Vol. 51 No. 7, 2012
AMud-Ball Construction by Sceliphron Mud-Dauber Wasps (Hymenoptera: Sphecidae): A Comparative Ethological Study
Liliane Chatenoud1, Carlo Polidori2,*, Matteo Federici3, Veronica Licciardi3, and Francesco Andrietti3
1Istituto di Ricerche Farmacologiche “Mario Negri”, Milano 20156, Italy
2Departamento de Biodiversidad y Biología Evolutiva, Museo Nacional de Ciencias Naturales, Madrid 28006, Spain
3Dipartimento di Bioscienze, Università degli Studi di Milano, Milano 20133, Italy
Liliane Chatenoud, Carlo Polidori, Matteo Federici, Veronica Licciardi, and Francesco Andrietti (2012) Mud-dauber wasps of the genus Sceliphron
build aerial nests using mud collected at humid-soil sources and
carried to the nest in the form of spherical mud-balls. We
recorded and analyzed a series of video-sequences of 5 (3 native and 2
alien) species of Sceliphron
in Italy, in order to compare their mud-ball-building behavior.
Four phases were recognized: I) patrolling the ground in search of a
suitable place for mud-ball building; II) removing leafs, twigs, or
small stones from the chosen area; III) forming the mud-balls; and IV)
flying off with the mud-balls. The duration of all these phases
were similar among species, with the only exception being phase IV,
which was shorter in S. curvatum.
In all species, mud was shaped into a ball by the combined action of
the legs and mandibles, but important differences also emerged in some
details of this behavior. In particular, S. curvatum
maintained the longitudinal axis of its body parallel to the ground as
it worked the mud, and its antennae rapidly tapped the ball. On
the contrary, in the other 4 species, the mud was pulled under the
mentum and retained laterally by the 1st pair of legs, while the body
axis was maintained almost vertical, and the antennae were not involved
in mud shaping. Because S. curvatum
belongs to a different subgenus compared to the other 4 species, we
suggest that mud-ball-building behavior may potentially represent a
useful taxonomic and perhaps phylogenetic character.
Key words: Nesting habits, Nest material, Species-specific behaviour, Mud-dauber wasp.