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  • calimistrum (kahl-uh-MISS-truhm): L. calimister = a curling iron for hair; 1. arachnids: spiders — a row of curved, thick setae (rarely in an oval patch) placed dorsally along metatarusu IV of cribellate spiders, used for combing out silk from the cribellum.
  • calypter: one of two small lobes at base of wing on the posterior side (ref. Diptera)
  • capitate (KAP-tayht): L. capittus = having a head; 1. botany — forming a headlike mass or or dense cluster, as the flowers of plants in the compositae family; 2. zoology — a linear structure having a distal swelling, e.g., enlarged and globular at the tip, as a bone at the wrist having a rounded, knoblike end.
  • caput (KAH-puht): L. caput = the head; see cephalic region.
  • carapace (KAHR-uh-payse): 1. arachnids: spiders— dorsal portion of the cephalothorax; 2. Insects: a hard dorsal surface formed by the fusion of certain sclerites (ref. Crustacea).
  • caverniculous (kah-vuhr-NIH-kyoo-luss): 1. zoology — cave dwelling.
  • carina/carinae (kahr-EE-nuh): L. carina = hull, keel, boat; 1. zoology — a ridge or keel.
  • caudal (KAH-dull): L. cauda = tail; 1. anatomy — toward, in the direction of, the posterior end; i.e., the tail or posterior part of the body.
  • cell: 1. insect wings: a space in the wing partly or completely surrounded by veins; accessory cell: a closed cell in the front wing (ref. Lepidoptera) on anterior side of discal cell; b. anal cell: one in anal area of wing (ref. Diptera); apical cell: 1 or more cells near wing tip (ref. Hymenoptera); basal anal cell: an anal cell near the base of the wing (ref. Plecoptera); basal cells: the R and M cells in Diptera; cells M D, S M D, and L in the hind wing of Hymenoptera; closed cell: one bordered by veins and not extending to the wing margin; discal cell: one near basal or central part of the wing (ref. Diptera and Lepidoptera); discoidal cell: one near middle of wing (ref. Hymenoptera); lanceolate cell: one in the anal area of the wing (ref. Hymenoptera); marginal cell: one bordering the front margin near the tip of the wing (ref. Diptera and Hymenoptera); median cell: one in the basal portion of wing (ref. Hymenoptera, M D); open cell: one extending to the wing margin; posterior cells: those bordering the rear edge of wing between R and Cu2 (ref. Diptera); submarginal cell: 1 or more cells just behind the marginal cell (ref. Diptera and Hymenoptera); submedian cell: the cell in the basal part of the wing just behind the median cell (ref. Hymenoptera);
  • cephalic (suh-FOW-lik) region (= caput = cephalon = pars cephalica): Gr. κεφαλη “cephale” = head; 1. arach. — the anterior (head) portion of the carapace.
  • cephalon (suf-FOHW-luhn) — see cephalic region.
  • cephalothorax (suf-uh-low-THOR-ahx) (= prosoma): Gr. κεφαλη “cephale” = head + Gr. θωραξ “thorax” (also L. thorax) = breastplate; 1. arachnids: spiders — the anterior division of the spider body. 2. Crustacea.
  • cercus (pl. cerci): one of a pair of dorsally located appendages at the posterior end of the abdomen.
  • cervical grooves (L. cervix = nape of the neck) 1. arachnids: spiders — shallow grooves separating the cephalic and thoracic regions of the cephalothorax.
  • chelate (KHEE-layte): Gr. χηλη “chele” = a claw, a hoof, or a talon; 1. arachnids: spiders — pincer-like; in spiders refers to the fused chelicerae of some haplogyne species whose fangs and laminae form a pincer.
  • chelicera (pl. chelicerae) (kee-LI-suh-ruh) (pl. chelicerae [kuh-LI-suh-ree]): Gr. χηλη “chele” = a claw, a hoof, or a talon + Gr. κερας “ceras” = an animal’s horn; 1. arachnids: spiders — the anterior-most appendages of a spider, i.e., the spider’s jaws, consisting of a basal segment (paturon) and an apical fang.
  • cheliceral extension: 1. arachnids: spiders — a pointed, basal projection behind the clypeus, conspicuous in some Theridiidae, Nesticidae, and Pholcidae.
