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Spongocore puella
Haeckel, 1887
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Description - Add description
Spongocore puella:
Spongy shell cylindrical, without the veil five times as long as broad, three-jointed, with two annular strictures; the middle joint twice as long as either terminal joint. Only the middle joint enveloped by a thin veil with delicate lattice-work and smooth surface; both terminal joints armed with numerous thin, bristle-shaped, radial spines. Breadth of the spongy cylinder twice as large as the distance from the veil. Dimensions – length of the shell 0.25-0.3, breadth (with veil) 0.1 to 0.12; distance of the veil 0.028 to 0.032. | Haeckel 1887 | Benson, 1966, p. 187-189; pl. 8, figs. 1-3:
Spongocore puella Haeckel
Spongocore puella Haeckel, 1887, Challenger Rept., Zool., vol. 18, p.347, Pl. 48, fig. 6.
Spongocore polyacantha Popofsky, 1912, Deutsche Südpolar-Exped., vol. 13, pp. 116-117, text fig. 27.
Fully developed forms consisting of a cylindrical, solid, spongy-appearing test with three joints separated by two constrictions, the middle joint ranging from 1-2 times the lengths of the terminal joints; with numerous, thin, conical, radial spines arising from the surface of all three joints; with the middle joint covered by a spindle-shaped, relatively smooth, thin walled lattice-mantle having small, unequal, irregular pores; mantle supported by numerous radial spines that arise from the middle joint. Mantle absent or rudimentary in most tests, but a complete gradation exists between the incomplete and complete forms. A few tests with radial spines absent or rudimentary. Solid, spongy-appearing part of test not spongy but consists of closely spaced concentric shells. In one specimen the test is bent into a gentle curve.
Measurements; based on 30 specimens from stations 27,and 34: length of test 188-363 µm; diameter of middle joint 37-71 µm, of terminal joints 30-68 µm; length of lattice-mantle 123-191 µm, maximum breadth 74-111 mm; length of radial spines 2-25 µm.
Remarks. No specimens with unbranched spines corresponding in length to those of Spongurus cylindricus Haeckel (1862, p. 465, Pl. 27, fig. 1) were observed from the Gulf, but study of Haeckel’s type material of this species may reveal a gradation to forms with a lattice-mantle. Spongocore polyacantha Popofsky represents an incompletely developed specimen of S. pue1la; several specimens from the Gulf were observed with relatively long radial spines, with those arising from the middle joint having branches or rudimentary structures of the lattice-mantle present at a common level.
Distribution. This species occurs throughout the Gulf as far north as stations 191 and 192. It is rare at all stations except 64 where it is common (2.0%); it is absent at stations 130, 194, 203, 206, 208, and 214. Its higher frequency at station 64 may be explained either by upwelling or by reduction of its dilution by other species. If upwelling does control its distribution, it does so only in this region off the Mexican mainland because at other stations located within areas of upwelling it undergoes no significant increases in its frequency. Its greater frequency in the southern half of the Gulf and its gradual decrease to the north suggests that it has a greater affinity for normal oceanic water masses but is also, to some extent, tolerant of slightly greater salinity and temperature.
Haeckel (1887, p 347) reported this species from the surface of the South Pacific at "Challenger" stations 295-304, off the west coast of Chile within the water mass of the Humboldt Current. Popofsky (1912, p 116) reported Spongocore polyacantha from the western tropical part of the Indian Ocean. The Gulf specimens of this species may have been derived from the water masses of the cold Humboldt Current which would suggest its occurrence in high latitudes. Its occurrence in the tropical part of the Indian Ocean, as well as its presence in the tropical Pacific fauna of the Gulf of California, however, suggests that it is cosmopolitan. | Benson 1966 |
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