Deep-sea Echinoderidae (Kinorhyncha: Cyclorhagida) from the Northwest Pacific
Author
Sørensen, Martin V.
4143D650-12FC-4914-93F5-2C39339A7156
Section for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, DK- 1350 Copenhagen, Denmark. Harte Research Institute, Texas A & M University - Corpus Christi, Corpus Christi, TX 78412, USA. Department of Earth, Ocean and Atmospheric Sciences, Florida State University, Tallahassee, FL 32306 - 4520, USA.
mvsorensen@snm.ku.dk
Author
Rohal, Melissa
FE6165E7-AF07-4751-A3BE-453A48A700B6
mrohal@islander.tamucc.edu
Author
Thistle, David
B388C0B0-2D25-43B2-A518-5360A45ABC72
dthistle@fsu.edu
text
European Journal of Taxonomy
2018
2018-08-17
456
1
75
journal article
22296
10.5852/ejt.2018.456
0566a11e-d6a3-4283-89c7-c7feea96fdbf
3817823
DE1B1DEE-9871-4803-9F67-025F2B439560
Echinoderes lupherorum
sp. nov.
urn:lsid:zoobank.org:act:
B3E96033-83C3-4924-8FFE-3592E427620C
Figs 18–20
,
Tables 12–13
Diagnosis
Echinoderes
with middorsal spines on segments 4 to 8, and spines in lateroventral positions on segments 6 to 9. Tubes present in lateroventral positions on segments 2 and 5, and in midlateral positions of segment 10. Very minute glandular cell outlets
type
2 present in subdorsal positions on segment 2 and in laterodorsal positions on segments 8 and 9. Tergal plate of segment 11 terminates in pointed, acicular tergal extensions, constituting 6 to 8% of trunk length. Males with three pairs of penile spines; females with long lateral terminal accessory spines, and papillae in ventrolateral positions of segment 7 and ventromedial positions of segment 8.
Etymology
The second author (MR) dedicates this species to her fiancé Brach Lupher and the Lupher family – her family to be.
Material examined
Holotype
UNITED STATES OF AMERICA
: adult
♀
,
US
West Coast
, off southern
Oregon
,
42°33′50″ N
,
131°59′48″ W
,
St.
2, 3601 m deep, collected from mud,
17 Sep. 2008
, mounted in
Fluoromount G
on an H-S slide (NHMD-225220).
See
Fig. 1
for localities and
Table 1
for detailed station data.
Paratypes
UNITED STATES OF AMERICA
:
4 ♀♀
, 1 ♂, same collecting data as for
holotype
;
1 ♀
, St. 3 (NHMD- 225221–225226). All
paratypes
are mounted in Fluoromount G, three on H-S slides and three on glass slides.
Additional non-type material
UNITED STATES OF AMERICA
:
3 ♀♀
, 4 ♂♂, St. 6, mounted for SEM and stored in the first author’s personal reference collection.
Description
Adults with head, neck and eleven trunk segments (
Figs 18
A–B, 19A, 20A–B). The trunk is relatively large, appears slender, tapered in both ends, and broadest from segment 5 to 8. Lateral terminal spines are long and slender (
Fig. 18C
), from 80% and up to same length as the trunk, and lateral terminal accessory spines in females are shorter (
Figs 18
A–B), around 20% of the lateral terminal spine length. For a complete overview of measurements and dimensions, see
Table 12
. Distribution of cuticular structures, i.e., sensory spots, glandular cell outlets, spines and tubes, is summarized in
Table 13
.
