Notosolenus lashue Lee and Patterson, 2000

Lee, Won Je & Patterson, David J., 2000, Heterotrophic flagellates (Protista) from marine sediments of Botany Bay, Australia, Journal of Natural History 34, pp. 483-562 : 510

Notosolenus lashue Lee and Patterson , n. sp.

(fi gures 9e, 11a -e. Type micrograph: fi gure 11b)

Diagnosis. Notosolenus , mostly 14-15 Mm long, with a longitudinal dorsal ridged groove to the left side, ventrally with a groove and one median ridge.

Description. Colourless fl attened euglenid, about 13-16 Mm long (mostly 14-15 Mm) and 8-10 Mm wide, the ratio of length to width is 1.4 to 2.1. Cell ovate or pear-shaped, anteriorly acute, posteriorly blunt or rounded. A distinct ventral groove running along the cell becomes broader towards the posterior. There is one fi ne median longitudinal ventral ridge which could easily be overlooked and which extends from the apex. A well-developed longitudinal dorsal groove runs along the left side of the cell. Two fl agella of unequal length emerge from the fl agellar canal. The anterior fl agellum is about 1.0-1.3 times the cell length, it beats slowly when the cell is stopped but during normal gliding motion, the fl agellum is extended and the front part is most active. The recurrent posterior fl agellum inserts into the cell at the anterior end of the ventral groove. It is about 0.5-1.0 times the length of the cell and usually lies in the ventral groove when the cell is gliding. The ovate reservoir is situated anteriorly near the right ventral face of the cell. A large long nucleus lies in the left side of the cell. This species contains numerous refractile granules. Glides with the anterior fl agellum directed anteriorly. Commonly observed.

Remarks. We assign this species to Notosolenus because it is a rigid colourless euglenid with a fl attened body, no visible mouth and two emergent fl agella. This species is the same length as N. esulcis Larsen, 1987, but it can be distinguished because N. esulcis has four shallow ridges on the dorsal face of the cell ( Larsen, 1987). Notosolenus lashue resembles N. canellatus (see Skuja, 1948) and N. pyriforme Lee and Patterson n. sp. in having a dorsal groove, but this species can be distinguished because N. canellatus and N. pyriforme have lateral fl anges and N. lashue has a well-marked ridge in the dorsal groove. The dorsal face of N. lashue i s similar to that of N. similis (see below) in having one longitudinal groove with a ridge, but N. lashue can be distinguished from N. similis because there is a ventral groove and ridge running along the entire cell. The ventral groove of N. lashue resembles that of N. scutulum (see Larsen and Patterson, 1990) in that the groove becomes gradually broader towards the posterior end of the cell, but the species can be distinguished by its round posterior end, the distinct ventral ridge and the central location of the dorsal groove.