Phacelocarpus Endlicher & Diesing, 1845, nom. cons.

Holotype species: Phacelocarpus tortuosus Endlicher & Diesing

Original publication and holotype designation: Endlicher, S.L. & Diesing, C.M. (1845). Algarum natalensium diagnoses. Botanische Zeitung 3: 288-290.

Description: Plants of the largest species reach 50 cm in length and all have a firm, cartilaginous texture. Thalli are erect from crustose bases, flattened or terete, and are serrulate with radial or distichous acute teeth. Central axial filaments are prominent, each cell giving rise to generally 4 periaxial cells and associated cortical fascicles. The medulla contains the central axis plus numerous rhizoids, and intercalary refractive cells are present in the cortices of many species. Cystocarps have thick pericarps with transverse slits or grooves as ostioles. Plants are usually dioecious. The family PHACELOCARPACEAE is monogeneric family of 9 mostly Southern Hemisphere species. Plants are uniaxial. Secondary pit connections are abundant between cells of the pseudoparenchymatous inner cortex. Female reproduction is procarpic and polycarpogonial, the carpogonial branches being 2-celled and occurring in fertile clusters on determinate branch systems. Each cluster usually includes 1 or, more often, 2 carpogonial branches plus some sterile filaments, one of which includes an enlarged intercalary cell that is presumably the generative auxiliary cell. Fertilization probably leads to a connecting filament and a procarpic diploidization, although this is not definitely confirmed. The carposporophyte consists of a large basal fusion cell and outwardly radiating gonimoblast filaments that terminate in single or 2-celled chains of carposporangia. Cystocarps are protuberant and either sessile or stalked, the carposporophyte enclosed in a thick, ostiolate pericarp. Spermatangia are formed in pits aggregated into nemathecial short shoots or in tufts of filaments associated with the procarps. Tetrasporophytes are isomorphic with gametophytes, the tetrasporangia being zonately divided and either in the subsurface layers or lining cavities of nemathecial short shoots.

Information contributed by: G.T. Kraft. The most recent alteration to this page was made on 2015-10-19 by M.D. Guiry.

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

Gender: This genus name is currently treated as masculine.

Most recent taxonomic treatment adopted: Schneider, C.W. & Wynne, M.J. (2007). A synoptic review of the classification of red algal genera a half a century after Kylin's "Die Gattungen der Rhodophyceen". Botanica Marina 50: 197-249.

Comments: Distribution: The type and a second species, P. oligacanthus Kützing, are from South Africa. Phacelocarpus tristichus J. Agardh occurs in Mauritius, Madagascar and east Africa, whereas P. japonicus is endemic to southern Japan. The latter is the only Northern Hemisphere representative. The remaining species are restricted to Australasia, where they occur subtidally on open coasts and are a prominent component of the drift year round.

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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=35061

Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 19 October 2015. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 27 November 2024