The head consists of a retractable mouth cone and an introvert. Inner oral styles are present, but their exact number and arrangement could not be determined. The external mouth cone armature consists of nine outer oral styles, each with four or five basal fringe tips. The introvert sectors are defined by ten primary spinoscalids in Ring 01. Each primary spinoscalid consists of a basal sheath and a distal end piece with a blunt tip (
Fig. 20C
). The basal sheaths have marginal extensions forming two layers of transverse fringes. End pieces are smooth. The arrangement of scalids follows the same pattern as in
Echinoderes hviidarum
sp. nov.
described above; hence, see
Fig. 11
for a complete overview. All spinoscalids consist of a basal sheath and a pointed end piece. The basal sheaths terminate in fringed margins in spinoscalids of Rings 02 and 04, whereas the sheaths of Ring 03 have a median spike only. Spinoscalids of Rings 05 to 07 are composed as those in the preceding ring, but with shorter end pieces (
Figs 11
,
20C
).
Fig. 18.
Line art illustrations of
Echinoderes lupherorum
sp. nov.
A
. ♀, dorsal view.
B
. ♀, ventral view.
C
. ♀, segments 10 to 11, with lateral terminal spines drawn in full length, dorsal view.
D
. ♂, segments 10 to 11, dorsal view.
E
. ♂, segments 10 to 11, ventral view. Abbreviations: fpa = female papillae; ldgco2 = laterodorsal glandular cell outlet type 2; ltas = lateral terminal accessory spine; lts = lateral terminal spine; lvs = lateroventral spine; lvt = lateroventral tube; mdgco1 = middorsal glandular cell outlet type 1; mds = middorsal spine; mlss = midlateral sensory spot; mlt = midlateral tube; pe = penile spines; sdgco2 = subdorsal glandular cell outlet type 2; sdss = subdorsal sensory spot; si = sieve plate; slss = sublateral sensory spot; te = tergal extension.
Fig. 19.
Light micrographs showing overviews and details of
Echinoderes lupherorum
sp. nov.
, holotype, ♀ (A–C, H) (NHMD-225220), paratype, ♀ (D–G) (NHMD-225226) and paratype, ♂ (I–J) (NHMD-225225).
A
. Ventral overview.
B
. Segments 1 to 3, dorsal view.
C
. Segments 1 to 3, ventral view.
D
. Segments 3 to 6, dorsal view.
E
. Segments 3 to 6, ventral view.
F
. Segments 8 to 9, dorsal view.
G
. Segments 7 to 8, ventral view.
H
. ♀, segments 10 to 11, ventral view.
I
. ♂, segments 10 to 11, dorsal view.
J
. ♂, segments 10 to 11, ventral view. Abbreviations: fpa = female papillae; ldgco2 = laterodorsal glandular cell outlet type 2; ldss = laterodorsal sensory spot; ltas = lateral terminal accessory spine; lts = lateral terminal spine; lvs = lateroventral spine; lvt = lateroventral tube; mds = middorsal spine; mlt = midlateral tube; pdss = paradorsal sensory spot; pe = penile spine; sdgco1/2 = subdorsal glandular cell outlet type 1 or 2; sdss = subdorsal sensory spot; te = tergal extensions; vmss = ventromedial sensory spot.
Fig. 20.
Scanning electron micrographs showing overviews and details of
Echinoderes lupherorum
sp. nov.
A
. Lateroventral overview.
B
. Laterodorsal overview.
C
. Introvert sectors 10 and 9.
D
. Segments 1 to 3, ventral view.
E
. Segments 1 to 2, dorsal view.
F
. Detail showing middorsal (right) to laterodorsal (left) parts of segments 1 and 2. Inset shows close-up of subdorsal glandular cell outlet type 2; scale = 1 µm.
G
. Detail showing middorsal (right) to laterodorsal (left) parts of 8.
H
. Close-up showing laterodorsal sensory spot and glandular cell outlet type 2 on segment 8.
I
. Segments 9 to 10, lateral view.
J
. ♀, segments 10 to 11, dorsal view. Abbreviations: ldgco2 = laterodorsal glandular cell outlet type 2; ldss = laterodorsal sensory spot; lts = lateral terminal spine; lvt = lateroventral tube; mds = middorsal spine; mdss = middorsal sensory spot; mlt = midlateral tube; pdss = paradorsal sensory spot; psp = primary spinoscalid; sdgco2 = subdorsal glandular cell outlet type 2; sdss = subdorsal sensory spot; sp = spinoscalid followed by introvert ring number; te = tergal extensions; tr = trichoscalid.