  • cheliceral furrow (= fang furrow): 1. arachnids: spiders — the groove of the chelicera into which the fang closes.
  • cheliceral lamina; see lamina.
  • cheliceral teeth: 1. arachnids: spiders — tooth-like projections of varying size on the margins of the cheliceral furrow.
  • Chelicerata (Kuh-liss-uh-RAH-tah) — a subphylum first described in 1901 by the German zoologist Richard Heymons [1867 – 1943] using the Greek noun χηλη (KEY-lay) = a claw, talon, or hoof + the Greek noun κερας (Ser-as) = an animal’s horn + the Latin suffix ata — which by convention is suffixed to the names of animal subdivisions — to refer to animals that have specialized appendages before the mouth that they use in feeding, capturing and securing prey and that — in the case of spiders — are further equipped to inject venom and digestive agents into their prey;
  • chemoreception (KE-moh-rhe-CEP-shun): 1. zoology — sensing of chemical stimuli.
  • chevron (SHEV-rahn): 1. anatomy — a v-shaped pattern.
  • chilum (KHEE-lum) (pl. chila): Gr. χειλος “chilos” = lip, bill, beak, edge, rim, fodder; 1. arachnids: spiders — a small sclerite, at the base of the chelicera, under the clypeus.
  • chrysalis (pl. chrysalids or chrysalides): the pupa of a butterfly.
  • clade (klayde): Gr. κλαδος “clados” = a young branch or shoot; 1. taxonomy — the term was first introduced by the British biologist Julian Huxley, in 1958, and refers to a monophyletic group; i.e., one that contains an organism and all the descendants of the possibly hypothetical closest common ancestor of all the members of the group. See monophyletic group, and cf. paraphyletic, and polyphyletic groups.
  • cladogram (KLAAD-oh-grahm) — a diagram derived from phylogenetic analysis illustrating evolutionary relationships between groups.
  • claval suture: the suture in the front wing of Hemiptera and Homoptera between the clavus and corium.
  • clavate (KLAY-vt): L. clava = club, cudgel; zool. — clubbed, club shaped, toward the tip.
  • clavus: the portion of the front wing in Hemiptera and Homoptera between the clavus and corium.
  • clasping spine: 1. arach. — an enlarged curved spine that articulates against the leg segment, as in the Mysmenidae, and that is used as a mating spur.
  • claw — see tarsal claw.
  • claw dentition: 1 arach. — the pectinate (i.e., like a comb) ventral surface of most claws, arranged in either a single (uniserial) or double (biserial) row of teeth.
  • claw tuft — a dense brush of hairs between the paired tarsal claws, and by its presence nearly always signals the absence of the unpaired claw; these tufts may be composed of simple hairs or thick broad one (= tenent hairs).
  • clypeus (KLYP-ee-uhs): L. clypeus = a shield; 1. arach. — the space between the anterior edge of the carapace and the anterior eyes; a sclerite on the face between the frons and the labrum;
  • cochlea (KAWK-lee-uh) (= stretcher): L. cochlea = snail, snail shell, spiral, spoon; 1. arach. — a pit at the tip of the epigynal scape, as exhibited by some species in the Linyphiidae family.
  • cocoon: a silken case in which the pupa is formed.
  • collophore: a small tubular structure on the entral side of the first abdominal segment in Collembola.
  • colulate (KAWL-yoo-late): 1. arach. — having a colulus.
  • colulus (KAWL-yoo-luhs): 1. arach. — a non-functional cribellum that may be as large as a cribellum but is more commonly reduced to a small fleshy lobe or a pair of setae.
  • compound eye: an eye composed or many individual elements, each of which s marked eternally by a facet; the facets are usually more or less hexagonal in shape;
  • compressed: flattened from side to side.
  • concolorous (kawn-KO-lor-uhs): 1. arach. — exhibiting a uniform coloration, generally in the context of several proximal characters being described at once.
  • conductor: 1. arach. — the structure of the male palp that is associated with the embolus.
