Morphology terms pertaining to Delphacidae Adults	Compiled by Charles Bartlett for use in website glossary and interactive morphology guide.
Term	Definition
Abdomen	The third tagma of the insect body, generally thought to be comprised of 11 segments.
Acrometopa	The region of the head between the lower margin of the fastigium and the arms of the Y-shaped carina (Emelyanov, 1996).
Aedeagal brace	See armature of the diaphragm.
Aedeagal complex	In descriptive taxonomy, the combination of the phallus, connective, and parameres, and usually including the suspensorium and postgenital segments.
Aedeagus	The distal portion of the male intromittant organ (phallus) bearing the opening for sperm egress (termed the gonopore in descriptive taxonomy).  The aedeagus may be subtended by a phallobase or enclosed within a phallotheca (the phallotheca is fused to the aedeagus in derived taxa, forming a theca).   In descriptive taxonomy, the term aedeagus is often used for the phallus irrespective of whether the structure is morphologically an aedeagus or a theca. Sometimes, the elongate portion of the phallus is called the shaft as distinguished from the socle at the base.  The basal part of the phallus has a cavity called the genital atrium, or chamber, and a pair of apodemes at the base is referred to as the wings or atrial apodemes.
Anal collar	A transverse or annular intersegmental sclerite between the pygofer and anal tube.
Anal processes	A midventral or a pair of processes usually from the caudoventral margin of segment 10, although in some taxa a pair may arise from the midventral margin of segment 10 (in addition to or instead of a caudoventral pair) (= anal spines, anal spinose processes; processes of segment 10).
Anal region (of wing)	The trailing portion of the wing in the vicinity of the anal veins.
Anal segment	See Anal tube
Anal style	Abdominal segment 11 that usually takes the form of an elongate, cylindrical structure projecting from segment 10.
Anal tube	Abdominal segment 10, which is a roughly tubular dorsal projection behind the pygofer (= proctiger, anal segment, segment 10).
Anal veins	The series of longitudinal veins following the CuP.  In the forewing, there are two anal veins (anterior and posterior anal veins, usually annotated AA and AP or 1A and 2A) in the clavus that fuse approximately midlength, making a Y-shaped vein characteristic of all fulgoroids (rarely obsolete in brachypters).  In the hind wing of delphacids, there are usually three anal veins following CuP, with the second anal vein often branched.
Anteclypeus	The ventral portion of the clypeus when divided by a clypeal suture.
Antenna  (pl. antennae)	The paired, segmented, sensory organs located on the side of the head beneath the compound eyes.  The ventral margins of the compound eyes are often emarginate to accommodate the antennae.  The antennae of delphacids consists of a basal scape (segment 1 in descriptive taxonomy) followed by a pedicle (segment 2).  The pedicle bears numerous pit-like sensory fields (rhinaria), and a bristle-like flagellum.
Anterior chamber of genital segment	When a genital diaphragm is present, the male pygofer is said to be divided into and anterior (cephalad) and posterior (or inner and outer) chamber.
Anterior compartments (of vertex)	The area of the vertex delineated by the fastigium anteriorly, the lateral carinae of the vertex laterally, and the arms of the y-shaped carina posteriorly.  The compartment between the submedian carinae and anterior to the arms of the y-shaped carinae is the areolet.
Anterior cubitus	The anterior division of the fifth evident longitudinal vein (sixth if counting the precosta) (CuA, see cubitus).
Apical cells	The "open" cells at the apex of the wing distal to the nodal line (in other fulgorids, any cells distad of the nodal line).
Apical margin	The distal portion of the wing following the curvature of the wing apex.
Apical spines of the 2nd tarsomere	A row of spines at the apex of the second tarsomere, usually referring to the hind leg.  The arrangement of the spines may vary, but in advanced delphacids there are generally a single row of four spines.
Apical spines of tibiae	The row of spines at the apex of the tibiae (= distal spines of the tibiae), usually specifying the hind leg.  The calcar is thought to be derived from one of these spines.  The number and arrangement of these spines varies among taxa, but in advanced delphacids, there are usually three longer teeth and two smaller teeth separated with by a gap.  These groups may be referred to as outer and inner groups.
Arculus	The distal margin of the basal cell of the wing.
Areolet	A small enclosed area.  The part of the head between the arms of the y-shaped carina and the submedian carinae, frequently forming a roughly diamond-shaped piece.  If the arms of the submedian carinae do not meet, the areolet might be considered to extend to the ventral margin of the fastigium.
Armature of diaphragm	Middorsal structures of the genital diaphragm on which the everted male intromittant organ may rest (= aedeagal brace, genital phragm).
Arms of Y-shaped carina	The paired carinae of the vertex posteriorly forked from the median carina, and most often anteriorly meeting the submedian carinae.
Arolium	A terminal subventral pad that is sometimes present on the pretarsus between the tarsal claws, sometimes called a pulvillus.
Axial unit	According to Dworakowska (1988), the portion of the wing including the Sc, R, and MA veins (= radial complex).
Axillary region	The proximal portion of the wing bearing the axillary sclerites.
Axillary sclerites	The small sclerites in the proximal portion of the wing that are involved in wing folding.
Basal angle of parameres	The proximal, ental portion of the parameres that is projected in many taxa (= basal angle of genital styles).
Basal cell	A cell in the proximal portion of the wing, near the axillary region, between the bases of the R+Sc, M and CuA veins.  The distal margin of the basal cell may be referred to as the arculus.
