Nematodes of the order Dorylaimida from Romania. The genus Enchodelus Thorne, 1939. 2. Species with rounded tail and medium-sized odontostyle
Author
Ciobanu, Marcel
Institute of Biological Research, Department of Taxonomy and Ecology, 48 Republicii Str., 400015 Cluj-Napoca, Romania & Departamento de Biología Animal, Vegetal y Ecología, Universidad de Jaén, Campus ‘ Las Lagunillas’ s / n, Edificio B 3, 23071 - Jaén, Spain
Author
Popovici, Iuliana
Institute of Biological Research, Department of Taxonomy and Ecology, 48 Republicii Str., 400015 Cluj-Napoca, Romania
Author
Guerrero, Pablo
Departamento de Biología Animal, Vegetal y Ecología, Universidad de Jaén, Campus ‘ Las Lagunillas’ s / n, Edificio B 3, 23071 - Jaén, Spain
Author
Santiago, Reyes Peña-
Departamento de Biología Animal, Vegetal y Ecología, Universidad de Jaén, Campus ‘ Las Lagunillas’ s / n, Edificio B 3, 23071 - Jaén, Spain
text
Nematology
2010
2009-09-28
12
3
381
397
journal article
10.1163/138855409X12549869072329
8111660
Enchodelus parahopedoroides
*
sp. n.
(
Figs 3-5
)
MATERIAL EXAMINED
Three females
from the
Bucegi Mountains
,
three females
from the
Retezat Mountains
,
one male
from
Vlădeasa Mountain
, and
one male
from
Bihor Mountains
, all in acceptable condition.
MEASUREMENTS
See
Table 4.
DESCRIPTION
Female
Moderately slender nematodes of medium size,
1.44- 1.64 mm
long. Habitus after fixation curved ventrad, Cshaped. Body cylindrical, tapering towards both ends, but more so anteriorly. Cuticle 2.0-2.5 µm in anterior region, 2.0-3.0 µm at mid-body and 7.0-7.5 µm on tail; its outer layer with very fine transverse striations and much thinner than inner one, especially on tail. Lateral chord 4.5- 7.0 µm wide or occupying 8-12% of mid-body diam., lacking any particular differentiation. Lateral pores obscure, one dorsal and one ventral pore prominent at odontostyle level. Lip region more or less rounded, offset by a distinct depression, 2.8-3.1 times as broad as high and
ca
one-third (32-36%) of body diam. at neck base. Lips amalgamated, labial and cephalic papillae visible, protruding above cephalic contour. Amphid fovea cup-shaped, opening at level of cephalic depression, occupying 8-10 µm or
ca
one-half (42-51%) of corresponding body diam. Cheilostom curly-bracket-shaped. Odontostyle comparatively robust, 11-14 times as long as wide, 1.5-1.6 times longer than lip region diam. or 1.6-2.0% of total body length, aperture small, 4-5 µm long or 14-17% of total length. Odontophore 1.4-1.6 times as long as odontostyle, with basal thickenings or flanges. Guiding ring double, located at 17-20 µm or 1.0-1.1 times lip region diam. from anterior end. Pharynx consisting of a slender muscular anterior portion expanding gradually, pharyngeal expansion occupying
ca
two-fifths (39-41%) of total neck length and
ca
one-half of corresponding body diam. Pharyngeal gland nuclei located as follows: DN = 64-67; S
1
N
1
obscure; S
1
N
2
= 75-78; S
2
N = 85-87. Cardia rounded conoid, nearly as long as broad, (12-18) × (10-13) µm. Genital system didelphic-amphidelphic, both branches equally and well developed, anterior branch 240- 293 µm, posterior branch 215-280 µm long. Ovaries 53- 140 µm long, not reaching sphincter level; oocytes initially in two or more rows, then in one row. Oviduct 65- 105 µm or 1.2-1.9 corresponding body diam. long, consisting of a slender portion with prismatic cells and a moderately developed
pars dilatata
with visible lumen. Sphincter prominent, located between oviduct and uterus. Uterus long, 133-170 µm or 2.4-3.1 corresponding body diam., sometimes twisted, tripartite,
i.e.
: consisting of a wider proximal region with distinct lumen followed by a narrower and shorter intermediate portion with narrow lumen and surrounded by a cluster of hyaline cells, and ending with a well developed spheroid
pars dilatata distalis
.
