Sennertionyx

 

HARMFUL | NOT HARMFUL | UNCERTAIN

lives in bee nests, but details of biology in nests unknown

Name and classification

Sennertionyx Zachvatkin, 1941

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

Type species
Trichotarsus manicati Giard 1900

Common names
wool carder bee mite

Diagnosis

Phoretic deutonymph: Anterior extensions of coxal apodemes III long, almost reaching lateral sides of body (Fig. 2). Coxal setae 1a filiform, not conoidal (these setae break off easily in slide-mounted specimens, and appear as alveolar) (Fig. 2). Coxal setae 3a, 4a alveolar (not conoidal) (Fig. 1). Empodial claws I-III large, twisted, and hook-like (Fig. 2). Empodial claw IV distinctly smaller than claws I-III (Fig. 2). Three long setae on tarsus IV (Fig. 2). Tarsal setae aa I absent, setae ba I-II present.

Species identification

This genus includes only one described species, Sennertionyx manicati. However, undescribed species are known (our data).

Similar genera

By the presence of enlarged, twisted claws and coxal sclerotization, this genus is similar to Cerophagopsis. Sennertionyx differs from Cerophagopsis by its smaller claw IV as compared to claws I-III (claws I-IV are subequal in Cerophagopsis), the presence of tarsal setae aa I (absent in Cerophagopsis), and the presence of 3 long setae on tarsus IV (1 in Cerophagopsis).

Distribution

Sennertionyx manicati: France, Spain, Italy, Greece, Netherlands, and former USSR, including SE Russia. Undescribed species known from North America.

Bee hosts

Anthidium manicatum and other species of Anthidium. Also found on Stelis punctulatissima, a kleptoparasite of the principal host (Heitmans, 2013).

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 live in nests of megachilid wool carder bees Anthidium spp. Food preferences and biology in the nest are unknown.
  • Phoretic deutonymphs disperse on bee hosts (both males and females) and their bee kleptoparasites (i.e., Stelis punctulatissima).

Biology

In the Netherlands, phoretic deutonymphs have been found in late May to late August on both male and female bees. The mites usually attach themselves to the propodeum and metasomal tergite I. At high densities, the mites may also attach to each other by clinging to each other using their powerful forelegs and claws. These mites can also be found in the intersegmental spaces below the posterior metasomal tergite (Heitmans, 2013). Biology in the nest is unknown.