Lamprocyclas maritalis group
Description - Add description
|Benson, 1966, p. 475-479; pl. 32, figs. 10-12; pl. 33, fig. 1:|
Lamprocyclas maritalis Haeckel
Lamprocyclas maritalis Haeckel, 1887, Challenger Rept., Zool., vol. 18, pp. 1390-1391, Pl. 74, figs. 13, 14; Haecker, 1907, Archiv für Protistenkunde, vol. 10, p. 126, fig. 12; 1908, Deutsche Tiefsee-Exped., vol. 14, pp.445-456, Pl. 85, figs. 594, 595.
Lamprocyclas maritalis Haeckel antiqua Riedel, 1953, Journ. of Paleo., vol. 27, no. 6, pp. 811-812, Pl. 85, fig. 4.
?Lamprocyclas intermedia Haecker, 1908, Deutsche Tiefsee-Exped., vol. 14, p. 455, Pl. 84, fig. 585, text figs. 88a-c, 89.
Test similar to Anthocyrtidium cineraria but with the addition of an abdominal joint. Cephalis the same as in Anthocyrtium oxycephalis and A. cineraria except larger, with thicker wall, generally with pores surrounded by hexagonal frames, and in many specimens open at the top. Apical horn straight (in one specimen ascends dorsally), generally three-bladed but four-bladed at its base in a few specimens; in a few tests the junction of the two lateral blades is smooth, not angular, forming a ventral groove in the horn, semicircular in section. Vertical spine generally absent. Four to six collar pores present, six if the secondary lateral bars are free within the cephalic cavity instead of occurring as ribs at the base of the dorso-lateral cephalic lobes. Dorsal and primary lateral bars extend as thoracic ribs, often raised, that generally project as short spines or thorns (2-16 µm in length) above the base of the thorax. Thorax separated from cephalis by a distinct change in contour, generally thick-walled, campanulate, separated from abdomen by a distinct annular constriction occupied by a smooth internal septal ring. Abdomen truncate-conical, broader than thorax, with at its base a sharp inward curvature that terminates in a constricted mouth surrounded by a hyaline peristome surmounted by peristomal tooth-like spines. Subterminal spines arise from the broadest part of the abdomen just above its sharp inward basal curvature. Pores of thorax and abdomen arranged hexagonally in vertical rows that are continuous between the joints. Pores subcircular to subpolygonal, increase gradually in size distally, separated by heavy, intervening bars surmounted by hexagonal frames in various stages of development. Surface of thorax and abdomen generally rough. Subterminal spines divergent, less conspicuous than peristomal spines, generally heavy, pyramidal to three-bladed, short, more nearly like heavy thorns, generally present but in some specimens only rudimentary, variable in number from 5 to 15. Peristomal spines variable in number from absent to 20 or more, ranging from short pyramidal or three-bladed thorns to relatively long, lamellar, triangular to rectangular, tooth-like spines, in several specimens bifurcated distally; they generally extend vertically downward but are convergent inward in some specimens. A few specimens observed without subterminal spines, hyaline peristome, and peristomal spines.
Measurements; based on 21 specimens from stations 27, 34, and 46: length of test (including apical horn) 191-308 µm, of apical horn 37-85 µm, of cephalis (top of ventral face to median bar) 31-47 µm, of thorax 49-74 µm, of abdomen 44-108 µm; breadth of cephalis 37-49 µm, of thorax 98-135 µm, of abdomen 121-185 µm; length of subterminal spines 6-12 mm, of peristomal spines 2-41 µm.
Remarks. This species is variable in the thickness of its thoracic and abdominal walls, the degree of development of polygonal frames surrounding the abdominal and thoracic pores, and in the details of the terminal and subterminal spines. The terminal spines arising from the hyaline peristome vary in number, length, and shape, ranging from short, triangular, flat, tooth-like spines in some specimens to relatively long, lamellar or conical spines which branch distally, especially in tests with thick shell walls; the spaces between the latter type of spines appear to be large rudimentary pores that are not completely closed distally by the branches originating from the spines. No specimens were observed with a second abdominal joint, although the rudimentary pores suggest such a joint. The subterminal spines are three-bladed and sharply pointed, variable in size, and absent in a few specimens.
This species differs very little from Haeckel's original definition (1887, pp. 1390-1391) except that no double-contoured pores were observed. Haecker (1908, p. 456) also did not observe this feature. It differs from L. maritalis antiqua Riedel in having slightly larger pores which are more regularly arranged than those shown in Riedel's illustration (1953, Pl. 85, fig. 4). Haecker (1908, p. 455) states that L. intermedia Haecker differs from L. maritalis only in the presence of a thinner shell wall and poorly developed terminal and subterminal spines, features which are subject to intraspecific variation. It appears that L. intermedia Haecker should be placed in synonymy with L. maritalis, but without study of Haecker' s original material the synonymy is tentative because Haecker's illustration of the latter species is poor.
Distribution. In the Gulf this species is rare but occurs at all stations as far north as 184 but is absent north of this station. It has a slightly greater frequency in the southern Gulf, south of approximately 26 degrees N latitude; therefore, it is probably a Pacific oceanic form. It does not increase at stations located within regions of known upwelling.
Haeckel (1887, p. 1391) reported its occurrence from the central Pacific at "Challenger" station 272. Haecker (1907, p. 126; 1908, p. 456) observed it in the northern Indian Ocean. Riedel (1953) reported L. maritalis antiqua from a late Tertiary assemblage in calcareous sediment on the island of Rotti, near Timor; therefore, the subspecies he defined may represent a much older form than the Recent examples of L. rnaritalis. L. intermedia was observed in the southern as well as northern Indian Ocean and also in the Gulf of Guinea and Guinea Stream off the west coast of Africa (Haecker, 1908, p. 455). Apparently L. maritalis is confined to Recent tropical seas.
|Benson, 1983, p. 504:|
Lamprocyclas maritalis maritalis Haeckel
Remarks. Lamprocyclas maritalis maritalis was distinguished from L. m. polypora on the basis of having ten or fewer pores on the half equator of the abdomen, a thicker abdominal wall with pores set in polygonal frames, generally smaller abdominal dimensions, and, typically, a well-developed hyaline peristome with numerous tooth-like spines. Some specimens with very broad abdomens (Benson, 1966, pl. 33, fig. 1) may belong to L. m. ventricosa (Nigrini, 1968). L. m. maritalis is the dominant member of this group in the samples examined.