Glossary

acidopore: A small hole at the tip of the gaster through which formic acid and pheromones are released. The hole is surrounded by a characteristic fringe of hairs. The structure is present in, and only in, ants of the subfamily Formicinae.

acuminate: Tapering gradually to a sharp point. Applied to erect hairs in Antkey.

alate: Refers to the winged lifestage of an ant. Males are generally all alate. Queens are generally alate prior to mating. See also: dealate

antenna: (pl. antennae) In Antkey species, the antenna consists of an elongate basal segment (the scape) followed distally by 5–11 shorter segments (the funiculus). The 1-4 terminal segments might be enlarged (antennal club)

antennal club: The more or less enlarged apical segments of a clubbed antenna. Most antennal clubs of ant species are composed of 2-3 segments, though some species in Antkey have a 1-segmented clubs or 4-segmented clubs.

antennal club, three-segmented: The three terminal segments of the funiculus are enlarged relative to the other segments.

antennal club, two-segmented: The two terminal segments of the funiculus that are enlarged relative to the other segments.

antennal ridge: A raised and distinct carina surrounding the antennal socket.

antennal scape: The first, elongated segment of the antennae that attaches to the head.

antennal scape length: The maximum straight-line length of the scape, excluding the basal constriction or neck that occurs just distal of the condylar bulb.

antennal scrobe: A groove recessed in the head to receive all or a portion of the antennal scape. Often margined by the frontal carinae.

anterior: Towards the front (i.e. head or mandibles) of the specimen. Opposite of posterior.

apical: At, near or pertaining to the apex (farthest from the body) of any structure. [Torre-Beuno Glossary]

appressed hair: Refers to hairs that lie on the body surface, thus parallel, or nearly so, to that surface. [Antwiki.org]

basal: At or pertaining to the base or point of attachment or nearest the main body. [Torre-Beuno Glossary]

bicolored: Two different colors.

bimorphic: Refers to species in which the workers are differentiated into subcastes of different sizes. In bimorphic castes (such as many Pheidole species) the workers develop into one of two discrete sizes (large or small). See also polymorphic and monomorphic.

carina: (pl. carinae) A ridge or low, keel-like crest. [Antwiki.org]

caste: Any set of individuals in a given colony that is both morphologically distinct and specialized in behavior.

clypeus: In full face view, the broad shield that forms the anterior portion of the ant's head. The anterior clypeal margin usually forms the anterior margin of the head. The posterior clypeal margin usually borders the antennal sockets and frontal carinae or frontal lobes, or may project backwards between them.

clypeus, middle tooth absent: The character state observed in Solenopsis geminata where the anterior margin of the clypeus lacks a middle (median) tooth, but possesses one pair of teeth that straddles the median.

clypeus, middle tooth present: The character state observed in Solenopsis invicta where the anterior margin of the clypeus is armed with one tooth in the middle (median) and one pair of side (lateral) teeth. The middle tooth is usually smaller than the side teeth, and the proper viewing angle is required for acurate assessment. The middle tooth tends to be more easily observed in smaller workers than in larger workers.

color: color uniformly brownish yellow (Monomorium) The entire body is uniformly brownish yellow. Used in Antkey to separate Monomorium pharaonis from all other Monomorium species.

concolorous: uniform in color

congeners: Other species belonging to the same genus.

dealate: Generally refers to the lifestage of a queen that has shed her wings, usually after having mated. See also: alate

Dolichoderinae: A subfamily of ants with one waist segment (petiole), and with the gaster armed only with a ventral slit. Some of the more notorious invasive ants in this subfamily include Linepithema humile, Tapinoma melanocephalum, and several species related to Technomyrmex albipes.

dorsal: On or of the functionally upper surface.

dorsal view: The view of a specimen achieved by looking directly at its dorsal surface.

erect hairs: Refers to a hair that stands straight up, or nearly so, from the body surface. [Antwiki.org]

eye: In Antkey generally refers to the compound eyes located at or near the lateral margin of the face. If present, it is composed of one to many individual facets.

eyes break outline of head: When examining the specimen in full face view, the eyes interrupt the the continuous curve of the head's margin.

eyes within outline of head: When examining the specimen in full face view, the eyes do not interrupt the continuous curve of the head's margin. Dolichoderinae, in addition to several Formicinae, exhibit this character.

flagellate: See flagellate pilosity.

flexuous: Bending or winding alternately from side to side; sinuous; flexible.

