FRESHWATER NEMATODES FROM LOCH NESS 



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Fig. 33 Diplogasteritus nudicapitatus (Steiner, 1914). A-C. male. A. 

 habitus; B, spicular region; C. oesophageal region. Scale bars a = 20 

 urn, b = 50 um. 



MALE. (N =1 ). L = 637 um; a = 25; b = 6.3; c = 4.0; c' = 8.5: 

 gubernaculum = 25.6 um; spicule = 33 um; tail = 155 um. 



Head not offset; labial papillae minute. Amphids not seen. Cuticle 

 with ca. 20 prominent longitudinal lines. Annules minute, less than 



0.8um wide. Oesophagus with large median bulb and smaller basal 

 bulb; 105 um long. Excretory pore 98um from anterior, at mid-level 

 of basal bulb. Testis anteriorly directed with reflexed tip. Spicula 1.8 

 times anal body width. Gubernaculum, distally with two pairs of 

 mound-like swellings (arrowed, fig. 36H). Bursa absent. Nine pairs 

 of caudal papillae; three pairs pre-anal and six post-anal. 



Distribution and habitat. A common species found in Europe 

 and South Africa in terrestrial and aquatic habitats. 



Remarks. Morphology and measurements closely agree with the 

 descriptions of D. nudicapitatus provided by Bongers (1988) and 

 Zullini (1982). 



Eucephalobus oxyuroides (de Man, 1876) Steiner, 1936. 



(Figs 34, 36E-G) 



Material examined. Foyers Plateau: 161 m; core 19, 1 ?. River 

 Oich: 0.17 m; core 36, 19. 



Females. (n = 2).L = 558, 615 jam; a = 23.5, 19.6: b = 3.6, 3.9; c 

 = 6.5. 7.7; c' = 6.6. 4.8; V = 55.5, 61 : tail 85, 79.3 um. 



Cuticle 1 .9 um thick with annules 1 .4, 2. 1 um wide at mid-body. 

 Lips six, pointed. Lateral fields with three lines ending at level of 

 phasmids. Stoma (n = 1 ) 14.7um long, rhabdions distinct. Oesopha- 

 gus cylindrical, 153, 157 um long, basal bulb ovate. Excretory pore 

 (n=l) 91 um from anterior end at level of hemizonid. Reproductive 

 system monodelphic, prodelphic. Reflexed at oviduct. Spermatheca 

 and postuterine sac not seen. Vagina length about one half of vulval 

 body width. Vulva not protruding. Rectum 23, 26 um long or 1 .8, 1 .6 

 times anal body width. Tail 80-86um long. Phasmid at 28, 32% of 

 tail length. 



Fig. 34 Eucephalobus oxyuroides (de Man, 1 876). A, B, E, F, female 1 . 

 A, tail; B, anterior region: E, vulval region; F, habitus. C, D, female 2. 

 C, habitus: D. tail. Scale bars a = 20 um. b = 100 um. 



Fig. 35 Eucephalobus sp. A-D, female. A,oesophageal region; B. 

 reproductive system; C, tail; D, habitus. Scale bars a = 20 fim, b = 

 um. 



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