Oreopasites (Oreopasites) favreauae Rozen

ROZEN, JEROME G. & ÖZBEK, HIKMET, 2003, Oocytes, Eggs, and Ovarioles of Some Long-Tongued Bees (Hymenoptera: Apoidea), American Museum Novitates 3393, pp. 1-36 : 14-17

Oreopasites (Oreopasites) favreauae Rozen

The following description is based on the same material used by Alexander and Rozen (1987) in their study of the egg index and numbers of ovarioles and mature oocytes of this species (then cited as Oreopasites sp. A ).

MATURE OOCYTE (figs. 25–27): Length 0.65 mm; maximum diameter 0.20 mm (N = 1); egg index 0.49 as indicated by Alexander and Rozen (1987) (dwarf). Operculum with narrow flange only along front and sides (fig. 25); opercular surface about as wide as long, with numerous uneven rounded tubercles that do not invade area behind operculum (fig. 25); dorsal surface behind operculum convex in lateral view, with numerous transverse folds dorsally (as in fig. 28); micropyle a small cluster of pores on slightly raised area near anterior margin of operculum (fig. 26). Chorion of operculum with scattered tubercles and uneven surface (figs. 25, 26); chorion elsewhere smooth, thin, colorless, except ventral chorion nodular with nodules variably expressed and larger (fig. 27) than those of Oreopasites vanduzeei (fig. 29).

MATERIAL STUDIED: Two females, Arizona: Cochise Co., 4 mi E Willcox, IX­5–1986 (J.G. and B.L. Rozen) .

Oreopasites (Oreopasites) vanduzeei Cockerell

The mature oocyte of this species was previously described and illustrated by Rozen (1986a), but the egg index was not calculated and additional details concerning the operculum can now be provided.

MATURE OOCYTE (figs. 28–31): Length 0.68 mm; maximum diameter 0.18–0.20 mm (N = 4); egg index 0.35 (dwarf). Opercular surface slightly concave (fig. 30) (not convex as suggest by Rozen, 1986a: fig. 1), surrounded by complete, thick, circular rim, without flange; oocyte immediately behind operculum (fig. 28) slightly curving dorsally and then immediately curving downward so that dorsal surface outcurved, with fine annulations expressed both dorsally and ventrally, as seen in lateral view; rear somewhat narrowly rounded; micropyle small, multipored area just inside of rim at anterior edge of operculum (fig. 31). Chorion under stereoscopic examination clear, faintly amber, on operculum, glassy; under SEM examination, opercular chorion with raised polygonal boundaries giving surface within rim uniform, shallowly pitted pattern (fig. 30); rim with faint polygonal pattern (fig. 30); chorion elsewhere with faint lines here and there, otherwise smooth except posterior ventral surface nodular, with nodules finer and more evenly spaced (fig. 29) than those of O. favreauae (fig. 27).

MATERIAL STUDIED: Two females, Arizona: Cochise Co., 2 mi E Apache, IV­30–1993 (J.G. Rozen) .

REMARKS: The ovaries of one of the females contained the chorions of numerous reabsorbed oocytes, as noticed for a female of Parammobatodes rozeni , below. These chorions had accumulated in the lower ends of the ovarioles, often clinging to the sides of viable mature oocytes. The most durable part of the depleted oocytes was the pitted operculum. Whereas there were 15 mature oocytes, reabsorbed mature oocytes num­ bered 28. In neither the specimen of Parammobatodes rozeni nor of Oreopasites vanduzeei did we encounter an oocyte that was only partly reabsorbed, suggesting, perhaps, that reabsorption is a quick process.

Oreopasites (Perditopasites) barbarae Rozen

MATURE OOCYTE (figs. 32–34): Length

0.40–0.46 mm; maximum width 0.14–0.16

mm (dorsal width about 0.01 mm greater than lateral width) (N = 9); egg index 0.63 (small). Opercular surface curved, seemingly a continuum with dorsal surface behind it (for alternative interpretation of morphology, see Remarks below), so that dorsal surface of anterior part of oocyte slightly flattened, broader dorsally than laterally; flange so short as to be clearly visible only with SEM, extending along anterior margin of oocyte and clinging to ventral surface and lateral surfaces, as seen in lateral view; flange posteriorly ending in flap (fig. 32); remainder of oocyte shaped about like that of Oreopasites linsleyi (fig. 35); micropyle multipored, at anterior edge of operculum (fig. 34). Chorion clear, colorless; under SEM examination dorsal chorion with polygonal pattern with raised borders from front edge running posteriorly to about twice dorsal width of oocyte (fig. 33); ventral surface smooth, without nodules as found in O. favreauae and O. vanduzeei .

MATERIAL STUDIED: Two females, Arizona: Cochise Co., 13 mi SW Apache, VIII­31– 1988 (J.G. Rozen) .

REMARKS: Several interpretations of the morphology of the mature oocyte of this species (and of that of Oreopasites (Perditopasites) linsleyi ) come to mind. The first, expressed in the description above, is that the posterior boundary of the operculum is lost so that the opercular surface simply grades into the surface behind it, as suggested by the loss of the posterior part of the flange in Oreopasites favreauae (fig. 25) and O. van­ duzeei (fig. 30), even though the opercula of these two taxa are identifiable as being nearly circular. Another interpretation of the anatomy of the mature oocytes of the two species of the subgenus Perditopasites , we think equally supported, is that the operculum has become greatly elongate, so that it is twice as long as wide and its entire surface is expressed by the polygon pattern. The latter explanation is supported, at least in the case of O. barbarae , by the long lateral extension of the flange, which seems to reach for the posterior boundary of the polygonal surface, as seen in figure 32.