Table 12.
Measurements from light microscopy of
Echinoderes lupherorum
sp. nov.
(in µm), including number of measured specimens (n) and standard deviation (SD). Abbreviations: (ac) = acicular spine; LTAS = lateral terminal accessory spine; LTS = lateral terminal spine; LV = lateroventral; MD = middorsal; ML = midlateral; MSW-8 = maximum sternal width, measured on segment 8 in this species; S = segment lengths; SW-10 = standard width, always measured on segment 10; TE = tergal extension; TL = trunk length; (tu) = tube.
Character
|
n
|
Range
|
Mean
|
SD
|
TL |
7 |
331–415 |
371 |
36.42 |
MSW-8 |
6 |
75–81 |
78 |
2.16 |
MSW-8/TL |
6 |
19.3–23.9% |
21.0% |
1.83% |
SW-10 |
6 |
65–71 |
67 |
2.58 |
SW-10/TL |
6 |
15.7–20.2% |
18.1% |
1.77% |
S1 |
7 |
35–42 |
39 |
2.54 |
S2 |
7 |
33–37 |
35 |
1.46 |
S3 |
7 |
39–43 |
41 |
1.50 |
S4 |
7 |
42–47 |
45 |
1.90 |
S5 |
7 |
42–52 |
48 |
3.78 |
S6 |
7 |
50–57 |
54 |
2.70 |
S7 |
7 |
54–60 |
57 |
2.34 |
S8 |
7 |
54–62 |
59 |
2.82 |
S9 |
7 |
59–62 |
61 |
1.38 |
S10 |
7 |
44–51 |
49 |
2.51 |
S11 |
7 |
53–58 |
56 |
1.91 |
MD4 (ac) |
7 |
31–36 |
33 |
1.95 |
MD5 (ac) |
6 |
40–48 |
44 |
3.27 |
MD6 (ac) |
7 |
50–67 |
54 |
6.00 |
MD7 (ac) |
6 |
54–83 |
70 |
11.15 |
MD8 (ac) |
6 |
90–128 |
112 |
16.97 |
LV6 (ac) |
6 |
32–43 |
38 |
4.32 |
LV7 (ac) |
7 |
45–53 |
48 |
3.86 |
LV8 (ac) |
7 |
53–68 |
60 |
5.77 |
LV9 (ac) |
7 |
54–74 |
64 |
7.63 |
ML10 (tu) |
6 |
29–34 |
31 |
1.75 |
TE |
7 |
24–28 |
26 |
1.40 |
TE/TL |
7 |
6.0–8.2% |
7.2% |
0.94% |
LTS |
6 |
324–355 |
341 |
12.45 |
LTS/TL |
6 |
80.5–100.9% |
91.5% |
7.59% |
LTAS |
6 |
62–83 |
75 |
7.40 |
The neck has 16 placids, measuring
18 µm
in length, except for the slightly longer midventral ones, measuring
20 µm
in length. The midventral placid is also broadest, measuring
16 µm
in width at its base, whereas all others are narrower, measuring
10 µm
in width at their bases. Four dorsal and two ventral trichoscalid plates are present; trichoscalid plates are fairly small, and rounded to oval.
Segment 1 consists of a complete cuticular ring. Sensory spots are located on the anterior half of the segment, but not at the anterior margin in subdorsal and laterodorsal positions (
Figs 18A
,
19B
,
20E
); sensory spots are small and rounded, with a few papillae. Their minute size, combined with the dense hair covering on most segments, makes it very difficult to observe the sensory spots in SEM, and often they are more easily observed in LM. Glandular cell outlets
type
1 only observed in lateroventral positions. Dorsal and lateral sides have scattered cuticular hairs, whereas the ventral side is nearly devoid of hairs (
Fig. 20
D–E). The posterior segment margin is nearly straight, terminating in a pectinate fringe with long and flexible fringe tips.
