Plumatella fungosa (Pallas, 1768)

Chae, Hyun Sook, Kil, Hyun Jong & Seo, Ho Jin Yang and Ji Eun, 2024, Freshwater bryozoans of Korea-observations on living colonies and three new records, Journal of Species Research 13 (1), pp. 50-60 : 55

* 7. Plumatella fungosa (Pallas, 1768) ( Fig. 6 ) Ṟǭḓẍūḓ끼ḇNj (ljḡ)

Tubularia fungosa Pallas, 1768: 565-572 .

Plumatella fungosa Massard and Geimer, 1991a: 246 , Pl. 1, fig. 2; 1991b: 152, figs. 3-6; Wood and Okamura, 2005: 57, 86-88, figs. 27, 28, 50, 51; Hirose and Mawatari, 2011b: 13, fig. 5B.

Material examined. Baekgok Stream , 22 September 2016 ; NIBRIV0000777398, NIBRIV0000777399, Sejong Weir , 8 June 2016 ; Sunpo Wetland , 18 August 2016 .

Substratum. Wood.

Description. Floatoblast oval to elliptical, laterally asymmetrical, 296-344 μm long by 211-266 μm wide, length/width ratio of about 1.3. Dorsal fenestra almost round, relatively small, 156-164 μm long by 123-152 μm wide ( Fig. 6A ). Ventral fenestra larger, oval, almost circular, often with a central prominence, 199-239 μm long by 164-201 μm wide ( Fig. 6B ). Surface of dorsal, ventral, and annulus uniformly tuberculate and reticulate ( Fig. 6C ). Ventral strongly convex and dorsal almost flat. Sessoblasts oval, completely covered with uniform tubercles, annulus narrow and smooth, 338.2 μm long by 263.15 μm wide, fenestra 311.51 μm long by 233.38 μm wide, annulus 12.54-16.31 μm ( Fig. 6D ).

Remarks. Plumatella fungosa was easily confused with both Pl. repens and Pl. rugosa before SEM was used for the observation of statoblast. Wood and Okamura (2005) provided with major morphological differences between the statoblasts of the three species for their identification. Also, the reticulation and tuberculation on the fenestra and annulus of the statoblast are different from those of Pl. repens and Pl. rugosa .

Distribution. Korea, Japan, and Europe.

Figures

Fig. 6. Plumatella fungosa(Pallas, 1768). A, Dorsal view, flatoblast; B, Ventral view, flatoblast; C, Annulus and fenestra in detail; D, Sess- oblast. Scale bars: A, B, D=100μm, C=30μm.