Thienemanniella xena (Roback)

Namayandeh, Armin, Bilyj, Bohdan, Beresford, David V., Somers, Keith M. & Dillon, Peter J., 2012, 3324, Zootaxa 3324, pp. 1-65 : 49

Thienemanniella xena (Roback)

Figs 41A–D

Diagnosis. Small size <4 mm; head coloration similar to T. boltoni above; antenna ( Fig. 41A) 5-segmented, 0.8 as long as head length, basal segment pale brown gradually becoming darker distally, segment 2 dark brown, segments 3–5 pale; AR 1.3; mandible ( Fig. 41B) with 3 inner teeth plus an indication of a “proximal” tooth; mentum ( Fig. 41C) with three median teeth, central one well developed equal in size to the outer median teeth, 5 lateral teeth first two of equal size; VM plate narrow with angular basal extension; anal tubules cylindrical, 0.8 as long as posterior parapod; subbasal seta short, simple with bulbous base ( Fig. 41D).

Notes. A common and widely distributed species in the east. Easily identified by the combination of dark brown antennal segment 2, the mentum with three subequal median teeth, and the well developed first lateral tooth.

Ecology and habitat. Occurs in headwater intermittent and spring fed streams, similar to the preceding species.

Sampling sites. Massasauga, Arrowhead and Algonquin Provincial Parks.

Nearctic distribution. Canada: Alberta, Manitoba, Ontario. USA: Alaska, Florida, Georgia, Illinois Michigan, New York, Ohio, Pennsylvania, North Carolina, South Carolina, South Dakota .