Formicinae: A subfamily of ants characterized by a single waist segment (petiole) and with the gaster armed with an acidopore. Some of the more notorious invasive ants in this subfamily include Anoplolepis gracilipes, Paratrechina longicornis, and Paratrechina vaga.

frontal carina: A pair of longitudinal ridges extending between the antennal sockets from the clypeus towards the posterior head margin. They are very variable in length and strength of development, but often form the upper antennal scrobe margin.

frontal lobes: The frontal carinae expanded into laterally projecting lobes which overhang and partially to entirely conceal the antennal sockets. In Antkey, absent in Amblyoponinae and Cerapachyinae.

FRS (distance between frontal carinae): The distance between frontal carinae. Used by Seifert (2003) to separate different species of Cardiocondyla.

funiculus: Composed of all the small antennal segments distal to the antennal scape.

gaster: Refers to the posterior-most body part that forms the apparent abdomen. Morphologically the gaster consists of abdominal segments 3–7 or 4-7 depending on whether there is a postpetiole.

hairs: In Antkey, hairs are generally either referred to as erect hairs or pubescence. Used for both generic and species level diagnosis.

head length: The maximum distance from the mid-point of the anterior clypeal margin to the midpoint of the posterior margin of head, measured in full-face view. Impressions on anterior clypeal margin and posterior head margin do not reduce head length.

head ovoid: The head is ovoid with the head width distinctly greater than head width. Used in Antkey to separate Camponotus from Plagiolepis.

head shape, triangular: In full face view, the posterior margin of the head is significantly wider than the anterior margin.

head width: The maximum width of the head that can be measured in full face view.

head, posterior margin: The margin of the head that is farthest away from the mandibles.

lateral: Relating, pertaining, or attached, to the side.

legs: Leg parts referred to in Antkey include the coxa, femur, tarsus and pretarsal claws.

mandibles: The jaws which are used by ants to take, manipulate and chew food resources. They are extremely variable in shape, size and dentition, and have great importance in ant taxonomy.

mandibles, linear: Mandibles that are modified into long thin blades for specialized hunting, often with a fork of teeth at the end. Ants bearing linear mandibles are sometimes referred to as trap-jaw ants because suitable prey will trigger the mandibles to snap closed with incredible force. 

mandibles, triangular: Mandibles that are approximately triangular in shape. This is the most common shape of most ant mandibles.

median: In or at the middle; of or pertaining to the middle; along the midline of the body.

mesonotum: The tergite of the mesosoma posterior to the pronotum. If the two are fused, they are together referred to as the promesonotum.

mesopleuron: The pleuron (lateral sclerite) of the mesothorax. It may be a single sclerite or divided into an upper anepisternum and lower katepisternum.

mesosoma: (= alitrunk, = apparent thorax) A convenience term for the second visible main section of an ant’s body, between the head and the gaster. Sometimes referred to (incorrectly) as the 'alitrunk' or 'thorax'.

mesosoma, gradually sloped: A character state observed in myrmicine genera such as Cardiocondyla and Tetramorium in which the mesosoma is nearly flat and descends at a very gradual angle.

mesosoma, steeply sloped: A character state observed in the myrmicine genus such as Pheidole in which the mesosoma appears humped and descends at a sharp angle.

metanotum, impressed: In profile and dorsal view, the region between the mesonotum and propodeum is indented.

metanotum, not impressed: In profile and dorsal view, the region between the mesonotum and propodeum is not indented, but forms a continuous and uninterupted curve.

monodomous: All ants in a colony inhabit a single nest.

monogynous: A single reproductive queen present in a colony.

monomorphic: All workers within the colony are approximately the same shape and size.

