Korotnovella jeppesenii Van Wichelen & Vanormelingen, 2016

Van Wichelen, Jeroen, D’Hondt, Sofie, Claeys, Myriam, Vyverman, Wim, Berney, Cédric, Bass, David & Vanormelingen, Pieter, 2016, A Hotspot of Amoebae Diversity: 8 New Naked Amoebae Associated with the Planktonic Bloom-forming Cyanobacterium Microcystis, Acta Protozoologica 55 (2), pp. 61-87 : 81-82

Korotnovella jeppesenii Van Wichelen & Vanormelingen sp. n.

Diagnosis: Locomotive form dactylopodial with a length of 16–41 µm and a width of 6–20 µm. Vesicu- lar nucleus about 2–3 µm in diameter with one slightly eccentrically located nucleolus. Floating form radial, maximally 16 µm long, containing up to 10 long, point- ed pseudopodia. Scales elliptical, disk-shaped with a length of 193–327 nm, a width of 124–203 nm, carrying a central spine of 47–97 nm in length. Amoebae occasionally form aggregates during cultivation. Cysts never observed.

Feeding behavior: Presumably highly specific grazer of Microcystis , similar to K. pelagolacustris .

Type material: Strain A 4 DVDPB is designated as the type strain. It is available from the NIES Microbial Culture Collection (NIES-3725). The 18S rDNA GenBank accession number is KP719186. Other strains: A1 JEPDK .

Type locality: Strain A4 DVDPB was isolated from a Microcystis bloom sample from a fish pond (Drie Vijvers) in De Panne ( Belgium) ( Table 1). Strain A1 JEPDK was isolated from a Microcystis bloom sample originating from a mesocosm in Silkeborg ( Denmark).

Etymology: Since this amoeba was first isolated from a mesocosm, being part of a long-term experiment estimating climate change effects on planktonic commu- nities under supervision of Dr. Erik Jeppesen ( Ozen et al. 2013), we named this amoeba in his honor. By doing so we also like to express our gratitude for his pioneering and stimulating research on shallow lake ecology.

Differential diagnosis: K. jeppesenii closely resembles K. diskophora (Smirnov 1999) in its general morphology and size. However the length of the scales is smaller (mean 277) than in K. diskophora (about 350). Its globular floating form with radiating pseudopodia also differs from K. diskophora ’s atypical irregular one. Moreover, K. jeppesenii occurs in Microcystis blooms where it specifically feeds on Microcystis cells whereas K. diskophora is a bacterivorous bottom-dweller (Smirnov 1999). K. pelagolacustris is larger in size (max. 65 µm), has larger scales (max. 391 nm) with larger spines (max. 163 nm) and differs in 18S rDNA sequence.