Amphidinium klebsii

Super Group: 
Kofoid & Swezy 1921


The body is subeyliudrieal, rounded posteriorly, subtruncate anteriorly with the middle portion drawn out in a slender tongue deflected to the left. The length of the body is 1.72 transdiameters at the widest part. The tongue-shaped portion at the anterior end is the epicone, which is separated from the rest of the body by the wide girdle. The exact limits of the girdle and epicone are not shown in Klebs 's figures (1884). Its length above the of the girdle is about 0.2 of the total length of the body, its width about 0.35 transdiameter. The hypocone is cylindrical with its sides subparallel for the middle third of their extent, rounded above and below. The antapex is broad and slightly rounded, while anteriorly the sides of the hypocone below the girdle swell forward and outward, forming wide, high shoulders, the left one narrower than the right. The girdle is a wide circle embracing the narrow, neeklike portion at the anterior end of the body. Its width is about 0.25 transdiameter. Its proximal border, as well as the sulcus, and the connections of girdle and sulcus are not indicated in Klebs 's figures (1884). The longitudinal flagellum arises a short distance below the probable point of union of girdle and sulcus. The transverse flagellum arises in his figure on the right dorsal side of the body, a condition unparalleled in the dinoflagellates and one which is probably an error of drawing or interpretation. The nucleus is a large, spherical body occupying the posterior half of the hypocone. Its axis is 0.43 transdiameter in length. The cytoplasm is filled with spherules of varying size and long, tapering ehromatophores, which radiate forward and outward from the region of the nucleus in the posterior part of the body. The color of the organism is not noted by Klebs. The surfacen is apparently marked by a few longitudinal furrows or striae extending the length of the hypocone.

Type illustration / Type locality / Type specimen

The type species (holotype) of the genus Amphidinium is Amphidinium operculatum Claparède & Lachmann.

ASQME static network (beta)

ASQME dynamic network (beta)

ASQME map (beta)