Parameres ('side parts') are part of the external reproductive organs of male insects and the term was first used by Verhoeff in 1893 for the lateral genital lobes in

Coleoptera Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

. The primary phallic lobes which appear in the nymph or larval stages may become a pair of penes in the Ephemeroptera or a simple median penis in the

Thysanura Thysanura is the now Deprecation, deprecated name of what was, for over a century, recognised as an Order (biology), order in the Class (biology), class Insecta. The two constituent groups within the former order, the Archaeognatha (jumping bristle ...

. In higher insect orders from

Orthoptera Orthoptera () is an order of insects that comprises the grasshoppers, locusts, and crickets, including closely related insects, such as the bush crickets or katydids and wētā. The order is subdivided into two suborders: Caelifera – gras ...

Hymenoptera Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are parasitic. Females typi ...

, each of the primary lobes is divided into two secondary lobes or phallomeres, termed parameres and mesomeres (NB: this use of the term "mesomere" is not to be confused with the same term in segmentation

embryology Embryology (from Ancient Greek, Greek ἔμβρυον, ''embryon'', "the unborn, embryo"; and -λογία, ''-logy, -logia'') is the branch of animal biology that studies the Prenatal development (biology), prenatal development of gametes (sex ...

.) In adult insects parameres may elongate and become genital

claspers In biology, a clasper is a male anatomical structure found in some groups of animals, used in mating. Male cartilaginous fish have claspers formed from the posterior portion of their pelvic fin which serve to channel semen into the female's c ...

. These claspers may themselves occur in two segments, forming a

proximal Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

basimere and a

distal Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provi ...

telomere A telomere (; ) is a region of repetitive nucleotide sequences associated with specialized proteins at the ends of linear chromosomes (see #Sequences, Sequences). Telomeres are a widespread genetic feature most commonly found in eukaryotes. In ...

or harpago ('grappling hook'). A Revised Interpretation of the External Reproductive Organs of Male Insects - R. E. Snodgrass
/ref> The morphology of insect genitalia displays enormous diversity and consequently has become of prime importance in taxonomy or the classification of insects by their affinities.

References

{{reflist Insect morphology Animal reproductive system