Stegelleta mucronata, A..L O O F, 1971

P. A. A. LOOF, 1971, FREELIVING AND PLANT PARASITIC NEMATODES FROM SPITZBERGEN, COLLECTED BY MR. H. VAN ROSSEN, Mededelingen Landbouwhogeschool Wageningen 71, pp. 1-86 : 21

Stegelleta mucronata n.sp.

( Fig. 2A ).

Females (n = 9): L = 0.32- 0.40 mm; a = 16-20; b = 3.3 -4. 1; c = 13 - 15; V = 1 5 - 2163 - 6610 - 19.

Female, holotype: L = 0.37 mm; a = 19; b = 3.5; c = 13; V = 166613.

Male not found.

Body somewhat slenderer than in Acrobeles and Cervidellus , but of same shape. Transverse striation very coarse, 2.7 \i in mid-body. The excretory pore lies on the 29th-33rd annule; there are 62 -67 annules between excretory pore and vulva, 38 -43 between vulva and anus and 12-15 on the tail. Total annule number = 147-154. Number of longitudinal grooves about 20-24. Lateral field with two wings (three longitudinal grooves). Labial probolae well developed, acute, with sclerotized edges; between them some sclerotized points. Prelabial probolae setiform, bifurcate over about one-third of their length, the prongs slightly recurved. Corpus of oesophagus 2.5 X as long as isthmus, with slight fusiform swelling; not offset by alteration of tissues from the isthmus. The terminal bulb fills almost the whole body cavity and measures 60 % of corresponding body width. The nerve ring surrounds the isthmus in its middle. Hemizonid conspicuous, two annules long. Excretory pore immediately anterior to hemizonid. Vulva lips hardly protruding. Gonad cephaloboid, the double postvulvar flexure in some specimens not present. Dimensions of an intra-uterine egg: 48 X 19 (J.. Tail conoid, 1.9-2.4 anal body widths long, the tip mucronate, irregular.

Holotype: Female on slide WT 1212 . Paratypes: Eight females on slides WT 1213-1214 .

Type habitat and locality: Sample 53. Paratypes also from sample 18.

This species differs from. S.cancellata ( Thorne, 1925) and S.tuarua Yeates, 1967 by the shape of the prelabial probolae; from S.iketaia Yeates, 1967 and S.ophioglossa Andrâssy , 19671 by the short tail; from S.incisa (Thorne, 1937) by shape of the labial and prelabial probolae and the tapering tail; from S. argentinica Andrâssy, 1963 (of which only males are known) by the presence of a fusiform swelling in the corpus; from S.lineata ( Thorne, 1925) by the larger terminal bulb, relatively longer tail and irregular terminus.

Figures

FIG. 2. A: Stegelleta mucronata n.sp., female; B: Cervidellus serratus (Thorne), female.