Vagina
extending inwards 27-32 µm or 47-58% of body diam.,
pars proximalis
longer than broad, (18-22) × (11-15) µm, with sigmoid to straight walls and enveloped by weak circular musculature;
pars refringens
with (in lateral view) two trapezoidal sclerotisations measuring (3.0- 4.5) × (6-8) µm and with a combined width of 12-15 µm;
pars distalis
4.0-5.0 µm long. Vulva a transverse oval slit, preceded by a shallow depression in body surface. Prerectum 3.9-5.7 and rectum 0.9-1.4 anal body diam. long. Tail rounded conoid, in
one specimen
with a few small saccate bodies, inner cuticle layer marked by radial striation, its ventral margin slightly irregular, barely separated from outer layer. Two pairs of subterminal caudal pores, one subdorsal, another practically lateral.
Male
(see remarks)
General morphology similar to that of female, but with more slender body, narrower lip region and slightly shorter odontophore. Genital system diorchic, with opposed testes. In addition to adcloacal pair at 11 or 10.5 µm from cloacal aperture, presence of series of nine ventromedian supplements 10-24 µm apart, posteriormost supplement located at 31 or 32.5 µm from adcloacal pair, barely in anterior to, or at level of, anterior end of spicules. Spicules well curved ventrad, rather robust,
ca
5.1 or 6.0 times as long as wide or 1.6 or 1.9 anal body diam. long. Lateral guiding pieces 9.5 or 11.5 µm,
ca
4.8 or 3.8 times as long as wide. Tail similar to that of female.
*
The specific epithet indicates the resemblance of this species to
E. hopedoroides
.
Fig. 3.
Enchodelus parahopedoroides
sp. n.
A: Anterior region in median, lateral view; B: Lip region in surface, lateral view; C: Neck; D: Female, posterior body region; E: Female, genital system; F: Female, caudal region; G:
Vagina
; H: Male, posterior body region; I: Male, caudal region; J: Oviduct-uterus junction.
Fig. 4.
Enchodelus parahopedoroides
sp. n.
A, B: Anterior region in median, lateral view; C: Female, posterior body region; D: Female, posterior genital branch; E, F:
Vagina
; G: Oviduct-uterus junction; H: Female, caudal region. (Scale bars: A, B, E, F-H
=
10
µ
m; C, D
=
20
µ m.)
Fig. 5.
Enchodelus parahopedoroides
sp. n.
A, B: Pharyngeal expansion; C, D: Cardia; E: Male, posterior body region; F, G: Male, caudal region. (Scale bars: A, B, E
=
20
µ
m; C, D, F, G
=
10
µ m.)
Table 4.
Morphometric data of
Enchodelus parahopedoroides
sp. n.
All measurements are in
µ m (except L, in mm) and in the format:
mean
±
standard deviation (range).
Character |
Population |
Bucegi Moutains |
Retezat Mountains |
Vlădeasa Moutain |
Bihor Moutains |
(Caraiman Peak) |
(Albele Peak) |
(Dealul Caprei) |
(Padiş) |
Female |
Female |
Male |
Male |
Holotype |
Paratypes |
n |
– |
2 |
3 |
1 |
1 |
L |
1.51 |
1.44, 1.48 |
1.62 ± 0.0 |
1.69 |
1.69 |
(1.61-1.64) |
a |
27.8 |
26.5, 28.9 |
29.4 ± 0.7 |
39.4 |
