Two new species of genus Perspiria (Desmodoridae: Nematoda) from the Bohai Bay of China
Author
Zhai, Hongxiu
Author
Shi, Yifeng
Author
Li, Ting
Author
Sun, Jun
text
Journal of Natural History
2023
2023-05-04
57
9 - 12
490
502
http://dx.doi.org/10.1080/00222933.2023.2198149
journal article
10.1080/00222933.2023.2198149
4b9c5f8e-6e38-4ef1-8c33-e8040e92461a
1464-5262
7925394
Perspiria major
sp. nov.
(
Figures 4
,
5
;
Table 2
)
Holotype
and
paratype
material
Two males and
two females
were collected from the subtidal zone of
Bohai Bay
.
Holotype
male on slide BHB40-(0-2)-2.
Paratype
male 2 on slide BHB40-(0-2)-7; female 1 on slide BHB04-(2-5)-8; female 2 on slide BHB41-(0-2)-3.
Figure 4.
Perspiria major
sp. nov.
Male holotype (a, d, e) and female paratypes (b, c): (a, c) lateral view of anterior body portion, showing cephalic setae, amphid, buccal cavity with tooth, cervical setae and pharyngeal bulbs; (b) entire view of female, showing vulva and ovaries; (c) lateral view of female pharyngeal region; (d) magnification drawing of spicules and gubernaculum; (e) lateral view of posterior body portion, showing tail, spicules and gubernaculum.
Figure 5.
Perspiria major
sp. nov.
holotype (a, d) and paratypes (b, c, e): (a, c) lateral view of anterior portion, showing cephalic setae and amphidial fovea; (b) lateral view of pharyngeal region, showing small dorsal tooth (arrow) and pharyngeal bulb; (d) lateral view of male posterior portion, showing tail, spicules and gubernaculum; (e) magnification of spicules; (f) middle region of female, showing vulva and eggs. Scale bars: a, c = 20 µm; b = 15 µm; d, f = 50 µm; e = 10 µm.
Table 2.
Individual measurements of
Perspiria major
sp. nov.
(in µm except ratios a, b, c, c′ and V%).
Holotype |
Paratypes |
Characters |
M1 |
M2 |
F1 |
F2 |
a |
30.8 |
32.9 |
38.7 |
36.1 |
b |
15.4 |
15.2 |
18 |
17.2 |
c |
18.4 |
18.1 |
19.2 |
18.6 |
c̍ |
2.4 |
2,5 |
2.9 |
2.8 |
V |
- |
- |
58.1 |
53 |
Body length |
1914 |
2011 |
2441 |
2239 |
Body diameter |
62 |
61 |
63 |
62 |
Head diameter |
21 |
19 |
21 |
20 |
Cephalic setae length |
6 |
6 |
6 |
6 |
Amphid diameter |
7 |
6 |
7 |
7 |
Nerve ring from anterior |
91 |
83 |
88 |
90 |
Pharynx length |
124 |
132 |
136 |
130 |
Body diameter at the base of pharynx |
44 |
48 |
44 |
51 |
Length of spicules along arc |
52 |
51 |
- |
- |
Length of gubernaculum |
10 |
9 |
- |
- |
Body diameter at cloaca or anus |
43 |
45 |
43 |
42 |
Tail length |
104 |
111 |
127 |
120 |
Vulva from anterior end |
- |
- |
1420 |
1175 |
Body diameter at vulva |
- |
- |
62 |
62 |
Holotype
and
paratype
locality and habitat
Holotype
male
and
paratype
male 2 were collected from
Station
BHB40:
38.416 N
,
118.140 E
; depth
18 m
; temperature 16.18°C; salinity 31.2 psu; silt sediment in the east of
Bohai Bay.
Female 1 was collected from
Station
BHB04:
38.964 N
,
118.328 E
; depth:
7 m
; temperature: 14.9°C; salinity: 30.43 psu; silt sediment in the north of
Bohai Bay.
Female 2 was collected from
Station
BHB41:
38.533 N
,
118.91 E
; depth:
18 m
; temperature: 15.9°C; salinity: 32.0 psu; silt sediment in the east of
Bohai Bay.
Etymology
The species is named in reference to its relatively large body for the genus.
Measurements
All measurement data are given in
Table 2
.
Description
Holotype
male.
