Open AccessBenthic diatoms associated to living thrombolites.
Author(s) -
Siqueiros Beltrones,
David Alfaro
Publication year - 2006
Publication title -
cicimar oceánides
Language(s) - English
Resource type - Journals
eISSN - 2448-9123
pISSN - 1870-0713
DOI - 10.37543/oceanides.v21i1-2.30
Subject(s) - benthic zone , nitzschia , navicula , biology , mangrove , taxon , ecology , diatom , botany , phytoplankton , nutrient
The first floristic account of benthic diatoms associated to recent (living) thrombolites or protrombolites was determined. These sedimentary formations generated by cyanophytes that exhibit particular conditions of stability were discovered in beaches of Ensenada de La Paz. These represent new substrata for the growth of marine benthic diatoms. Fragments of pro-thrombolites collected monthly from August to November in four sites of the Ensenada were examined. The pro-thrombolite cover consisted of a cyanophyte complex where Microcoleus chthonoplastes, Oscillatoria limosa/Lyngbia aestuarii and other filamentous forms are the main components. A total of 150 diatom taxa were identified, mainly pennateforms. The presence of certain taxa shows the influence of nearby mangroves and hypersaline environments. Although the species composition does not seem to differ from other assemblages in the region, dominant taxa are different. The most frequent taxa were: Mastogloia pumila (Grun.) Cleve, Mastogloia obliqua Hagelstein, Navicula formenterae Cleve, Nitzschia frustulum var. perminuta Grunow, Nitzschia scalpelliformis (Grun.) Grunow, Nitzschia sigma (Kütz.) W. Smith, Psammodyction constricta (Kütz.) Ralfs, Rhopalodia gibberula (Ehrenberg) O. Müller, Seminavis sp. 1. The species richness is highconsidering the stability and homogeneity of the pro-thrombolithic system.