Basal foramen (of phallus)	The opening at the base of the phallus through which the  ejaculatory duct enters into the phallus (Singh-Pruthi, 1925)
Basitarsus	First segment of the tarsus, the proximal tarsomere.
Beak	See rostrum.
Blemma  (pl. blemmata)	A roundish, dark spot found on the gena, anterior to the compound eye and near (usually below) the ocelli (characteristic of Kelisiinae).
Brachypter	An individual having shortened and presumably non-functional wings in the adult, often with the forewings not extending to the apex of the abdomen.  The hindwings are greatly reduced or absent.  Some authors distinguish between different kinds of brachypterous wings refer to any shortened, non-functional wings as brachypterous.
Brachypterous	As generally used for delphacids, brachypterous wings are any form of shortened, and presumably non-functional, wing.  Some authors distinguish between types of shortened wings using stenopterous (or intermediary) for wings that approximately reach the end of the abdomen and brachypterous (or micropterous) for wings that do not reach the abdomen apex, leaving multiple abdominal segments exposed from above.
Calcar	A movable spine at the apex of the hind tibiae found in all delphacid species.  The calcar varies in form among the subfamilies of delphacids, from quadrate or circular in cross-section (in the Asiracinae and Ugyopinae), to flattened or tectiform, most often bearing dark-tipped teeth along the hind margin.  Some authors apply specialized names to particular forms of the calcar, mostly in regard to cross-sectional shape (e.g., circular, quadrate [quadrangular], flattened, tectiform, triangular, semicircular), or in regard to overall shape (e.g., cultrate, falcate, foliacious) (= Spur, posttibial process, posttibial spur).
Carina (pl. carinae)	An elevated ridge or keel.
Cells (of the wing).	Cells are regions of the wing delineated by wing veins.  Cells may be designated "closed" if they are surrounded on all sides by veins, or "open" if they are delineated on one side by the wing margin.  Cells are generally named for the wing vein immediately anterior to the cell (hence subcostal, radial, median, and cubital cells (see, e.g., Ossiannilsson, 1978).  See also basal cell, subapical cells.
Central plate of abdominal tergite 2	A portion of the tymbal mechanism on the central portion of the second abdominal tergite found in the more advanced lineages of Delphacidae.
Chamber (of aedeagus)	See socle
Claspers	See parameres.
Claval fold	The fold on the trailing portion of the wing separating the remigium from the claval region, currently presumed to represent, or be immediately adjacent to, the CuP.  The vannal fold may be used interchangeably with claval fold (and vannus with clavus), however, Dworakowska (1988), defined the "vannal unit" as comprising the anal and jugal portion of the wing (esp. the hind wing), the so-called anojugal complex (= claval suture, claval furrow, corioclaval suture, vannal fold).
Claval furrow	See claval fold.
Claval lobe	The clavus; the part of the anal area of the wing between the claval fold and the jugal fold (if present).
Claval suture	See claval fold.
Claval veins	In the forewing, the 2 anal veins in the clavus (= anales).
Clavus (pl. clavi)	In descriptive taxonomy, the portion of the wing trailing the claval fold, which approximates the CuP.  In the forewing, this area includes two prominent anal veins that are characteristically fused to form a "y"-shaped vein in all Fulgoroidea.   In the hindwing, the clavus may be considered the region from the claval fold (near CuP) to the next fold in the anal region of the wing.
Closed clavus	The condition where the fused anal veins of the clavus do not exceed the claval fold, they either reach the wing margin within the clavus or extend only to the claval fold.
Clypeal suture	A suture of the face, often incompletely formed, that separates the postclypeus from the anteclypeus.
Clypeus	The usually shield-shaped part of the head below the frontoclypeal suture and above the labrum (delineated laterally by carinae) that bears the dialator muscles of the cibarium (traces of which may be visible externally).  The clypeus is divided, often incompletely, into a dorsal postclypeus and ventral anteclypeus by the clypeal suture.
Commissural margin	The margin of the forewings that are middorsally closely approximated when the wings are at repose (viz. the straight portion of the front wing from the apex of the scutellum to the apex of the clavus)  (= commissural border, sutural border).
Commissure	The area of the forewing near the junction of the clavus with the trailing margin of the wing.
Compound eyes	The large, laterally situated, visual sensory structures comprised of an aggregation of facets called ommatidia (= eyes).
Connective	A sclerotized structure connecting the base of the phallus and the base of the parameres (= basal plate prolongation of Singh-Pruthi 1925).
Corium	The main blade of the wing between the leading margin and the claval (or vannal) fold, used by analogy to the Heteroptera (= Remigium).
Corypha	The portion of the head dorsum between the compound eyes from the arms of the Y-shaped carina to the posterior margin of the head (from Greek Koryphe, head or top).  This term used by Emeljanov (1996) in descriptions of the head of immature delphacids, but now used in other groups of Fulgoroidea.
Costa	The anterior-most evident wing vein forming the anterior margin of the wing (abbreviated "C" in wing nomenclature).  It is understood that the vein usually termed the costa in descriptive taxonomy, may actually represent the fused precosta, anterior costa, posterior costa, and anterior subcosta (see Dworakowska, 1988).  In some fulgorids, such as flatids, ricaniids, and nogodinids (but not delphacids), the precosta is better developed and forms at least a portion of the leading margin of the wing.
Costal margin	The anterior (=leading) margin of the wing  (= leading, fore, or anterior margin; antonyms:  hind, trailing, or posterior margin); see also humeral region..
