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 emarginata (Allman, 1844) Fig. 5 Material examined. A few floatoblasts from Sventupė pond were collected in July 2016. Description. Floatoblasts elongated in shape, with a circular ventral fenestra and small dorsal fenestra, covered by tubercles. Floatoblasts were 357-489 (407 +/- 18) µm long and 197-235 (216 +/- 6) µm (n=6) wide, L/W ratio 1.9; DfL 97-125 (107 +/- 9) µm ; DfW 60-82 (68 +/- 7) µm (n=3); VfL 101-184 (149 +/- 9) µm and VfW 110-162 (133 +/- 4) µm (n=6). The approximate size of statoblasts provided by Pajiedaite (1933) was 560 µm long and 260 µm wide. Figure 5. Plumatella emarginata floatoblast valves. The dorsal valve (left) has a characteristically small central fenestra; in the ventral valve (right) the fenestra is nearly circular. Scale bar: 100 µm . Distribution in Europe. Geimer and Massard (1986) defined the range of this species to include most of Europe. Okland and Okland (2005) considered P. emarginata to be a southern species, with limited distribution in Norway and Sweden. Remarks on habitat and ecology in Lithuania. Pajiedaitė (1933) described morphology of P. emarginata colonies, but her text is not clear about the location of collection sites. However, the statoblasts she found were recorded from Pastys Lake ( 55°42'36"N , 25°41'48"E ), Satarecius pond and Dubysa River (Kaunas district, 55°12'12"N , 23°30'28"E ). In our survey only a few statoblasts were found in Sventupės pond (Table 1). Wood and Okamura (2005) noted that P. emarginata is particularly tolerant of rapidly-flowing water. The occurrence of floatoblasts in the Neries River (Kaunas district - not included in this study) is consistent with this observation, although colonies were not found. From our data P. emarginata would be considered uncommon in Lithuania, although this should be verified through further surveys. Remarks. The species is widely distributed throughout the Holarctic ( Wood and Okamura 2005 ), although some reports may have confused it with similar species, P. mukaii or P. reticulata ( Massard and Geimer 2008a ).