54 ENTOMOLOGICALNEWS SCIENTIFIC NOTE THE BEE GENUS MYDROSOMA IN COSTA RICA (HYMENOPTERA: COLLETIDAE)1 CharlesD.Michener The dissoglottine genus Mydrosoma, consisting ofrarely collected, moderate sized to large (10 to 17 mm body length) bees, is known from Mexico to Argentina, but in Central America it has been reported only from Panama (M. brooksi Michener, 1986). It is therefore ofinterestto report a male specimen ofM. brooksi in the collection ofInBio (Institute Nacional de Biodiversidad) in Heredia, Costa Rica, borrowed for study by R. W. Brooks. The data are as follows: Guanacaste Province: Estacion Pitilla,9 km south of Santa Cecilia, 700 m elevation, March 1990 (P. Rios, C. Moraga & R. Blanco), no. 177060. The specimen differs from Panamanian specimens of M. brooksi in that the midbasal projection of sternum 5 is an acute tubercle, not a short transverse lamella suggesting atubercle. My firstreaction was to think it represented a new species, but since its other characters including those of the hidden sterna and genitalia are as in M. brooksi, I think it is that species. The structure of sternum 5 ofthe Costa Rican specimen requires a change in couplet 7 ofthe key to species (Michener, 1986, p. 199); the second alternative should read "S V with short, transverse, median basal lamella oracute tubercle; first flagellomere ..." (italics added). LITERATURE CITED Michener, C.D. 1986. A review of the tribes Diphaglossini and Dissoglottini (Hymenoptera, Colletidae).UniversityofKansas ScienceBulletin 53:183-214. 1ReceivedandacceptedAugust 19,2002. :Entomology Division,Natural History Museumand Entomology Program,DepartmentofEcology and Evolutionary Biology, University of Kansas, Lawrence, Kansas 66045, U.S.A. E-mail: [email protected]. MailedonApril 9,2004