Coxa (pl. coxae)	The basal segment of the leg that articulates with the body.  The coxae of a particular segment can be indicated as pro-, meso-, and metacoxae, although sometimes postcoxae (short for posterior coxae) is used instead of metacoxae.
Crossveins	Characteristic transverse veins connecting the principal longitudinal veins in the wings, usually named based on the veins they connect. The characteristic crossveins are the "h" (humeral) between the Sc and C (frequently absent in delphacids), "r" (radial) between RA and RP, "s" or "i.r." (sectoral or intraradial), connecting RP2 and RP3, "m" or "i.m." (medial or intramedial), connecting MP2 and MP3, plus the "r-m", "m-cu", and "cu-a" crossveins.
Cubitus	The fifth evident longitudinal vein (sixth if counting the precosta), following the media, which is divided into an anterior (CuA) and posterior (CuP) branch (or first and second branch).  The cubital and anal veins have been interpreted differently by a variety of authors.  According to Dworakowska (1988), the CuP is approximately at the position of the claval fold in the forewing.  The term postcubitus has been used for CuP, and this vein is sometimes interpreted as the first anal vein. The CuP of Dworakowska (1988) may be called the postcubitus by some authors.
Diaphragm	A transverse membrane of the male pygofer, variously sclerotized, separating the pygofer into an anterior and posterior (or outer and inner) chamber.  The diaphragm has an opening for the parameres, and may middorsally bear 'armature' on which the everted intromitant organ may rest (= genital diaphragm; genital phragm; genitalphragma, segmental membrane).
Discrimen	The midventral longitudinal groove of the thorax that serves as external evidence of a furca.
'disk' or 'disc'	The central area of any part, or the area within a margin.
Distal spines of basitarus	The apical spines of the basitarsus (usually referring to the hind leg, hence "postbasitarsus").  The spines may be variously arranged, but in higher delphacids they are usually arranged in two groups (sometimes referred to as outer and inner) of two and five homonomous spines.
Ditrysic (ditrysy)	Females having separate openings for copulation (on segment 8) and the egress of eggs (on segment 9), as found in the Stenocraninae.
Ductus ejaculatorius	See Ejaculatory duct
Ductus seminis	See Seminal duct
Ejaculatory duct	In male insects, the efferent tube for the discharge of sperm ending at the gonopore.  In Hemiptera, the aedeagus is invaginated to form an endophallus that is continuous with the ejaculatory duct.  The efferent tube of the endophallus is the seminal duct that opens at the phallotreme (seconday gonopore).
Elongate apodemes of the 2nd abdominal sternite	Dorsally directed apodemes from the sternum of the second abdominal segment that form part of the tymbal mechanism.
Elongate apodemes of the metapostnotum	Ventrally directed apodemes of the metathoracic postnotum that form part of the tymbal mechanism.
Elytra	See tegmina.
Endosoma	An invagination of the phallus forming the seminal duct, which in Delphacidae is contiguous with the ejaculatory duct (= endophallus).
Epicranial suture (of vertex)	The y-shaped suture of the vertex of many immature insects, often absent or obscure in adults, indicating a zone of weakness that splits when the insects molts.  The base is the coronal suture, and the arms normally termed frontal sutures.  The epicranial suture is possibly indicated by the y-shaped carina of adult delphacids (= ecdysial cleavage line).
Epimeron (pl. epimera)	The sclerite of the pterothoracic pleuron posterior to the pleural sulcus.  The segment of the pterothorax can be specified using the appropriate prefix (viz. mesoepimeron, metaepimeron)
Episternum (pl. episterna)	The sclerite of the pterothoracic pleuron anterior to the pleural sulcus.  The segment of the pterothorax can be specified using the appropriate prefix (viz. mesoepisternum, metaepisternum)
Epistomal suture	See frontoclypeal suture.
Eumetopa	The frons; the portion of the face from the frontoclypeal suture to the lower margin of the fastigium (Emeljanov, 1996).
Fastigium	The transitional angle of the head between the vertex and the frons.  The fastigium is usually smoothly rounded, but may be carinate.
Female genitalia	The female reproductive structures associated with abdominal segments 8 and 9; sometimes including segments 10 and 11 in descriptive taxonomy.
Female pygofer	Tergum 9 of the female abdomen.
Femur (pl. femora)	The third segment of the insect leg, an elongate segment between the trochanter and tibia.
Flagellum (of aedeagus) (pl. flagella)	A distal, membranous, retrose process of the aedeagus apex (found only on more basally derived delphacid taxa) (=vesica, pl. vesicae).
Flagellum (of antennae) (pl. flagella)	The bristle-like terminal portion of the antennae; the antenna beyond the pedicel.
Foramen of diaphragm	The opening of the diaphragm to allow the egress of the parameres (= orifice of the diaphragm).
Forewing	The front wing; the wing of the mesothorax.
Fovea (pl. foveae)	Any depression, which may (or may not) be demarcated by carinae.
Frons	The front of the face.  In descriptive taxonomy, that portion of the head that lies between the fastigium and the frontoclypeal suture laterally separated from the genae by the lateral carinae of the frons.  Strictly speaking, the frons lies between frontoclypeal suture and the frontal sutures (epicranial arms; absent in adult delphacids), bearing the median ocellus (absent in delphacids) and the origins of the labral muscles.  Based on the position of the median ocellus in cixiids, the morphological frons would be a small area just above the frontclypeal suture.
Frons base and apex	In descriptive taxonomy, the base of the frons is that portion close to the vertex, and the apex is near the frontoclypeal suture.
Frontoclypeal suture	The suture on the front of the head between the frons and the clypeus, also called the epistomal suture,  extending between the anterior tentorial pits, internally forming the epistomal ridge, continued laterally as the subgenal suture.
Frontoclypeus	The face of the insect including both the frons and the clypeus.
Furca (pl. furcae)	An internal apodeme of the thoracic pterothoracic sternum, often in the form of a "Y" (hence "furca" = a fork) in cross-section.  The furca is formed by an invagination of the midsternum forming an internal ridge on which the sternal apophyses are found.
Gena (pl. Genae)	The lateral portion of the head beneath the eyes and behind the lateral carinae of the frons, above the mouthparts and in front of the occipital margin of the head.
Genal carina	A carina of the gena that extends from the subgenal suture, just behind the lateral carinae of the frons, to near the antennal base (= Oblique carinae of genae, wangenkiel).
Genal suture	The suture separating the maxillary and mandibular plate ( = hintere wangennaht in Asche 1985).
Genital chamber	The cavity in males within the pygofer (segment 9) containing the genital organs.
Genital scale	In females, a sclerotized median sclerite of abdominal segment 7 found at the base of the ovipositor.
Genital segments	The abdominal segments bearing the reproductive organs (viz. seg. 9 in males, segs. 8-9 in females).
Genital styles	See parameres.
Genitalia	The abdominal segments bearing the reproductive organs (viz. seg. 9 in males, segs. 8-9 in females).  In descriptive taxonomy, the term genitalia are sometimes to used to include segments 10 and 11.
Gonacoxa (pl. gonocoxae)	The valvifers.  The paired bases of the gonapophyses of female genitalia, evidently derived from coxal bases of abdominal legs.  The gonacoxae of segment  8 are the first gonacoxae, and those of segment 9 are the second gonocoxae.
Gonangulum	In females, a sclerite attached ventrally to the base of the first gonapophysis and dorsally articulating with the second gonocoxae and abdominal tergum 9, probably derived from the coxa of the abdominal legs of that segment.
Gonapophysis (pl. gonapophyses)	The paired, midventral projections of female abdominal segments 8 and 9 that form the elongate processes of the ovipositor; the valvulae.  The first gonopophyses are those from segment 8, and the second gonapophyses are those from segment 9.
Gonoplac	The paired processes of the female abdominal segment 9 (projecting from the second gonocoxae) that form the ovipositor sheath; the third valvulae (= sawcase).
Gonopore (female)	The opening of the oviduct for the egress of eggs.
Gonopore (male)	In males the external opening of the ejaculatory duct (= primary gonopore), although in descriptive taxonomy used for the opening of the phallus, which is more properly termed the phallotreme (secondary gonopore).
Harpagones	See parameres.
Head	Anterior most tagma of the insect body, the center for ingestion and of sensory perception.
Hind wing	The wing of the metathorax.
Humeral area	The proximal portion of the costal margin of the wing; the 'shoulder'.
Humeral crossvein (h)	A cross vein between the subcosta and costa, usually in the humeral region of the wing.  The humeral crossvein is usually absent in delphacids.
Humeral plate	A plate at the very proximal portion of the costal margin of the wing.  The humeral plate, according to Dworakowska (1988) subtends the precostal and costal veins of the wing.
Humeral region	The proximal portion of the wing near the costal margin.
Inner angle of parameres	The distal, ental projection of the parameres (following Metcalf, 1949)
Inner subapical cell	The cell in the wing formed between the branches of the CuA and the nodal line.
Intermediate carinae of frons	Carinae between the median and lateral carinae of the frons found in a few delphacid taxa.
Intermediate carinae of mesonotum	carinae between the median and lateral carinae of the mesonotum found in a few basal delphacid taxa (e.g., Pentagramma)
Jugal fold	A fold in the anal region of the wing, located proximal to the last anal vein, that separates the claval lobe from the jugal lobe.  Usually only evident in the hind wing.
Jugal lobe	A small proximal lobe of the anal portion of the wing proximal to the claval lobe that, according to Dworakowska (1988) may bear remnants of 1 or 2 jugal veins.
Labium	The posterior portion of the mouthparts that forms a 3-segmented sheath around the stylets.
Labrum	A small sclerite subtending the clypeus that is the anterior-most portion of the mouthparts.
Lateral carinae of the clypeus	The carinae forming the lateral margin of the clypeus (separating the clypeus from the mandibular plate).
Lateral carinae of the frons	Carinae forming the lateral margin of the face and contiguous with the lateral carinae of the vertex.
Lateral carinae of the mesonotum	A pair of roughly longitudinal carinae on the mesonotum, that are usually diverging posteriorly, extending from the anterior to posterior margin of the mesonotum.
Lateral carinae of the pronotum	A pair of roughly longitudinal carinae on the pronotum, that vary from roughly diverging slightly posteriorly to arc laterally, roughly following the curvature of the compound eye.  The nature of the lateral carinae of the pronotum is often used in descriptive taxonomy.
Lateral carinae of the vertex	The carinae forming the lateral margin of the vertex, which are contiguous with the lateral carinae of the frons.
Laterodorsal angle (of the pygofer)	The dorsolateral portion of the pygofer that, from caudal view, embraces segment 10.
Laterodorsal angle of the parameres	See outer angle of the parameres (= lateroapical angle of the parameres).
Laterotergite	A lateral sclerite in the pleural region derived from the lateral margin of the tergum, most often used for lateral sclerites of the abdomen that often bear the spiracles.
Leg	A locomatory appendage of the thorax.  The leg, or any part of a leg, of a particular segment can be indicated with the prefixes pro-, meso, and meta, although sometimes post- is used instead of meta-.)
Longitudinal veins	The main veins that extend lengthwise in the wing.  The main stems of the costal, subcostal, radial, medial, cubital, and anal veins.
Lorum	See mandibular plate
Macrocorypha	The portion of the head dorsum between the compound eyes including the entire corypha extended forward to an imaginary line at the ventral margin of the fastigium (evidently excluding the trigon) (or the top of the head between the eyes from the ventral margin of the fastigium to the posterior margin of the vertex).  See Emeljanov (1996).
Macropter	An individual having complete, functional wings in the adult.
Macropterous	Having fully developed, functional wings and capable of flight.  Wings may be termed submacropterous if they are slightly reduced in length with reduced flight capability (wing muscles may be reduced in submacropterous).
Male genitalia	The collective male reproductive organs originating from abdominal segment 9.
Mandibular plate	The sclerite lateral to the clypeus, subtending the gena, and anterior to the maxillary plate, bearing the muscles of the mandibular stylets.  A suture separates the mandibular and maxillary plates that Asche (1985) called the posterior genal sulcus (hintere wangennaht)  (= lamina mandibularis, lorum).
Mandibular stylets	The highly modified mandibles of Hemiptera recognized by being situated anterior to the maxillary stylets and having muscles originating on the mandibular plate.
Maxillary plate	The sclerite on the side of the head behind the genae, above the base of the rostrum, usually partially hidden by the lateral portion of the pronotum (= lamina maxillaris).
Maxillary stylets	The highly modified maxillae of Hemiptera recognized by being situated posterior to the mandibular stylets and having muscles originating on the maxillary plate.
Media	The fourth evident longitudinal vein (fifth if counting the precosta), following the radius, which in the Comstock system may be divided into 4 branches.  In Kukalová-Peck's system, the anterior media (MA) is understood to be absent (fused with RP), although traces may be detected with careful study, with the media represented only by posterior media (MP).
Median carina of frons	The carina extending along the midline of the face from the frontoclypeal suture to the junction of (and contiguous with) the submedian carinae, usually near the fastigium).  The median carina is sometimes paired in adults (always in nymphs).
Median carina of mesonotum	A middorsal, longitudinal carina on the mesonotum, beginning at the anterior margin, usually becoming obsolete on the scutellum.
Median carina of pronotum	A longitudinal carina along the midline, frequently complete from anterior to posterior margin.
Median carina of the clypeus	A longitudinal carina along the midline of the clypeus (may be obscure or obsolete in some taxa).
Median carina of the vertex	The carina extending along the midline of the vertex, frequently extending from the posterior margin of the head and forking near the anterior margin of the eyes, with the forked portion terminating at the submedian carinae.  The single median carina plus the forked apex forms a y-shape; hence these carinae may be designated as the stem (or base) and arms of the y-shaped carina.
Median processes of pygofer	See Medioventral process of pygofer
Medioventral process of the pygofer	A lobe or tooth found on the midventral caudal margin of the pygofer of some species that may be developed as a pair of processes (= median processes or pygofer).
Mesonotum	The tergum of the mesothorax.
Mesothorax	The middle segment of the thorax, bearing the middle leg and the front wing.
Metanotum	The tergum of the metathorax, hidden beneath the wings in repose.
Metapostnotum	The postnotum of the metathorax.  A sclerotized region on the posterior margin of the metathorax, coressponding to the acrotergite of the metathorax, that bears internal, ventral processes (the "elongate apodemes of the metapostnotum") that form part of the tymbal mechanism.
Metathorax	The posterior segment of the thorax, bearing the hind legs and the hind wings.
Metopa	The portion of the front of the head from the frontoclypeal suture to the arms of the y-shaped carina.  This term used by Emeljanov (1996) in descriptions of the head of immature delphacids, but now used in other groups of fulgoroids.  From Greek, referring to the space between two triglyphs in Greek Doric architecture.
Midtibia (pl. midtibiae)	The tibia of the middle leg.
Monotrysic (monotrysy)	Females having a single genital opening for copulation and the egress of eggs, most delphacids except Stenocraninae.
Mouthparts	The feeding mechanism; the labrum, stylets, and labium collectively.
Nodal line	The line of veins of the forewing running approximately from the apex of the costal cell to the apex of the clavus, including the s, r-m, and m-cu crossveins, segregating off approximately the apical third of the forewing.  The transverse flexion of the wing is located near the nodal line.
nodal vein, nodal crossvein	The first branch off R+Sc toward the costal margin, usually reaching the costa just before the pterostigma, if present.   This vein is interpreted as being ScP by Dworakowska (1988), but misinterpreted as being a novel structure by a variety of authors.
Node	The costal fracture; the region where the Sc (the "nodal vein", now understood to be ScP) reaches the costal margin (= nodus).
Notum (pl. nota)	The tergum of a thoracic segment.  A specific thoracic segment can be specified by the addition of the appropriate prefix (pro-, meso-, or meta-).
Ocellus (pl. ocelli)	In adult insects, a simple eye consisting of a single lens, located on the genae in front of and near the ventral margin of the compound eyes (Cixiids and some kinnarids also have a median ocellus just above the frontoclypeal suture).  Ocelli probably function to detect changes in light intensity (= simple eyes).
Open clavus	The condition where the fused anal veins of the clavus extend beyond the claval fold (the fused anal veins may also fuse with CuP).
Outer angle of parameres	The distal, outward projection of the parameres (Laterodorsal [or lateroapical] angle of the parameres; Metcalf, 1949)
Outer subapical cell	The cell of the wing formed between the first fork of the Sc=R vein and the nodal line.
Ovipositor	The egg-laying structure derived from segments 8 and 9 of the female abdomen.  Bourgoin (1983) has termed the piercing-type ovipositor of delphacids and cixiids as an 'orthopteroid' ovipositor, as opposed to the more derived 'raking' type found in more advanced fulgoroids.
Parameres	Paired processes of the genital segment of males that function as claspers or titillators.  According to Snodgrass (1935), parameres are derived from the lateral processes of the primary phallic lobes (phallomeres).  In Auchenorrhyncha, it is unclear whether the 'parameres' are truly parameres, or are derived from a different structure, hence are 'harpagones' sensu Snodgrass (1935), and most descriptive taxonomists refer to them as 'genital styles' or 'styles'.
Paranotum (pl. paranota)	The lateral regions of the the pronotum.  In delphacids used to indicate the portion of the pronotum lateral to the lateral carinae.
Pedicle	The second segment of the antennae (= antennal segment 2), which bears a series of sensory fields (rhinaria) which may be arranged in various ways, but most often in 6 rows of 1 to 4 sensory fields.
Penis	The male intromittant organ, used by analogy to vertebrates.  See aedeagus.
Penis-sheath	See phallotheca.
Periandrum	See phallotheca.
Peripheral veins	The veins toward the outer margins of the wing formed by branches of the main longitudinal veins.
Phallobase	A proximal portion of the male intromittant organ (phallus), in contrast to the aedeagus.  According to Tuxen (1970), the connective is part of the phallobase.  The phallobase may subtend the aedeagus, or be enlarged to completely enclose the aedeagus, in which case it is called a phallotheca.
Phallotheca	An enlarged phallobase surrounding the aedeagus (= penis-sheath, periandrum, ≈theca).  When the phallotheca has fused with the aedeagus, the whole structure may be called the theca (although some authors use phallotheca and theca interchangeably).
Phallotreme	The secondary gonopore; the opening of the seminal duct of the phallus, the external opening of the endophallus (= phallosoma mouth).
Phallus	The male intromittant organ, including the aedeagus and phallobase (used approximately interchangeably with phallosome).
Pleural sulcus	An external groove on the pleuron separating an anterior episternum from a posterior epimeron.  On pterothoracic segments, extending from the pleural wing process to the coxa and forming an internal strengthening ridge (= pleural suture).
Pleuron (pl. pleura)	The lateral region of the insect body between the tergum and the sternum.   On the abdomen, this is a small, membranous area.  On the thorax, the pleural region includes the legs and the sclerotized region between the legs and wings.
Plical unit	According to Dworakowska (1988), that portion of the wings that includes the cubital veins subtended by the claval fold..
Postbasitarsus	The basitarus of the hind leg.
Postclypeus	The dorsal portion of the clypeus when divided by a clypeal suture, sometimes exhibiting external traces of the dilator muscle of the cibarium.
Postcoxae	The coxae of the hindleg; the metacoxae.
Postcubitus	The posterior cubital vein (=CuP; See cubitus).
Posterior chamber of genital segment	When a genital diaphragm is present, the pygofer is divided into an anterior (cephalad) and posterior (or inner and outer) chamber.
Posterior compartments of vertex	The area of the vertex defined posteriorly by the back of the head, laterally by the lateral carinae of the vertex, and anteriorly by the arms of the y-shaped carina or the submedian carinae, divided into two "compartments" by the stem of the y-shaped carina (= basal compartments of vertex).
Postgenital segments	The abdominal segments following the genitalia (viz. segs. 10-11).
Postnotum	An intersegmental plate of the thoracic dorsum functionally associated with the tergum (alinotum) of the preceding segment, bearing the antecosta and internal ridges for muscle attachment; the acrotergite.   In delphacids there is an evident mesopostnotum and metapostnotum.
Postscutellum	A small sclerite posterior to the scutellum on the mesothorax.
Posttarsus (Pl. posttarsi)	The tarsus of the hind leg.
Posttibia (pl. posttibiae)	The tibia of the hind leg.
Precosta	The anteriormost vein of the wing, which is more-or-less completely fused with the costa in delphacids, although some residual elements of the precosta are evident in some fulgoroids, esp. flatids, ricaniids, and some nogodinids (= Praecosta; see Dworakowska, 1988).
Pregenital segments	The abdominal segments preceding the genital segments (viz. segs. 1-8 in males, 1-7 in females) (= visceral segments).
Preocular field	The portion of the head between the compound eye and the lateral carina of the frons.
Prescutum	An anterior subdivision of the mesonotum, represented by a narrow ridge and usually hidden underneath the hind margin of the pronotum (= pretergite).
Pretarsus	The apical part of the tarsus including the tarsal claws (ungues), movable against the apical tarsomere.
Profemur (pl. profemora)	The femur of the prothoracic legs (similarly mesofemur and metafemur are the femora of the meso- and metathorax).
Pronating unit	According to Dworakowska, the anterior part of the wing including the costal and precostal veins that are hinged to the humeral plate (= costal complex).
Pronotum	The tergum of the prothorax.
Prothorax	The anterior segment of the thorax, bearing the front leg.
Protibia (pl. protibiae)	The tibia of the prothoracic leg (similarly meso- and metatiba are the tibiae of the meso- and metathorax).
Pteralia	The collective articular sclerites in the axillary region of the wing.
Pterostigma	A thickened, usually opaque spot on the costal margin of the wing, usually between the subcosta and the first branch of the radius (= stigma).
Pterothorax	The wing-bearing segments (meso- and metathorax) on the thorax inclusively.
Pulvillus (pl. pulvilli)	Any membranous, ventral appendage of the pretarsus, see arolium.
Pygofer (female)	In females, the tergum of segment 9.
Pygofer (male)	The 9th abdominal segment in male Delphacidae that in all taxa is fused into a ring (= pygophore, genital capsule)\.
Radial sector	The posterior radial vein (RP), the posterior radial vein after the first branch (= Rs).
Radius	The third longitudinal vein of the wing, understood in the Comstock system to be primitively 5-branched; or according to Kukalová-Peck, divided into a single anterior radius (RA) and a 4-branched posterior radius (RP).
Remigium	The wing anterior to the claval fold (see corium).
Rhinarium (pl. rhinaria)	Pit-like sensorium, particularly those on the pedicle of the antennae (= sensory fields, sensory pustules; see Shih and Yang 1996).
Rostrum (Pl. rostra)	The elongate mouthparts of Hemiptera and other orders (= beak).
Sawcase	See gonoplac.
Scape	The first or basal segment of the antennae  (= segment 1 or I, first antennal segment).
Scutellar border	A proximal portion of the trailing margin of the forewing that is adjacent to the scutellum when at rest (= scutellar angle).
Scutellum (pl. scutella)	The posterior part of a subdivided notum.  On the mesonotum, it is a posterior, triangular area often incompletely separated from the scutum.
Scutum (pl. scuta)	The middle portion of a subdivided nota (between the prescutum and scutellum) forming main portion of the tergum.
Seminal duct	The sperm conducting tube of the endophallus, which is contiguous with the ejaculatory duct, opening at the phallotreme (=secondary gonopore).
Seminal duct	The duct of the endophallus, contiguous with the ejaculatory duct, extending from the primary gonopore through the phallus to the phalotreme.  The sperm-conducting tube, in part (= ductus seminis).
Sensory fields	See rhinarium (= sensory pustules).
Simple eyes	See ocelli.
Socle	The internal, proximal portion of the aedeagus, internally bearing the ejaculatory duct and including an internal distal sclerotized region ("basischitinisierung des zentralteils" of asche, 1985).  Apodemes termed the "wings" are proximally located on the socle.
Socle	The enlarged basal part of the aedeagus.
Sperm conducting tube	In descriptive taxonomy, ejaculatory duct and seminal duct collectively (= central sperm conducting tube).
Spinal formulae	A shorthand convention indicating the number of teeth on the apices of the hind tibia, basitarsus and second tarsomere respectively, for example 5-7-4.  This formula might also be written (2+3)-(5+2)-4 indicating the groupings of homominous  spines on each segment.
Spiracles	The lateral openings of the body connecting to the tracheal system used for respiration.
Stem of the Y-shaped carina	The unpaired portion of the median carina of the vertex.
Stenopterous	Having abbreviated or narrowed but complete (and non-functional) wings in the adult.  Delphacids with stenopterous wings often have forewings about as long as the abdomen, with the hindwings slightly to greatly reduced.  The terms "subbrachypter" or "intermediary" are sometimes applied.
Sternite	A subdivision of the sternum.
Sternum (pl. sterna)	The underside of the body; the ventral portion of any segment of the insect.
Stigma	See pterostigma
Stylets	One or more of the mouthparts modified for piercing, sucking, and the injection of saliva; elongate structures representing highly modified mandibles and maxillae.  The stylets are adhered together in life to form a feeding structure  with an anterior food channel and posterior salivary channel, and are moved independently by muscles originating on the mandibular and maxillary plates.
Subanal process	Paired or single elongate rodlike processes originating from the link between the aedeagus and the base of segment 10, characteristic of the Kelisiinae.
Subapical cells	The pair of closed cells termed (in delphacids) the inner and outer subapical cells.  The outer subapical cell is delineated within the first fork of the Sc+R and the nodal line.  The inner subapical cell is between the first fork of the CuA and the nodal line.
Subcosta	The second longitudinal vein in modern insects, following the costa, articulating basally with the first axillary sclerite, understood primatively to be divided into an anterior (ScA) and posterior (ScP) subcosta, although little trace of the ScA remains in modern planthoppers.  The subcosta in delphacids is usually fused with the radius over most of its length.  The first anterior branch of the Sc + R is currently understood to be the ScP, and is most frequently unbranched in delphacids.
Subgenal suture	The suture between the genae and the mandibular plate that is anteriorly contiguous with the frontoclypeal suture (= subgenal sulcus).
Subgenital plate	A small sclerite subtending the ovipositor in females.  (In male delphacids, the subgenital plate is fused with the pygofer.)
Submedian carinae	Carinae of the vertex, usually initiating at the lateral carinae of the vertex near the midpoint of the compound eyes and converging anteriorly, most frequently meeting near the fastigium and contiguous with the median carina of the frons.
Suspensorium	In the Delphacini, a modification of the phallobase so that there is a plate-like, strap-like, or ring-like connection of varying lengths between segment 10 and the base of the aedeagus, as opposed to the phallobase being broadly and rigidly incorporated into the base of segment 10  (= aedeagus basal strut of Singh-Pruthi 1925).
Sutural border (of forewing)	See commissural margin.
Tarsal claws	The pair of claws on the pretarsus at the apex of the tarsi (= unguis; pl. ungues).
Tarsomere	Any subsegment of the tarsus (= tarsal segment).
Tarsus (pl. tarsi)	The apical segment of the leg (the "foot") attached to the tibia and bearing the pretarsus; composed of three tarsomeres (tarsal segments).  The 1st  (=basitarsus) and second tarsomere each bearing a row of apical spines, and the third segment bearing the pretarsus.
Teeth of calcar	A row of (usually) black-tipped serrations along the posterior margin of the calcar of most groups of delphacids.
Tegmen (pl. Tegmina)	The thickened forewing of brachypterous individuals.  The term 'elytra' (sing. elytron) is sometimes misapplied, especially in older literature.
Tegula (pl. tegulae)	A small scale-like sclerite structure overlapping the base of the forewings (hidden in some brachypterous forms).  The tegulae are derived from the anterior margin of the forewing as part of the articulation of the wing.
Temple	The portion of the gena anterior to the genal carina (Asche 1985, Anufriev and Emeljanov 1988) (= schläfe).
Tergum (pl. terga)	The dorsal sclerite of each segment of the insect's body.  A subdivision of the tergum is a tergite.  By convention the terga of thoracic segments are referred to as nota.
Terminalia	The genital and postgenital segments of the abdomen collectively (viz. segs. 9-11 in males, 8-11 in female).
Theca (pl. thecae)	The functional male intromittant organ formed when the phallotheca and the aedeagus have become fused.  Characteristic of all Delphacini.  See also phallotheca.
Thorax	The second tagma of the insect body, composed of three segments (the prothorax, mesothorax, and metathorax) each of which bears legs and the posterior two usually bearing wings.  The three segments of the thorax have similar features, so structures of one particular segment can be specified by addition of the appropriate prefix (i.e., pronotum for the notum of the prothorax).
Thyridium (pl. thyridia)	Roundish spots on vertex (used primarily for cicadellids, occasionally for delphacids by analogy).
Tibia (pl.  tibiae)	The fourth segment of the insect leg, an elongate segment between the femur and the tarsus.
Tibial spines	Rigid spines, usually 2 (in Delphacidae), found on the outside lateral margin of the tibia, generally one near midlength and one close to the tibiofemural joint.
Transitional unit	According to Dworakowska (1988), the portion of the wing including the posterior medial vein.
Trigon	The lateral portion of the vertex between the lateral carinae and the submedian carinae (evidently delimited anteriorly by an imaginary extension of the arms of the y-shaped carina, yielding a roughly triangular shape).
Trochanter	The second segment of the insect leg, a small segment between the coxa and femur.
Trochantin	A small sclerite of the pleuron, a remnant of the subcoxa, that forms an anterior point of articulation between the leg basis and the pleuron.
Tymbal	The mechanism present in most Auchenorrhyncha, including all delphacids, that is responsible for producing sound or substrate-born vibration.  The tymbal mechanism includes the first and second abdominal segments and portions of the metathorax and third abdominal segment (= Tymbal mechanism, drumming organ).
Valvifer	The gonacoxa.
Valvula (pl. valvulae)	The gonapophysis.
Vannal fold	The claval fold, particularly of the hind wing.
Vannal lobe	The clavus, particularly of the hind wing (= vannus).
Vannal unit	According to Dworakowska (1988), the portion of the wing including the anal veins and jugal portion of the wing (= Anojugal complex).
Ventral angle of pygofer	The latero-ventral portion of the opening of the pygofer that in caudal view often form small projections (= lateral processes of pygofer).
Vertex	The top of the head (i.e., dorsal region) between the eyes from the posterior margin of the head to the fastigium.
Vesica	See flagellum (of aedeagus)
Wing	The flight organs on the meso and metathorax.
Wing venation	Wing venation refers to the pattern of vein branching in insect wings.  The wing vein branching pattern may provide information helpful in insect systematics.  Naming the veins can be subject to interpretation, and authors may differ in their interpretation.  The traditional wing vein naming terminology is the Comstock (or Comstock-Needham) system, and this is the method most frequently used in descriptive taxonomy (e.g., Asche, 1985: 40).  This method was developed through tracheation studies, and hypothesizes 7 main longitudinal veins (or groups of veins): the precosta (Pc, absent in most modern insects), costa (C), radius (R), media (M), cubitus (Cu), and anal veins (A); jugal veins are present in some fossil insects.  Kukalová-Peck (1983) and Wootten (1979), partly based on Martynov's (1924) ideas, have presented a modern interpretation that assumes that each of these longitudinal veins is associated with axillary sclerites, and has an anterior and posterior branch corresponding with up and down folds of the primitive wing (thus CA, CP, ScA, ScP, RA, RP, MA, MP, CuA, CuP).  Dworakowska (1988) has reinterpreted the wing venation of Auchenorrhyncha based on ideas presented by Kukalová-Peck, 1983.
Wing-coupling mechanism	A structure that joins the front and hind wings during flight located near the apex of the junction of the joined anal veins with the wing margin in the front wing and near midlength of the costal margin of the hind wing. These structures were described in detail by d'Urso (2003).  The wing-coupling mechanism of the front wings is within a darkened area of the wing that is sometimes mislabeled as the pterostigma.
Wings (of the adeagus)	Apodemes located at the proximal-most portion of the socle of the aedeagus.
Y-shaped carina	The median carina of the vertex including the apical fork, forming a Y-shaped carina from the posterior margin of the vertex with the arms usually terminating at the submedian carinae.