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Verticillata hexacantha Popofsky, 1913

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Benson, 1966, p. 397-399; pl. 26, fig. 3:

Verticillata hexacantha Popofsky

Verticillata hexacantha Popofsky, 1913, Deutsche Sdpolar-Exped., vol. 14, pp. 282-283, text-fig. 11.

Test consisting of a single, large, lobate, campanulate joint corresponding to the cephalis; the surface of this joint with scattered short spines merges with the three, equally disposed, equal basal feet which extend from the dorsal and primary lateral bars, although in a few specimens an indistinct constriction separates the feet from the test; the upper surface of the cephalis merges with the long, proximally latticed, centrally located, vertical to curved, three-bladed apical horn. A three-bladed vertical horn with slight downward curvature extends from the long, thin, cylindrical, internal vertical bar. Lattice of the test very irregular, consisting of relatively small, unequal pores; outline of test irregular, with irregular lobes separated by thin ribs in the wall of the test; the ribs correspond to the apical-lateral arches and a rib lying in the sagittal plane and joining the apical horn with the dorsal foot. Median bar lies in the approximate plane of the basal mouth of the test; the dorsal and primary lateral bars extend as ribs in the flat, latticed, inner sides of the hollow, proximally latticed, convex outward feet which have solid, three-bladed terminations. The apical bar is a centrally located, thin, cylindrical colurnella with two to three verticils of three branches, each branch joining with one of the thin ribs in the wall of the cephalis. Two to three verticils of paired, outward divergent spines lying in the approximate curved plane of the basal mouth and joining with its margin (collar ring) are present on the long, thin, cylindrical, dorsal and primary lateral bars.

Measurements; based on 6 specimens from stations 27, 34, 60, and 115: maximum length of test including apical horn and feet 221-277 m; maximum breadth of cephalis 92-111 m, between outer margins of feet 123-135 m; length of cephalis (from median bar to base of solid portion of apical horn) 68-98 m, of apical horn 50-90 m, of vertical horn 30-40 m, of feet 74-123 m.

Remarks. This species is identical with Popofskys illustration and description of Verticillata hexacantha Popofsky (1913, pp. 282-283, text fig. 11) except for the lack of the ventral sagittal spine. This spine was not observed in any of the Gulf specimens, and its presence in the single specimen described by Popofsky may have been misinterpreted by him. His illustration does not show it originating from the median bar; it appears to represent an accessory spine originating from the right primary lateral foot.

Distribution. In the Gulf this species is very rare but occurs as far north as station 184. It is absent at stations 27, 90, 95, 130, 133, 136, and all those north of station 184. Its more general occurrence and slightly higher frequency in the southern Gulf indicates its greater affinity for oceanic than for Gulf waters.
Popofsky (1913, p. 283) reported this species from the southern tropical Atlantic, near the west coast of South Africa. Its apparent absence from high latitudes indicates that it is a tropical and possibly temperate species, present in at least the Atlantic and Pacific Oceans.
Benson 1966











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