Table 13.
Summary of nature and location of sensory spots, glandular cell outlets, tubes and spines arranged by series in
Echinoderes lupherorum
sp. nov.
Abbreviations: LA = lateral accessory; LD = laterodorsal; LV = lateroventral; MD = middorsal; ML = midlateral; PD = paradorsal; PV = paraventral; SD = subdorsal; SL = sublateral; VL = ventrolateral; VM = ventromedial; ac = acicular spine; gco1/2 = glandular cell outlet type 1/2; ltas = lateral terminal accessory spine; lts = lateral terminal spine; pa = papilla; pe = penile spines; si = sieve plate; ss = sensory spot; tu = tube; (♀) = female and (♂) = male conditions of sexually dimorphic characters. * = indicates that the structure is not present in all specimens.
Position
|
Segment MD
|
PD
|
SD
|
LD ML
|
SL
|
LA
|
LV
|
VL
|
VM
|
PV
|
1 |
ss |
ss |
gco1 |
2 |
ss |
gco2, ss |
ss |
tu |
ss |
3 |
ss |
ss |
gco1 |
4 |
ac |
ss, gco1 |
5 |
ac |
ss |
ss |
tu |
gco1 |
6 |
ac |
ss |
ss |
ac |
ss, gco1 |
7 |
ac |
ss |
ss |
ac |
pa(♀) |
ss(♂), gco1 |
8 |
ac |
ss |
gco1, ss* |
gco2, ss |
ac |
pa(♀), gco1 |
9 |
ss |
gco1, ss |
gco2, ss |
si |
ac |
ss |
gco1 |
10 gco1, gco1 |
ss |
tu |
ss |
gco1 |
11 |
ss |
3 x pe(♂) |
ltas(♀) |
lts |
Segment 2 consists of a complete cuticular ring. The pachycyclus of the anterior segment margin is relatively thin and not interrupted. Very minute glandular cell outlets
type
2 are present in subdorsal positions (
Figs 18A
,
19B
,
20
E–F), and well-developed tubes in lateroventral positions (
Figs 18B
,
19C
,
20D
). Sensory spots are located in middorsal (
Fig. 20
E–F), subdorsal, laterodorsal (
Fig. 19B
) and ventromedial positions. Glandular cell outlets
type
1 are not observed. A secondary pectinate fringe is present near the anterior segment margin of this and the following segments, but it is usually covered by the preceding segment. On this and the following eight segments, the cuticular hairs are bracteate and densely cover the dorsal and lateral areas. The posterior segment margin is as on the preceding segment.
Segment 3, and the remaining segments, consist of one tergal and two sternal plates (
Figs 18B
,
19A, C, E, G
). The pachycyclus of the anterior segment margin is well-developed and interrupted at the tergosternal junctions and middorsally. Sensory spots are present in subdorsal (
Fig. 19D
) and sublateral positions, as well as glandular cell outlets
type
1 in
ventromedial positions. Cuticular hairs densely cover the tergal plate and the lateral halves of the sternal plates. The posterior segment margin is nearly straight, with fringe tips as on the preceding segment.
Segment 4 with a middorsal acicular spine (
Figs 18A
,
19D
). There are sensory spots and glandular cell outlets
type
1 present in ventromedial positions (
Fig. 19E
). Pachycycli, pectinate fringe of posterior margin and cuticular hairs as on preceding segment.
Segment 5 with a middorsal acicular spine and well-developed tubes in lateroventral positions (
Figs 18
A–B, 19D–E); tubes have weakly developed, yet visible bases and lateral wings. Sensory spots are present in subdorsal (
Fig. 19D
) and midlateral positions. Cuticular hairs, glandular cell outlets
type
1, pachycycli and pectinate fringe of posterior margin as on preceding segment.
