Parasitus

 

HARMFUL | NOT HARMFUL | UNCERTAIN

neutral to beneficial; habitat generalist predator

Name and classification

Parasitus Latreille, 1795

Taxonomy
Superorder Parasitiformes » Order Mesostigmata » Suborder Monogynaspida » Hyporder Parasitiae » Family Parasitidae » Genus Parasitus

Type species
Acarus coleoptratorum Linnaeus, 1758

Common synonyms
Coleogamasus Tichomirov, 1969; Phorytocarpais Athias-Henriot, 1979 (some authors consider this genus as valid)

Diagnosis

Female, male, deutonymphs: Opisthogastric region with fewer than 30 pairs of setae (Fig. 2). Setae al of palp femur bifid (Fig. 6) or serrate (not spatulate distally or filiform). Setae z5 of dorsal hexagon are markedly different in form from j5 and j6, usually stout and serrate (Fig. 3).

Male: Tritosternum of male absent or modified.

Species identification

A dichotomous key is available in Hyatt, 1980.

Similar genera

In Vulgarogamasus, setae of dorsal hexagon almost similar in form. Base of male tritosternum never closely associated with genital orifice. In Parasitus, setae of dorsal hexagon different in form: setae z5 stout and pilose and j5 and j6 simple, and base of male tritosternum closely associated with genital orifice. In Parasitellus, the opisthogastric region has more than 40 setae (fewer than 30 pairs of setae in Parasitus and Vulgarogamasus).

Distribution

Species associated with bees have been found in the Holarctic region (North America and Eurasia).

Bee hosts

Generalist species have been found in nests of bumble bees (Bombus) and honey bees (Apis).

Host association level

Permanent

associated exclusively with bees or their close relative, wasps; cannot live without these hosts

Temporary

some life stages are associated with bees, while others are not

Facultative or opportunistic

can complete entire life cycle without bees or their close relative, wasps

facultative

Host associations, feeding, and dispersal

  • All stages live together in various habitats, including manure, dung, decaying organic substances, and nests of bumble bees and honey bees, where they feed on nematodes, fly larvae, and other mites.
  • The phoretic stage (deutonymph) uses non-bee carriers to enter bee nests. All stages can probably enter bee nests by walking if a nest is nearby.
  • Dispersal on bees has not been recorded.

Biology

Species of this genus are habitat generalists, living in manure, dung, compost, or other decaying organic substances. They feed on various animal prey, including rhabditid nematodes, mites, and sciarid and phorid fly larvae (Szafranek et al., 2013). Typically, mite deutonymphs are phoretic on dung beetles (Hyatt, 1980). Five named generalist species of Parasitus (Parasitus beta, P. coleoptratorum, P. consanguineus, P. fimetorum, and P. loricatus) have been found in bumble bee nests and beehives. This genus is unlikely to be a harmful parasite though, because it lacks adaptations to prey on bee larvae inside capped brood cells.