Luticola centraloporea M.Rybak, Getler et Kociolek, 2024

Luticola centraloporea M.Rybak, Getler et Kociolek sp. nov.

LM observations (1A–T):— Valves elliptic-lanceolate to linear-lanceolate with rounded apices ( Figs 1A–T View FIGURE 1 ). Valve length 9.0–21.0 µm, width 4.0–6.0 µm and 20–24 striae in 10 µm (n = 35). Axial area narrow and linear. Central area rectangular to bow-tie shaped and bordered near margin by 2–3 shortened striae ( Figs 1A–H View FIGURE 1 ). Isolated pore clearly visible in the central part of central area almost between proximal raphe endings ( Figs 1A–H View FIGURE 1 ). Raphe filiform, with proximal raphe endings clearly curved away from the isolated pore, distal raphe endings barely visible (Figs C, D) elongated, weakly hooked opposite the proximal raphe endings. Striae clearly radiate with 3–4 areolae per striae. No morphological differences were observed between the European and North American populations.

SEM observations (2A–H, 3A–H):— Externally, striae composed by 3–4 areolae per striae, rounded, sometimes enlarged near the valve face margin ( Figs 2A–D View FIGURE 2 , 3A, B View FIGURE 3 ). Internally, areolae covered by hymen forming continuous strip, separated by not thickened virgae ( Figs 3C View FIGURE 3 ). Single row of areolae (interrupted on the apices) present also on valve mantle ( Figs 2C, D, G View FIGURE 2 , 3A, B, G View FIGURE 3 ). Both, valve face and mantle areolae circular in shape. Isolated pore rounded, located in the central part of the central area, almost between proximal raphe endings ( Figs 2A–F View FIGURE 2 , 3A, B, E View FIGURE 3 ). Raphe branches straight and filiform, with proximal endings pore-like shaped and curved away of isolated pore bearing side ( Figs 2A–F View FIGURE 2 , 3A, B, E View FIGURE 3 ). Distal raphe endings pore-like shaped, terminating onto valve face, only slightly bent away of isolate pore bearing side ( Figs 2A–D, G View FIGURE 2 , 3A, B, G View FIGURE 3 ). Internally, isolated pore opening small, c-shaped, positioned midway between valve margin and the central area ( Fig. 3F View FIGURE 3 ). Longitudinal channels located along on both sides of valves ( Fig 3C View FIGURE 3 ). Externally, central area bow-tie shaped with a smooth surface ( Figs 2c View FIGURE 2 , 3A, B View FIGURE 3 ). Girdle bands with two rows of poroids ( Fig 3D View FIGURE 3 ). No morphological differences were observed between the European and North American populations.

Type:— United States of America, Castle Rock Lake, Wisconsin, 43°59’56”N 89°59’33”W, moss sample from lake shore, collected in April 2015. Holotype: Slide no. SZCZ 29315 View Materials at the University of Szczecin , isotype 1 slide no. 2015/12 and unmounted material with the same number at the University of Rzeszów , Poland, isotype 2 slide no. WA0000166879 and unmounted material with the same number at the Herbarium of the Faculty of Biology , University of Warsaw. The holotype population is presented in Figs 1L–T View FIGURE 1 . GoogleMaps

Etymology:— Name refers to the position of isolated pore.

Distribution:— Probably widely distributed in the northern hemisphere, observed in Wisconsin ( USA) and in Warsaw ( Poland).

Ecology and accompanying taxa:— In both analyzed samples the species occurred very rarely (<0.5% share in the community) also in both samples, diatoms were rare and represented only a few species. In sample 2015/12, the most common associated species were Geissleria decussis (Østrup) Lange-Bertalot & Metzeltin (1996: 65) , Planothidium sp. , Skabitschewskia peragalloi (Brun & Héribaud) Kuliskovskiy & Lange-Bertalot (in Kulikovskiy et al. 2015: 85). In sample 2022/199 the most common taxa encountered were Humidophila delognei Goeyers & Van de Vijver (2023: 3) and Luticola micra Levkov, Metzeltin & A.Pavlov (2013: 156) .

Similar species:— Luticola confusa M.Rybak & Czarnota (in Rybak et al. 2023: 8), L. imbricatiformis Levkov, Metzeltin & Pavlov (2013: 134) , L. mitis Levkov, Metzeltin & A.Pavlov (2013: 161) , L. mutica , L. rotunda Solak & Levkov (in Levkov et al. 2013: 212).