Family: Chaetocerotaceae Ralfs in Pritchard
Genus: Chaetoceros Ehrenberg
Scientific name: Chaetoceros lauderi Ralfs
Chaetoceros weissflogii Schütt
Pavillard, 1925: p. 45, Fig. 71; Hustedt, 1930: p.683, Fig. 387; Allen and Cupp, 1935: p. 137, Fig.59; Cupp, 1943: p. 118, Fig. 73; Crosby and Wood, 1958: p. 517, Pl. 37: 51; Hendey, 1964: p. 125, Pl. XIII: 3; Ricard, 1987: p. 203, Fig. 455.
Cells rectangular, united to form straight or twisted chains; cells deep, with shallow valve mantle and wide girdle; valve surface almost flat; straight setae emerge from the corners of the valves at right angles to the chain axis. Foramina narrow, linear to linear-elliptic; diameter of valve 22-50 µm (Hendey, 1964).
Apical axis 19-22 µm; pervalvar axis 18-20 µm.
Neritic, south temperate form.
Sites of occurrence in RSA:
In Winter 2006 Cruise, this species occurred at few sites (refer sites map), usually in small numbers; however, it was quite abundant at some localities; maximum abundance (7.8*10^3 cells/l) was associated with Kuwaiti waters in the northwestern part of the inner RSA (Stations 1 and 14).