Raymentia

 

HARMFUL | NOT HARMFUL | UNCERTAIN

unknown; probably feeds on pollen

Name and classification

Raymentia Womersley, 1956

Taxonomy
Superorder Parasitiformes » Order Mesostigmata » Suborder Monogynaspida » Hyporder Dermanyssiae » Family Laelapidae » Genus Raymentia

Type species
Raymentia anomala Womersley, 1956

Diagnosis

Female: Fixed digit of chelicerae with large tooth and multidentate crown (Fig. 5). Movable and fixed digit of chelicerae each with large terminal hook (Fig. 5).

Other diagnostic characters

Female: Epigynal shield flanked by auxiliary shields (Fig. 4). Sternal shield with "eroded" posterior margin (Fig. 3). Idiosomal shield narrows posteriorly (Fig. 1).

Similar genera

Our collection includes an undescribed species from the halictid bee Caenaugochlora costaricensis from Costa Rica. It has large chelicerae, with terminal hooks on both digits, and nude epigynal shield (as in all species of Raymentia, except for R. anomala). However, there are no auxiliary shields on the sides of the epigynal shield (present in Raymentia); the sternal shield does not have "eroded" posterior margin ("eroded" in Raymentia); and the idiosomal shield does not conspicuously narrow posteriorly (conspicuously narrows posteriorly in Raymentia). Thus, the scope of Raymentia should be expanded or a new genus proposed for the species from Caenaugochlora costaricensis.

Distribution

Australia

Bee hosts

halictid bees of the genus Lasioglossum, subgenus Parasphecodes

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

permanent

Host associations, feeding, and dispersal

  • All stages presumably live in nests of halictid bees.
  • Females disperse on adult bees.

Biology

The biology of this genus is unknown. All specimens are phoretic females collected on museum specimens of bees. It has been hypothesized that species of this genus are primarily pollenkitt-feeders (Walter et al., 2002), as the tong-like chelicerae would be well suited to collecting nectar-coated pollen grains and holding them during external digestion (Royce and Krantz, 1989). This type of interaction is probably best considered kleptoparasitism, and it would seem to be at least weakly detrimental to the developing bee larvae. However, the actual fitness effects of a mite-bee interaction can be difficult to assess. Given the relatively large size of species of Raymentia, the drain on the pollen resources for developing bees could be significant. However, if species of bee host Lasioglossum overstock their nest cells or if the developing larvae produce residues that are the primary food of the mites, then the relationship could be commensal or even mutualistic.