum (mesothorax) – Posterior part of mesotergum. The term is often used to refer only to the portion of the scutellum that is visible between the bases of the elytra (see ‘Scutellar shield’).  Appropriate terminology is ‘visible’ vs ‘concealed’, not ‘present’ vs ‘absent’.

Second connecting membrane (male genitalia) – see Pretegminal membrane.

Secondary (tibial) comb (= proximal comb, outer setose fringe) (leg, tibia) – row of stout setae subapically on dorsal surface of the tibia just basal to the apical comb. It may join the distal comb to produce the ‘corbel’ (q.v.)

Sheath – see Horn Sheath.

Spermatheca (female genitalia) – Sac-like structure, usually sclerotised in weevils, attached by the Spermathecal Duct to the genital tract and with a Spermathecal Gland. The spermatheca may be considered as having several different areas: Gland-lobe (= ramus) from which the Spermathecal Gland arises; Duct-lobe (= nodulus), where the Spermathecal Duct attaches, collum (basal part of the spermatheca on which the gland-lobe and duct-lobe arise, cornu, the apical often curved and acuminate part.

Spermathecal duct (female genitalia) -  duct between the Spermatheca and the Genital Tract, usually meeting it at the junction between the Common Oviduct and the Bursa.  Variation in the position of this attachment can be useful systematically.

Spermathecal Gland (female genitalia) – gland attached to the spermatheca.  After maceration the gland is largely lost, but the sac-like lumen of the gland relmains, and is usually termed the ‘spermathecal gland’ in taxonomic descriptions.

Spiculum gastrale (=urosternite, sternite IX) (male genitalia) – Internal apodeme of male sternite IX. Comprises a long apodeme (or manubrium) and a posterior sclerotised plate or pair of arms (basal arms). Very variable through Curculionoidea. The basal arms are fused to the genital pocket. Although derived from Sternite IX, it may not be wholly homologous with that sternite. (edited 25/11/2011).

Spiculum relictum (= false spiculum) (male terminalia) - small pouch or apodeme sometimes invaginated between hemisternites on male sternum VIII (Thompson, 1992). Possibly serially homologous with the apodeme of sternum IX.

Spiculum ventrale (= genital spiculum) (female terminalia) – internal apodeme of sternum VIII. Comprises a pair of basal arms, sometimes united to form a basal plate, and an apodeme, sometimes subsumed by the basal arms to give a V-shaped or U-shaped structure. Erbey et al (2010) termed the apodeme the 'genital spiculum'. (modified June 2012)

Spinasternum (prosternum) see Sternellum.

Sternacostal suture (thorax) – suture between basisternum and sternellum.  (Davis, 2009)

Sternellum (= 'furcasternum', 'spinasternum') (thorax) - the second sclerite of the ventral part of each thoracic segment. In weevils it is generally distinct on the prothorax, forming for example the posterior part of the canal in Cryptorhynchinae and a small clear sclerite just behind and between the fore coxae in most others. On the mesothorax it is rarely if ever distinct, but would lie between the mid coxae. On the metathorax it is small and lies between the hind coxae, if discernable. Wood (2007-14), after Hopkins, 1909) figures the sternellum for each thoracic segment. The sclerite on the prothorax has also been called the ‘furcasternum’ and ‘spinasternum’; homologising sclerites in this complex area is difficult.  See the discussion on Characters and character-states: "Sternellum or Prosternal process" for further information and a terminological issue.

Striae – see elytral striae.

Stridulatory File – see File.

Stylus (female genitalia) - a distal segment borne by the Gonocoxite (q.v.) in most species. Generally bears setae, and rarely 'lost' or fused to the Gonocoxite (see 'coxite-stylus').

Subfenestral sclerites (male genitalia) – sclerotised transverse sclerite adjacent to parameriod lobe anterior to an unsclerotsed area (fenestrae (q.v.) of the parameroid plate (q.v.). Homology across Curculionoidea is unlikely. (see Wanat, 2007).

Subgenal sulcus (= subgenal suture; pleurostomal sulcus + hypostomal sulcus) (head, rostrum) – sulcus on the ventral surface of the adult weevil head running between the anterior tentorial pits to the posterior tentorial pits.

Subgenal suture (head, rostrum) – see Subgenal sulcus (preferred term).

Subgeniculate antenna - state in some Apionidae where the apical part of the scape is sharply curved, causing the funicle to lie at an angle to the long axis of the scape, giving the impression of the geniculate state (q.v.) (Wanat, 2001)

Submarginal fold (elytra) - longitudinal furrow and carina internally on elytron close to costal margin, widening basally. The deeper wider "Basal pocket" of the fold fits over the raised sides of ventrite 1 + 2, and the metepisternite, the posterior part locks over the other abdominal ventrites. The particularly broad basal part has been used as a character of the Baridinae + Conoderinae + Ceutorhycnhinae.

Submentum (= postmentum; pregula) (head, rostrum) – the posterior plate of the labium, meeting the gula at the level of the posterior tentorial pits (q.v.). Within the Curculionoidea there is no separate mentum (median plate of the labium) but the submentum cannot be unequivocally synonymised with the submentum of other Coleoptera (where the mentum is present) or the postmentum in those cases. Discussed by Lyal (1995) and Morimoto & Kojima (2003).

