Sabatieria flecha, Pastor, Catalina T. & Ward, De, 2003

Pastor, Catalina T. & Ward, De, 2003, Two new species of Sabatieria (Nematoda, Comesomatidae) from Golfo Nuevo, Chubut (Argentina), Zootaxa 172, pp. 1-12 : 5-7

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 presents a central cuticularized internal projection, 12 µm long.

Gubernaculum formed by one central tubular piece and two straight, dorso­caudally oriented 25 µm (0.8 abd) apophyses. Glandular tissue observed situated between spicula and gubernaculum. Pair of short pre­cloacal setae at 5 µm from the cloaca and 12 (7­12) pre­cloacal supplements as tiny and weakly cuticularised pits or alveoli with thin nerve endings are present. Tail 128 µm long (4.0 abd), approximately 1/3 cylindrical in shape. There are three caudal glands.

Females: Females are similar to males in general body shape, anterior sensilla, amphids and cuticle. Ovaries opposed, outstretched, anterior left and posterior to the right of the intestine. Tail 130 µm (3.7 abd).

Discussion. Sabatieria flecha sp. n. is characterized by the number of pre­cloacal supplements, short body length, value of b and the particular shape of the distal end of the spicule. Sabatieria flecha sp. n. resembles S. alata, Warwick 1973; in spicular tip shape, head shape and measurements. Sabatieria flecha sp. n. resembles S. alata Warwick, 1973 and S. heipi Chen & Vincx, 2000 in general spicular form, head shape and measurements. Sabatieria flecha sp. n. can be distinguished from both these species and from all other Sabatieria species included by Platt (1985) in the S. praedatrix ­ group by the particular shape of the dorsal distal end of the spicules. In S. flecha sp. n., the distal end has a prominent arrow­like projection in ventral position, not a triangular ventral enlargement as in S. alata or in S. heipi . Unfortunately no photos of these two species were available for comparison. Sabatieria flecha sp. n can also be distinguished from S. alata by smaller spicule and gubernaculum length (82­90 µm and 30­36 µm respectively in S. alat a); body length = 3070­3320 mm and = 1780­2990 mm in S. alata); values of a and b a=37­53, b=10; a=36­43, b= 9 in S. alata) and in tail shape, one half filiform in S. alata. Sabatieria flecha sp. n can also be distinguished from S. heipi by the number of turns in the amphids (4.2 turns in S. heipi ; spicule length (76 µm in S. heipi ); value of b = 6.5 in S. heipi ).

PLATE 1: Sabatieria flecha sp. n. A. Amphid on head of male; B. Buccal cavity of male; C. Tip of spicules with dorso­caudal projection; D. Entire male; E. Entire female; F. Lateral punctuations on male tail; G. Tip of male tail; H. Pre­cloacal supplements of male; I. Copulatory apparatus, glandular tissue between the spicules; J. Lateral punctuations on the male head; K. Copulatory apparatus, internal projection.

Figures

FIGURE 1: Map of the San José and San Matías Gulfs showing the sampling stations.

FIGURE 2: Sabatieria flecha sp. n. A. Head of male holotype; B. Head of female allotype; C. Anterior end of female; D. Tail of female allotype; E. Anterior end of male; F. copulatory apparatus male paratype, distal end of spicules; G. Posterior end of male holotype, copulatory apparatus, precloacal setae, supplements and tail. Scales: 1 = A, B; 2 = C, D, E; 3 = F, G.

Tables

TABLE 2. Measurements (µm) of Sabatieria flecha sp. n. (*: range, mean value in parentheses).

	HOLOTYPE Male	PARATYPE Males n=10 (*)	ALLOTYPE Female	PARATYPE Females n=10	JUVENILES n=3
L danr Daph	1260 110 162	1230­1510 (1391) 85­145 (118) 155­218 (193)	1400 126 205	1340­1740 (1483) 100­140 (120) 195­235 (211)	970­1030 (1006) 85­90 (87) 170­185 (177)
dav V% Daa Bdc	­­­­ ­­­­ 1132 10	­­­­­­­­­­­ ­­­­­­­­­­­ 1124­1390 (1267) 9­14 (12)	680 49 1270 10	650­900 (739) 47­59 1210­1580 (1342) 9­13 (10)	­­­­­­­­­­ ­­­­­­­­­­ 865­930 (896) 8­11 (10)
Bdnr	35	32­49 (39)	41	38­48 (42)	25­32 (29)
Bdph Mbd abd	35 35 36	35­55 (44) 35­55 (45) 33­45 (39)	53 55 35	42­55 (49) 50­66 (55) 30­42 (37)	26­45 (35) 29­55 (40) 22­35 (30)
HD	29	20­35 (27)	19	18­26 (21)	18­42 (30)
A%	64	56­76 (68)	64	53­64 (57)	18­42 (30)
R3	40	29­44 (35)	45	31­55 (45)	27­44 (34)
Spic Spic % gub	55 1.5 25	50­63 (58) 1.2­1.9 (1.5) 13­30 (22)	­­ ­­ ­­	­­­­­­­­­­­ ­­­­­­­­­­­ ­­­­­­­­­­­­	­­­­­­­­­­­ ­­­­­­­­­­­ ­­­­­­­­­­­­
gub%	0.8	0.3­0.9 (0.6)	­­	­­­­­­­­­­­­	­­­­­­­­­­­
PS	8	7­12 (8)	­­	­­­­­­­­­­­­	­­­­­­­­­­­
T a b	4.0 36 7.8	2.4­4.0 (3.3) 27­36 (31) 6.1­9.2 (7.3)	3.7 25 6.8	3.3­4.7 (3.8) 20­35 (27) 6.2­8.7 (7.0)	3.7­4.8 (4.1) 19­33 (27) 5.5­6.1 (5.7)
c	9.8	9.7­12.9 (11.3)	10.8	9.7­11.3 (10.5)	29.2­44.1 (37.6)