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Larcopyle pylomaticus
(Riedel, 1958)
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Description - Add description
Spongurus pylomaticus
Shell subcylindrical or elongate ellipsoidal, approximately twice as long as broad. An inner, densely spongy core is surrounded by a narrow mantle of less dense meshwork. Entire surface usually sparsely covered with bristle-like spines, which in many specimens tend to be longer at the two poles of the main axis. At one pole is a pylome, usually surrounded by short, irregular teeth. Length 150-255µ, breadth 78-125µ. Length of surface spines 5-40µ (usually broken off). | | Riedel 1958 | Spongurus pylomaticus
Skeleton cylindrical, approximately twice as large as wide. Skeleton constructed of dense spongy tissue; just possible to distinguish striation on periphery corresponding to radial needles. Radial needles extending to exterior (often broken off), distributed irregularly: large number on poles of shell, where they are usually longer. In adult specimens spongy mass surrounded externally by thin "mantle" which has more formed pores than growing spongy tissue. Mantle not formed at one pole of shell where opening is present, in some degree corresponding to pylome. margin of pylome usually encircled by short irregular spikes. Age changes appear as absence of mantle in young specimens - these are somewhat constricted in middle and expanded at ends; radial striation more marked in them.
Dimensions: length of shell up to 225µ, width up to 125µ. Variation of dimensions often explained by constant growth of spongy shell. | | Petrushevskaya 1967 | Spongurus(?) pylomaticus
Cylindrical skeleton is up to 225µ long, up to 125µ broad. No patagium. Gown is common and covers the entire skeleton.
| | Petrushevskaya 1975 | Larcopyle pylomaticus
See also original description by Riedel (1958). The sub-cylindrical or elliptical shell is about 130 µm long and has a dark appearance in the light microscope. The more or less spongy outer wall consists of small pores which are arranged close together and lack frames. In Pliocene specimens the inside of the shell is filled with spongy meshwork, whereas older specimens show a double (?) spiral with constantly spaced whorls. These, in turn, appear to intergrade with coeval Late Miocene specimens of L. augusti. The shell has a well-developed, wide pylome with teeth. | | Lazarus et al 2005 |
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