Freshwater bryozoans of Lithuania (Bryozoa) Author Satkauskienė, Ingrida Author Wood, Timothy Author Rutkauskaitė-Sucilienė, Jurgita Author Mildazienė, Vida Author Tuckutė, Simona text ZooKeys 2018 774 53 75 http://dx.doi.org/10.3897/zookeys.774.21769 journal article http://dx.doi.org/10.3897/zookeys.774.21769 1313-2970-774-53 3F266A726CB74867B13FFBDDDBFB6D0C Plumatella geimermassardi Wood & Okamura, 2004 Fig. 3 Material examined. A few floatoblasts from Lampėdziai Lake in April 2016. P. geimermassardi were recorded in Lithuania for the first time. However, the species is so far represented only by statoblasts. Description. Floatoblasts were identified by the large dorsal fenestra with tubercles and narrow annulus. The annulus at the poles is mostly as large as laterally and is covered by weakly visible tubercles (Fig. 3). Length and width of floatoblast were 311-325 (317 +/- 4) μm and 221-273 (244 +/- 15) μm (n=3) respectively. L/W ratio 1.3; DfL 199-205 (202 +/- 3) μm ; DfW 174-201 (187 +/- 13) μm (n=3); VfL 200-254 (227 +/- 26) μm and VfW 185-198 (192 +/- 6) μm (n=3). Figure 3. Plumatella geimermassardi . Scanning electron micrograph of the floatoblast ventral valve showing the uniformly narrow annulus. Scale bar: 100 μm . Distribution in Europe. Plumatella geimermassardi is known from England, Ireland, Belgium, southern Norway, northern Germany, Italy and Finland ( Wood and Okamura 2005 ). Remarks. Floatoblasts of P. geimermassardi are among the smallest floatoblasts among all European plumatellids with an average length of around 320 µm ( Wood and Okamura 2004 ). The uniformly narrow annulus offers an easy identifying feature characteristic for broad floatoblasts in this species. The relatively large area of dorsal and ventral fenestrae is matched only by those of P. nitens or Stephanella hina on other continents ( Wood 1996 ; Toriumi 1955 ).