''Arenivaga'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of sand cockroaches, of the subfamily Corydiinae, in the family

Corydiidae Corydiidae, previously known as Polyphagidae, is a family of the order Blattodea ( cockroaches). Many are known as sand cockroaches. The family is divided into five subfamilies, comprising some 40 genera. One prominent species is the desert cockr ...

. These cockroaches live in sandy soils and dunes in the southwestern United States, Florida and Mexico. ''Arenivaga'' comes from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

''arena'' meaning ''sand'' and ''vagus'' meaning ''wandering''.

Characteristics

This genus is

sexually dimorphic Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

, with males and females differing in morphology. The insects are dorso-ventrally flattened and males have wings that are generally longer than the abdomen. The colour cannot be relied on to distinguish between species because the insects sequester pigments from their food and therefore their colour depends on their diet; they accumulate

uric acid Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula C5H4N4O3. It forms ions and salts known as urates and acid urates, such as ammonium acid urate. Uric acid is a product of the metabolic breakdown ...

in varying amounts, and this also affects their appearance. The head has a pair of long, slender antennae, two large compound eyes and two protuberant

ocelli A simple eye (sometimes called a pigment pit) refers to a form of eye or an optical arrangement composed of a single lens and without an elaborate retina such as occurs in most vertebrates. In this sense "simple eye" is distinct from a multi-le ...

. The labrum is broad, and the frons and the hinder part of the clypeus are fused and form a bulge in a manner unusual for cockroaches. The

pronotum The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum ( dorsal), the prosternum ( ventral), and the propleuron ( lateral) o ...

is large and covers the head and extends sideways to about the width of the body. There are

seta In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. T ...

e on the dorsal surface of the pronotum and different species have different patterning, which may be impressed into the surface. The patterning may be surrounded by an aura which radiates out from the pattern, and at the side of the pronotum, uric acid may be stored in white or pale pink patches. The smallest species is '' A. pumila'' at a length of , and the largest '' A. bolliana'' at . Some species are broader and more robust than others. The legs bear many spines, including spines around the joint between the meso and meta-tibia, and the tarsi have two claws, except in '' A. darwini'' where there is only one. The main means of distinguishing between the different species is close examination of the male genitalia.

Ecology

Females and nymphs live underground, "swimming" through the sandy

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (locomotion), the surface over which an organism lo ...

, and residing in the burrows of small mammals with which they cohabit. They feed on

mycorrhizal fungi A mycorrhiza (from Greek μύκης ', "fungus", and ῥίζα ', "root"; pl. mycorrhizae, mycorrhiza or mycorrhizas) is a symbiotic association between a fungus and a plant. The term mycorrhiza refers to the role of the fungus in the plan ...

, plant detritus, and the seeds gathered by the mammals. Males have brief lives and live mostly on the surface. The breeding habits of sand cockroaches have been little studied but it seems that females emerge onto the surface at night, attract the winged males, perhaps by the use of

pheromone A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...

s, mate and rebury themselves in the sand. The desert cockroach (''A. investigata'') has been shown to be able to absorb water from the atmosphere.

References

{{Taxonbar, from=Q4668230 Cockroach genera