Halistylus
Halistylus is a genus of very small sea snails, marine gastropod mollusks in the family Trochidae, the top snails.[1]
| Halistylus | |
|---|---|
 | |
| Two shells of Halistylus columna | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Gastropoda |
| Clade: | Vetigastropoda |
| Order: | Trochida |
| Superfamily: | Trochoidea |
| Family: | Trochidae |
| Genus: | Halistylus Dall, 1890 |
| Type species | |
| Cantharidus columna Dall, 1890 | |
Description
The small, polychromatic shell has a cylindrical shape. It is holostomatous, i.e. the aperture is rounded or entire, uninterrupted by the siphonal canal, notch, or by any other extension. The operculum is multispiral and coriaceous. There is no spiral sculpture. Such a cylindrical shape is rather uncommon in the family Trochidae. But the belonging of this genus to this family is certified by the shell structure, the pearly aperture and anatomical features.[2]
This genus was previously considered a subgenus of the genus Cantharidus Montfort
Species
Species within the genus Halistylus include:
- Halistylus columna (Dall, 1890)
- Halistylus genecoani McLean, 1984
- Halistylus pupoideus (Carpenter, 1864)
- Species brought into synonymy
- Halistylus circumstriatus Pilsbry, H.A., 1897: synonym of Halistylus columna (Dall, 1890)
- Halistylus pupoides: synonym of Halistylus pupoideus (Carpenter, 1864)
gollark: I suspect SQLite would lose out somewhat in storage efficiency, but it could plausibly be faster for many things at runtime.
gollark: It's less complex for everyone interacting with it, since they can just... use SQLite, which has bindings for everything, instead of "zimlib". And by "efficiency" do you mean "space efficiency" or "lookup efficiency"? Because, as I said, SQLite would probably only add a few bytes per directory entry row, which is not a significant increase.
gollark: SQLite's overhead is pretty low, and the majority of the filesize is from the binary blobs which would remain the same in each.
gollark: It's less complex for them as the code is already there and written with a nice API, and "less efficient" how? Slightly more space on headers?
gollark: You could easily store the directory entry bits as an SQLite table.
References
- Halistylus Dall, 1890. Retrieved through: World Register of Marine Species on 4 July 2011.
- Dall, W.H. (1890) Scientific results of explorations by the U.S. Fish Commission Steamer Albatross. No. VII – Preliminary report on the collection of Mollusca and Brachiopoda obtained in 1887–88. Proceedings of the United States National Museum, 12, 219–362, pls. 5–14
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