Larval Anatomies, Eggs, and Developmental Biologies of Centris bicornuta and Epicharis albofasciata (Apoidea: Apidae) Author Rozen, Jerome G. text American Museum Novitates 2017 2017-05-02 2017 3879 1 20 http://www.bioone.org/doi/10.1206/3879.1 journal article 10.1206/3879.1 0003-0082 5369087 EGG OF CENTRIS ( HETEROCENTRIS ) BICORNUTA MOCSÁRY Figures 26, 28, 29 DIAGNOSIS: Eggs of C. bicornuta and E. albofasciata are similar in shape, color, gross structure, and overlap in size, but are easily distinguishable by differences in chorionic microstructure. That of C. bicornuta consists of a pebbled surface (fig. 29), and that of E. albofasciata , an elevated latticework (fig. 30). Furthermore, the micropyle of C. bicornuta (figs. 28, 29) is surrounded by a radiating network of low elevated ridges that are absent in E. albofasciata (fig. 30). DEScRIPTION: Most specimens cream color, but several pale bluish (presumably a postmortem change). Chorion smooth, uniform but nonreflective as seen by stereomicroscope, but strongly, uniformly pebbled in SEM examination (fig. 29). Shape (fig. 26) gently curved, elongate, tending to be parallel sided, but some slightly larger at posterior end; rounded at both ends; polarity not evident without SEM examination or embryo orientation. Length 2.9–3.4 mm; maximum diameter 0.6–0.7 mm. Micropyle evident only on SEM examination, found at anterior end associated with an elevated network of ridges leading to dense cluster of micropylar pores (figs. 28, 29). MATERIAL STUDIED: Nineteen eggs: Costa Rica : Guanacaste Prov. : 9 km NW Bagaces , II-17-2009 (Frankie Group) .