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Corocalyptra craspedota (Jørgensen, 1900)

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Theocalyptra craspedota:
Cephalis hoch halbkugelförmig, 0.019mm hoch, 0.031 breit, mit kleinen, ungleich grossen, rundlichen oder etwas länglichen, sehr dickwandigen, 0.002 bis 0.004mm breiten poren und zwei divergirenden, breiten, dreischneidigen hörnern (in dem gefundenen exemplare war das grösste abgebrochen wahrscheinlich viel länger als der durchmesser des cephalis).

Thorax kegelförmig, 0.090mm hoch unten 0.153mm breit. Die poren sind im oberen theile ungleich gross, dickwandig, nach unten allmählich grösser und mehr gleichgross, am unteren rand des thorax fast vierckig, ziemlich regelmässige reihen bildend, hier bis 0.011mm breit.

Abdomen einen flachen, ausgebogenen, dünnwandigen saum bildend mit einer einzigen reihe regelmässiger, viereckiger maschen, die ungefähr 0.009mm breit sind.
Jørgensen 1900
Clathrocyclas craspedota:
The abdomen is a narrow, flat, projecting brim, on well developed specimens having two or three regular, circular rows of meshes, the inner row with small pores. The free side-walls of a ring of meshes under development will have the appearance of a regular circle of short, radial spines on the abdominal brim.

The same spines are present as in the preceding genus [Androcyclas gamphonycha]. The three basal spines protrude similarly as fine needles in the upper part of the thorax (the dorsal spine, A, farther down than the others). The apical spine, D, also here protrudes with a broad three-edged topsword directed upwards and somewhat backwards. The ventral, sagittal spine protrudes upwards and forwards (ventrally) with a similar, three-edged topsword, which is, however, a. little smaller and points obliquely forwards.

Refer for further details to Jørgensen, 1. C. [1900].

As the incompletely developed abdomen often exhibits a marginal brim of regular, short spines like those Haeckel draws for species of the genus Clathrocyclas, subgenus Clathrocycloma HCK. (L. 86, pls. 58, 59), I have thought it best to refer my species to this genus where it seems to have its natural place. In doing so, I also think that Clathrocycloma HCK. will be found to have the three basal spines protruding from the upper part of the thorax like fine needles.

If these needles are overlooked or absent, and no notice is taken of the spines on the brim of the abdomen, the species according to Haeckel’s system will be a Theocalyptra.

Halicalyptra ? cornuta Bail. = Theocalyptra c. Haeckel is quite impossible to determine from the very imperfect illustration, given by Bailey. After this drawing it has only cephalis and thorax.

Frequent, though never numerous.

Distribution: On the west coast of Norway, very rare. In surface samples 2/2 1901, off Sundmøre, and 13/2 off Lofoten (cfr. Above under Cladoscenium tricolpium p. 134). If this species be Cleve’s Theocalyptra cornuta, it has been found at grate depths at some places in the North Atlantic right up to the north west coast of Spitzbergen, and at scattered places in the western part of the North Atlantic. Most probably boreal oceanic.
Jørgensen 1905


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