33.1 |
(28.8-30.2) |
b |
4.7 |
4.8, 4.9 |
5.2 ± 0.3 |
5.4 |
5.2 |
(5.0-5.5) |
c |
63.1 |
65.9, 72.4 |
77.0 ± 3.3 |
51.4 |
60.4 |
(73.4-80) |
cļ |
0.7 |
0.6, 0.7 |
0.7 ± 0.1 |
0.9 |
0.8 |
(0.6-0.8) |
V |
46.2 |
51.0, 52.0 |
46.0 ± 1.4 |
– |
– |
(44.5-47.3) |
Lip region diam. |
17.5 |
18, 18.5 |
17.2 ± 0.3 |
13.5 |
13.5 |
(17-17.5) |
Odontostyle length |
28 |
29, 29 |
26.3 ± 0.6 |
28? |
29 |
(26-27) |
Odontophore length |
41 |
40, 43 |
41.7 ± 1.5 |
34 |
39 |
(40-43) |
Guiding ring from ant. end |
17.5 |
17.5, 20 |
18.0 ± 1.3 |
14.5 |
16 |
(17-19.5) |
Neck length |
320 |
304, 305 |
313.7 ± 14.0 |
315 |
322 |
(300-328) |
Pharyngeal expansion length |
130 |
120, 123 |
125.0 ± 3.5 |
120 |
137 |
(123-129) |
Diam. at neck base |
55 |
50, 54 |
49.7 ± 1.5 |
41 |
46 |
(48-51) |
at mid-body |
55 |
50, 56 |
55.3 ± 1.5 |
43 |
51 |
(54-57) |
at anus |
33 |
33, 33 |
29.5 ± 4.0 |
36 |
36 |
(25-33) |
Prerectum length |
128 |
155, 180 |
172.8 ± 17.3 |
– |
– |
(153-185) |
Rectum length |
40 |
34, 38 |
33.3 ± 7.6 |
44? |
35? |
(28-42) |
Tail length |
24 |
20, 23 |
21.2 ± 0.8 |
33 |
28 |
(21-22) |
Spicule length |
– |
– |
– |
59 |
67 |
Ventromedian supplements |
– |
– |
– |
9 |
9 |
DIAGNOSIS AND RELATIONSHIPS
Enchodelus parahopedoroides
sp. n.
is distinguished by its
1.44-1.64 mm
long body, lip region 17.0-18.5 µm diam. and offset by a marked depression, odontostyle 26-28 µm or 1.5-1.6 lip region diam. long and 1.6- 2.0% of total body length, odontophore 40-43 µm long and with distinct basal knobs and flanges, neck 300- 328 µm long, pharyngeal expansion 120-130 µm long or 39-41% of total neck length, female genital system amphidelphic, uterus long and tripartite,
pars refringens vaginae
with two trapezoidal sclerotisations, V = 45- 52, tail rounded conoid (20-24 µm long, c = 63-80,
cļ
= 0.6-0.8), spicules 59-67 µm long, and nine spaced ventromedian supplements starting just anterior to, or at level of, anterior end of spicules.
Enchodelus parahopedoroides
sp. n.
is very similar to
E. hopedoroides
Altherr, 1963
(see description by
Guerrero
et al.
, 2008b
), from which it differs in its narrower lateral chord (4.5-7.0 µm or 8-12% of body diam.
vs
8-16 µm or 11-27% of body diam., respectively), shorter odontostyle (26-28
vs
31-34 µm, n = 23),
pars refringens vaginae
without
vs
with two massive and granular appearing pieces, vulva more posterior (
V
= 45-52
vs
= 40-47), and female tail lacking abundant saccate bodies and any peculiar differentiation of the cuticle
vs
saccate bodies abundant and inner cuticle layer divided into two by a discontinuity, its ventral margin rather irregular and somewhat separated from the outer layer. In spite of the high similarity between both species, there are three features (odontostyle length, nature of
pars refringens vaginae
and female tail) that support the proposal of a new taxon for the Romanian material.
