Epsilonema steineri Chitwood 1935

• Main Authors: Fedyaeva, Maria A., Neretina, Tatjana V., Konovalova, Olga P., Tchesunov, Alexei V.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2016
• Subjects: Biodiversity; Taxonomy; Animalia; Nematoda; Adenophorea; Desmodorida; Epsilonematidae; Epsilonema; Epsilonema steineri; karelia*; karelian; White Sea
• Online Access: https://doi.org/10.5281/zenodo.5628358; http://treatment.plazi.org/id/03F17E4CFF9EFFD6FF30FE6DFAE35D9D

Epsilonema steineri Chitwood, 1935 Figs 7–10, Table 4 (morphometrics). Material. Ten males and ten females. Locality. White Sea (Northern Russia), Karelian Coast of the Kandalaksha Bay, vicinity of the White Sea Biological Station (66°33'N, 33°06'E), Velikaja Salma Strait between the Veliky Island and Kindo Peninsula, depth 5 m, red algae. 18–27 August 2013. Description. Body ϵ-shaped and narrowest in the region of the ventral bend between pharynx and anterior gonad. Male body widest in pharyngeal region. Female body widest in region of reproductive system. Head rostrum (cephalic capsule) small, conoid, formed by smooth, uniformly thick cuticle (Fig. 10 A, B). Somatic cuticle posterior to rostrum distinctly annulated. Annules decrease in width to mid-body and then increase again: there three annules in 10 µm on anterior body just posterior to rostrum, seven annules in 10 µm on the region of ventral bend, and four annules in 10 µm on posterior half of the body. Cuticle of a male composed of 157 annules. Annules of the pharyngeal region ornamented with one row of tiny oval vacuoles. Very tiny spines, visible distinctly only with SEM, located on the dorsal side of the body and directed backwards (Fig. 10 E). Spines located predominantly on the anterior body, from body bend to anal region; spines on dorsal side of posterior half of the body 2–2.5 times longer than those on ventral side (3 Μ m and 1 Μ m, respectively). Labial region composed of six lips usually inverted into the head in fixed specimens (Fig. 10 A). Six inner labial papillae located on outer side of the lips. Six outer labial as short setae on anterior part of the rostrum. Four cephalic setae (3.6–8.0 Μ m long in males, 3.7–8.3 Μ m long in females) situated at level of the amphideal fovea. Amphideal foveas spirally coiled in 1.5 turns (Fig. 10 B); their width 0.4–1.7 Μ m in males and 0.8–1.4 Μ m in females; the amphideal foveas shifted a bit to dorso-lateral position. No evident difference between foveas of males and females. Thirty to 50 thin ...