Othinosmia

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Osmiini
Genus: Othinosmia Michener, 1943
Subgenera: Afrosmia, Megaloheriades, Othinosmia
Common name: none

Overview

Othinosmia are black bees with white hairs. They generally range in length from 5–8 mm, although one species, O. stupenda, is considerably larger and measures 9–12 mm in body length (Griswold 1994b; Michener 2007).

Diversity

Othinosmia contains 13 described species in 3 subgenera worldwide. It is likely that multiple undescribed species occur (Michener 2007); none are known to occur in the U.S. or Canada.

Diagnostic characteristics

(modified from Michener 2007 unless otherwise stated)

May be confused with

Some Protosmia are similar to some Othinosmia. The T1 lateral line of Othinosmia is longer than in Protosmia, being level with the spiracle (Michener 2007). Distinguishing these genera can be easier by becoming familiar with some of the subgeneric characters of Othinosmia in Michener (2007).

Known invasives

There are no known invasives.

Host associations

Little is known about the floral resources utilized by most species of Othinosmia. Othinosmia schultzei is broadly specialized on Asteraceae (Kuhlmann and Timmerman 2009).

Nesting behavior

The known nesting habits of Othinosmia involve sand, pebbles, and resin to construct nests. Members of the subgenus Megaloheriades are known to nest above ground, attaching their nests to twigs and rocks (Michener 1968). Othinosmia (Megaloheriades) globicola builds aerial nests on twigs out of a matrix of pebbles and yellowish-green resin (Michener 1968). The single cell nests are generally spherical with the nest closure being flattened. Othinosmia (Megaloheriades) schultzei builds similar nests of quartz grains, although they are attached to sandstone rocks and are hemispherical (Kuhlmann and Timmerman 2009). They may reuse old nests or use them as a start to a new nest by adding on to them. The known nests of the Othinosmia subgenus are belowground, with O. (Othinosmia) filifera nesting in stony, dry soils by excavating irregular nests forming one cell lined with resinous material (Michener 1968).

Distribution

Othinosmia only occurs in extreme southwest, sub-Saharan Africa with the exception of O. stupenda, the only species in the subgenus Afrosmia, which occurs in Kenya (Michener 2007). The subgenera Megaloheriades and Othinosmia are known only from Cape Province, South Africa and Namibia (Michener 2007).

​Distribution map generated by Discover Life -- click on map for details, credits, and terms of use.

<p><em>Othinosmia globicola</em> male face, photo: C. Ritner</p>
Othinosmia globicola male face, photo: C. Ritner
<p><em>Othinosmia globicola</em> male lateral habitus, photo: C. Ritner</p>
Othinosmia globicola male lateral habitus, photo: C. Ritner
<p><em>Othinosmia globicola</em> male abdomen, photo: C. Ritner</p>
Othinosmia globicola male abdomen, photo: C. Ritner
<p><em>Othinosmia calviniae</em> male S1 with a with a brush of hair under apical margin, photo: C. Ritner</p>
Othinosmia calviniae male S1 with a with a brush of hair under apical margin, photo: C. Ritner