In having an odontostyle less than 30 µm long and rounded tail, the new species is also close to
E. altherri
Vinciguerra & de Francisci, 1973
,
E. ameliae
Guerrero, Liébanas & Peña-Santiago, 2008
,
E. analatus
(Ditlevsen, 1927)
Thorne, 1939
,
E. arcticus
Nesterov, 1976
,
E. georgiensis
Eliava, Tskitishvili & Bagathuria, 2006
,
E. hopedorus
(Thorne, 1929)
Thorne, 1939
,
E. longispiculus
Guerrero, Liébanas & Peña-Santiago, 2008
and
E. ponorensis
Popovici, 1995
. It differs from
E. altherri
in its longer body (
vs
1.18-1.38 mm
), comparatively longer odontostyle at 1.5-1.6
vs
1.8-2.0 lip region diam. long (
i.e
., 1.8 according to the original
Figure 2
A
of
E. altherri
and 2.0 according to the original description), longer neck (
vs
236-276 µm, as calculated from original description), vagina with well developed
pars refringens
(
vs
“vulva debolmente ispessita”), tail of both female and male more rounded
vs
conoid, shorter (
vs
c = 41- 59,
cļ
= 1.0, calculated from original illustrations) and lacking saccate bodies
vs
3-8 saccate bodies present, and longer spicules (
vs
50-52 µm). From
E. ameliae
in its less marked lip region (
vs
offset by constriction), shorter odontostyle (
vs
30-33 µm, n = 11, including females and males), longer neck (
vs
268-307 µm) and pharyngeal expansion (
vs
95-107 µm), and fewer (
vs
11-14) ventromedian supplements, the posteriormost located barely anterior to, or at level of, the anterior end of the spicules
vs
one or two within the range of the spicules. From
E. analatus
in its shorter odontostyle (
vs
30-34 µm),
pars refringens vaginae
present
vs
absent and shorter female tail (
vs
c = 40-55,
cļ
= 0.8-1.1) which lacks
vs
presence of saccate bodies. From
E. arcticus
in its broader lip region (
vs
12 µm, as inferred from original description), longer odontophore (
vs
up to 36 µm, as inferred from original description) and ventromedian supplements present
vs
reportedly absent (!). From
E. georgiensis
in its longer body (
vs
0.88-1.10 mm
), broader lip region (
vs
12 µm), longer odontophore (
vs
35-37 µm) and longer spicules (
vs
36- 44 µm). From
E. hopedorus
in its broader female lip region (
vs
14.5-16 µm), comparatively shorter odontostyle (
vs
1.9-2.2 times the lip region diam.), longer pharyngeal expansion (
vs
33-38% of total neck length) and shorter female tail (
vs
27-39 µm, c = 41-53) lacking
vs
bearing abundant saccate bodies. From
E. longispiculus
in its more slender body (a = 26-30
vs
17-25; body diam. at mid-body = 50-57
vs
64-80 µm), longer pharyngeal expansion (
vs
77-114 µm or 28-37% of total neck length, n = 40), somewhat more posterior vulva (
vs
V
= 41- 48) and posteriormost ventromedian supplement located barely anterior to, or at level of, anterior end of spicules (
vs
two posteriormost, occasionally only one, within range of spicules). Finally, from
E. ponorensis
, the other Romanian species, in its shorter body (
vs
1.6-2.1 mm
), narrower lateral chord (
vs
one-fourth of mid-body diam.) broader female lip region (
vs
15-16 µm), longer odontostyle (
vs
23-25 µm), uterus tripartite
vs
bipartite, and shorter female tail (
vs
35-45 µm, c = 41-56,
cļ
= 0.9- 1.3).
TYPE HABITAT AND LOCALITY
Cliff vegetation, Caraiman Peak, Bucegi Mountains (Southern Romanian Carpathians); site
5 in
Table 1.
OTHER HABITATS AND LOCALITIES
Cliff vegetation on Albele Peak, Retezat Mountains (Southern Romanian Carpathians), mountainous grassland at Dealul Caprei, Vlădeasa Mountain (Western Romanian Carpathians) and spruce forest in a swamp area on the Padiş karstic plateau, Bihor Mountains (Western Romanian Carpathians); sites 9, 11 and
4 in
Table 1.
TYPE MATERIAL
Holotype
female
on slide 1317 and
one
paratype
female
(1318/c) deposited in the nematode collection of the Institute of Biological Research,
Cluj-Napoca
,
Romania
.
Slide 1316 containing
one
paratype
female
deposited in the nematode collection of Departamento de Biología Animal, Biología Vegetal y Ecología, University of Jaén,
Spain
.
REMARKS
Some doubts persist as to the conspecifity of the
two males
examined, which were collected from the Vlădeasa and Bihor Mountains whilst the females came from the Bucegi and Retezat Mountains, as there are some morphometrical differences, particularly their narrower lip region in addition to their different geographical origin. Nevertheless, some significant features, such as odontostyle and pharyngeal expansion lengths are similar to those found in females and serve to distinguish the males from
E. longispiculus
, the most similar species. In addition, as mentioned above, the male posteriormost ventromedian supplement is located barely anterior to, or at level of, the anterior end of the spicule, whereas in other species at least one ventromedian supplement is present within the range of the spicules. Thus, the males are provisionally considered to belong to the same species as the females from Bucegi and Retezat Mountains.