| Description: |
Stillabothrium mariae n. sp. Ruhnke, Pommelle and Reyda (Informal synonym: Rhinebothriinae New genus 3 n. sp. 4 of Healy et al. (2009), Caira et al. (2014), Ruhnke et al. (2015), Marques and Caira (2016).) (Figs. 6–7) Description (based on whole mounts of 26 complete mature worms, cross sections from 2 scoleces and 2 strobilae, and 5 scoleces prepared for SEM): Worms (Fig. 6A) euapolytic, acraspedote, 1.43–2.74 mm (2.03 ± 1.43; n ¼ 26) long, greatest width 194–318 (255 ± 36; n ¼ 26) at level of scolex; 6–13 (9 ± 1.8; n ¼ 26) proglottids per worm. Cephalic peduncle absent; darkly staining germinative zone present. Scolex (Figs. 6B, 7A) consisting of scolex proper bearing four stalked bothridia. Stalks 103–175 (137 ± 19; n ¼ 14) long by 41– 130 (74 ± 25; n ¼ 14) wide, attached posterior to middle of bothridia. Bothridia varying in shape due to degree of contraction, from cup-like to nearly flat, facially loculated, 245–319 (283 ± 21; n ¼ 26) long by 108–223 (162 ±33; n ¼ 26) wide; bothridial margins with thin rim of tissue (Fig. 7A). Anterior region of bothridia (Figs. 6B, 7A) with 10–12 horizontally oriented loculi that are wider than long, posterior loculus of relative equal length and width. Anterior loculus 20–33 (27 ± 4; n ¼ 21) long by 27–48 (36 ± 5; n ¼ 21) wide. Posterior-most loculus of bothridium laced with horizontal and longitudinal muscle fibers (see Fig. 6B) and lacking conspicuous septa. Marginal loculi present posterior to horizontal loculi, 11 or 13 in number (n ¼ 6). Loculi and septa (Fig. 7B) of distal bothridial surfaces bearing capilliform filitriches and coniform spinitriches. Bothridial rim bearing capilliform filitriches (Fig. 7C). Proximal bothridial surfaces away from rim (Fig. 7C) bearing acicular filitriches. Posterior portion of proximal bothridial surface (Figs. 7D, 7E) bearing patch of coniform spinitriches near, but not extending to, bothridial rim. Isolated cilia observed on distal bothridial surfaces (Fig. 7B). Strobila bearing capilliform filitriches only. Strobila (Fig. 6A) with ... |