Usually used to describe a small secondary structure. For example an accessory flagellum refers to a small flagellum attached to the antenna, or an accessory hook often refers to a small hook protruding from a larger anal hook.
the last abdominal "segment" in larval Diptera (that actually consists of several segments).
A false leg like appendage bearing a hook, located on the last segment of the abdomen, usually paired. Occasionally the hook may have a second accessory hook and/or ventral teeth.
before the apex, ie. anteapical claws have the claw inserted basal to the tip of the tarsus.
Paired segmental appendages, with one on each side of the head, functioning as sense organs. Plural form is antennae.
adjective for a feature on the sides of the anterior (front) part of a structure; there are many other such combined-positioned adjectives.
fungus, algae, and bacteria that forms a slippery, inconspicuous film over rocks and other substrates.
a ridge, or keel. Plural form is carinae. [image]
tail, when there is only one, or the middle tail when there are three (the other two being cerci).
region of the outer body with specialized cells to extract ions from the water; usually indistinguishable visually, but defined in some caddisfly larvae by a fine dark line surrounding the margins.
in Hemiptera, a large furrow on the forewing separating the clavas (posterior when the wings are spread) and the ebolium (anterior when the wings are spread).
in Hemiptera, when the wings are spread, it is the part of the wing posterior to the claval furrow; the wing minus the ebolium.
an organism that lives on plants or debris underwater with adaptations for moving along stems and roots.
An organism that attaches to surfaces in stream riffles; typically has adaptations (such as claws) or behaviors (like retreat construction) to live in these habitats.
the front part of an insect's head below the frons to which the labrum is attached anteriorly.
falling off at certain periods. For example, this term is used to describe the gills of nymphs in the family Heptageniidae (Ephemeroptera), which fall off easily when handled.
small tooth. [image]
an organism that swims by rowing with its hind legs in lentic and lotic habitats; typically comes to surface of water for oxygen.
any line where sclerites of the exoskeleton will separate during the molting process. These are found mostly on the midline of the top or underside of the head and on the midline of the top of the thorax.
in Hemiptera, when the wings are spread, it is the part of the wing anterior to the claval furrow. If the wings are closed, it is the part of the wings nearest the lateral margin, not including the clavus.
insects that feed by sifting suspended organic matter (including detritus, diatoms, algae, and sometimes meiofauna), from the water.
a part of a propleuron of a caddisfly that projects forward from the base of a foreleg.
In mayflies of the family Ephemeridae, when looking dorsally, a cuticular lobe projecting forward from the anteriormost margin of the face.
the face or front middle region of the head, usually defined by a pair of curved lines extending forward from the anterior end of the median dorsal ecdysial line.
respiratory organ; an extension of the body wall with many tracheae, variously either single and thread-like, multi-branched, flat, forked, etc.
part of the mouth parts/labrum, pair of lobes used much like a tongue. Smaller, and just inside of paraglossae. See image. [image]
in prognathous insects, the fused lower ends of the postocciput forming a plate on the underside of the insect's head.
a type of insect where the life cycle includes egg, larval, and adult stages, but lacks a pupal stage.
looking at a Simuliid larva, this refers to the small teeth between the larger teeth on the hypostoma
where the membranous tissue bubbles up to fill the space between segments. In some caddisfly larvae this looks like a “fat roll.”
extendable mask-like mouth part of a dragonfly or damselfly nymph, used to capture prey.
lower lip. [image]
upper lip, touching the clypeus in front of the mouth. [image]
inside edge of maxilla. [image]
accumulations of leaves and other coarse particulate matter in front of or behind obstructions in the water flow, such as logs.
zone of a standing body of water where fine sediments from shallower parts of the lake mix with organic matter from deeper reaches of the lake.
running-water pools and margins with fine sediments, some vascular plants growing in those sediments, and leaf litter forming the majority of detritus.
running-water riffles with coarse sediments, some plants growing in those coarse sediments, and leaf packs and woody debris serving as the majority of detritus.
part of the base of the labium, also referred to as the anterior ventral apotome. [image]
the second or middle thoracic segment bearing the midlegs and the forewings or forewing pads.
the third or hind thoracic segment bearing the hind legs and the hind wings or hind wing pads.
roughened grinding area at base of each mandible of some insects. [image]
a hard plate on the top of a thoracic segment of an insect or other arthropod. Plural form is nota.
in adult insects, a simple eye consisting of a single beadlike lens; in holometabolous larvae, simple eyes that make up the lateral eye-groups (also referred to as stemma). Plural form is ocelli.
a gill that covers the gill(s) on the next segment(s); usually these types of gills are flat and positioned on the dorsal (top) side of the abdomen.
like the palm of the hand with processes stemming from a singular point, used in reference to gill venation.
