Allergen
Guides
Blastophaga
fig wasps
Blastophaga is a genus of minute wasps in the family Agaonidae that engage in obligate mutualism with Ficus fig trees, a coevolutionary relationship spanning at least 80 million years. Female wasps enter receptive figs (syconia) through specialized ostioles to lay eggs in flowers and transport pollen, enabling fig reproduction. The genus exhibits varying degrees of host specificity, with some species showing strict fidelity to particular Ficus species while others demonstrate host sharing across multiple varieties. Notable species include Blastophaga psenes, the exclusive pollinator of the common fig (Ficus carica), and Blastophaga javana, associated with Ficus hirta.
Blatta orientalis
Oriental Cockroach, Waterbug
Blatta orientalis is a large, dark-colored cockroach and a significant urban pest. Adult males measure 18–29 mm and females 20–27 mm. Females appear wingless but are brachypterous with non-functional wing pads; males have reduced wings that do not cover the abdomen. The species thrives in dark, damp environments such as basements, crawl spaces, and sewers. It is a major vector for pathogens including E. coli, Staphylococcus, and Salmonella, and proteins from this species can trigger allergic reactions and asthma.
Cladotanytarsus
Cladotanytarsus is a genus of non-biting midges (Chironomidae) containing over 80 described species with worldwide distribution, particularly diverse in the Holarctic region. The genus comprises two subgenera: Cladotanytarsus s. str. and Lenziella. Species are primarily lacustrine, with adults often associated with lake surroundings and larvae inhabiting freshwater sediments. Several species have been described from experimentally acidified lakes in North America, demonstrating tolerance to varying pH conditions. One species, C. lewisi, is a significant human allergen source in Sudan.
Holocnemus
cellar spiders
Holocnemus is a genus of cellar spiders (family Pholcidae) first described by Eugène Louis Simon in 1873. The genus is distinguished by dark marks on the leg femora and tibiae in both sexes, a trait shared with related genera Crossopriza, Stygopholcus, and Maghreba. As of October 2025, the genus comprises four species, with H. pluchei being the most widely distributed due to human-mediated introduction outside its native range.
Holocnemus pluchei
Marbled Cellar Spider
Holocnemus pluchei is a cellar spider native to the Mediterranean region that has been introduced to North America, Australia, and other regions. It is notable for its group-living behavior, with multiple individuals often sharing communal webs. Both sexes possess stridulatory organs, an unusual trait among spiders. The species exhibits a unique defensive behavior called 'bouncing' when disturbed. It has been identified as a source of allergenic proteins that can trigger asthma in sensitive individuals.
Triatoma protracta
western bloodsucking conenose
Triatoma protracta is a blood-feeding assassin bug in the subfamily Triatominae, commonly known as the western bloodsucking conenose. Native to western North America, it serves as a vector of Trypanosoma cruzi, the protozoan causing Chagas disease, though its vector efficiency is considered secondary to some congeners due to its relatively long development time and defecation behavior. The species is primarily associated with woodrat (Neotoma) nests and occasionally invades human dwellings, where it may bite and cause allergic reactions. Laboratory studies indicate egg-to-adult development averages 6.7 months with 72.5% egg eclosion rates.