Pteromonas Seligo, 1887

Holotype species: Pteromonas aculeata Lemmermann

Original publication: Seligo, A. (1887). Untersuchungen über Flagellaten. In: Beiträge zur Biologie des Pflanzen. Bd 4. (Cohn, F. Eds), pp. 145-178. Berlin: Duncker & Humblot.

Description: Unicellular, biflagellate and uninucleate algae with protoplast contained in a firm, strongly compressed lorica with smooth, roughened or spiny surface. Innarrow side view, lorica obviously consists of two equal sections with contact margins closely adpressed and sometimes raised, forming an indistinct keel. In broad front view, lorica globose or oval, with entire, angled or undulate lateral margins. Anterior end rounded or slightly retuse, or subrectangular and with or without distinct extensions at the angles. In vertical view, protoplast usually in close contact with outer margins of lorica, thelorica with straight or curved projections extending beyond each pole. In broad front view, protoplast not in close contact with lorica except at anterior end. Protoplast pyriform, ovoid or globose, and compressed. Flagella emerge from separate openings at anterior of lorica. Chloroplast principally cup-shaped with 1-several pyrenoids and usually with a stigma. Two contractile vacuoles present at base of flagella. Asexual reproduction by division into 2 or 4 daughter cells, these released upon separation of two halves of mother cell lorica. Akinetes reported. Sexual reproduction isogamous, producing a quadriflagellate planozygote. Mature zygote globose, with a thickened, usually smooth wall. Meiosis apparently zygotic.

Information contributed by: G.E. Dillard. The most recent alteration to this page was made on 2024-02-19 by E.A. Molinari Novoa.

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

Gender: This genus name is currently treated as feminine.

Most recent taxonomic treatment adopted: Pentecost, A. (2002). Order Volvocales. In: The Freshwater Algal Flora of the British Isles. An identification guide to freshwater and terrestrial algae. (John, D.M., Whitton, B.A. & Brook, A.J. Eds), pp. 303-327. Cambridge: Cambridge University Press.

Comments: Pteromonas is cosmopolitan in freshwater. Individual species generally infrequently encountered and, in many cases, known only from type localities. Eighteen species are well described and distinguished based on position and relative size and shape of the lorica wings, the shape of the lorica in outlie, the form of ornamentation, if any, of the lorica and the number and relative position of the pyrenoids. Over 25 additional species described, mostly by Skvortsov; in most cases, descriptions quite incomplete, and species of doubtful taxonomic validity. With light microscopy, lorica of Pteromonas spp. appears as an opaque, generally U-shaped wing. Ultrastructurally, lorica of P. tenuis Belcher et Swale and P. angulosa (Carter) Lemmermann double layered, with each layer marked with a pattern of denser, slightly raised ridges enclosing more or less hexagonal areas. In P. protracta Lemmermann (suggested for synonymy with P. aculeata Lemmermann by Ettl) lorica composed of two layers, a finely granular outer layer with hexagonal surface pattern andan inner fibrillar layer.

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Contributors
Some of the descriptions included in AlgaeBase were originally from the unpublished Encyclopedia of Algal Genera, organised in the 1990s by Dr Bruce Parker on behalf of the Phycological Society of America (PSA) and intended to be published in CD format. These AlgaeBase descriptions are now being continually updated, and each current contributor is identified above. The PSA and AlgaeBase warmly acknowledge the generosity of all past and present contributors and particularly the work of Dr Parker.

Descriptions of chrysophyte genera were subsequently published in J. Kristiansen & H.R. Preisig (eds.). 2001. Encyclopedia of Chrysophyte Genera. Bibliotheca Phycologica 110: 1-260.

Linking to this page: https://www.algaebase.org/search/genus/detail/?genus_id=43460

Citing AlgaeBase
Cite this record as:
E.A. Molinari Novoa in Guiry, M.D. & Guiry, G.M. 19 February 2024. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 11 December 2024