  • corium: the basal, usually thickened part of the front wing in Hemiptera;
  • cornicle: one of a pair of elongate processes located dorsally ner the apex of abdomen in aphids;
  • costa: a longitudinal vein, usually forming the front margin of the wing; the costal area of the wing: that part just behind the ront margin; costal break: a point on costa where the vein appears broken or weakened; costal margin of wing: the front margin;
  • coxa (KAWX-uh) (pl. coxae): L. coxa = the hip bone; 1. zool. — the basal, or first attachment of a leg to the body; the basal leg segment; closed coxal cavities (front, Coleoptera), bounded posterioirly by a prothroacic sclerite; open coxal cavities (front, Coleoptera), bounded posteriorly by a mesothoracic sclerite.
  • cribellate (KRIB-uh-let): 1. arach. — having a cribellum.
  • cribellum (kree-BELL-uhm): L. cribellum = a sieve, a little sieve; 1. arach. — a broad, flat, spinning plate positioned anteriorly to the spinnerets of cribellate spiders; the cribellum is considered a homologous structure to the anterior median spinnerets (AMS).
  • crochets: tiny hooks on the prolegs of a caterpillar.
  • cross vein: a vein connecting adjacent longitudinal veins in an insect wing; antenodal cross veins, those just behind the front edge of the wing between base and nodus, extending from C to R (Odonata); discal cross vein, one just behind discal cell (Diptera); humeral cross vein, one in basal part of wing between C and Sc; medial cross vein, one connecting two branches of M; mediocubital cross vein, one connecting M and Cu; radial cross vein, one just behind R1; sectorial cross vein, one connecting two branches of Rs.
  • ctenidia (tenn-ID-ee-uh): Gr. κτενος “ctenos” = a comb; 1. arach. — a short process, on the male palpal tibia of some members of the Dictynidae family, that bear diminutive, stout, spines.
  • cubital intercalaries: longitudinal veins in distal part of wing between Cu1 and Cu2 (Ephemeroptera).
  • cubitus: the longitudinal vein just behind M.
  • cuneus: a more or less triangular apical piece of the corium, set off from the rest of the corium (Hemiptera).
  • cymbium (SEM-be-uhm); Gr. κυμβιον = small cup, small boat; 1. arach. — the palpal tarsus of the adult male, particularly that containing the palpal bulb, when modified into a cup or spoon shaped structure.



anat. = anatomy; arach. = arachnid; behav. = behavioral; biol. = biological (inclusive of all animals and plants); bot. = botanical (inclusive of all plants); Gr. = Greek; L. = Latin; q.v. = L. quod vide = which see; pl. = plural; taxon. = taxonomy; zool. = zoological (inclusive of all animals).


  1. Allaby, Michael, Ed. 1991. The Concise Oxford Dictionary of Zoology. Oxford Press.
  2. Beccaloni, Jan. 2009. Arachnids; Glossary, p. 319. University of California Press, p. 56.
  3. Borror, Donald J. 1970. Peterson Field Guides: Insects. Houghton Mifflin.
  4. Gertsch, Willis J., 1979. American Spiders, 2nd Edition: Glossary, pp. 255-260. Von Nostrand Reinhold Company.
  5. Howell, W. Mike, and Ronald L. Jenkins. 2004. Spiders of the Eastern United States; Glossary, Chapter X, pp. 341-348. Pearson Education.
  6. Jackman, John A. 1997. A Field Guide to Spiders & Scorpions of Texas: Glossary pp. 173-177. Texas Monthly.
  7. Kaston, B. J. 1978. How to know the spiders: Index and Pictured Glossary, pp. 267-272. McGraw Hill Company.
  8. Preston-Mafham, Rod. 1996. The Book of Spiders and Scorpions; Glossary, pp. 140-141. Barnes & Noble Books, New York.
  9. Ubick, D., P. Paquin, P.E. Cusing and V. Roth, editors, 2005. Spiders of North America, Chapter 72: Glossary — pronunciation guide. Published by the American Arachnological Society.
  10. Venes, Donald, Ed. 2009. Taber’s Cyclopedic Medical Dictionary, 21st Ed. F.A. Davis Company, Philadelphia.
  11. Williams, Tim. 2005. A Dictionary of the Roots and Combining Forms of Scientific Words. Squirrox Press, Norfolk, England.

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