Adoneis G.W.Andrews & P.Rivera, 1987

Holotype species: Adoneis pacifica G.W.Andrews & P.Rivera

Original publication and holotype designation: Andrews, G.W. & Rivera, P. (1987). Morphology and evolutionary significance of Adoneis pacifica gen. et sp. nov. (Fragilariaceae, Bacillariophyta), a marine araphid diatom from Chile . Diatom Research 2(1): 1-14.

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Description: Growth habit not known. Frustules linear in girdle view with flat valves. Valves broadly lanceolate with smooth convex sides and rounded, sometimes capitate, apices. Valve face flat, mantle narrow. Striae uniseriate, 6-8 in 10 &m, radiating in slightly curved transverse rows from narrow axial area. Areolae round, vela of the rota type located near outer surface of valve. One row of areolae on mantle, continuous around apices. Pseudocellus of fine pores at both apices, pores in curved radial rows following same trend as areolae. Usually 4 rimoportulae per valve; one in each pore field and one near center of each lateral margin, sometimes only on one margin. Rimoportulae in the pore fields slightly eccentric. Internal openings of rimoportulae usually a single slit, oriented parallel to valve margin; outer opening a simple pore. An irregular row of small granules along valve-mantle boundary. Cingulum consists of a copula, split at one apex. Differs from Rhaphoneis in possession of lateral rimoportulae, and location of apical rimoportulae inside pore fields, rather than between fields and remainder of the valve. Differs from Diplomenora and Perissonoe,/i> in shape of valve; differs from Delphineis in possession of apical pore fields and of lateral rimoportulae.Growth habit not known. Frustules linear in girdle view with flat valves. Valves broadly lanceolate with smooth convex sides and rounded, sometimes capitate, apices. Valve face flat, mantle narrow. Striae uniseriate, 6-8 in 10 &m, radiating in slightly curved transverse rows from narrow axial area. Areolae round, vela of the rota type located near outer surface of valve. One row of areolae on mantle, continuous around apices. Pseudocellus of fine pores at both apices, pores in curved radial rows following same trend as areolae. Usually 4 rimoportulae per valve; one in each pore field and one near center of each lateral margin, sometimes only on one margin. Rimoportulae in the pore fields slightly eccentric. Internal openings of rimoportulae usually a single slit, oriented parallel to valve margin; outer opening a simple pore. An irregular row of small granules along valve-mantle boundary. Cingulum consists of a copula, split at one apex. Differs from Rhaphoneis in possession of lateral rimoportulae, and location of apical rimoportulae inside pore fields, rather than between fields and remainder of the valve. Differs from Diplomenora and Perissonoe,/i> in shape of valve; differs from Delphineis in possession of apical pore fields and of lateral rimoportulae.

Information contributed by: C. Sancetta. The most recent alteration to this page was made on 2017-08-14 by M.D. Guiry.

Taxonomic status: This name is of an entity that is currently accepted taxonomically.

Most recent taxonomic treatment adopted: Cox, E.J. (2015). Coscinodiscophyceae, Mediophyceae, Fragilariophyceae, Bacillariophyceae (Diatoms). In: Syllabus of plant families. Adolf Engler's Syllabus der Pflanzenfamilien. 13th Ed. Photoautotrophic eukaryotic algae Glaucocystophyta, Cryptophyta, Dinophyta/Dinozoa, Heterokontophyta/Ochrophyta, Chlorarachniophyta/Cercozoa, Euglenophyta/Euglenozoa, Chlorophyta, Streptophyta p.p. (Frey, W. Eds), pp. 64-103. Stuttgart: Borntraeger Science Publishers.

Comments: Found in marine plankton samples from coastal zone of Chile. Hasle & Syvertsen (1997: 247-248) record this genus as being a member of the Family Raphoneidaceae (Forti, 1912).