Cordylecladia J.Agardh, 1852
Lectotype species: Cordylecladia erecta (Greville) J.Agardh
Original publication: Agardh, J.G. (1852). Species genera et ordines algarum, seu descriptiones succinctae specierum, generum et ordinum, quibus algarum regnum constituitur. Volumis secundi: Algas florideas complectens. Part 2, fasc. 2. pp. 577-700 [701-720, Addenda and Index]. Lundae [Lund]: C.W.K. Gleerup.
Request PDFType designated in: Schmitz, F. (1889). Systematische Übersicht der bisher bekannten Gattungen der Florideen. Flora oder Allgemeine botanische Zeitung 72: 435-456, pl. XXI.
Description: Thallus with a flattened rhizomatous holdfast coalescing to form an extensive crustose base and erect narrowly forked, irregularly and sparsely branched terete or slightly compressed erect fronds, firm and cartilaginous; construction multiaxial, cortex of 2-3 layers of small cells, medulla of larger, relatively colourless, pseudoparencymatous, axially elongated cells. Gametangial plants dioecious; spermatangia in superficial sori in swollen apices, formed in pairs from elongated initials modified from cortical cells; procarpic, carpogonial branches in cortex, 4-celled, formed singly or occasionally in pairs on a large, mulinucleate supporting cell with a 2- or 3-celled auxiliary cell branch, gonimoblast developing outwards from a fusion cell, most cells being transformed to carposporangia in 2-3 lobes of different ages; cystocarps ostiolate, formed in clusters in swollen areas at the apices, never coronate, strongly protruding outwards, tela arachnoidea absent. Tetrasporangia formed in an intercalary position from cortical cells, in sori confined to swollen areas near apices, spores regularly cruciately arranged.
Information contributed by: M.D. Guiry. The most recent alteration to this page was made on 2017-01-24 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 feminine.
Most recent taxonomic treatment adopted: Brodie, J. & Guiry, M.D. (1988). Life history and reproduction of Cordylecladia erecta (Rhodymeniaceae, Rhodophyta). British Phycological Journal 23: 347-364.
Comments: Cordylecladia erecta was for many years considered to be a species of Gracilaria, particularly in the British Isles (Jones 1962). However, the structure and reproduction of C. erecta from France was described in detail by G. Feldmann (1967) who showed clearly that the original placement, by J. Agardh (1852), of Cordylecladia in the Rhodymeniaceae was correct. Brodie and Guiry (1988) found that Cordylecladia erecta from Ireland has a ‘Polysiphonia-type’ life history in culture. Reproduction in all phases is under photoperiodic control at 10 and 15%C. Night-breaks of 1 h in a 16-h night (considered, incorrectly, by many as the acid test of a photoperiodic response) does not, however, inhibit reproduction. The response to daylength is photoperiodic, nevertheless, as equivalent photon dosages given at 8-, 10- and 12-h daylengths resulted in reproduction, whereas those given at 14- and 16-h daylengths did not. In the British Isles and northern France, C. erecta reproduces largely in winter and spring, which agrees well with culture date. The structure and reproduction of Cordylecladia erecta and C. guiryi Gargiulo, Furnari et Cormaci (1991) are very similar to that of Rhodymenia (q.v.), but Cordylecladia is distinguishable on the basis of its terete and narrowly forked fronds, and the formation of reproductive structures in apical, swollen, spindle-like structures shed after reproduction. Cordylecladia erecta is a north-eastern Atlantic endemic found from the Shetland Is. south to the north coast of Spain (Cullinane 1978; Irvine and Guiry 1983; Brodie and Guiry 1988). Plants are commonest in western Ireland, south-western Britain and northern and north-western France where they occur in the lower intertidal on sand- or silt-covered rocks and in the subtidal to a depth of 32 m. Plants are capable of surviving burial by sand for extended periods. C. guiryi is known only from the subtidal of Sicily where it grows epiphytically on the leaves of sea-grasses and is distinguished from C. erecta by its smaller size, a 3-celled auxiliary cell branch, and the formation of erect fronds singly from a rhizomatous base. Cordylecladia furcellata J. Agardh from south-eastern Australia has recently been referred to the new genus Cephalocystis (q.v.), which resembles Cordylecladia in external appearance. Small-subunit rRNA gene sequences (Millar and others 1996) indicate that C. erecta is, as suggested by Brodie and Guiry (1988), very closely related to species of Rhodymenia.
Verification of Data
Users are responsible for verifying the accuracy of information before use, as noted on the website Content page.
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=37302
Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 24 January 2017. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 22 November 2024
