| 词条 | Daphnella ryukyuensis |
| 释义 |
|taxon =Daphnella ryukyuensis |image = Daphnella ryukyuensis 001.jpg |image_caption= Original image of a shell of Daphnella ryukyuensis |authority = F.S. MacNeil, 1960 |synonyms_ref = |synonyms = |display_parents = 3 }}Daphnella ryukyuensis is an extinct species of sea snail, a marine gastropod mollusk in the family Raphitomidae.[1] DescriptionThe length of the shell attains 30 mm. (Original description) The shell is of medium size, medium to moderately slender, lymneiform. The whorls are flattened in the young state but rounded in adults. The protoconch consists of 2¾ whorls, the first very small and smooth, the remainder microscopically diagonally cancellate, the diagonal lines being rough and irregular. The aperture is of medium width. The outer lip is thin and gently rounded. The anal sinus is shallow, located nearly adjacent to the suture. The sculpture on the juvenile whorls consists of a row of small rounded beads set on a low shoulder directly beneath the suture and with weak spiral lines below. The adult sculpture consists of very faint spiral lines, somewhat more evident and coarser on the lower part of the body whorl and columella. [2] DistributionFossils of this species were found in Miocene strata on the Ryukyu Islands References1. ^ Worldwide Mollusc Species Data Base:Daphnella ryukyuensis 2. ^ [https://pubs.usgs.gov/pp/0339/report.pdf MacNeil, Tertiary and Quaternary Gastropoda of Okinawa; USGS Geological Survey Professional Paper 339, 1960] External links{{Taxonbar}}{{DEFAULTSORT:Daphnella Ryukyuensis}} 2 : Daphnella|Gastropods described in 1960 |
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