S71

Styptosphaera (?) spumacea Haeckel

?Styptosphaera spumacea Haeckel, 1887, p. 87; Nigrini, 1970, p. 167, pl. 1, figs. 7, 8.

DESCRIPTION

"Shell spherical, composed entirely of loose, irregular spongy meshwork. Pores are subcircular and of varying size. No central cavity or radial spines. Surface rough, but without thorns." (from Nigrini, 1970).

"The appearance is of a densely interwoven mesh-work ball, without protruding spines or thorns." (from Sachs, 1973).

DIMENSIONS

"(based on 20 specimens). Diameter of shell 119 to 167 microns." (from Nigrini, 1970).

"diameter 166 +/- 16 microns. (based on 15 measurements)" (from Sachs, 1973).

REMARKS

1. "S. spumacea was described, but not illustrated, by Haeckel (1887) from 'Challenger' station 236 (34 degrees 58 minutes N, 139 degrees 29 minutes E), but no specimen of this general form could be found in topotypic material examined by the author. Haeckel's unillustrated description appears to fit the form found in the North Pacific during the study. However, the shell diameter given by Haeckel is almost twice that of the North Pacific specimens which are, therefore, only tentatively assigned to S. spumacea." (from Nigrini, 1970).

Plate 8, figures 6a, b

S72

RECENT DISTRIBUTION

1. Nigrini, 1970, fig. 7; belongs to a subarctic assemblage derived by recurrent group analysis of North Pacific samples.

2. Sachs, 1973 Code 9S, fig. 2B; "General aspect is Southern, [i.e., south of about 45 degrees N], but greatest abundance is slightly North of the Southernmost stations."

3. Robertson, 1975; "This species loads most heavily in factor 3 (transitional). At present this species is most abundant in a band between 37 degrees and 45 degrees N. To the extreme north and south it is absent. The area where it is absent at 18,000 YBP is poorly defined but may show a shift to the south in the western part of the northwest Pacific."