Myrmicinae: A subfamily of ants characterized by the presence of two waist segments (petiole, postpetiole) and with the gaster armed with a sting. Some of the more notorious invasive ants in this subfamily include Solenopsis invicta, Pheidole megacephala, and Wasmannia auropunctata.

ocellus: (pl. ocelli) A maximum of three simple, single-faceted eyes, which when present (absent in many worker ant taxa) are located in a triangle on the cephalic dorsum. Morphologically the anterior ocellus marks the posterior limit of the frons, and the posterior pair are on the vertex. [Antwiki.org]

pectinate: With many fine teeth, comb-like.

petiolar node: The raised portion of the petiole between the petiolar peduncle and the gaster.

petiolar node, rounded: The shape of petiolar nodes that are evenly rounded and without distinct anterior, posterior or dorsal faces. Tetramorium lanuginosum and T. tonganum have rounded petiolar nodes.

petiolar node, square-shaped: The shape of petiolar nodes with distinct anterior, posterior and dorsal faces. Species with square-shaped petiolar nodes include Tetramorium biacrinatum, T. simillimum, and Wasmannia auropunctata.

petiolar node, wave-shaped: The shape of petiolar nodes with the anterior and dorsal faces rounded together and a distinct posterior face. Species with wave-shaped petiolar nodes include Tetramorium insolens and T. pacificum.

petiolar peduncle: The stem connecting the petiolar node to the propodeum.

petiole: The waist segment separating the mesosoma from either the gaster or the postpetiole.

pilosity: A general term for hairs. Pilosity can be erect or appressed (close against the surface), long or short, thick or thin, light or dark. Paratrechina is often identified by characteristic pairs of long thick hairs arranged in rows. Strumigenys is known for highly modified flagellate and spatulate pilosity.

pilosity, flagellate: Hairs that are long, thin and whip-like, see Strumigenys godeffroyi.

pilosity, spatulate: Hairs that are flat and become wider towards the end like a spatula, examples, Pyramica and Strumigenys.

polydomous: When a single colony inhabits multiple nests.

polygynous: Multiple reproductive queens present in a single colony.

polymorphic: Refers to a worker caste which shows a large, continuous range in size from small to large workers.

Ponerinae: A subfamily of ants characterized by the presence of one waist segments (petiole) and with the gaster armed with a sting. Although few Ponerines are considered to be high-threat invasive species, species such as Odontomachus simillimus, Hypoponera opaciceps, and Pachycondyla stigma have spread throughout the Pacific Island area and beyond.

posterior: Hinder or hindmost, opposed to anterior; hind or rear.

posterolateral: Toward the rear and side.

posterolateral lobes: Refers to the posterior sides of the head that are strongly developed in the major workers of Pheidole. Although this region has been referred to as the occipital lobes in previous literature, the term is not as morphologically accurate.

postpetiole: The waist segment between the petiole and the gaster. Not present in all ants.

preapical teeth: Teeth that precede the apical teeth (those occurring at the tip) of the mandibles, see Strumigenys species.

pretarsal claw: See also: tarsus

profile: A view of the specimen achieved by looking directly at one side of the specimen.

pronotal spines: Distinct spines attached to the dorsal surface of the pronotum.

pronotum: The most anterior tergite of the mesosoma.

propodeal: See also: propodeum

propodeal declivity: The posterior face of the propodeum. Viewed in profile, it can be convex, flat or concave.

propodeal spines: A pair of spines projecting from the dorsal surface of the propodeum. The length of the spines can vary from long, (i.e. Wasmannia auropunctata) to short (i.e. Tetramorium simillimum), and can also vary within a species.

