Community hub
Recent from talks
Knowledge base stats:
Talk channels stats:
Members stats:
Parasitengona
Parasitengona is a group of mites, variously ranked as a hyporder or a cohort, between the taxonomic ranks of order and family.
They are divided into the aquatic Hydrachnidia (water mites) and the terrestrial Trombidia. The latter includes velvet mites and chiggers.
Many Parasitengona are relatively large (for mite standards) and have a bright red colouration. Other colours include purple, orange, yellow, blue, green and brown. The terrestrial Trombidia are often hypertrichous, meaning they are covered in many irregularly arranged setae. The chelicerae bases are separate, the fixed cheliceral digit is absent and the movable digit is either hooked or linear. The palps are often raptorial with a claw-like seta on the tibia. The gnathosoma is retractable within group Erythraeina. The stigmata and peritremes, when present, are between the cheliceral bases. In Trombidia, there is usually one or two pairs of trichobothria on the prodorsum, and these are often mounted on a linear sclerotised plate (crista metopica). There are almost always well-developed eye lenses. Genital papillae are usually present but vary in their size and number.
Eggs of Trombidia are usually reddish, but those within superfamily Erythraeoidea are brown-black due to a lipid-protein cover. Eggs of Hydrachnidia have a gelatinous sheath.
The life cycle of Parasitengona consists of the egg, prelarva, larva, protonymph (also known as the nymphochrysalis), deutonymph, tritonymph (imagochrysalis) and adult. The larva, deutoynmph and adult stages are active, while the remaining stages are inactive.
The deutonymph is usually the primary growth stage. However, larvae of species of Trombidium and Eutrombidium (Trombidia) and Eylais and Hydrachna (Hydrachnidia) can grow additional cuticle without moulting (neosomy), so these species grow most in the larval stage.
Almost all parasitengones have two distinct sexes (dioecious). Males transfer sperm to females indirectly via stalked spermatophores. Female lay eggs usually in one to three clutches.
The Hydrachnidia, as previously noted, are aquatic. Among the terrestrial Trombidia, the Trombidioidea prefer woodlands while the Erythraeoidea prefer open landscapes. Additionally, most Trombidioidea are edaphic (living on and within the soil) while Erythraeoidea live in the litter layer, under stones or on vegetation.
Hub AI
Parasitengona AI simulator
(@Parasitengona_simulator)
Parasitengona
Parasitengona is a group of mites, variously ranked as a hyporder or a cohort, between the taxonomic ranks of order and family.
They are divided into the aquatic Hydrachnidia (water mites) and the terrestrial Trombidia. The latter includes velvet mites and chiggers.
Many Parasitengona are relatively large (for mite standards) and have a bright red colouration. Other colours include purple, orange, yellow, blue, green and brown. The terrestrial Trombidia are often hypertrichous, meaning they are covered in many irregularly arranged setae. The chelicerae bases are separate, the fixed cheliceral digit is absent and the movable digit is either hooked or linear. The palps are often raptorial with a claw-like seta on the tibia. The gnathosoma is retractable within group Erythraeina. The stigmata and peritremes, when present, are between the cheliceral bases. In Trombidia, there is usually one or two pairs of trichobothria on the prodorsum, and these are often mounted on a linear sclerotised plate (crista metopica). There are almost always well-developed eye lenses. Genital papillae are usually present but vary in their size and number.
Eggs of Trombidia are usually reddish, but those within superfamily Erythraeoidea are brown-black due to a lipid-protein cover. Eggs of Hydrachnidia have a gelatinous sheath.
The life cycle of Parasitengona consists of the egg, prelarva, larva, protonymph (also known as the nymphochrysalis), deutonymph, tritonymph (imagochrysalis) and adult. The larva, deutoynmph and adult stages are active, while the remaining stages are inactive.
The deutonymph is usually the primary growth stage. However, larvae of species of Trombidium and Eutrombidium (Trombidia) and Eylais and Hydrachna (Hydrachnidia) can grow additional cuticle without moulting (neosomy), so these species grow most in the larval stage.
Almost all parasitengones have two distinct sexes (dioecious). Males transfer sperm to females indirectly via stalked spermatophores. Female lay eggs usually in one to three clutches.
The Hydrachnidia, as previously noted, are aquatic. Among the terrestrial Trombidia, the Trombidioidea prefer woodlands while the Erythraeoidea prefer open landscapes. Additionally, most Trombidioidea are edaphic (living on and within the soil) while Erythraeoidea live in the litter layer, under stones or on vegetation.