Ceratina (Ceratinula)

Taxonomy

Family: Apidae
Subfamily: Xylocopinae
Tribe: Ceratinini
Genus: Ceratina Latreille, 1802
Subgenus: Ceratinula Moure, 1941
Common name: small carpenter bees

Overview

This subgenus consists of minute, slightly elongate bees that have mostly smooth and black or brown integument, sometimes with slightly bluish metallic reflections. Their body length ranges from 3–6 mm (Michener 2007).

Diagnostic characteristics

(modified from Michener 2007)

  • Maxillary palpi 5- or 6-segmented.
  • Paraocular area above the antenna and the lower portion of the gena are largely impunctate.
  • Scutum largely impunctate, with only few punctures on its margins or between anterior sulci.
  • Body slightly elongated due to the first metasomal segment semi-pediculate.
  • Forewings with second submarginal cell narrowed almost to a point anteriorly.
  • Preoccipital carina may be present or absent.
  • Male paraocular area with pale maculations, which are sometimes also present in females.

May be confused with

Some species of Ceratina (Ceratinula) may be confused with Ceratina (Ceratina), and they have at times been included in the same subgenus (Hirashima 1971a; Michener 1965). Species of C. (Ceratinula) differ from typical species of C. (Ceratina) in their extensive smooth, impunctate areas. They often completely lack punctures on the paraocular area above the antenna and on the genae. C. (Ceratinula) also have forewings with the second submarginal cell narrowed anteriorly, nearly to a point. In addition, their distribution is different; C. (Ceratinula) has a primarily Neotropical distribution, while C. (Ceratina) has an African distribution.

Host associations

Ceratina (Ceratinula) arizonensis have been observed visiting a number of plant families including: Apiaceae, Asteraceae, Boraginaceae, Epialtidae, Euphorbiaceae, Lamiaceae, Onagraceae, Papaveraceae, Polemoniaceae, Polygonaceae, Rhamnaceae, Scrophulariaceae, Tiliaceae (Daly 1973; Collevatti et al. 1998; Ascher & Pickering 2020).

Nesting behavior

Michener and Eickwort (1966) described an undeterrmined species of Ceratinula (similar to Ceratina rectangulifera, Schwarz & Michener) nesting in dead stems collected along a shady bank in Costa Rica. The nest was associated with 1 to 5 cells, burrows of about 2.5 mm in diameter, cells between 4 and 5.5 mm in length with partitions as thick as 0.5 to 0.75 mm, and with pollen masses attached to one side of the cell as in other species of Ceratina. Rehan et al. (2015) observed social nesting (in terms of nest reuse) in three Neotropical species of Ceratinula from Panama (C. buscki, C. tricolor and C. zeteki); however, they concluded that because this social behavior was rare, solitary nesting is likely an adaptive trait.

Diversity

Ceratina (Ceratinula) includes 36 described species, two of which are known to occur in the U.S. (Ascher and Pickering 2020).

Known invasives

Ceratina (Ceratinula) arizonensis has been inadvertently introduced from the North America into Hawaii. It was first reported on Oahu in 1950 and has since established and spread to other Hawaiian islands (Hirashima 1971a).

Distribution

Ceratinula have a subtropical to tropical distribution in the Western Hemisphere, occurring from the most southern states of the U.S., south through the tropics to Argentina (Michener 2007).

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

<p><em>Ceratina</em> sp. female face, photo: Joshua Hengel</p>
Ceratina sp. female face, photo: Joshua Hengel
<p><em>Ceratina</em> sp. female lateral habitus, photo: Joshua Hengel</p>
Ceratina sp. female lateral habitus, photo: Joshua Hengel
<p><em>Ceratina</em> sp. female dorsal habitus, photo: Joshua Hengel</p>
Ceratina sp. female dorsal habitus, photo: Joshua Hengel
<p><em>Ceratina</em> sp. male face, photo: Joshua Hengel</p>
Ceratina sp. male face, photo: Joshua Hengel
<p><em>Ceratina</em> sp. male lateral habitus, photo: Joshua Hengel</p>
Ceratina sp. male lateral habitus, photo: Joshua Hengel
<p><em>Ceratina</em> sp. male abdomen, photo: Joshua Hengel</p>
Ceratina sp. male abdomen, photo: Joshua Hengel