propodeal spiracle: An orifice (opening) located on the propodeum that is used for exchanging gases between the body of the ant and the atmosphere. The position, size and shape of the propodeal spiracle can be a good identification character.

propodeum: The posterior portion of the mesosoma, anterior to the waist.

pubescence: Short, appressed hairs that appear as a soft down and make the surface look dull.

punctate: Surface sculpture characterized by small shallow punctures, as if covered in pin pricks.

punctate sculpture: A rough surface created on the specimen resembling a multitude of pin pricks. In the field, a punctate sculpture can be identified by the dull, unreflecting appearance. Species of Monomorium, Cardiocondyla and Hypoponera afford good examples.

scape: See also: antennal scapes

scrobe: See also: antennal scrobe

sculpture: The markings or pattern of impressions or elevations on a surface (T-B).

setae: Longer, often erect hairs that differ from the shorter, appressed pubescence.

spatulate: See spatulate hairs.

spongiform: Specialized sponge-like external cuticular tissue, distributed mainly about the waist segments in some groups of ants. In Antkey the only ants with spongiform are in Strumigenys. See also: postpetiole with well developed spongiformwaist with spongiform

spongiform appendages: Sponge-like structures that occur on the body parts (particularly the propodeum and waist) of some ant species. Spongiform appendages are prevelant among ants in the tribe Dacetini, including the genera Pyramica and Strumigenys.

sting: The sting is located at the tip of the gaster and can be used both as a defense against predators and as a weapon against prey. It is often connected to an internal venom sac. Some species can retract their stings, making them appear absent.

synanthropic: Species of wild animals and plants of various kinds that live near, and benefit from, an association with humans and the somewhat artificial habitats that humans create around them.

tarsus: (pl. tarsi) Collective term for the five small apical subsegments (tarsomeres) of any leg. [Antwiki.org] See also: pretarsal claw

tibia: (pl. tibiae) The fourth segment of any leg, counting from the basal segment (coxa) that articulates with the thorax. At its apex the tibia frequently bears one or two tibial spurs. The tibia of the prothoracic (fore) leg is often termed the protibia, that of the mesothoracic (middle) leg the mesotibia, and that of the metathoracic (hind) leg the metatibia. [Antwiki.org]

tibial spine, pectinate: A spine at the end of the hind tibia that is modified into a comb structure. Both Hypoponera and Pachycondyla have a pectinate hind tibial spur, but only Pachycondyla has a simple hind tibial spur.

tibial spine, simple: A spine at the end of the hind tibia that is unmodified, and does not appear similar to a comb.This character can be used to separate Hypoponera (absent) from Pachycondyla (present). In order to obtain a view of the structure, it may be necessary to manipulate the specimen until a favorable perspective is achieved.

tibial spurs: One or two spurs located at the apex of the tibia just basal of the tarsus. May be simple or pectinate.

tubercles: Small knobby prominences or raised bumps. See also: first gastral segment with tubercles

waist: An informal collective term for the one or two isolated and reduced abdominal segments that occur between the mesosoma and gaster. When only the petiole (AII) is isolated the waist is said to be one-segmented, but in those taxa where the postpetiole (AIII) is also separated the waist is said to be two-segmented. [Antwiki.org]

worker caste: See also: caste

worker, major: A worker subcaste that is characterized by a larger size than other workers of the same colony. Major workers, sometimes referred to as soldiers, often exhibit disproportionately larger heads due to allometric growth. Genera that include species with a polymorphic worker caste include Pheidole, Solenopsis, Monomorium, and Camponotus. Also see minor worker.

worker, minor: A worker subcaste that is characterized by smaller size than other workers of the same colony. Minor workers, sometimes referred to simply as minors, are often proportionally similar to workers of monomorphic species. Genera within Antkey that include species with a polymorphic worker caste include Pheidole, Solenopsis, Monomorium and Camponotus. Also see major worker.