Body cylindrical with blunt anterior end and tapered tail end. Cuticle striated, beginning from the level of the middle of amphideal fovea. Inner labial sensilla not observed, six outer labial sensilla papilliform, four cephalic setae thin, about 8 μm long, located level with the middle of the amphideal fovea. Two latero-dorsal and two latero-ventral longitudinal rows of 5–6 cervical setae (4–6 μm long), somatic setae short, arranged irregularly on the surface of the body. Amphideal fovea unispiral, about 7 μm in diameter, i.e. 37% of the corresponding body diameter, and 5 μm from the anterior end. Buccal cavity minute, with a small dorsal tooth. Pharynx 124 μm long, cylindrical, with an oval anterior bulb and a pyriform terminal bulb. Cardia small, conical. Nerve ring located at about 75% of pharyngeal length from anterior end. Ventral gland and excretory pore not observed. Tail conico-cylindrical with prominent transverse striations except its terminal end, 2.5 times cloacal body diameter. Three caudal glands present.
Reproductive system with single outstretched testis. Spicules arcuated without ventral velum, 1.2 cloacal body diameters long, proximal end enlarged, heart-shaped, and distal end tapered. Gubernaculum plate-shaped, 10 µm long, broadest in middle portion and tapering proximally and distally, without apophysis. Precloacal supplements absent.
Females.
Similar to males in most morphological characters except the body slightly larger. Reproductive system didelphic, with two opposed and reflexed ovaries. Anterior ovary located to the right of intestine, posterior ovary to the left of intestine. Spermathecae not observed. Vagina straight, cuticularised, about 0.2 times vulval body diameters long. Vulva raised, situated on ventral side of mid-body, about 55% of body length from anterior end.
Differential diagnosis and discussion
The species is characterised by the presence of four longitudinal rows of 5–6 cervical setae, small unispiral amphidial fovea, partially surrounded with cuticular striation (
Figures 4
(a), 5(b)); conical buccal cavity with a small dorsal tooth; pharynx with an oval anterior bulb and a pyriform terminal bulb; spicules arcuated with heart-shaped proximal end and tapered distal end, without ventral velum. Gubernaculum plate-shaped without apophysis. Precloacal supplement absent. Tail relatively short, conico-cylindrical with prominent transverse striations.
The new species is most similar to
P. megamphida
Vincx and Gourbault,
1989
in having a short tail that is shorter than 3 times cloacal body diameter. However, the new species differs from the latter species by its much smaller amphidial fovea (37% of corresponding body diameter vs more than 60%); the presence of the dorsal tooth (vs absence) and longer body length (1914–2241 μm vs 1605 μm). The difference between the new species and its congeners can be inferred from the key below.
Updated key to all valid species of
Perspiria
including the new species
1. Presence of somatic papillae along the body..................................................................
P. lara
- Absence of somatic papillae along the body............................................................................ 2
2. Male with precloacal supplements................................................................................................ 3
- Male without precloacal supplements ......................................................................................... 5
3. 11–12 tubular precloacal supplements, tail filiform, 8.5–11.2 a.b.d. long ......................... ..................................................................................................................................................
P. flagellata
- 14–17 cup-shaped or papillary precloacal supplements, tail conico-cylindrical, shorter than 8 a.b.d.............................................................................................................................................. 4
4. Amphidial fovea circular, precloacal supplements cup-shaped......................
P. papillata
- Amphidial fovea longitudinal loop-shaped, precloacal supplements papilliform........... ........................................................................................................................
P. macramphida
sp. nov.
5. Cuticle striations resolvable into dots............................................................
P. septentrionalis
- Cuticle striations prominent, not resolvable into dots .......................................................... 6
6. Buccal cavity with two dorsal teeth..................................... .....................................
P. elongata
- Buccal cavity with only one dorsal tooth or no tooth at all................................................ 7
7. Proximal end of spicules markedly hook-shaped......................... .........................
P. hamata
- Proximal end of spicules not hook-like........................................................................................ 8
8. Tail filiform, longer than 9 a.b.d...................................................................................................... 9
- Tail conico-cylindrical, shorter than 8 a.b.d.............................................................................. 11
9. Spicules without ventral velum, gubernaculum with dorsal apophysis.............................. .........................................................................................................................................
P. striaticaudata
- Spicules with ventral velum, gubernaculum without dorsal apophysis....................... 10
10. Tail 11.9–14.5 a.b.d. long, slender spicule with triangular proximal end............................ ........................................................................................................................................
P. longicaudatus
- Tail 9–10 a.b.d. long, thick spicule with rounded or club-shaped proximal end.. ........ .........................................................................................................................................................
P. mokii
11. Tail 6–7.3 a.b.d. long, spicules 36–40 μm................................ ................................
P. boucheri
- Tail shorter than 3 a.b.d., spicules 51–55 μm .......................................................................... 12
12. Amphidial fovea large, 60% c.b.d., buccal cavity without tooth..... .....
P. megamphida
- Amphidial fovea small, 37% c.b.d., buccal cavity with dorsal tooth .................................... ........................................................................................................................................
P. major
sp. nov.