Key To Genera

la. Apical pore fields present 2

lb. Apical pore fields missing (one or two small apical pores present). . . 3

2a. One labiate process at each valve apex Rhaphoneis, p. 251

2b. One labiate process at each valve apex and usually also near center of lateral margins Adoneis, p. 248

3a. Valve striae aligned across sternum Delphineis, p. 248

3b. Valve striae alternate, not aligned across sternum Neodelphineis, p. 249

Genus Adoneis G. W. Andrews 8c P. Rivera 1987 Type: Adoneis pacifica G. W. Andrews 8c P. Rivera. Monospecific genus.

Adoneis pacifica G. W. Andrews 8c P. Rivera (Plate 51) Reference: Andrews 8c Rivera, 1987. Valve view: Broadly lanceolate with smoothly rounded lateral margins and slightly produced rounded apices. Sternum narrow and distinct. Striae radiate. Single row of areolae on valve mantle continuous around apices. An apical pore field at each pole. One labiate process at each pole and usually one near the center of one or both lateral margins. Morphometric data: Apical axis, 29-95 jurn; transapical axis, 20-47 ju,m; six to eight valve areolae in 10 fim.

Distribution: Chilean coastal waters, California coastal waters (Lange, personal communication).

Genus Delphineis G. W. Andrews 1977, 1981 (Plate 51, Table 63) Type: Delphineis angustata (Pantocsek) Andrews. Basionym: Rhaphoneis angustata Pantocsek. References: Ehrenberg, 1841a, p. 160, Plate 4, Fig. 12; Van Heurck, 1880-1885, Plate 36, Figs. 26 and 27; Boden, 1950, p. 406, Fig. 87; Hustedt, 1959, p. 173, Fig. 679; Drebes, 1974, p. 103, Figs. 84a and 84b; Simonsen, 1974, p. 35, Plate 23, Figs. 2-8; Andrews, 1977,1981; Fryxell 8c Miller, 1978, p. 116, Figs. 1-10; Round et al., 1990, p. 410.

The genus comprises several fossil species (Andrews, 1977).

Characters common to recent species:

Cells solitary or in shorter or longer ribbons.

Valve outline linear or broadly elliptical to lanceolate.

Striae parallel to slightly radiate.

Rows of two or three areolae continue around valve apices.

TABLE 63 Morphometric Data of Delphineis spp.

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