The paired and segmented appendages around the mouth arising from maxillae (one palp on each maxilla) and the labium (one pair); maxillary palps are the larger pair. Plural form is palps. See also palpus. [image]
The paired and segmented appendages around the mouth arising from maxillae (one palpus on each maxilla) and the labium (one pair); maxillary palpi are the larger pair. Plural form is palpi. See also palp.
part of the mouth parts/ labrum, pair of lobes used much like a tongue. Larger and just outside of glossae. See image. [image]
looking at a Simuliid larva, as you move away from the center of the hypostoma, paralateral teeth refers to any smaller teeth just beyond the large lateral teeth.
this is the knee, the leg segment found between the femora and tibia in some insects, but is usually absent.
style of flight seen in some Odonates, where the dragonfly frequently lands and rests (perches) during flight.
fungus, algae, and bacteria that forms a slippery, inconspicuous film over rocks and other substrates.
stalk-like, narrow, long and skinny. [image]
thin film of air permanently held on the surface of the body by a dense pile of microscopic spines.
further back in position; of or near the rear or hind end, especially of the body or a part of it.
posterior sclerite(s) on the underside of the head behind the prementum, sometimes divided into an anterior mentum and posterior submentum.
anterior sclerite on the underside of the head supporting labial palps, glossae and paraglossae; also called labiostipites. [image]
fleshy unsegmented nub, often paired, used for movement (e.g., on the abdomen of most caterpillars and some flies; on the thorax of some fly larvae).
the first or anterior thoracic segment bearing the anterior legs (but no wings or wing pads).
fast-flowing, turbulent water flowing over rocks or other solid objects on the stream bottom.
an adjective describing anything of, adjacent to, or living on the bank of a river, lake, pond, etc.
beak, or elongate mouth part as in Coleoptera: Curculionidae (Weevels) or Hemiptera (true bugs).
sa1, sa2, sa3
sa = setal area of a thoracic or abdominal segment, often marked by a sclerite or patch of setae--See image.
in Hemiptera, the triangular part of the mesothorax placed between the bases of the hemelytra, but in some groups partially or fully overlapping them.
An animal that cuts or tears larger pieces of organic matter (>10μ3 = greater than 10 cubic microns) into smaller, ingestible pieces (<10μ3 = less than 10 cubic microns). A micron is 1/1000 of a millimeter.
a style of flight seen in some Odonates where the dragonfly skims along the surface of the water, or more generally, they don't land frequently and seem to constantly be in flight while hunting.
an underwater tree stump or branch projecting in the water that may impede suspended objects (e.g., leaves) or serve as habitat for plants or animals.
small tube-shaped appendage that exudes silk threads, especially seen in spiders and larval Trichoptera and Lepidoptera. In larvae, this is typically located on the labium (lower lip) of an individual. [image]
In amphipneustic and metapneustic Diptera larvae, disclike area with respiratory openings on the last segment.
live on the surface of submerged objects or sediment; adapted to keep sediment off of themselves and remain on top of the substrate.
simple eyes that make up the lateral eye-groups in holometabolous larvae. Plural form is stemmata. Similar to ocelli, but in clusters of more than 3; usually present in larvae of holomotabolus insects.
simple eyes, similar to ocelli, but in clusters of more than 3; usually present in larvae of holomotabolus insects.
the second segment of the maxillae (second set of jaws). The lacinia, galea, and maxillary palps arise from the stipes.
a fine impressed line running lengthwise over the elytra of adult Coleoptera. Plural form is striae.
also known as a dun (common name). A life stage unique to the Ephemeroptera; a developmental stage between larval and adult stages in which the wings have developed but the genitalia have not. In this stage the wings appear clouded (unlike the glossy appearance in the adults). The mayflies leave the water as subimagos, fly to a safe location, and then molt one more time to become an adult.
groove with purely functional origin; i.e., any other groove on the body that is not a suture, such as those used for ecdysis or muscle attachment. Plural form is sulci.
organisms that are adapted to fishlike swimming; often cling to submerged objects and plants between bursts of swimming.
the number of tarsal segments of each leg pair listed in order; ie. # of tarsal segments of foreleg, middle leg, hind leg.
foot, most distal leg region (last part of a leg before the claw), often divided into subsegments. Plural form is tarsi.
tibia, shin or calf - not counting the claw, this is the second-most distal segment of the leg, proximal to the tarsus. Plural form is tibiae.
internal tubes filled with air that the insect uses for breathing. Sometimes visible through the gills of aquatic insects, vein-like in appearance.
hard structure on front of base of front leg of a caddisfly, usually more or less triangular and pointed apically, sometimes forked or hatchet-shaped.
in larval Coleoptera, paired processes extending from the end of the ninth abdominal tergum that are either jointed and moveable with muscles, or unjointed and immovable. Plural form is urogomphi.
triangular or rectangular sclerite between the genae on the ventral side of the head capsule of some caddisflies; sometimes divided by a single ventral ecdysal line where the genae meet in the middle, creating two smaller apotomes on either end of the suture, the anterior and posterior apotomes. [image]
undeveloped and encased wings located behind the thorax of hemimetabolous insect nymphs, including mayflies, stoneflies, true bugs, and dragonflies.