S139

Pylospira octopyle Haeckel?

Pylospira octopyle Haeckel, 1887, p. 698, pl. 49, fig. 4

DESCRIPTION: Shell ellipsoidal in outline, composed of a series of spiralling chambers supported by numerous cylindrical radial beams which piece the outer shell margin. Outer shell thorny, bearing subcircular pores, irregular in size, shape and distribution. (Gail Lombari, unpublished data).

DIMENSIONS: Based on 10 specimens; length of major axis 101-122 microns, of minor axis 79-106 microns. (Gail Lombari, unpublished data).

REMARKS:

1. The specimen illustrated by Benson (1966, pl. 17, fig. 2) as Phorticium pylonium is probably conspecific.

2. ''The identification of this species is questionable because the test illustrated by Haeckel is much more regular than the forms observed in this study" (from Molina-Cruz, 1975).

3. Tholospira (?) sp. 2 in Sachs (1973) is thought to be conspecific although the dimensions given by him are rather larger.

Plate 17, figures 6a-c

Sl40

RECENT DISTRIBUTION:

1. Sachs, 1973, Code 34I (Tholospira (?) sp. 2); ".... widely distributed, but always less than 6% of the fauna of the surface study... loads most heavily on the bottom - influenced factor."

2. Molina-Cruz, 1975, Code S27; used in factor analysis of southeast Pacific assemblages; cf. Appendix 10 for percent S27 at each station.

3. Robertson, 1975, included this species in the synonymy of Phorticium pylonium which he found "loads heavily in factors 3 (transitional). At present it is most abundant in a zone east of about 155 degrees E and between 44 degrees and 50 degrees N. There is a significant southern shift of the zone of highest abundances from the present to 18,000 YBP".