Epeoloides coecutiens (Fabricius, 1775)

ROZEN JR., J. E. R. O. M. E G., 2001, Ovarioles and Oocytes of Two Old World Cleptoparasitic Bees with Biological Notes on Ammobatoides (Hymenoptera: Apidae), American Museum Novitates 3326, pp. 1-12 : 5-6

Epeoloides coecutiens

BIOLOGY: Observations have not yet been made on how and when the egg of any Osirini , including Epeoloides , is introduced in the host cell. Furthermore, the method of elimination of the host immature (be it egg or larva) is also unknown. To date, most known cleptoparasitic Apidae have early (usually first) instars with modified head capsules and long, sharply pointed mandibles that kill the host egg or usually young larva. Such Apidae include the Nomadinae , Melectini , Isepeolini , Rhathymini , Ericrocidini , Protepeolini , and Tetrapedini (see Rozen, 1991, and references therein; information on Tetrapedini [i.e., Coelioxoides ] is new and will be reported fully elsewhere). The only recorded exception is Exaerete ; Bennett ( 1972) provided a detailed description of a female E. dentata (Linnaeus) opening the closed cell of Eufriesea surinamensis (Linnaeus) , removing the host egg, and crushing it with her mandibles.

DESCRIPTION OF MATURE OOCYTES ( figs. 3, 10–14): Size moderately large relative to distance between outer rim of tegulae (i.e., egg index 0.70); length 2.02–2.11 mm; maximum diameter 0.37–0.38 mm; total number of mature oocytes per ovariole 4–5. Shape ( figs. 3, 10) approximately symmetrical along its moderately curved long axis, elongate, rounded at anterior end, gradually, evenly tapering posteriorly, narrowly rounded posteriorly; maximum diameter immediately behind anterior end; micropylar pore(s) not identified and hence apparently lacking, corresponding to situation in Apis and Bombus (Bronskill and Salkeld, 1978) . Color nearly white.

Chorion dull throughout, appearing granular under low­power magnification, but actually with small, evenly spaced, projecting, rounded nodules under high power or under SEM examination ( figs. 10–14); extreme anterior end ( fig. 12, 13) without nodules but with pattern of elongate ovoids defined by raised borders; these ovoids becoming more elongate toward anterior pole of oocyte so that raised borders obliterate centers of ovoides, there remaining only incised channels separating raised borders; chorion in cross section under high magnification ( fig. 14) consisting of outer spongy, columnar matrix that is somewhat thicker than consolidated, nonfenestrated inner layer; inner layer possibly comprised of two layers.

REMARKS: Alexander ( 1996) provided information on the egg indices of Osirinus lemniscatus Roig­Alsina and Parepeolus aterrimus (Friese) , both of which were somewhat greater than that of Epeoloides coecutiens . Hence, all three representatives of the Osirini have eggs that tend to be large relative to body size compared with many other cleptoparasites.

MATERIAL STUDIED: Five females, Germany: North Bavaria, Bayreuth, Ecological­Botanical Garden of the University of Bayreuth , 49°55.7′N, 11°34.9′E, VII­1–1999 (P. Hartmann) .