|Pourtalesiid sea urchins (Echinodermata: Echinoidea) of the northern Mid-Atlantic Ridge|
Mironov, A.N. (2008). Pourtalesiid sea urchins (Echinodermata: Echinoidea) of the northern Mid-Atlantic Ridge, in: Gebruk, A.V. (Ed.) Benthic fauna of the northern Mid-Atlantic Ridge: results of the MAR-ECO expedition. Marine Biology Research, 4(1-2): pp. 3-24
In: Gebruk, A.V. (Ed.) (2008). Benthic fauna of the northern Mid-Atlantic Ridge: results of the MAR-ECO expedition. Marine Biology Research, 4(1-2). Taylor & Francis: UK. 163 pp., more
In: Marine Biology Research. Taylor & Francis: Oslo; Basingstoke. ISSN 1745-1000, more
|Also published as |
Adaptations; Burrowing organisms; Geographical distribution; Morphology (animal); New genus; New species; Echinodermata [WoRMS]; Echinoida [WoRMS]; Echinoidea [WoRMS]; Pourtalesiidae A. Agassiz, 1881 [WoRMS]; AN, Mid-Atlantic Ridge [Marine Regions]; Marine
Five species of deep-sea pourtalesiid echinoids were collected by the RV G.O. Sars MAR-ECO expedition to the northern part of the Mid-Atlantic Ridge: Solenocystis imitans new genus, new species, Echinosigra phiale (Thomson, 1872), Echinosigra (Echinogutta) fabrefacta Mironov, 1974, and two unidentified species of Pourtalesia. Three types of plastron plating are distinguished within the family Pourtalesiidae; in Solenocystis new genus the plating is similar to that in Spatagocystis, a genus known only from the deep-sea Antarctic. Each of three groups with distinctive plastron plating shows a continuous morphological gradation from a less elongated test without subanal rostrum to an extraordinarily elongated test with large rostrum and wide subanal fasciole; the ratio width/length of test varies from 0.86 to 0.12. Some morphological characters of the pourtalesiids are regarded as adaptations to burrowing and appear to be correlated with test elongation. The family is represented in the northern Atlantic only by 'advanced' genera (Echinosigra, Pourtalesia and Solenocystis) with very elongated tests.