Catenula evelinae (Marcus, 1945) Larsson, Ahmadzadeh & Jondelius, 2008

Figures 2, 3

General morphology. The body, with length varying between 0.6 and 0.8 mm, is elongate with truncated ante- rior tip and rounded posterior tip. The anterior region has long-ciliated sensorial cells and a statocyst with a statolith in the prostomium base (Figs 2, 3). In addition, there is a pre-oral swelling with ciliated furrows and occurrence of conspicuous epidermal inclusions. The intestine is located in the posterior 2/3 of the body. A protonephridium duct is visible in the posterior 1/6 of the body and the nephridiopore is subterminal (Fig. 3).

Specimens examined. MZU 00203: coll. J.A.L. Braccini and F. Brusa, 26 March 2012, Brazil, Rio Grande do Sul, Tramandaí (30°05ʹ09ʺ S, 050°10ʹ24ʺ W) ; coll. J.A.L. Braccini and F. Brusa, 26 March 2012, Brazil, Rio Grande do Sul, Capivari do Sul (30°10ʹ22ʺ S, 050°23ʹ10ʺ W).

Remarks on ecology and distribution. Species with low abundance in each wetland in the summer/autumn survey and absent from the winter/spring survey (Table 2). Catenula evelinae was previously reported only for its type locality, in the city of São Paulo, in southeast Brazil (Marcus 1945a). Thus, the present record represents a southeastern range extension of about 800 km.

the Coastal Plain during 2 surveys done in 2012.

tips; pre-oral region longer than wide. There is a statocyst located approximately in the middle of the cephalic lobe; a ciliated pit is absent. The intestine is large, 2/3 of the body length (Figs 4, 5).

Specimens examined. MZU 00204: coll. J.A.L. Braccini and F. Brusa, 12 March 2012, Brazil, Rio Grande do Sul, Osório ( Wetland 3) (29°52ʹ02ʺ S, 050°05ʹ24ʺ W).

Remarks on ecology and distribution: Species with moderate abundance in the summer/autumn survey, but absent in the winter/spring survey (Table 2). Similarly to C. evelinae, C. leuca was previously recorded only in its type locality, in the city of São Paulo (Marcus 1945a). The present record, thereby, increases its known distribution about 800 km to the southeast.

Catenula turgida (Zacharias, 1902) Larsson, Ahmadzadeh & Jondelius, 2008

Figures 6, 7

General morphology. Body length (0.4–0.6 mm) similar to those from the Holarctic region; mean length a little shorter than that of São Paulo specimens (0.6–0.8 mm). Their main morphological characteristics are: absence of statocysts, body length 5 or 6 times longer than wide, preoral ring with 4 longitudinal grooves on each side (Figs 6, 7) and 3–4 µm long rhabdoids.

Specimens examined. MZU 00205: coll. J.A.L. Braccini and F. Brusa, 12 March 2012, Brazil, Rio Grande do Sul, Tramandaí (30°05ʹ09ʺ S, 050°10ʹ24ʺ W).

Remarks on ecology and distribution. This species had low abundance in both surveys (Table 2). It was described from the Holarctic region (Zacharias 1902, Larsson and Willems 2010) and previously reported for the Neotropical region in the city of São Paulo, in southeast Brazil (Marcus 1945a, b). The present record represents an extension of its known distribution about 800 km to the southeast.