Four new Paramphimonhystrella species (Nematoda: Xyalidae) from the continental slope of New Zealand
Author
Leduc, Daniel
text
Zootaxa
2014
3814
4
478
494
journal article
45523
10.11646/zootaxa.3814.4.2
1f0c9e98-3d8e-4c08-8b80-2e375bfaf6fe
1175-5326
231397
84CD1F7F-9E65-48F3-BE24-C8815264671A
Paramphimonhystrella echinocauda
n. sp.
(
Fig 10
,
Table 2
)
Type
specimen.
Holotype
male (
NIWA
89979), collected on
15 April 2010
(
NIWA
cruise TAN1004, station 4), open slope habitat on southern Hikurangi Margin (
175.6642ºE
,
41.6837ºS
); water depth:
1046 m
.
Etymology.
The species name is derived from the the greek word
echinos
(= spiky) and the latin word
cauda
(= tail), and refers to the presence of several long setae on the tail of this species.
Description.
Male
. Body cylindrical, tapering slightly towards both extremities. Cuticle ~0.8 µm thick, with fine striations ~1.2 µm apart beginning halfway between cephalic setae and anterior edge of amphids. Somatic setae ~4 µm long, sparse, irregularly arranged. Head tapering anteriorly. Inner labial sensillae not observed; six outer labial setae, ~1.5 µm long, situated immediately anterior to four cephalic setae, 2 µm long. Two rings of subcephalic setae; anterior ring consists of eight setae at level of amphids, 2 µm long; second ring consists of ten setae 3–7 µm long, situated ~0.5 cbd posterior to first ring of sub-cephalic setae (
Figure 10
A, B). Amphids with round or slightly oval outline, lightly cuticularised. Buccal cavity 7 µm deep, 4 µm wide, with cylindrical anterior portion and funnel-shaped posterior portion, completely surrounded by pharyngeal tissue. Pharynx muscular, widening slightly posteriorly but not forming true bulb. Cardia elongated, ~9 µm long, surrounded by intestine tissue. Nerve situated at 44% of pharynx length from anterior. Secretory-excretory system not observed.
Male reproductive system diorchic with outstretched testes; both testes situated to the left of intestine. Sperm cells large, globular in shape, ~7–9 × 5–7 µm. Spicules slightly curved, 1.8 abd long, lightly cuticularised, with slender proximal portion and widening distally, distal tip with three pointed projections (
Figure 7
D); gubernaculum present, thin, parallel to spicules; pre-cloacal supplements absent. Tail conico-cylindrical, with several setae in middle portion, 6–13 µm long. Two lateral setae near tail tip, 6–7 µm long, and one terminal seta, 7 µm long. Three caudal gland; anterior-most gland conspicuously larger than other two (
Figure 10
E).
Diagnosis.
P. echinocauda
n. sp.
is characterised by buccal cavity with cylindrical anterior portion and funnelshaped posterior portion, round amphids, two rings of 8–10 sub-cephalic setae, distal tip of slender spicules with three pointed projections, thin gubernaculum, and tail with several long setae in middle portion, two lateral setae near tail tip and one terminal seta.
Differential diagnosis.
P. echinocauda
n. sp.
can be differentiated from all other species of the genus by the spicules with slender proximal portion and distal tip with three pointed projections, and by the tail with several long setae in middle portion, two lateral setae near tail tip, and one terminal seta.