Heterohelix
| Cassigerinella Temporal range: Santonian - Late Paleocene |
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|---|---|
| Scientific classification | |
| Domain: | Eukaryota |
| (unranked): | SAR |
| (unranked): | Rhizaria |
| Superphylum: | Retaria |
| Phylum: | Foraminifera |
| Class: | Globigerinida |
| Order: | Globigerinina |
| Superfamily: | Heterohelicoidea |
| Family: | Heterohelicidae |
| Genus: |
'Heterohelix Ehrenberg, 1843 |
Heterohelix is a genus of globigerid forams belonging to the family Heterohelicidae of the superfamily Heterohelicoidea and the suborder Globigerinina, which belongs to the order Globigerinida Its type species is Textilaria americana.
The genus name is Greek from heteros and helix (ήλιξ, of the sun).
Its fossil range is from Santonian (Late Cretaceous up to the early Danien or early Paleocene.
Heterhelix includes species with double cones, in occasion with a small flat spiral state.
There is an old controversy between the status of Heterohelix and Spiroplecta, and which the author of other genera apparently used the definition to the same species style, in the first case, named Textilaria americana, and the second Spiroplecta americana. For that reason, given which was the first number of that priority, Spiroplecta which later became a synonymy of Heterhelix. Other genera which described with a planispyllated stage, which was clearly more developed in Spiroplecta which had 5 to 6 chambers, where in Heterohelix which had 2 to 3 chambers. Different authors which brought the generic number Guemnbelina whose type species is Heterohelix globulosa, for grouping other morphological, all of them two legged, and considered for the presence of a planispylliated stage, with an expression of an alternation of generations,being the planispyllated stage of microspheric forms. After, it has been widely accepted with Spiroplecta and Buembelina as subjective synonyms of Heterohelix. Classifications that include Heterohelix in the order Heterohelicida.
Heterohelix includes species with a mode of planktonic life, of latitudinal distribution, in tropical and temperate waters, and pelagic numbers of superficial and intermediate waters (mid-epiplagic and late-mesoplagic).
Species in Heterohelix include:
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