Supra-annular sclerite (male genitalia) – see Prostegium.

Suprafenestral sclerites (male genitalia) – sclerotised transverse sclerite adjacent to parameriod lobe posterior to an unsclerotsed area (fenestrae (q.v.) of the parameroid plate (q.v.). Homology across Curculionoidea is unlikely. (see Wanat, 2007).

Tarsal groove (leg, tibia) – furrow on the apico-ventral surface to receive the tarsus if folded back along the leg.

Tarsal Claw (= pretarsus) (leg, tarsus) - paired claws at the apex of the tarsus. They may be simple (more or less gradually tapering from base to apex and lacking teeth or other projections), appendiculate (with a ventral tooth or other projection arising in the basal third, often arising from a process apparently splitting off from the claw, and sometimes directed between the claws), toothed or bifid (with the apex 'doubled' - split from the middle of the claw or nearer the apex to provide two teeth for each claw, one generally shorter than the other).

Tarsomere (= tarsal segment) (leg, tarsus) - the individual portion of a tarsus. There are five tarsomeres in the weevil tarsus, although the fourth is very small and often hidden between the lobes of the third, hence the description 'pseudotetramerous'. The only exception is the Raymondionymidae, where there are four tarsomeres only.

Tectum (male genitalia) – dorsal plate of aedeagus, when present. See also pedon and pedotectal genitalia.

Tegmen (= phallobase in part) (male genitalia) - Anterior or basal part of the aedeagus, comprising a more or less complex ring or sheath surrounding the aedeagus (q.v.), a ventral apodeme directed anteriad (see 'apodeme of tegmen') and dorsal parameroid lobes (q.v.) or parameroid plate (q.v.). The shape of the tegmen, and particularly of the parameroid lobes / plate differs between the pedal and pedotectal type of aedeagus. (emended June 2012)

Tegminal plate (male genitalia) – see Parameroid plate.

Tegminal strut (male genitalia) – see Apodeme of tegmen, Manubrium.

Temones (male genitalia) – see aedeagal apodemes. Term used by Alonso-Zarazaga, 1989, 1990).

Temple (head, head capsule) - lateral part of the head between the posterior margin of the eye and the margin of the pronotum. (Wanat, 2001)

Tentorium (head) – internal skeleton of the head, comprising plesiomorphically a pair of anterior arms joined to a pair of posterior arms, these united by a tentorial bridge.  The anterior and posterior arms are apodemal invaginations arising at the anterior tentorial pits and posterior tentorial pits respectively. Discussed by Lyal (1995).

Tergal formula (abdomen) – see under Pygidium.

Thoracic horns (prothorax) - anteriorly-directed horns arising from the prothorax ventrally, just anterior to the coxal cavity. Often with a median more or less forked sheath between them.   Image below is of a thorax viewed from the ventro-posterior aspect, with the sheath pointing towards the viewer and the horns pointing away.

Thorax of Ternova lineatosignata, viewed internally from posterior

Tormae (= labral rods) (larva, mouthparts) - sclerotized rods in the labrum.  Their shape can provide taxonomically-useful characters.

Transfer apparatus (=complex apparatus) (male genitalia, endophallus) – more or less complex sclerotised elements in endophallus around the gonopore.  cf flagellum.

Uncus (leg, tibia) - Apical tooth of the tibia associated with the Inner Flange (q.v.). The traditional distinction between the uncus and the mucro (q.v.) is that the mucro arises from the ventral (inner) apical angle and is not continuous with the dorsal (outer) margin), while the uncus arises from, or is continuous with, the dorsal margin (Marvaldi & Lanteri, 2005). Thompson (1992) notes that the uncus is always associated with the inner flange, so that a mucro, once associated with the inner flange, is termed an uncus. There are cases where the flange and the mucro do not smoothly connect, even where both are present.

Unguitractor - see Fifth tarsomere (preferred term)

Urosternite - see spiculum gastrale (preferred term)

Vagina (female genitalia) – tubular part of the ovipositor between the junction with the common oviduct and the gonocoxites, where it opens through the vulva.

Vaginal palp see 'coxite-stylus'

Venter (head, head capsule) - area between the eyes ventrally, limited anteriorly by the base of the rostrum (level of the anterior margin of the eyes) and posteriorly by the posterior tentorial pit. Includes part of the submentum sensu Lyal, 1995 and part of the postgena. (Wanat, 2001)

Ventral sulci (head, rostrum) - (Wanat, 2001)

Ventrite (abdomen) – visible (exposed) abdominal sternites.  The first two sternites are concealed, forming part of the coxal cavity, so that the first ventrite is the third sternite. There are five ventrites visible in weevils. The nature of the sutures between the ventrites is discussed by Thompson (1992).

Vertex (head, head capsule) - area behind the eyes dorsally, not including the part of the head capsule normally covered by the pronotum (i.e. lacking the sculpture and setation of the more normally exposed part of the head)

Vulva (female genitalia) – opening of vagina between gonocoxites.

Wing-binding patch (abdomen) – patch of very fine spines generally found paired on abdominal sterna, used by the weevil in folding the wings under the elytra.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith