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O.  Other terms.
Definitions of anatomical and other terms.

All terms used in the text (and many other related terms) appear in this section.

Abbreviations used in the glossary below are as follows:
app.= apposition to, meaning a contrasting but not opposing term.
opp.= opposite or antonym.
syn.= synonym.
s.= singular.
pl.= plural.


abdomen-- The most posteriad major body region of an adult insect, i.e. head, thorax, abdomen.

aculea– (pl. -eae) A minute spine-like seta on the wings of some Lepidoptera and usually over-laid by scales. The wings appear "roughened" in areas where aculeae underlie scales.

aedeoeagus– The intermittent copulatory organ of male insects.

ampula– A process, often finger-like, arising from the inner face of the valva.

anal margin– That portion of the margin of the hindwing which runs parallel to the abdomen. The term is often applied to that portion of the margin of the forewing which runs parallel to the abdomen when the wings are folded roof-like over the body.

anal veins– Any of the unbranched veins arising from the wing base below the Cubitus posterioes fold/vein.  In most older texts, the cubitus posteriores is regarded as an anal vein.

anatomy– The study of the structure of an organism; from the Greek meaning literally to cut apart. See also morphology.

anellus– Membranous sheath enclosing the aedoeagus.

annulate– Having discernible rings. Annulate larvae have numerous secondary divisions of each cylindrical body segment.

antemedial line– (am. line) The most proximal complete transverse line of the forewing, running from the costa to the inner margin and basad of the orbicular spot (when the latter is present). See wing pattern elements.

antennal flagellomere– An individual segment of an antenna.

antennal types– Antennae have specialized morphologies for their differing functions from species to species. At least fifteen types are commonly recognized. Those types which are applied to North Dakotan Lepidoptera are as follows: capitate, clavate, fasciculate, lamellate, bi-pectinate, quadri-pectinate, serrate, and simple.

apiculus– A narrowed and often recurved or hooked terminal portion of a clavate antenna.

aposematic coloration– (syn. warning coloration) Having a bright or boldly patterned coloration in conjunction with a noxious property such as disagreeable taste, sharp or stinging spines, or poisonous body fluids. See also cryptic, disruptive, and flash coloration.

appendix bursae– A sac-like structure formed by the evagination of, or constriction in, the wall of the bursa copulatrix. The bursa copulatrix is then a compound structure consisting of the corpus bursa and the appendix bursa.

axillary sclerite– (syn. axillaries) One of the sclerites of the wing base which form the articulation between the wing and the thorax.

basal dash– A streak originating from the wing base usually along the cubitus posteriores and running outward to the basal or antemedial line. See wing pattern elements.

basal line– A transverse line demarked at the costa which is proximad of the antemedial line. The basal line usually fades out before the inner margin. See wing pattern elements.

basitarsus– The most proximal segment of the tarsus. See also leg segments.

biogeography– The study of the geographical distributions of organisms. See also faunal region.

biordinal crochets– Crochets of two lengths which occur in alternating placement. See also biserial crochets.

bi-pectinate antennae– Antennae in which most flagellomeres are provided with two rami, each of which is longer than the flagellomere. See also antennal types.

biserial crochets– Crochets of a single length arranged in two rows. See biordinal crochets.

bursa copulatrix– The sac-like spermatophore receptacle of female Lepidoptera. It is connected to the external opening via the ductus bursae.

capitate antennae– Antennae in which the last few segments are abruptly dilated or clubbed. Butterflies have antennae of this type. See also antennal types.

category names– Names denoting a rank in the hierarchical classification system, i.e. Order, family, genus, species.

caudal– Referring to the ‘tail-bearing’ region of an organism. Opposite– cephalic, near synonym posterior.

chaetosema– (pl. -semata) A cluster or patch of sensory bristles on the head and posterior to the antennae of some adult Lepidoptera.

cladistics– The taxonomic method which groups organisms based upon their possession of shared, derived characters. Also widely known as phylogenetic systematics. See also numerical taxonomy and evolutionary taxonomy.

clasper– See valva.

classification– The systematic arrangement of objects into an information retrieval system based upon characteristics of the objects themselves. See also identification, nomenclature, systematics, and taxonomy.

clavate antennae– Antennae which gradually thicken from the base to the apex. The White-lined sphinx, Hyles lineata has antennae of this type. See also antennal types.

coarctate– A type of insect pupa in which the appendages are hidden under the cuticle of the last larval instar and not visible. Compare with exarate and obtect.

convergent evolution– Organisms which are not closely related, coming to resemble each other via natural selection due to niche or habitat similarities. Sphinx moths of the genus Hemaris and bumblebees of the genus Bombus are examples. The convergence in this case has been enhanced by selective pressure for mimicry. Other examples are the raptorial forelegs found in Preying mantids, Mantispid-flies, Mantis shrimp, and Ambush bugs. Frequently the concept of convergent evolution is used to describe a particular structure rather than the whole organism.

corpus bursae– The sac-like portion of the bursa copulatrix which bears the ostium bursae when the bursa copulatrix is a compound structure consisting of the corpus bursae and the appendix bursae.

cosmopolitan– The state-of-being worldwide in distribution. Hyles lineata is a nearly cosmopolitan species.

costa– The most anterior wing vein, usually marking the anterior margin of an insect wing.

costal margin– The most anterior wing margin or leading margin of the wing. Note, in moths which fold their wings roof-like over the abdomen, the costal margin of the forewing is the one in contact with the substrate.

coxa– (pl. -ae) The basal portion of the insect leg, originates from the thorax and articulates with the trochanter. See also leg segmentation.

crenulate– a wavy line or edge in which the troughs are wider than the peaks.

crochets– Small spinules located on the ventral surface of the prolegs of a lepidopterous larva. The arrangement and length of the crochets is often diagnostic of the family. Each spinule is shaped like a crochet hook. Uniordinal crochets are all of a uniform length. Bi-ordinal crochets ore of two lengths arranged in an alternating series. Uniserial crochets are arranged in a single row, bi-serial crochets are arranged in two rows.

cryptic coloration– Camouflage pattern resembling the general environment. The ventral surface of the wings of the Polyphemus moth, Antheraea polyphemus is cryptically colored to resemble dried leaves. See also aposematic, disruptive, and flash coloration.

cryptic species– A cryptic species is one that so closely resembles a congener (extremely closely related species), that a detailed study (morphological, ecological, genetic) was required to separate the two taxa. The moth, Euxoa oberfoelii is a cryptic species, long confused with E. obeliscoides.

cubitus anteriores– The fifth major vein on the forewing of an insect. In typical Lepidoptera, this vein forms the lower border of the discal cell (= Cubital stem as used here) on both wings. This is a convex vein and it typically bears two branches: CuA1 and CuA2 (Cu1 andCu2 in older texts.). See also wing veins.

cubitus posteriores– A vein lost in higher lepidoptera located below the cubital stem and above the first anal vein (CuP). In cossids it is present as a tubular vein, in noctuids it is marked by a fold running the length of the wing. See wing venation.

cucullus-- The distal portion the male valva or clasper.

dentate– Appearing strongly serrate or ‘toothed.’ The subterminal line on fws of many species of the noctuid genus Polia is dentate.

discal cell– The ‘hoop-like’ vein arrangement found in the middle of a typical lepidopteran wing. The anterior vein of the hoop is the radius, the posterior vein of the hoop is the cubitus anteriores. The hoop is closed distally by one or more cross-veins. In saturniids of the genus Hyalophora, there is no cross-vein and the discal cell is termed an open cell. In cossids, a tubular vein can be seen that bisects the discal cell longitudinally. This is the median vein.

discal lunule– See discal spot.

discal spot– (syns. reniform spot, discal lunule) A spot located at the end of the discal cell. The spots are round in Antheraea polyphemus, kidney shaped (reniform) in Feltia jaculifera, and crescentic (lunate) in Hyalophora cecropia. See also wing pattern elements.

disruptive coloration– A pattern that breaks up the outline of an organism. When resting on sage, the pattern of Hemileuca hera is a disruptive.  The patter is also found in the arctiid genus Grammia, most of which rest in low vegetation. See also aposematic, cryptic, and flash coloration.

distal– (distad, distally, opp. proximal) Meaning away from the mid-line of the body; the wrist is distad of the elbow and proximad of the fingers.

dorsal margin– See inner margin.

ductus seminalis– In female ditrysian Lepidoptera the tube connecting the bursa copulatrix (receptacle for the spermatophore) with the common oviduct.

emarginate– Notched, Lycaenid butterflies have the eyes emarginate to the antennae. The eye is notched and the space is filled with the antennal base.

entire– A straight or even margin.

exarate– An insect pupa in which the appendages are free from the body wall and somewhat movable. Compare obtect and coarctate.

eyecap– In many micro-moths the scape of the antenna is enlarged and ‘spoon-shaped’ forming an eyecap. The scales covering this enlarged segment are often longer, larger, or more numerous. See also pectin.

facies– General appearance or face, usually overall color and shape. See also habitus and morph.

falcate– Hook-tipped or with a curved projection. The wing apices of Drepaninae are falcate.

fasciculate antennae– (syn. prismatic) Antennae more or less triangular in cross-section which have sensory setae occurring in paired bundles on each flagellomere. Note that an antenna can be both fasciculate and serrate or pectinate. See also antennal types

fauna– (app. flora) Animal life of a designated area is its fauna.

faunal regions– (syn. zoogeographic realm) Continental areas with a broadly similar fauna. The six regions typically recognized are: Nearctic, Palearctic, Neotropical, Aethiopian, Oriental, and Australian. Additional realms sometimes recognized are the Holarctic, Palaeotropical, and Oceana.

female genitalia– In Lepidoptera the external structures are the papillae anales (‘ovipositor lobes’), ostium oviductus, and the ostium vaginalis. Internally, vagina, lamella postvaginalis, lamella antevaginalis, ductus bursae, ostium bursae, bursa copulatrix, corpus bursae, appendix bursae, sigma, ductus seminalis, oviductus communis, oviductus lateralis, ovaries, ovarioles, and accessary glands.

femur– The third segment of the generalized insect leg, distal to the trochanter and proximal to the tibia. See also leg segments.

flash coloration– (syn. startle coloration) A marking or pattern normally hidden from view, which, is exposed when the wearer is disturbed. The exposed marking elicits a startle reaction in a potential predator allowing the prey to escape. The hindwings of members of the genus Catocala are an example. See also aposematic, cryptic, and disruptive coloration.

frenulum– One or more bristles situated near the base of the costal margin of the hindwing in most Lepidoptera. The frenular bristles are held by a retinaculum located on the ventral surface of the forewing. See also retinaculum, wing coupling mechanisms.

frons– In Lepidoptera, that area of the head anterior to the antennae and above the anterior tentorial pits, or more generally, that portion of the ‘face’ visible in an anterior view.

fusiform– (syn. spindle-shaped) A body form which is thickest medially and tapers both anteriad and posteriad.

glossotheca– The pupal sheath which holds the proboscis, i.e. ‘tongue case.’ In the sphingid genus Manduca, the glossotheca is largely free of the body wall and appears as a "handle."

gnathos– Paired sclerotized processes of the vinculum which form the lateral and lower support for the tuba analis. May be fused to form a single structure. In some macroglossine sphingids, the fused gnathi and the uncus form a composite "lobster-claw" like structure.

granulose– Roughened with a pebbly appearance.

habitus– Overall general morphology and shape, usually not referring to color. Habitus is the preferred term in a general comparison of one insect to another. Facies is used mostly within the Lepidoptera. See also facies and morph.

hairy eye– In a hairy eye, setae occurs at the corners of each facet so that the general surface of the eye is hairy. In some species, hair is confined to the posterior or ventral third of the surface. See also lashed eye.

haplotype– In older literature used to refer to the type species of a genus, i.e. in apposition to the type specimen of a species. See also logotype, orthotype, and monotype.

harpe– Articulated clasping structure found on the inner face of the valve in most male Lepidoptera. Occasionally used synonymously with ampula. See ampula and clasper.

Holarctic region– North America north of northern Mexico, Eurasia north of the Himalayas, and North Africa. A region composed of the Nearctic and Palearctic faunal realms. See also faunal realms.

holophyletic– All the descendants from a particular ancestor. All members of the genus Hyles form a holophyletic group. See monophyletic group.

holotype– The type specimen of a species as designated by the author of the species in the original description. See type specimens.

homonym– The same scientific name for more than one organism within a kingdom. A primary homonym is one by original combination. A case of secondary homonomy results when two species, each with the same specific epithet are placed within the same genus. In either case, the junior of the two names must be changed.

identification– The process by which an unidentified specimen is determined to be a member of a particular taxon. See also classification, nomenclature, systematics, and taxonomy.

imbricate scales– Broad flattened scales, appearing as shingles on a roof. See also scale types.

inner margin– The trailing margin of the forewing or that margin running closest to the abdomen or the hindwing is the inner margin. On the hindwing this margin is often called the anal margin. In moths which hold their wings roof-like over the body, the inner margin of the forewing is that margin running nearly parallel with but furthest from the substrate and has been called the dorsal margin.

instar– The stage or number of moults (counting eclosion from the egg) a larva has passed through. A 2nd instar larva has eclosed from the egg and moulted an additional time. See stadium.

International commission of zoological nomenclature– The governing body that determines the set of rules pertaining to the description of new species and the formation and application of scientific names for species of the traditional kingdom Animalia. Its acronym is I.C.Z.N.

junior synonym– The most recent of two names proposed for the same taxon.

juxta– In the male genitalia of most Lepidoptera, the sclerotized plate located between the valvae and below the aedoeagus, usually serving as a support for the sheath of the latter.

lamella antevaginalis– In the female genitalia of most Lepidoptera, a sclerite located anteriad to the copulatory opening.

lamella postvaginalis– In the female genitalia of most Lepidoptera, a sclerite located posteriad to the copulatory opening.

lamellate antennae– Antennae in which each flagellomere is wider than its length. See also antennal types.

lanceolate– Gradually tapering to a point. In a lepidopteran wing, lanceolate refers to an elongate forewing which is widest in the basal third and gradually taper to a point. The inner and costal margins are not parallel and there is no well-defined tornal angle.

lashed eye– A compound eye with a band of elongate setae along part of the dorsal, ventral, or posterior margin. Note that the setae do not occur on the ocular surface. See also hairy eye.

lectotype– The type of a species as designated by a subsequent author. The lectotype must be chosen from specimens known to have been used by the original author when drawing up that species description. See also type specimens, syntype, and holotype.

leg armature– The presence and arrangement of setae and/or spines on a given leg segment.

leg segmentation– The basic segmentation of the insect leg is as follows: coxa, trochanter, femur, tibia, tarsus, pretarsus (claws). Some Hymenoptera have a two segmented trochanter; in Odonata there is a pre-femoral segment. In nymphalid butterflies, the pro-tarsus is greatly atrophied and usually the pretarsus is lost; in geometrid moths, the meta-tarus of some species is greatly atrophied.

life cycle– The stages in the development or an organism. In dealing with insects having complete metamorphosis (holometabolous insects) the life cycle consists of the egg, larva, pupa, and adult stages.

life history– A description of the life cycle including the habitat, hosts, and phenological data for each stage.

linear– In reference to lepidoptera wing shape, forewings in which the costal and inner margins are parallel for most of their length. Such wings are usually more than three times as long as wide.

logotype– The type species of a genus by subsequent designation, i.e. in apposition to lectotype which is the type specimen of a species by subsequent designation.

lumper– (opp. splitter) Usually referring to a taxonomist who prefers broadly defined taxa. For example, a lumper might recognize only four families of butterflies in North America: Hesperiidae, Papilionidae, Lycaenidae, and Nymphalidae; a splitter might recognize 10 (or more): Hesperiidae, Megathymidae, Lycaenidae, Riodinidae, Libytheidae, Heliconiidae, Nymphalidae, Apaturidae, Satyridae, and Danaidae.

macrolepidoptera– Broadly defined as the larger Lepidoptera. Usually restricted to ditrysian lepidoptera of the superfamilies Hesperioidea, Papilionoidea, Geometroidea, Drepanoidea, Lasiocampoidea, Bombycoidea, and Noctuoidea.

male genitalia– Terminal structures of the male abdomen include: aedoeagus, ampula, clavis, cucullus, gnathos, harpe, juxta, saccus, sacculus, socii, uncus, valvae, vesica, and vinculum.

medius– The fourth longitudinal vein in a typical insect wing. It is posteriad of the radius and anteriad of the cubitus. In the majority of Lepidoptera, this vein is indicated by a crease which bisects the discal cell.

mesoseries– Refers to the arrangement of crochets on the prolegs of a caterpillar. Crochets arranged in a mesoseries form an opened half circle or crescent facing away from the midline.

meso-thorax– The middle metamere or segment of the thorax. That segment which bears the second pair of legs and the first pair of wings in a winged insect. See also pro- and meta- thorax.

meta-thorax– The last or third metamere or segment of the thorax. That segment which bears the third pair of legs and the second pair of wings in a winged insect. See also pro- and meta-thorax.

microlepidoptera– Generally the smaller Lepidoptera, specifically all non-ditrysian leps and all Ditrysia not included under the macrolepidoptera. This group has also been defined as those Lepidoptera whose larvae lack secondary setae.

micropyle– The opening in the egg covering through which fertilization occurs.

monograph– A single work which covers a specific taxon in detail. Rothschild and Jordan authored a monographic work on the Sphingidae of the world.

monophyletic group– A group of organisms with a single common ancestor. Compare with holophyletic and paraphyletic groups.

monotype– The type species of a genus by virtue of being the only included species in the original generic description. Called type designation by monotypy.

monotypic– (opp. polytypic, polymorphic) A species with a single form or general appearance. Hyles lineata is a widespread monotypic species in North America. Euxoa ochrogaster is a polytypic (more specifically polychromic) moth. This term is also used at higher levels: genus, tribe, family, etc.

morph– As used here, a color form or seasonal variety of a given species that is not segregated by population or geographic location. Latin names attached to such have no scientific validity and are for convenience of popular collectors only.

morphology– (app. anatomy) The study of insect structure and function.

Nearctic region– North America including northern Mexico. See faunal regions.

Neotropical region– Geographic area from central Mexico southward including all of South America and also the West Indies and the Florida Keys. See faunal regions.

neotype– When a holotype has been lost or destroyed, and there is a need based upon nomenclatural stability, then  a specimen (ideally one of the paratypes) can be designated as a neotype (new type). This should only be done as part of a revisionary project. See also type specimen.

nomenclature– The system of scientific names and rules for naming organisms. See also classification, identification, systematics, and taxonomy.

objective synonym– (opp. subjective synonym) A case in which two different names have been assigned to the same specimen, or to the same higher order taxon when based upon the same species.

obtect– The type of insect pupa in which the appendages are visible yet appressed to the body surface and immobile. Compare exarate and coarctate.

ocellatus– An eye spot occurring on the wings of Lepidoptera (or other insects).

ocellus– (pl. ocelli) The simple or single-faceted eye found above the compound eye and behind the antennae in most adult Lepidoptera. An ocellus has a single photo-receptor cell. See stemma.

oligophagous– (app. polyphagous) Having a narrow range of hosts.

orthotype– The type species of a genus by original designation by the author of the genus in the original publication, i.e. direct appositive of holotype.

ostium bursae– The opening from the ductus bursae to the bursa copulatrix. See also bursa copulatrix and ductus bursae.

outer margin– The distal margin of a lepidopteran wing. On the forewing, the outer margin is separated from the inner margin by the tornal angle and from the costal margin by the apex.

Palearctic region– Europe, incl. north Africa, and extending eastward across Asia, north of the Himalayas. See also faunal regions.

Paleotropic region– Africa south of the Sahara, India and China south of the Himalayas, and Southeast Asia and Northern Australia. See faunal regions, i. e. the Old World Tropics..

palpus– The usually 3-5 segmented appendage of the maxilla or labium. In the Lepidoptera the maxillae and labium are normally atrophied beyond easy recognition and only portions remain– such as the palpi and the galeae. When palpus is used without a modifier (i.e. maxillary or labial) it refers to the labial palpus. In Lepidoptera either both palpi are visible or atrophied,  or only the labial is present.

parallel evolution– Sphinx moths such as Hemaris diffinis and Proserpinus flavofasciatus show parallel evolutionary development, both are diurnal nectar feeders and also bumblebee mimics. Differs from convergent evolution mainly in the degree of relationship of the organisms involved. See convergent evolution.

paraphyletic group– A grouping of organisms which do not share an immediate common ancestor. Eumorpha achemon and Hyles lineata form a paraphyletic group in that each shares a common ancestor with members of their respective genera. See monophyletic and holophyletic groups.

paratype– Specimens forming the type series from which a holotype is designated by the original author of the species. The paratypes are designated by the original author. See type specimens.

pectin– Enlarged or elongate scales present on the ventral surface of the first antennal segment or scape. See also eyecap.

phylogenetic order– Generally taken to mean a progression from the least specialized to the most specialized taxa. This ‘linear’ presentation of material does not always illustrate the branching tree which is a closer portrayal of a phylogeny.

phylogeny– The sequence in branchings of the evolutionary tree is the phylogeny of the group under discussion. See monophyletic, paraphyletic, and holophyltic groups.

pilifer– Small lobe-like, often bristled remnant of the labrum located on each side at the lower angle of the face of adult Lepidoptera; it is sometimes long and touching either the proboscis or the inner face of the labial palpus.

pleural lobes– A dorsal projection from the pleura of both the meso- and metathorax which serves as the pivot point for wing flapping. The term is also used to designate a sclerotized flap arising from the pleural region of the 8th abdominal segment in moths of the superfamily Yponomeutoidea.

pleurite– Small sclerite located fore and aft of each pleural lobe and serving as indirect muscle insertion points. Contraction of muscles attached to these sclerite causes the wing to flap down.

pleuron– The lateral surface of the insect body, usually restricted to the thorax.

polymorphic– A species with more than one form or morph. In Lepidoptera most often applied to color varieties of a given species which are usually seasonal in nature. Hemaris diffinis is a polymorphic species having many seasonal forms.

polyphagous– (app. oligophagous) Having a wide host range.

population– A group of freely interbreeding organisms within a defined geographic area.

porrect-- Projecting foreward.

postmedial line– (pm line) A transverse line running from the costal margin around the distal side of the reniform spot and down to the inner margin. See wing pattern elements.

primary type– A specimen which serves or potentially serves as the reference specimen for a given species, i.e. holotype, syntype, lectotype, or neotype.

priority, rule of– The oldest valid name combination is the accepted name for a given taxon.

proboscis– The fused galeae of the maxillae form the coiled tube or tongue found in most Lepidoptera.

prolegs– Paired fleshy protuberances armed with crochets usually found on the ventral surface of abdominal segments 3-6 and 10 of caterpillars.

pro-thorax– The first segment or metamere of the insect thorax. The first pair of thoracic legs are located on the pro-thorax. See meso- and meta-thorax.

proximal– (proximad, proximally, opp. distal) Toward the midline of the body. The wrist is proximad of the fingers and distad to the elbow.

pterostigma– A thickened area along the costal margin of the forewings in some microlepidoptera, i.e. Micropterygidae and Coleophoridae: Blastobasinae.

quadrifid venation– (app. trifid) A condition of wing venation in which the cubital stem appears to have four branches emanating from the lower half of the discal cell.

quadri-pectinate antennae– Antennae in which each individual flagellomere has four projecting rami. See also antennal types

radius– The third vein of the typical insect wing. The radius forms the anterior boundary of the discal cell. Primitively two veins, the radius proper (R, [R1 of older texts]) and the radial sector (Rs1-4 [R2-5 of older texts]).

radial sector– The fourth major wing vein, fused in most Lepidoptera with the Radius (see above). oreniform spot– See discal spot.

reticulate– A speckled pattern.

retinaculum– A group of bristle-like scales or a sclerotized bar on the ventral surface of the forewing of most Lepidoptera which serves as a holder for the frenulum. The frenulum-retinaculum system is the wing interlocking mechanism found in the vast majority of the Lepidoptera.

revision– In taxonomic literature, a morphological re-appraisal of a group of taxa for the purpose of redefining known species and often describing additional ones.

saccus– An anteriorly projecting ventral pouch formed of the ankylosed (fused) sclerite of the vinculum or 9th abdominal segment.

sacculus– A pouch-like expansion located at the base of the valva.

scales– Wings of Lepidoptera are normally covered with rows of overlapping scales. Scales occur in a number of different types: forked, hair-like, imbricate, spatulate, or strap-like.

sclerite– An external portion of the body wall of an Arthropod which is separated from similar portions by a suture or membrane and which has undergone the tanning and hardening process known as sclerotization.

scolus– An enlarged or elongate tubercle covered with socketed setae or spines.

secondary type– Type specimens which under normal conditions would not be a name bearer or standard reference specimen of a species, i.e. paratypes, allotypes, topotypes, and homeotypes. Compare to primary type.

senior synonym– (opp. junior synonym) The older of two names proposed for the same taxon.

sensillae– Modified setae which perform a specific function such as tactile or sound reception.

serrate antennae– Antennae in which each flagellomere is broader at the apex than the base. Each antenna then has a ‘saw-tooth’ appearance. See also antennal types.

seta– A socketed hair which has a single trichogen cell at the base. The socket itself is formed by the closely associated tormogen cell. See also spine and spur.

simple antennae– (syn. filiform, thread-like) Antennae in which each segment is an unmodified cylinder. See also antennal types.

sinuate– Having an ‘S’ curve or continuous curving shape.

socius– (pl. socii) Paired membranous, often setose, extensions of the vinculum usually bracketing or ventral to the anus. Possibly an unsclerotized homolog of the gnathos.

species– One or more populations of freely interbreeding organisms which are reproductively isolated (for reasons other than geography) from other closely related populations. A more modern definition might be a chronologically continuous genome which is isolated from other genomes by non-geographical factors. See also subspecies and species complex.

species complex– (syn. superspecies) A group of closely related species which contrary to accepted species concepts do not in every situation behave as distinct species. Hemileuca maia and H. nevadensis are distinct species yet, both apparently integrate with a third species, H. lucina in the northeastern U. S. and with additional intermediate populations scattered in the south-central U.S. See also cryptic species.

spine– A non-socketed, pointed projection formed entirely of cuticle. The pro-tibia of Coloradia pandora has an apical spine. See also seta and spur.

splitter– (opp. lumper) Referring to a taxonomist who prefers taxonomic categories that are narrowly defined. A splitter might recognize certain sphingid smerinthine genera (Smerinthus, Poanias, Pachysphinx, Laothoe), and in addition, split Poanias into two genera and separate Amorpha as a genus from the Old world Laothoe. A lumper might place all of these genera in a single genus: Smerinthus.

spur– An elongate multi-cellular socketed structure found on the legs of most Lepidoptera. The usually tibial spur formula for Lepidoptera is 0-2-4, meaning two spurs on the meso-tarsus and four spurs on the meta-tarsus. See also seta and spine.

stadium– (pl. stadia). The time interval between moults. The second stadium may last 14 days. See instar.

stemma– (pl. stemmata) The light sensitive organs found in lepidopterous larvae. Each stemma consists of multiple photo receptor cells, all receiving light through a single lens. See ocellus.

sternum– The ventral surface of an insect body. Sclerite of this surface are termed sternites. In Lepidoptera the ventral surface of the thorax is severely compressed and envaginated and so the sternites are virtually invisible

sternite– A sclerite found on the ventral surface of an insect.

subcosta– The second longitudinal vein of a typical insect wing. It is posterior to the costa and anterior to the radius.

subequal-- Two structures of approximately the same size are said to be subequal.

subjective synonym– (app. objective synonym) A case in which two or more names have been proposed based upon specimens which are later determined to belong to a single taxon at the level under discussion.

subspecies– Populations which interbreed freely in a narrow contact zone. Each population having some unique characters. The ‘classic’ example is the Banded purple butterfly: Limenitis arthemis arthemis is a northeastern race, L. a. astyanax a southern race of this butterfly. The narrow contact zone between these races extends from southern New England to the Great Plains. See also species and species complex

subterminal line– (st line) A transverse line extending from the costa to the inner margin between the postmedial and terminal lines. See wing pattern elements.

synonym– When a taxon is inadvertently given more than one Latin name. The names involved are synonyms. See also junior, senior, objective, and subjective synonyms.

syntype– (syn. cotype) Specimens before the original author of a species from which the species description was drawn, and from which a type specimen or holotype was not selected. See type specimens.

systematics– The study of the diversity and evolution of organisms. See also classification, identification, nomenclature, and taxonomy

tarsal comb– A specialized row of enlarged setae on the pro-tarsi in members of the genera Manduca and some Ceratomia.

tarsomere– An individual segment of the tarsus. See leg segments.

tarsus– The penultimate part of the insect leg, distad to the tibia and proximad to the tarsal claws. See also leg segments.

taxon– (pl. taxa) Any group of organisms deserving of a formal name; i.e. Hyalophora cecropia is a taxon, the genus Hyalophora is a taxon, Saturniidae is a taxon. But the category names species, genus, family, and order, are not taxa.

taxonomy– The theory and practice of classifying organisms. Alpha taxonomy is the description of new taxa, beta taxonomy is the revision and classification of taxa, gamma taxonomy is the study of the phylogeny and evolutionary history of taxa. See also classification, identification, nomenclature, and systematics

tegula– A (leaf like in Lepidoptera) sclerite which arises near the base of the forewing and rests on the meso-thorax.

tergite– A sclerite on the dorsal surface of an arthropod. Usually restricted to sclerite of the abdomen.

tergum– The dorsal surface of an arthropod.

terminalia– A collective term referring to the genitalia and other posterior structures of insects.

terminal line– The most distally placed transverse line, usually double with one element running along the outer margin. See wing pattern elements.

tibia– The fourth element of the insect leg, distad of the femur and proximal of the tarsus. See leg segments.

tibial claw– the fusion of two or more spiniform setae of the fore-tibia resulting in a large (often flattened claw-like) composite seta. Technically multi-cellular in origin, it is not homologous with a spur. Examples: fore-tibiae of Stiria rugifrons or Datana perspicua.

tornus– (syn. outer angle, tornal angle) The wing angle formed by the conjunction of the outer and inner (or anal) margins.

tornal dash– (syn. anal dash) A longitudinal streak on the forewing near the tornal angle. See wing pattern elements.

transverse lines– The series of vertical lines (on a properly spread specimen) consisting of the basal, antemedial, postmedial, subterminal, and terminal lines.

trifid venation– (app. quadrifid venation) Wing venation condition in which the cubitus stem appears to have three branches emanating from the lower half of the discal cell.

trochanter– The second article of the insect leg, distad of the coxa and proximad of the femur. See leg segments.

truncate– Referring to a structure or margin that is ‘squared-off’ or has a projecting squared-off element.

tympanum– A thoracic or abdominal hearing mechanism based upon membrane vibration registered via scolio-receptors.

type specimens– Specimens which serve as representative standards for the concept of a given species by its author. See holotype, paratype, syntype, lectotype, and neotype.

uncus– In the male genitalia, the dorsal posterior projection from the vinculum.

valva– (pl. valvae) The clasping organ of the male genitalia, originating as a sclerotized evagination of the 9th - 10th inter-segmental membrane.

vertex– Dorsal area of the insect head above and posterior to the antennae.

vestiture– Referring to the type of scales covering the structure in question. The vestiture of the vertex is often important in specimen identification.

vinculum– The sclerotized ring of the male genitalia formed of the combined 9th and 10th fused tergites and sternites.

wing coupling mechanisms– The means by which insect wings are locked together in flight to present a single air foil. Most Lepidoptera have a frenulum-retinaculum mechanism. Many Bombycoidea have an expanded humeral lobe on the hindwing which broadly underlaps the forewing. In the Sesiidae, a series of inter-locking hooks (hamuli), like velcro, are located along the inner margin of the forewing and the costal margin of the hindwing.

wing pattern elements: transverse lines (from base to outer margin)– basal line, antemedial line, median shade, postmedial line, subterminal line, terminal line; dashes– basal dash, tornal dash, apical dash; wing spots– reniform (or discal lunule), orbicular (two collectively = ordinary spots), claviform, and subreniform spot. Wing areas take the name of the transverse line distad of them, i. e. the post-medial area is bounded distad by the postmedian line and proximad by the median shade.

wing venation– The arrangement of branches and condition of the veins in an insect wing used for classification and identification. The principle veins of the forewing are: costa, subcosta, radius, radial sector, medius, cubitus anteriores, cubitus posteriores, and anal veins. Cross veins take the name of the principle veins above and below them, i.e. medial-cubital or m-c vein. Branches from the principle veins are subscripted, i.e. M1, M2, or M3.





Last updated: 08/23/07

Dr. Gerald M. Fauske
collection manager, NDSIRC
research specialist, NDSU
216 Hultz Hall
Fargo, ND 58105
E-Mail: Gerald.Fauske@ndsu.nodak.edu

Published by the Department of Entomology 

Prospective students may schedule a visit by calling 1-800-488-NDSU.