Laimella ferreroi, Barnes & Kim & Lee, 2012

Barnes, Natalie, Kim, Hyeong Geun & Lee, Wonchoel, 2012, New species of free-living marine Sabatieriinae (Nematoda: Monhysterida: Comesomatidae) from around South Korea *, Zootaxa 3368 (1), pp. 263-290 : 268-270

Laimella ferreroi sp. nov.

( Fig. 1 )

Type locality. Sub-tidally north-west of Socotra Rock (32.1523º N 125.1519 º E), at a depth of 51 m, in muddy sediment .

Type material. Holotype male NIBRIV0000245036, collected by Kwang-Soo Kim, in June 2011, from Research Vessel Tam-Gu 8.

Measurements. See Table 3 and 4 for detailed measurements and calculations.

5 155 - 992 1678 906 2283

male 1

11 31 33 25

Description. Male holotype ( Fig. 1 ). Habitus elongate tubular, tapering to filiform tail posteriorly, anterior only slightly narrowed, blunt. Cuticle with faint but relatively coarse striation throughout body, tail appears smooth. Body diameter increases gradually from cephalic setae to mid-esophageal region, reduces slightly behind cardia, then approximately stable to cloaca. Tail conico-cylindrical, cylindrical section filiform, tail tip missing.

Labia as 6 small lips, labial papillae minute, 1 µm long. Six anterior cephalic setae (0.7 hd long) located about 0.2 hd from anterior extremity, 4 posterior cephalic setae (1 hd long) immediated behind. Amphid multi-spiralled with 3.5 turns (diameter 0.7 cbd), 0.5 hd from anterior. Cervical setae about 10 µm long, one setae 2.3 hd from anterior, then sub-lateral pair 3.5 hd from anterior. Somatic setae rare, 0.1–0.3 cbd. Row of latero-ventral postcloacal setae, 6 µm long. Last setae observed 5 abd from the cloaca in cylindrical part of tail.

Anterior section of buccal cavity shallow V-shape (2 µm deep) and posterior portion as undifferentiated collapsed tube, teeth not observed. Oesophageal musculature surrounds buccal cavity, sclerotization of oesophageal lumen not observed. Oesophagus narrow cylindrical tube until slender oesophageal bulb (20 % of oesophagus length), lining of bulb lumen not thickened. Cardia short (12 µm long). Nerve-ring at 48 % oesophageal length from anterior, ventral pore posterior to nerve ring (68 % of oesophageal length). Ventral gland large, round, distance from pore to base of gland 85 µm (55 % of oesophageal length).

Diorchic, outstretched testes, anterior testis 992 µm long, posterior testis 906 µm long. Spicules acutely arcuate (1.3 abd long, measured as curve), gubernaculum with posteriorly directed paired apophyses (0.9 abd long). One short mid-ventral papilla (1 µm long) located 0.4 abd anterior to cloaca. Twelve minute precloacal supplements observed, posterior supplement 1.1 abd from cloaca, anterior supplement 11.0 abd from cloaca. Cloaca as lateral slit. Caudal glands not observed. Five ejaculatory glands anterior to cloacal, 2 left lateral, 3 right lateral. Tail tip missing, but intact extent of tail 24.5 abd long, with filiform cylindrical portion 81 % of total. Terminal setae not observed.

Female. Unknown.

Etymology. The species is named in honour of Dr Tim Ferrero (Natural History Museum, London), as a recognition to his contribution to the field of marine nematodology.

Affinities. Although only one specimen of Laimella ferreori sp. nov. was found, it is the most distinctive of the new Laimella species described here. It differs from other known species by having the largest de Man's ratios a and b (even when accounting for the long tail [L'/mbd and L'/O]). It also has the longest relative gubernaculum so far recorded and the longest, truly filiform, tail. These differences are greater than that which might be found as intraspecific variability.

Figures

FIGURE 1. Laimella ferreroi sp. nov., holotype male: A, oesophagus; B, head; C, pre-cloacal region; D, tail; E, habitus. Scale bars: 10 µm (A–D) and 100 µm (E).