Thyreophagus

 

HARMFUL | NOT HARMFUL | UNCERTAIN

neutral to beneficial; presumably feeds on decomposing organic matter and/or associated fungi in bee nests

Name and classification

Thyreophagus Rondani, 1874

Taxonomy
Superorder Acariformes » Order Sarcoptiformes » Suborder Oribatida » Infraorder Desmonomata » Hyporder Astigmata » Family Acaridae » Genus Thyreophagus

Type species
"Thyreophagus entomophagus Laboulb." (=Acarus entomophagus Laboulbène, 1852 (nom. nud.), Tyroglyphus entomophagus Laboulbène and Robin, 1862, Thyreophagus entomophagus (Laboulbène and Robin, 1862))

Common synonyms
Fumouzea Zachvatkin, 1953, Michaelopus Fain and Johnston, 1974, Monieziella Berlese, 1897 (=Moniziella Berlese, 1897 variant spelling).

Common names
Thyreophagus flour mite

Diagnosis

Phoretic deutonymph: Eyes present, widely separated, represented by pigmented eyespots (retinae) and distinct lenses (Fig. 3).

Other diagnostic characters

Phoretic deutonymph: Tarsal setae aa I absent. Setae ba I absent, ba II present (not correlated with adults). Setae ve absent (can be topologically misinterpreted as se). Coxal apodemes III-IV ending freely, not closed (Fig. 4). “Saucer” at the end of tarsal setae e I-II present. Genu I with one solenidion (σ). External conoidal setae (ps2) of attachment organ slightly posterior to median suckers (ad1+2) (Fig. 4). Solenidion σ III and setae nG III absent. Coxal setae 1a, 3a minute, filiform, 4a conoidal.

Adult: Body elongated (Figs. 5, 6). External vertical setae (ve) represented by alveoli, located on lateral sides of prodorsal shield, approximately midway between vi and scapular setae se (Fig. 7). Setae ba I-II absent, famulus (in Astigmata, a small, hollow, and optically active seta- or spine-like structure located just distally to solenidion ω1 on tarsus I) present, enlarged, spiniform (alternatively famulus can be interpreted as ba I) (Fig. 11). Hysterosomal setae c1, c2, and d1 absent; setae f2 absent (Fig. 8). Male with sclerotized projection extending from posterior opisthosoma (Fig. 9). Projection is broad, with seta h1. In male, bases of setae h2, h3 and ps1 arranged in a triangle on ventral surface of posterior sclerotized projection (Fig. 10).

Distribution

Worldwide; has been found in association with bees in the Palaearctic (Apis mellifera) and Neotropics (stingless bees).

Bee hosts

European honey bee (Apis mellifera) hives and stingless bee (Meliponini) nests

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 several habitats, including beehives and nests of stingless bees, where they presumably feed on decomposing organic matter and/or associated fungi.
  • Phoretic deutonymphs are not known from bees but are known from other insects. Dispersal of feeding stages is known on rodents, but this may be an accidental record.

Biology

Among bee hosts, three generalist species of Thyreophagus have been found in debris from beehives of Apis: Thyreophagus corticalis, Thyreophagus entomophagus, and Thyreophagus odyneri. Under laboratory conditions, these species prefer bee bread, pollen, bee hive debris, and mold; Th. entomophagus has also been observed feeding and reproducing on dead brood bees, and the two other species on wax and combs; no reproduction has occurred on honey, royal jelly, or propolis for either species (Chmielewski, 1991c).

Feeding stages of Th. entomophagus have also been found on a museum specimen of the bumble bee Bombus lapidarius. A species of Thyreophagus was found in moldy nest material of stingless bees in the Neotropics (our data, Fig. 13).

Species of this genus inhabit different habitats and as phoretic deutonymphs use a large array of animals for dispersal: collembolans, beetles, ichneumonids, ants, fleas, birds, and mammals. Adults and other feeding stages are found in decomposing plant material, forest litter, soil, stored food including flour, sporocarps of bracket fungi, flowers, house dust, nests of birds, or on rodents themselves. Some species are associated with scale insects (Diaspididae) and were suggested to be "parasitic." Thyreophagus entomophagus attacks entomological collections and can be found on insect museum specimens. It is not always clear whether the occurence of this mite results from deutonymphs that molt on the same hosts and subsequently establish a colony or because of mites that spread from different insect specimens stored in museums.