Longinebela penardiana (Deflandre, 1936)
Nebela penardiana Deflandre, 1936
Diagnosis: shell usually brownish, pyriform or elongate, slightly compressed laterally and with small lateral margins which do not extend around the aboral region, but small lateral pores are usually present at a distance of one-third of the body length from the aperture. Shell composed of a mixture of oval, circular and quadrangular shell plates. Aperture oval, sometimes concave from a lateral aspect, and surrounded by a collar of organic cement.
Dimensions: Length of shell 115-180 µm; width of shell 65-80 µm; depth of shell 37-54 µm; diameter of aperture 23-34 µm.
Remarks: This species is distinguished from P. marginata by being narrower and having less pronounced lateral margins, and from L. tubulosa and G. galeata in size and shape. One variety of L. penardiana is noted by Deflandre (1936) in his review of the genus. For distinguishing characters from L. ampulla see that description.