generalist predators that are expected to be neutral to beneficial, but may be harmful if they can enter brood cells; preys on microarthropods in bee nests

Name and classification

Blattisocius Keegan, 1944

Superorder Parasitiformes » Order Mesostigmata » Suborder Monogynaspida » Hyporder Dermanyssiae » Family Blattisociidae » Genus Blattisocius

Type species
Blattisocius triodons Keegan, 1944 (=Lasioseius tarsalis Berlese, 1918)

Common synonyms
Paragarmania Nesbitt, 1951 (this synonymy has not been accepted by all authors; in these references (Bregetova, 1977c; Karg, 1971), Paragarmania is treated as a separate genus).


Female: Dorsal shield undivided and without midlateral incisions (Figs. 1, 3). Sternal shield with 3 pairs of setae (Fig. 20) or st3 on partially separate platelets (Figs. 4, 5, 6, 7); st4 situated on soft cuticle (Fig. 20) or on corners of sternal shield platelets (Figs. 4, 6, 7). Metsternal shields absent (Figs. 4, 6, 7, 20). Ventrianal shield elongated, subtriangular to bullet-shaped, bearing 3-4 pairs of ventral (preanal) setae (JV, ZV), in addition to the three circumanal setae (Figs. 8, 9). Adanal setae inserted anterior to hind margin of anus (Figs. 8, 9). Peritrematic shield slender, barely wider than stigma at level of stigma (Fig. 10). Corniculi narrowly separated, slender (Fig. 11). Fixed digit with filiform pilus dentilis (Figs. 12, 17). Tectum convex (Fig 16).


Worldwide. Species associated with bees have been found in the Nearctic (Canada), Palaearctic (Czech Republic, Poland, Russia, and Ukraine), Neotropical (Argentina), Oriental (India), and Australasian (New Zealand and Australia) regions.

Bee hosts

Members of this genus have been found in honey bee (Apis) hives (e.g., B. tarsalis) and on adult honey bees (e.g., B. apisassociae and B. apis). Blattisocius tarsalis has also been found in nests of leafcutter bees Megachile gomphrenae and M. pallefacta.

Host association level


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


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


Host associations, feeding, and dispersal

  • All stages are probably predatory on microarthropods in habitats where they are found, including honey bee hives. Some species may feed on eggs of larger insects or attack their larvae.
  • Females of a few species (B. apisassociae and B. apis) have been found on honey bee workers, indicating a possibility of phoresy. Mites probably also invade nearby bee nests by walking.


Six species (Blattisocius apis, B. apisassociae, B. dentriticus, B. keegani, B. mali, and B. tarsalis) have been recorded from hives of honey bees or on adult bees.

Species of Blattisocius are also predators in soil, stored food, the nests of small mammals and birds, ripe, dried, and rotting vegetables, on plants (e. g., roses, apple trees, and Citrus trees), and in insect cultures. Prey may include acarid mites. One species, Blattisocius patagiorum (Figs. 18-20), is parasitic on adult noctuid moths.