La familia Hemiaulaceae (Bacillariophyceae) de las aguas marinas chilenas

Abstract

The Family Hemiaulaceae comprises four genera, all of which have been previously reported for coastal waters off Chile, and represented by the following taxa: Cerataulina pelagica (Cleve) Hendey, Hemiaulus sinensis Greville, H. membranaceus Cleve, Climacodium biconcavum Cleve, Eucampia antarctica (Castracane) Mangin, E. cornuta (Cleve) Grunow and E. zodiacus Ehrenberg. However, examination with light and electron microscopy of marine samples from along the Chilean coast and the Antarctic Peninsula (including those used in earlier publications) revealed that (1) the genus Cerataulina is represented by C. pelagica, and is distributed along the Chilean coast between Arica in the north and the Magellan Strait in the south, (2) the genus Eucampia comprises four taxa: E. zodiacus f. cylindrocornis Syvertsen (previously reported for Chile as E. zodiacus f. zodiacus), E. zodiacus f. recta Rivera, Avaria & Cruces (described here), E. cornuta and E. antarctica. The former three taxa occur in the central and northern coast of Chile, while E. antarctica lives in Antarctic waters south of the Magellan Strait, (3) earlier records of Hemialus membranaceus, H. sinensis and Climacodium biconcavum in Chilean waters are misidentifications of Eucampia zodiacus f. recta f. nov. A short description is included for each taxon, and photographs provide information about the main morphological characteristics.