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Saccospyris antarctica
Haecker, 1908
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Description - Add description
Saccospyris antarctica
Schale sackförmig-cylindrisch, durch eine schräg verlaufende Querfurche in Cephalis und Thorax abgeteilt, sehr derbwandig, mit rauher Oberfläche, in der Gegend der Ouerfurche und am apicalen Pole mit kurzen, kräftigen Stacheln besetzt, mit wenigen, rundlichen, unregelmäßig großen, sehr zerstreut stehenden Poren. Die Cephalis ist durch eine longitudinale Furche und einen aufsteigenden, stark verzweigten Ast des Innenskelettes in zwei ungleich große Logen geteilt (Fig. 590). Von der einen Kammer wird außerdem durch eine Ouerfurche und durch zahlreiche Aeste des Innenskelettes ein zwischen Cephalis und Thorax einseitig gelagerter Zwischenlobus abgeteilt (Fig. 590, links), so daß die Schale an diejenige mancher Botryoideen (vergl. Rep., Taf. XCVI) erinnert. Der durch die schräg verlaufende Querfurche abgeteilte Thorax ist entweder so hoch wie die Cephalis (Fig. 589, 590) oder beträchtlich höher (Fig. 584) und unten durch eine dünne, zuweilen nach innen eingebuchtete Basalplatte abgeschlossen (Fig. 584, 590). Bei einigen Exemplaren [var. quadripartita, Fig. 584] fehlt ein Abdomen, bei einem Exemplar (var. quinquepartita, Fig. 589, 590) schließt sich jenseits der Basalplatte ein kragen artiges, schräg abgestutztes Ansatzrohr an, dessen Rand mit etwa 35 kurzen, bandförmigen (im Präparat wahrscheinlich abgebrochenen) Zähnen besetzt ist.
Das Innenskelett dürfte wohl, ähnlich demjenigen von Peromelissa denliculata (Taf.LXXIV, Fig. 591), im wesentlichen einem basalen Tripodium entsprechen. Von einem an der Grenze zwischen Cephalis und Thorax gelegenen Centrum strahlen drei reich verzweigte Querbalken aus, von denen einer mit zahlreichen, unregelmäßigen Aesten den Zwischenlobus umspinnt (Fig. 590, links). Diese 3 Aeste sind wohl als die Cortinarfüße des Tripodiums zu betrachten (vergl. Rep., p. 891; cortina = Dreifuß). Außerdem gehen von dem Centrum ab ein vertikaler, nach oben gerichteter, ebenfalls stark verzweigter Balken, welcher vielleicht einem Teil des Sagittalringes bei anderen Nasseilarien entspricht, und ein nach abwärts gerichteter thorakaler Achsenstab, welcher sich in ganz ähnlicher Weise bei Peromelissa dentiatlata wiederfindet (Fig. 591).
Die von Nahrungsmassen umgebene, mehrlappige Centralkapsel ist teils in den Logen der Cephalis, teils im Thorax gelagert (Fig. 584). Genaueres über die Zahl und Anordnung der Centralkapsellappen konnte ich wegen der Nahrungsmassen bei dieser Form nicht ermitteln.
Längster Durchmesser der Schale 0,11 (var. quadripartita) bis 0,13 mm (var. quinquepartita), Breite: 0,09 mm. | | Haecker 1908 | Botryopyle? antarctica
From the material collected in antarctic waters by the "Valdivia" in 1898-99, Haecker (1907) described this species for which he erected the genus Saccospyris within the subfamily Rhodospyrinae. Campbell (1954) indicated that Saccospyris is a junior synonym of Ehrenberg's genus Haliphormis. However, examination of this species from the B.A.N.Z.A.R.E. material shows that it does not belong among Haeckel's Triospyrida (superfamily Triospyridicae according to Campbell, 1954) but rather among his Botryodea (superfamily Cannobotrydicae according to Campbell). Although Haecker apparently took considerable pains to determine the internal structure of this form, his description and figures are somewhat inadequate. The following description (and text-figure 13) are based on a close examination of several specimens, which varied in some details but in all of which the general plan of the internal structure was similar. Externally, the shell exhibits five main parts :—the thorax (A) which in some specimens is closed distally, a larger (B) and a smaller (C) cephalic lobe, an inconspicuous chamber (D) between A and C, and some rather irregular shell material (E) laterally from D. Pores which are generally regular in form and arrangement connect the chambers of A and B, B and C, C and D, D and A, and D and B. Between A and B are two large, constant pores (a, a') and usually one or two smaller pores (b, b'). An almost constant feature of the wall separating B and C is a pair of pores c and c', and in some specimens other pores also penetrate this wall. C communicates with D by a simple opening (d), which is constricted by a ledge (e). Between the chamber D and A are four main pores, two larger (f, f') and two smaller (g, g'), and a number of peripheral pores (h) which are inconstant in size and arrangement. Near the junction of the bars separating f, f', g and g' arises a spine (k) which projects downward into the thorax A. Two large pores (j, j') connect D with B. Close to the wall of the chamber D, bars extend between C and A.
Thus the structure is more complicated than indicated by Haecker's description, and comparison with that described by Bütschli (1882, 520, PI. 33, figs. 27a-c) for Lithobotrus geminata Ehrenberg leaves little doubt that the antarctic form belongs among the Cannobotrydicae. Haeckel's descriptions of members of this group are inadequate, and it is difficult at present to assign this species to a genus with any confidence. Botryopyle ? antarctica may be identical with Bisphaerocephalus minutus Popofsky (1908, 284-285, PI. 33, fig. 9), described from a single specimen collected in Antarctic waters.
Total length of shell of B. ? antarctica 80-155 µ, its maximum breadth 70-100µ. Measurements based on 11 specimens from Sta. 30, 3 from Sta. 42, 9 from Sta. 47, 24 from Sta. 94, 17 from Sta. 97 and 5 from Sta. 103.
This species occurs in both the American and Indian Ocean sectors of Antarctic waters, as well as at several widely separated localities in the northern Pacific. It has not been found in the tropical parts of the Pacific and Indian Oceans. Thus it appears to have a cold-water bipolar distribution. | | Riedel 1958 | Saccospyris antarctica
Shell irregularly cylindrical, with ridges on surface, surface pierced by a few irregular pores. Chambers of first segment barely noted externally as irregular swellings. Antecephalic and cephalic chambers approximately uniform in structure of walls and in size — cephalic chamber just larger than antecephalic. Needles D, Lr and Ll disposed inside shell slightly obliquely to MB, but basal plate is entire. Second chamber of shell with smoother wall than first, particularly in lower part, has greater number of pores. Second segment in adult specimens with saccular termination; largest pores lying in lower part of second segment.
Dimensions: length of first segment 30-50 µ of second segment 80-12µ overall length of shell 110-160µ measurement of shell along axis of MB up to 100µ measurement in perpendicular direction 70-80µ.
Location. Found in sample from the 4,000-5,000-m depth (at station 147 of the "Valdivia") by Haecker (1907, 1908). Found by Riedel (1958) in Antarctic sediments at stations 30, 42, 47, 94, 97, and 103 of BANZARE. Encountered in our material in sediments of almost all the Antarctic stations. Shells of this species usually constitute less than 1% in shallow- water sediments, in deepwater sediments up to 2.5% of the total number. Not found in sediments of temperate and tropical zones (Figure 92, II).
Note. Judging from his description Riedel (1958) took this species to be far wider, and included in it representatives of the following species [Saccospyris conithorax] | | Petrushevskaya 1967 |
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