Spirinia sophia, Silva, Maria Cristina Da, Castro, Francisco José Victor De, Cavalcanti, Mariana Da Fonseca & Fonsêca-Genevois, Verônica Da, 2009

Silva, Maria Cristina Da, Castro, Francisco José Victor De, Cavalcanti, Mariana Da Fonseca & Fonsêca-Genevois, Verônica Da, 2009, Spirinia lara sp. n. and Spirinia sophia sp. n. (Nematoda, Desmodoridae) from the Brazilian continental margin (Campos Basin, Rio de Janeiro), Zootaxa 2081, pp. 31-45 : 39-44

Species: Spirinia sophia sp. n.

Figs 5–7

Description. Holotype male: Campos Basin (Rio de Janeiro, Brazil): deep-sea, 750 meters depth with boxcorer, in silt-clay sediments, 0–2cm profile. National Museum of Rio de Janeiro, Brazil (MNRJ 324). Allotype female: same collection data as holotype. National Museum of Rio de Janeiro, Brazil (MNRJ 325).

Paratypes one male and one female: same collection data. Meiofauna Laboratory of the Zoology Department, Universidade Federal de Pernambuco (male 1089 NM LMZOO-UFPE, female 1098 NM LMZOO-UFPE).

Etymology. The species name is in honor of Sofia da Fonsêca-Genevois, daughter of the co-author, Dr. Verônica da Fonsêca-Genevois.

Measurements: Table 3 .

Adult male. Rounded head and conical tail. Cuticle with transverse striae, more widely spaced in head region (1 µm apart) than in tail (0.5 µm apart). Inner labial sensilla not observed. Six outer labial papillae and four cephalic setae in separate circles. Amphideal fovea a single ventral spiral, 8 µm in diameter (55% cbd), surrounded by transverse cuticular striation. Subcephalic setae present, equally long as cephalic setae. Cervical setae irregularly distributed around body, concentrated in neck region and scarce on rest of body. Somatic papillae several, irregularly distributed dorsally and ventrally on body, not associated with epidermal gland cells. Buccal cavity with one dorsal tooth and two minute ventrosublateral teeth. Secretory-excretory pore not observed. Pharynx with round to oval terminal bulb (diameter 67% cbd). One outstretched testis lying to the left of the intestine. Spicules strongly ventrally curved, with marked capitulum. Three ejaculatory glands dorsal to spicule. Gubernaculum without dorsal apophysis. Five papilliform precloacal supplements associated with glands cells, 16 µm apart, most posterior papillum 20 µm from cloaca. Two somatic setae at tail terminus. 16 postcloacal ventral papillae. Three caudal glands ending in a spinneret. Tail conical.

TABLE 4. Morphometric features (Μm) of Spirinia sophia (sp. n.) compared to similar species. Measurements Spirinia sophia sp. n. Spirinia gerlachi Luc & de Coninck (1959) Male

L 1945–2180 1494 a 108–112 37.5 b 17–21 11 c 23–24 10.4 Female

L 1365–1810 1492 V % 55–57 43% a 58 –77 24 b 14–17 14.2 c 12–22 11.5

Adult female. Largely similar to male in most morphometric features, but with sexual dimorphism in the amphids, which are a single loop 5 µm in diameter. Two opposed reflexed ovaries. Vulva simple, at 55 % of total body length from the anterior end.

Juvenile. Not found.

Diagnosis. Spirinia sophia sp. n. is mainly characterized by somatic papillae not being associated with epidermal glands, and being irregularly distributed over the body. Presence of subcephalic setae, concentration of somatic setae in the neck region while scarce over the rest of the body and the De Man ratio a are also characteristic.

Differential diagnosis. The two new species, Spirinia lara sp. n. and Spirinia sophia sp. n. resemble each other in some characteristics such as body length and presence of subcephalic setae, but differ in body width, the De Man ratio's a, b, and c, the length of somatic setae, spacing of transverse cuticular striation and length of spicules, gubernaculum and tail. Spirinia sophia sp. n. also differs in the irregular arrangement of the somatic papillae (symmetrical in Spirinia lara sp. n.), and by the size and dimorphism of the amphideal fovea.

S. sophia sp. n. is also close to Spirinia gerlachi Luc & de Coninck (1959) in the female body length and De Man ratio's b and c.

Figures

FIGURE 5. Spirinia sophia sp. n., holotype. A: total body, B: anterior end with amphid, striae, and bulb; C: head region with teeth; D: head reagion emphasizing cephalic setae and amphideal fovea; E: tail with spicule, gubernaculum, caudal glands and striae; F: tail with precloacal supplements, ejaculatory glands and papile glands.

FIGURE 6. Spirinia sophia sp. n., allotype. A: total body, B: secretory-excretory gland, nerve ring and bulb; C: head region with cephalic and subcephalic setae, amphideal fovea and striae; D: vulva.

FIGURE 7. Spirinia sophia sp. n. A: Holotype, total body; B: Allotype, total body; C: holotype, amphid; D: allotype, tooth and cephalic setae; E: allotype, amphid; F: holotype, dorsal tooth and outer labial papillae visible; G: tail region; H: Spicule and gubernaculum; I: vulva. Scales A: 50 Μm; B – I: 100 Μm.

Tables

TABLE 3. Male and female measurements (Μm) of Spirinia sophia sp. n.

	holotype	P108	allotype	P109
L	2180	1945	1810	1365
Hd	13	15	13	15
amphid pos	13	7	7	8
Amphid	8	7	5	5
% amph	55	50	50	50
mbd	20	18	24	23
abd	20	24	14	14
pharynx	106	112	109	97
bulb	12	17	17	14
cbd	18	19	21	18
%cbd	67	90	82	77
Spic	27	26
gub	15	12
%V			55	57
tail	91	86	81	116
cs	5	4	5	5
sub c s	4	4	5	5
som s	4	5	5	5
a	112	108	77	58
b	21	17	17	14
c	24	23	22	12
c'	5	4	6	9
annul hd	1	0.5	1	0.5
annul t	0.5	0.5	0.5	0.5
annul mid	1	1	1	1