Segment 6 with acicular spines in middorsal and lateroventral positions (
Figs 18
A–B, 19D–E). Sensory spots present in paradorsal (
Fig. 19D
), midlateral and ventromedial positions. Glandular cell outlets
type
1, pachycycli, pectinate fringe of posterior margin and cuticular hairs as on preceding segment.
Segment 7 with acicular spines in middorsal and lateroventral positions (
Figs 18
A–B, 19F–G). Sensory spots present in paradorsal and midlateral positions, and males in addition with sensory spots in ventromedial positions. Females with papillary structures in ventrolateral positions (
Figs 18B
,
19G
); the structures are quite prominent in LM (
Fig. 19G
), but hardly visible in SEM. Glandular cell outlets
type
1, pachycycli, pectinate fringe of posterior margin and cuticular hairs as on preceding segment.
Segment 8 with acicular spines in middorsal and lateroventral positions (
Figs 18
A–B, 19F–G). Very minute glandular cell outlets
type
2 present in laterodorsal positions (
Figs 18A
,
19F
,
20
G–H). Sensory spots present in paradorsal (
Fig. 20G
), subdorsal (
Fig. 19F
) and laterodorsal (
Fig. 20
G–H) positions (one specimen without subdorsal sensory spots though (
Fig. 20G
), and one too dirty to confirm their presence). Female specimens with papillary structures in ventromedial positions (
Figs 18B
,
19G
). Glandular cell outlets
type
1 present in subdorsal (
Fig. 19F
) and ventromedial positions. Pachycycli, pectinate fringe of posterior margin and cuticular hairs as on preceding segment.
Segment 9 with acicular spines in lateroventral positions (
Figs 18B
). Very minute glandular cell outlets
type
2 present in laterodorsal positions (
Figs 18A
,
19F
,
20I
). Sensory spots present in paradorsal (
Fig. 19F
), subdorsal (
Fig. 19F
), laterodorsal (
Fig. 20I
) and ventrolateral positions. Small rounded sieve plates are present in lateral accessory positions (
Fig. 18B
). Glandular cell outlets
type
1 are present in subdorsal and ventromedial positions. Cuticular hair covering on tergal plate is less dense than on the preceding segments, and the subdorsal to middorsal areas have no hair at all. Pachycycli and pectinate fringe of posterior margin as on preceding segment.
Segment 10 with tubes in midlateral positions (
Figs 18
,
19H, J
,
20
I–J); tubes appear fairly stout and are usually much easier to observe in LM (
Fig. 19H
) than tubes on segment
10 in
other species of
Echinoderes
; differentiated bases and lateral wings apparently not present. Sensory spots are present in paradorsal and ventrolateral positions. Glandular cell outlets
type
1 are present as two middorsal ones and a pair in paraventral positions. Cuticular hairs are scattered over the tergal plate and lateral parts of the sternal plates, but not as densely as on preceding segments. The posterior segment margin of the tergal plate is straight, whereas the margins of the sternal plates are broadly concave. Pachycycli as on preceding segment.
Segment 11 with long lateral terminal spines (
Fig. 18C
). Males with three pairs of penile spines (
Figs 18
D–E, 19J); dorsal and ventral penile spines are thin, and quite long flexible tubes, whereas the median one is thick, conical, and stout. Females with lateral terminal accessory spines (
Figs 18
A– B, 19H). Sensory spots present in subdorsal positions. The segment is completely devoid of cuticular hairs, besides the short hair-like extensions in the mid- to subdorsal areas. Tergal extensions are long and slender, extending into long but yet delicate spinous tips (
Figs 18
,
19
H–I, 20J); tergal extensions measure
24 to 28 µm
, equal to 6 to 8% of trunk length. Sternal extensions shorter and rounded.
Remarks
Due to their close resemblance, diagnostic remarks for
E. lupherorum
sp. nov.
will follow below together with remarks for
E. yamasakii
sp. nov.