2 a b c d e f g h i l m p s t v


  • 2-4-2 eye pattern: arrangement of eyes in agelenid spiders (in this tool only in Hololena), eye rows are curved in a forward direction so strongly that the posterior lateral eyes are in the same horizontal alignment as the anterior median eyes such that it appears that there are 3 rows of eyes, 2 in the bottom and top rows and 4 in the middle (drawing, photo)


  • abdomen: major posterior body section (drawing)
  • AER: abbreviation for anterior eye row (drawing)
  • AME: abbreviation for anterior median eyes (drawing)
  • amorphous: in regard to egg sacs, having no easily determinable form
  • angular: in regard to egg sacs, having margins that have sharp angles, like in a triangle, not round or smooth
  • anterior: toward the front of the body (drawing)
  • anterior eye row: front 4 eyes, usually arranged in a straight or slightly curved line, abbreviated AER (drawing)
  • anterior median eyes: within the anterior eye row, the 2 eyes in the middle, closest to each other, abbreviated AER (drawing)
  • apophysis: prominence emerging from a body part, typically involving the genitalia (drawing, photo)


  • bulbous: a bulb-like object; a swollen, round, or bulging object. In Thiodina hespera, the base of the spines on the ventral surface of tibia I are bulbous, which is a diagnostic feature, always in 2 pairs and swollen at the base


  • carapace: dorsal portion of the cephalothorax (drawing, photo)
  • cardiac region: longitudinal region on the dorsal anterior portion of the abdomen that is sometimes a different color than the rest of the abdomen due to thin skin; a region where special markings can occur (drawing, photo)
  • cephalic region: area on the carapace which includes the eyes and the space immediately behind it (drawing, photo)
  • cephalothorax: major anterior body section to which the legs attach (drawing)
  • chelicera: (plural = chelicerae) movable mouthpart to which the fang is attached (drawing, photo)
  • clypeus: the portion of the face of the spider between the chelicerae and the eyes (drawing, photo)
  • coffee bean pattern: on the dorsal abdominal surface of Neoscona oaxacensis, there are spines that run down the middle of yellow oblong spots, giving the impression of many coffee beans on the back of the spider (photo)
  • coxa: first of the 7 leg segments, the segment closest to the cephalothorax (drawing, photo)


  • distal: on appendages, in a direction further away from the central body (drawing)
  • dorsal: view from the top portion of the body (drawing)


  • elongate: in regard to the abdomen, longer than thick, usually about 2 to 3 times longer than its thickness
  • epigynum: female genitalia covering, typically sclerotized (drawing, photo)
  • exoskeleton: external covering of the body that provides support for internal muscles and organs, shed as a complete unit and left behind as the spider grows into the next instar


  • fang: venom delivery structure on the distal end of the chelicera (drawing)
  • femur: (plural = femora) third of the 7 leg segments, the long segment closest to the body, between the trochanter and patella (drawing, photo)


  • globose: regarding the abdomen, rounded like a globe as in black widow spiders (drawing, photo)


  • hexagon + 2: the eye pattern in Oxyopes spiders where six of the eyes are arranged in a hexagon on the top of the carapace with two small eyes ventral to the hexagon (drawing, photo)


  • instar: stage between moltings; spiders go through several instars prior to maturity


  • lateral: away from the midline of the body (drawing)
  • longitudinal: in line with the body, in an anterior to posterior direction


  • palp: abbreviated term for pedipalp (drawing, photo)
  • patella: fourth of 7 leg segments, typically small, and between femur and tibia (drawing, photo)
  • pedipalp: leg-like segment on the anterior portion of the body, composed of 6 segments (compared to the leg, it is missing the metatarsus), undifferentiated in the female and most immatures, swollen and undifferentiated in penultimate males, contains the male reproductive structures in mature males (drawing, photo)
  • penultimate: instar before the mature molt; in penultimate males, the tarsus of the pedipalp is swollen but has no diagnostic characteristics that aid identification
  • PER: abbreviation for posterior eye row (drawing)
  • PLE: abbreviation for posterior median eyes (drawing)
  • PME: abbreviation for posterior median eyes (drawing)
  • posterior: toward the rear of the body (drawing)
  • posterior eye row: rear 4 eyes, usually arranged in a straight or slightly curved line, but sometimes can be so greatly curved that they are designated as being in 2 rows; abbreviated PER (drawing)
  • posterior lateral eyes: within the posterior eye row, the 2 eyes on the ends of the row, abbreviated PLE (drawing)
  • posterior median eyes: within the posterior eye row, the 2 eyes in the middle, closest to each other, abbreviated PME (drawing)
  • proximal: on appendages, in a direction toward the central body (drawing)


  • sclerotized: hardened composition of a bodily structure, similar to how a human fingernail is hard in comparison to the surrounding skin
  • seta: (plural = setae) hair-like appendages common on legs and body, sometimes morphologically specialized (photo)
  • spine: conspicuous, robust, elongate, tapered, and pointed prominence found on legs of some species, sometimes diagnostic (photo)
  • spinnerets: specialized organs at the posterior-most portion of the abdomen from which silk is emitted; the number of segments or shape of the spinnerets is diagnostic for some species (drawing, photo)
  • subequal: similar in size, typically in reference to eyes (drawing, photo)
  • suspended: in regard to egg sacs, when the sac is attached to the web by silk strands and is hanging in space, as opposed to egg sacs that are attached to a substrate


  • tarsus: (plural = tarsi) seventh of 7 leg segments, at distal end of leg after the metatarsus (drawing, photo)
  • tibia: fifth of 7 leg segments, long segment between the patella and metatarsus (drawing, photo)
  • trochanter: second of 7 leg segments, very small segment between coxa and femur; must view spider from ventral aspect and bend the femur to see it


  • ventral: (also: venter) bottom facing surface of the spider or its palp (drawing)