Parasitus

Harmfulness rating

HARMFUL | NOT HARMFUL | UNCERTAIN

neutral to beneficial; habitat generalist predator

Name

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, deutonymphsdeutonymph:
Ontogenetic stage between protonymph and tritonymph (or adult, if tritonymph is absent).  See Life stages page for more details.
: Opisthogastric regionopisthogastric region:
Ventral body behind legs IV. Also known as opisthogaster and ventral opisthosoma.
with fewer than 30 pairs of setae (Fig. 2). Setae al of palppalp:
Second (after chelicera) paired appendage of the gnathosoma. Has a sensory function, but may be variously modified for other functions (e.g., raptorial, attachment to host, or filtering).
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: Tritosternumtritosternum:
In Mesostigmata, a  biflagellate structure situated on the ventral side of the body, posterior to the gnathosoma and anterior to the sternal shield. Sometimes the flagellae (laciniae) are partially or completely fused. 
of male absent or modified.

Species identification

A dichotomous key is available in Hyatt, 1980Hyatt, 1980:
Hyatt, K. H. 1980. Mites of the subfamily Parasitinae (Mesostigmata: Parasitidae) in the British Isles. Bulletin of the British Museum (Natural History) Zoology. 38: 237-378..

Similar genera

In Vulgarogamasus, setae of dorsal hexagon almost similar in form. Base of male tritosternumtritosternum:
In Mesostigmata, a  biflagellate structure situated on the ventral side of the body, posterior to the gnathosoma and anterior to the sternal shield. Sometimes the flagellae (laciniae) are partially or completely fused. 
never closely associated with genital orifice. In Parasitus, setae of dorsal hexagon different in form: setae z5 stout and pilose and j5 and j6 simplesimple:
Of claws or setae; not modified or not bi- or trifurcate at tip.
, and base of male tritosternumtritosternum:
In Mesostigmata, a  biflagellate structure situated on the ventral side of the body, posterior to the gnathosoma and anterior to the sternal shield. Sometimes the flagellae (laciniae) are partially or completely fused. 
closely associated with genital orifice. In Parasitellus, the opisthogastric regionopisthogastric region:
Ventral body behind legs IV. Also known as opisthogaster and ventral opisthosoma.
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

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

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 phoreticphoretic:
  Pertaining to phoresy; using another organism (i.e., a host) for dispersal to new habitats. Phoresy can be distinguished from parasitism because feeding typically does not occur during phoresy.
  stage (deutonymphdeutonymph:
  Ontogenetic stage between protonymph and tritonymph (or adult, if tritonymph is absent).  See Life stages page for more details.
  ) 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., 2013Szafranek et al., 2013:
Szafranek, P., M. Lewandowski amp; M. Kozak. 2013. Prey preference and life tables of the predatory mite Parasitus bituberosus (Acari: Parasitidae) when offered various prey combinations. Experimental and Applied Acarology. 61: 53-67.). Typically, mite deutonymphsdeutonymph:
Ontogenetic stage between protonymph and tritonymph (or adult, if tritonymph is absent).  See Life stages page for more details.
are phoreticphoretic:
Pertaining to phoresy; using another organism (i.e., a host) for dispersal to new habitats. Phoresy can be distinguished from parasitism because feeding typically does not occur during phoresy.
on dung beetles (Hyatt, 1980Hyatt, 1980:
Hyatt, K. H. 1980. Mites of the subfamily Parasitinae (Mesostigmata: Parasitidae) in the British Isles. Bulletin of the British Museum (Natural History) Zoology. 38: 237-378.). 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.