10 



F.R. WANLESS AND R. HUNTER 



Remarks. This nematode is close to F. butteus (Thorne & Malek, 

 1968) Brzeski, 1997, but the tail is longer and differs in shape. 



Filenchus sp. 3 



(Fig. 11) 



Material examined. Fort Augustus Bay: 92 m; core 3, 1 6. 



MALE, (n = 1). L = 434 urn; a = 35.7; b = 6.4; c = 4.4; c' = 10.3; 

 gubernaculum = 5.8 urn; spicules = 15 um; tail = 99 urn. 



Head 5.0 um wide at base with 3-4 annules. Amphids not 

 observed. Annules fine about 0.9 um at mid-body. Lateral field with 

 four lateral lines, hardly evident. Spear moderately slender, 1 1 .2 um 

 long with small basal knobs 1.9 um wide. Excretory pore 61.4 um 

 from anterior. Oesophagus poorly preserved, about 68 um long; 

 median bulb ovoid, valves not observed, centre at about 59% of 

 oesophageal length. Testis 138 um long, occupying 32% of body 

 length, bursa adanal, about 19 um long, with fine crenated margins. 

 Tail tip pointed. 



Remarks. No conclusion can be reached on the specific identity 

 of this specimen. It is close to F.thornei, but differs by its shorter 

 body length, spicules and tail. 



Lelenchus leptosoma (de Man, 1880) Raski & Geraert, 

 1985 



(Figs 12, 36B) 



Material examined. Fort Augustus Bay: 92 m; core 3; 1 9. Deep 

 South Basin: 194 m; core 13; 1 9. Foyers Plateau: 159, 160 m; cores 



14, 15; 3 99. 



Females, (n = 5). L = 546 (487-583) um; a = 46.6 (40-49.8); 

 b = 5.5 (4.9-6.3); c = 3.1 (2.7-3.35); c' = 24.8 (22-27.9); V = 52 



Fig. 12 Lelenchus leptosoma (de Man. 1880). A-E. female. A, 



oesophageal region: B. head showing amphid; C. posterior region: D. 

 habitus; E. reproductive system. Scale bars a = 20 pm. b = 10 pm. c = 

 60 um, d= 100 um. 



Fig. 11 Filenchus sp. 3. A-E, male. A, oesophageal region: B, lateral 

 field; C, spicular region: D. habitus; E, tail and spicular region. Scale 

 bars a = 20 pm, b = 100 pm. 



(48-54.8); V = 77.6 (75.5-78); tail/V-a = 2.2 (1.9-2.5); tail = 180 

 um (156-215). 



Cephalic region narrowed dorso-ventrally. Cuticle smooth by 

 light microscopy. Amphids sinuous. Lateral field absent. Spear 

 slender, 7.7-9.3 um long with small rounded knobs about 1.4 um 

 wide. Oesophagus 88-108 um long; median bulb spindle-shaped 

 with valves at 41-43% of oesophageal length. Anterior genital 

 branch 96.7-121.5 um long. Spermatheca more or less bispherical 

 with rounded sperm (absent in one specimen) about 1.3 um in 

 diameter. Postuterine sac not evident in any specimen, possibly 

 collapsed. Vagina about 5.5 um long with thin walls, curved 

 anteriorly. 



Distribution and habitat. Cosmopolitan; soils and freshwater. 



Remarks. These specimens, for the most part, agree with the 

 description and morphometries presented in the literature (Raski & 

 Geraert, 1985). Minor differences slightly extending the range of 

 several ratios are not considered to be of any significance. 



Lelenchus sp. 



(Figs 13. 36A) 



Material examined. Deep South Basin: 195, 204 m; cores 9, 11; 

 2 99. Foyers Plateau: 157, 159 m; cores 14, 16; lcJ, 1 9. 



FEMALES, (n = 3). L = 620 (5 12-763) um; a = 47.4 (42-54.5); b = 

 6.0 (5.5-6.5); c = 3.5 (3.3-3.8); c' = 22.8 (21.4-24); V = 57.6 (57- 

 58); V = 81 (80-82); tail/V-a = 2.1 (1.8-2.4); tail = 173 (154-200) 

 um. 



