Sabatieria flecha sp. n. (Figure 2 A­G; Plate 1 A­K; Table 2) Type material : Ten males and ten females and three juveniles on slide numbers: 1 HOLO­ TYPE, MACN N1 34615; 1 ALLOTYPE, MACN N1 34616; PARATYPES, MACN N1 34617­34628. Col.: Lic. H. Zaixso. Type locality: San José Gulf and San Matías Gulf, Chubut province, Argentina. STA­ TION S: S19 : (adult no. 7,9,10); (4,5,6,7); juv.(1); S35 : (10); juv.(3); S50 : (4; 2,3); S105 : (9); S106 : (1,2,3, 5, 6); (1, 8); juv.(2); S108 : (8). Habitat : Sabatieria flecha sp. n. was found in very fine sand (median particle size 60­ 8 µm), 56­95 m depth, from San José Gulf and south coast of San Matías Gulf (Fig. 1). Etymolog y: From the Spanish word " flecha ", in reference to the arrow shape spicular tip. Measurement s: see Table 2. Description.Males: Body cylindrical, tapers slightly towards the anterior end and has a conical tail terminus. Cuticle, annulated and punctuated. Punctuations arranged in transverse rows with lateral differentiations, having larger dots irregularly arranged on the lateral fields. Six inner small labial papillae, 6 outer labial setae 1­1.5 µm long and 4 cephalic setae 4­4.5 µm long. Cervical region with 2­3 somatic setae posterior to the amphid. Buccal cavity small, cup shaped, the pharyngeal muscles surround the posterior part of the stoma. Amphids spiralled ventrally towards the center with two and a half turns (9 µm diam., 64% bda), located 7­8 µm from anterior end. Pharynx, cylindrical (155­218 µm long), and enlarged posteriorly. Cardia is small. Ventral gland located at the cardia level and opens through an ampulla 80­135 µm from anterior end. Reproductive system is diorchic, with opposed and outstretched testes, in anterior left and posterior right position to the intestine. Spicules, curved 47 µm (1.5 abd) in chord length with a distal end having prominent curves in dorsal and ventral position and in dorsal view resembles an arrow shape. This particular shape does not change from different viewpoints. Spicules are bent, the proximal end ...