Revision of Glossary of Weevil Characters from Tue, 2010-07-06 15:41

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. Please comment and add to the contents, which I shall revise regularly.

Chris

Aedeagus (= median lobe) (male genitalia) – the part of the male genitalia comprising the unpaired intromittent organ with its apodemes.

Anapleural suture (metathorax) – see metepisternal suture.

Antenna (head) - sensory projection from rostrum, comprising 11 articles: scape, 7-segmented funicle and 3-segmented club). 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 desmomere.

Antennomere (=antennal article, antennal segment, desmomeres (in part)) (head, antenna) – term not often used in weevils, but refers to the individual parts of the funicle and club, apart form the pedicel, which is a true segment (the term pedicel is rarely if ever used in weevil taxonomy).

Apical setal comb (=distal comb, tibial comb) (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).  (Thompson, 1992).  See also ‘secondary comb’, ‘corbel’.

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

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.

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

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

Claw (leg, tarsus) see 'Tarsal claw"

Club (head, antenna) - the apical antennomeres of the antenna. The club generally has three antennomeres, either separate as in some basal groups or combined as in most Curculionoidea. In many weevils there appear to be 4 antennomeres, each delimited by a sutire and each bearing a ring of elongate setae. However, the form of the grove between the apical 'segment' and the others differs from that between the true antennomeres (Wanat, 2001). The apparent 4-article club has been termed 'pseudotetramerous' by Wanat, 2001. Key character states: loose: articulation between antennomeres and 'antennomere' neck' visible; compact: articulation and basal constrictions not seen, but borders between antennomeres clearly visible; connate: borders or sutures between antennomeres partly or completely lost. (Wanat, 2001)

Connate - of two segments or other articulating parts of the body. Fused together, with or without a line marking the original suture between them.

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.).

Coxites (=hemisternites) (female genitalia) - pair of conical sclerites apically on ovipositor, surrounding vulva.

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) 

Desmomere (= antennomere, funicle segments) (antenna, funicle) - the antennomeres that make up the funicle of the antenna (Alonso-Zarazaga, 1989)

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

Elytral striae (= striae) (elytra) – longitudinal grooves or rows 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.

Elytro-tergal stridulation mechanism (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).

Endophallus (= median lobe) (male genitalia) – membranous sac lying within aedeagus condiguous with ductus ejaculatorius and aedeagus. Everts during copulation.

Epipleural bridge - see Hypomeral lobe

Eye-flaps see postocular lobes.

Fifth tarsomere (= pretarsus, 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 mechanism) – patch of fine, parallel ridges on the internal surface of the elytra, generally near the apex, which form part of the elytro-tergal stridulation mechanism.

Flagellum (male genitalia) – long sclerites sometimes present within endophallus through which ductus ejaculatorius opens.

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

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

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 tentorial pit(s). The sutures are often fused to a single suture in weevils. (Lyal, 1995)

Hemisternites (female genitalia) – see coxites.

Hemisternites (male genitalia) – pair of sclerites on sternum VIII

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

Humerus (= humeral angle) (mesothorax, elytra) – anterolateral angle of folded elytron, sometimes produced. Tends to be rounded and effectively losy in apterous species.

Hypomeral lobe (= pleural process; postcoxal bridge; 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

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
vental margins of the tibia; it lacks setae.  Often it is associated with a tooth (uncus / mucro).  It can occur on all three tibiae.  (Thompson, 1992)

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.

Interstices see Interstriae

Interstriae (= intervals, interstices) (elytra) – raised longitudinal strips 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).

Intervals see Interstriae

Labral rods (larva, mouthparts)  see tormae

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

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.  

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

Manubrium (=apodeme of tegmen) (male genitalia) – apodeme extending anteriad from base of tegmen.

Median lobe – see aedeagus
Mesepimeron (mesothorax) – sclerite on the side of mesothorax (Fig. xxx)

Mesepisternum (mesothorax) – sclerite on the side of mesothorax (Fig. xxx)

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)

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) - fused preepisternum and basisternum (Wanat, 2001)

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.

Metepisternal suture (= anapleural suture) (metathorax) – 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)

Mucro (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’.

Ocular lobes (prothorax) – see postocular lobe

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

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

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

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

Parameres see parameroid lobes

Parameroid lobes (= parameres) (male genitalia) lobes attached to the posterodorsal part of the tegminal ring.

Pars stridens see File.

Pectoral canal see ‘Rostral canal’.

Pectoral receptacle - see 'Mesothoracic receptacle'

Pedicel (head, antenna) - second of the three segments of an 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 aedeagus.

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 mechanism (q.v.) (Lyal & King, 1996)

Pleural process - see Hypomeral lobe.

Postcoxal bridge - see Hypomeral lobe.

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

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).

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.

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

Premucro (=pre-mucro, secondary mucro) (leg, tibia) – small apical tooth arising from ventro-apical angle of tibia.

Pretarsus - see Fifth tarsomere

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)

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.

Rostral canal (= pectoral 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.

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

Sclerolepidia (metathorax) – specialized scales arising from metasternum along episternal suture (Lyal & King, 1996)

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.

Spiculum gastrale (male genitalia) – Apodeme of male sternite IX (?). Comprises a long apodeme and a posterior sclerotised plate or pair of arms. Very variable through Curculionoidea. The apical arms are fused to the genital pocket. Although derived from Sternum IX, it may not be wholly homologous with that sternum.

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

Sternellum (= furcasternum) (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.

Subgenal sulci (= subgenal sutures) (head, rostrum) –

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)

Submentum (head, rostrum) –

Tarsal Claw (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 projectaion 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'.

Tegmen (male genitalia) - ring surrounding aedeagus, comprising dorsal parameres and a ventral apodeme.

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

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.

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

Unguitractor - see Fifth tarsomere

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)

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)

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.