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Tripophaenoscenium laimingi Campbell and Clark, 1944

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Shell very large and striking; apical horn 0.5 total length, formed by midvertical union of three erect, equal, triangular blades, wide bases of which arise along upper sides of blunted, pointed shell-reticulum, distal ends of blades sharply pointed, mak­ing a strong spikelike horn, each blade fairly similar, with two accessory, projecting spikes below middle and with two pores in hyaline blade, one of pores large and oval, other small and circular, position of spikes and pores not exactly same on opposite blades; shell generally conical (77° in upper 0.5, later 55°, and finally 30° below level of origin of feet, which level is widest of shell as a whole; thence shell reduced as a funnel- shaped section of 55° to apertural margin); apertural section about 0.25 length of shell in length; feet three, equal, equidistant, gracefully incurved like three great claws or prongs; these three legs as long as shell itself, formed of three blades with sharp tips, outermost with an acromion in upper 0.5 of length, and distally conical and con­sistently reduced in diameter as extended distally, origin on side of shell a broad, triangular, pore-bearing, transverse plate, but ridgelike blade or acromion extends up on outside of shell toward apex although lost before it reaches that point; from middle of side of shell arise three strong, horizontal spikes shorter than legs (probably about 0.5 length of latter), spikes alternated with legs in position, triangular in section with thickened blades, distally sharp-pointed, and proximally merged into shell-reticulum; apertural margin badly broken in our specimen but probably with a thick transverse ring; internally shell provided with a columella, this structure consisting of a vertical rod connected at one end with base of apical horn and at other end, in shell-cavity, at a common center with three transverse rods which connect with three horizontal spikes and also with three alternated, radial rods connected with feet, rods all provided with side-branches which connect with shell framework at intervals; pores of several sizes freely scattered, larger and smaller side by side, none of them, however, very tiny, in shape generally subcircular although some are subquadrangular, tear-shaped, or other­wise modified, pores with high, thin, projecting, needle-shaped sepaloid points produced from framework around them giving whole shell a burrlike surface; framework of thin bars so that shell is a loose network and almost transparent. Length, total (of tipped specimen), 470 µ, of legs (across arc), 150µ diameter of aperture, 230 µ, of pores, 6.6-22.0 µ.
Tripophaenoscenium laimingi n.sp. is one of real "finds" of this collection and is strikingly different from any other species in many characters. Burry surface, long, bladed horn, giant clawlike legs, and thin framework suggest strongly that it was a pelagic species. Within cavity of lower portion of shell in figured specimen is a small coin-shaped spumellarian with small peripheral spines and a regular network of subhexagons. No others like it have been found free, and consequently it is not identified.
Campbell & Clark 1944











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