Primitive-insects
Guides
Lepisma
silverfish
Lepisma is a genus of primitive wingless insects in the family Lepismatidae. The most familiar species is Lepisma saccharina, commonly known as the silverfish, which is a cosmopolitan commensal of humans. Members of this genus are characterized by their flattened, torpedo-shaped bodies, long antennae, and three caudal filaments. The genus name has neuter gender per ICZN Opinion 2427 (2018), affecting species epithet endings.
Lepismatidae
Typical Silverfishes
Lepismatidae is a family of primitive, wingless insects in the order Zygentoma, containing approximately 190-340 described species worldwide. The family includes the two most familiar domestic species: the silverfish (Lepisma saccharina) and the firebrat (Thermobia domestica). These ancient insects represent some of the earliest diverging lineages within Insecta, with origins dating back hundreds of millions of years. Members are characterized by elongated, flattened bodies covered in scales, three caudal filaments, and a complete absence of wings throughout their life cycle.
Leucolepisma
Leucolepisma is a monotypic genus of silverfish in the family Lepismatidae, established by Wall in 1954. The genus contains a single described species, Leucolepisma arenarium. Like other members of Zygentoma, these are wingless, primitive insects with elongated bodies and three terminal filaments. The genus is distinguished from related silverfish by specific morphological characteristics, though detailed documentation remains limited.
Machilidae
Jumping Bristletails
Machilidae is a family of wingless insects in the order Archaeognatha, commonly known as jumping bristletails. Adults measure 7–20 mm in body length, with elongated cylindrical bodies covered in overlapping scales and three long terminal filaments. They possess large contiguous compound eyes, a humped thorax, and enlarged hind legs that enable rapid jumping when disturbed. The family contains approximately 250–450 described species with a nearly cosmopolitan distribution, primarily associated with moist, sheltered microhabitats including rocky shorelines, leaf litter, and rock crevices.
Machilinus
rock bristletails
Machilinus is a genus of rock bristletails in the family Meinertellidae, comprising approximately 17 described species. These primitive wingless insects are distinguished from related genera by their diurnal activity pattern, in contrast to the nocturnal habits of many other bristletails. They occupy rocky microhabitats and represent one of the more derived lineages within the Archaeognatha.
Mesomachilis
jumping bristletails
Mesomachilis is a genus of jumping bristletails in the family Machilidae, first described by Silvestri in 1911. The genus contains approximately six described species distributed across North America, including the western United States, Canada, and Mexico. These primitive insects belong to the order Archaeognatha, one of the earliest diverging lineages of living insects.
Pedetontus
jumping bristletails
Pedetontus is a genus of jumping bristletails (order Archaeognatha) in the family Machilidae, first described by Silvestri in 1911. The genus contains approximately 10 described species, with additional cryptic diversity identified through molecular studies, particularly in China where 17 species have been documented. Species are wingless and retain numerous ancestral characteristics including monocondylous mandibles and well-developed abdominal appendages. Recent mitogenomic studies indicate that current morphological classification within the genus requires revision due to paraphyly and cryptic species complexes.
Pedetontus submutans
Pedetontus submutans is a species of jumping bristletail in the family Machilidae, first described by Silvestri in 1911. As a member of the order Archaeognatha, it represents one of the most primitive living lineages of insects. The species is documented from North America. Like other machilids, it is likely found in moist terrestrial microhabitats.
Stylifera
Stylifera is a genus of silverfish (order Zygentoma) in the family Lepismatidae, established by Stach in 1932. The genus contains at least two described species: Stylifera gigantea and Stylifera impudica, both described by Escherich in 1905. Silverfish in this family are wingless, primitive insects characterized by their elongated, flattened bodies and three terminal cerci. Members of the genus are rarely encountered in scientific literature, with most biological details remaining undocumented.