Dinogamasus, Kramer, 1898

Abo-ShnafK, Reham, KamelK, Marwa S., SheblK, Mohamed A., BadawyK, Rawda M. & OkelyK, Mohammed, 2024, New species of genus Dinogamasus Kramer (Mesostigmata, Laelapidae) associated with large carpenter bees (Hymenoptera: Apidae) in Egypt, with new concepts of the genus, Acarologia 64 (1), pp. 43-55 : 53

Relationship of Dinogamasus to its related genera Raymentia Womersley and Stigmatolaelaps Krant

Only Dinogamasus species have a nude genital shield among bee-associated laelapids; however, Raymentia shares none of the other striking synapomorphies of Dinogamasus species, such as

the absence of deutosternal denticles, loss of peritreme, sternal shield with 1–2 pairs of setae, blunt corniculi, retention of the protonymphal chaetome on the palp-tibia of the adult, and extensive idiosomal hypertrichy ( Lundqvist 1999).

A nude genital shield, eroded sternal shield, and the enlarged peritrematal atrium of Raymentia argue for a relationship to the Dinogamasus-Stigmatolaelaps clade ( Krantz 1998 ; Lundqvist 1999). The stigma is typically about the same width as the peritreme, but distinctly enlarged in Raymentia , Stigmatolaelaps and Dinogamasus ( Moraes et al. 2022) .

Raymentia species, according to Walter et al. (2002), are primarily pollenkitt-feeders, as the tong-like chelicerae would be well suited to capturing nectar-coated pollen grains and keeping them during external digestion ( Royce and Krantz 1989). This form of interaction is probably best considered kleptoparasitism or food theft, and appears to be at least marginally harmful to the developing bee larvae.

However, as the complex relationship between Dinogamasus and Xylocopa spp. demonstrates, the actual fitness implications of a mite-bee interaction can be challenging. Given the relatively large size of Raymentia species, the pollen resource drain on developing bees could be severe. The two large genera of laelapid bee mites, Dinogamasus and Stigmatolaelaps , are

nest associates of carpenter (Xylocopinae) and leaf-cutting ( Megachilidae ) bees in Asia and Africa ( Krantz 1998 ; Lundqvist 1999).