G. it. Ent., 11 (52): 109-112
December 2004
Xylocopa (Xylocopa) violacea (Linneo, 1758)
(Hymenoptera: Apidae):
studio preliminare sul dimorfismo sessuale. II
di
SALVATORE VICIDOMINI
Abstract - Xylocopa (Xylocopa) violacea (Linnaeus, 1758) (Hymenoptera: Apidae): preliminary study on the sexual dimorphism. II - A quantitative study on the head sexual dimorphism (F-M%) in a Campanian (South Italy) pupae population of Xylocopa violacea (L.) (Apidae: Xylocopini). Sexual dimorphism is significant for all characters (F-M% ≥ 1). For two characters, male mean is higher than the female one [F-M% < 0; Fr, Fx(XI)], mainly for the male additional flagellomere. Little significant (1 ≤ F-M% < 5) is the sexual dimorphism for OCmin. LgSC1/2, FI and Fx(XI) characters; highly significant (F-M% > 30) for OVP-MPC, OVP-OC, LgMb and LgM1/2 characters; normally significant (5 ≤ F-M% ≤ 30) for the other 19 characters. Antennae characters show a non significant sexual dimorphism (F-M% = 0.42) for their important function in both sexes. Compound eyes (12.71) and toruli (13.95) characters are only affected by the different sizes of the two sexes, because show the same dimorphism of pupal total length. Visual ocelli (32.61) and mandibles (31.18) characters show a significantly higher sexual dimorphism with respect to pupal total length, mainly because the nest is bored by the female only.
