| Home> Cenozoic> Holocene (Recent)> Gulf of California>
 

List species

Lophocorys polyacantha Popofsky, 1913

Description - Add description

Benson, 1966 (partim.), p. 494-496; pl. 34, fig. 3, (not 1-2):

Lophocorys polyacantha Popofsky

Lophocorys polyacantha Popofsky, 1913, Deutsche SŘdpolar-Exped., vol. 14, pp. 400-401, text fig. 122.
?Artopilium undulatum Popofsky, 1913, op. cit., pp. 405-406, Pl. 36, figs. 4, 5.

Test with 3-5 joints that increase in breadth distally and are separated by broad constrictions without septal rings. Individual joints in most tests with rounded shoulders or at least broader proximally and nearly cylindrical distally.
Forms identical with Lophocorys polyacantha Popofsky and Artopilium undulatum Popofsky are included together because specimens corresponding to the latter are rare in the Gulf but are similar to the former in shape of joints and basic structure of the cephalis. The relationships between these two forms are not clear, and further taxonomic study of them is needed.
Tests corresponding to the former species have large, subcircular to hexagonal pores that increase in size distally and are arranged hexagonally in longitudinal rows. Cephalis subspherical to subcylindrical, relatively large, with subequal, hexagonal pores except for a pair of larger dorsal pores on either side of the apical bar in the wall of the cephalis; with a surface ranging from smooth to one with several, scattered, thin, conical spines. A conical to three-bladed apical spine ascends dorsally from its origin on the dorsal face of the cephalis. A short vertical spine generally inconspicuous. Four collar pores present. Dorsal and primary lateral bars extend as thoracic ribs that are prolonged as short, thin spines (3-12 Ám) in most specimens. In several tests there are
1 to 2 joints below the cephalis, but the distal joint is long, cylindrical to truncate-conical, and without constrictions. Surface of a few tests smooth, but in most tests with scattered thin, conical spines (2-22 Ám). Mouth of test not constricted; terminal margin incomplete.

Measurements; based on 14 specimens from stations 46, 60, 64, 81, 93, 106, and 151: maximum length of test 111-200 Ám, maximum breadth 74-117 Ám; length of cephalis 21-34 Ám, breadth 25-34 Ám; length of apical spine or horn 2-37 Ám.

Distribution. This species or species-group is rare but nearly cosmopolitan in the Gulf. It is absent at stations 27, 90, 95, 99, 130, 191, 194, and all those to the north. Its absence at marginal localities and its slightly greater frequency in the axial portion of the Gulf indicate its preference for more nearly oceanic, offshore waters. It undergoes no significant fluctuations in its frequency throughout the Gulf.
This species or species-group is widespread in Recent tropical seas. Lophocorys polyacantha Popofsky and Artopilum undulatum Popofsky are both reported from the tropical Atlantic Ocean, the latter from the tropical Indian Ocean as well.
Benson 1966
Benson, 1983, p. 505:

Lophocorys polyacantha Popofsky group

Remarks. This group is characterized by undulatory constrictions in the distally expanding abdomen and by a relatively large cephalis. Variations in members of this group are the number of abdominal constrictions, the size and shape of pores, and the degree of spininess of the cephalis (smooth surface to one with several scattered, thin, conical spines; with or without apical horn).
Benson 1983


Description

 

Images

 

Synonyms

 

References

 

Distribution

 

Discussion / Comments

 

Web links