The copepod genus Hatschekia Poche, 1902 (Siphonostomatoida: Hatschekiidae) from triggerfishes (Pisces: Tetraodontiformes: Balistidae) from off the Ryukyu Islands, Japan, with descriptions of eleven new species
Author
Uyeno, Daisuke
Author
Nagasawa, Kazuya
text
Zootaxa
2010
2478
1
40
journal article
10.5281/zenodo.195334
5c776f2d-8efa-408e-855d-5688a5ca2c0e
1175-5326
195334
Hatschekia jonesi
n. sp.
(
Figs 16–29
)
Type
material.
Holotype
, female (
NSMT
–Cr 20901), ex
Sufflamen bursa
(Bloch & Schneider)
(
Tetraodontiformes
:
Balistidae
), off Cape Maeda (
26°26’N
,
127°46’E
), Okinawa-jima Island, the Ryukyu Islands, East
China
Sea,
Japan
,
2 September 2005
.
Paratypes
:
6 females
(
NSMT
–Cr 20902), ex
S
.
bursa
, off Cape Maeda (
26°26’N
,
127°46’E
), Okinawa-jima Island, the Ryukyu Islands, East
China
Sea,
Japan
,
2 September 2005
.
Other material examined.
5 females
(
RUMF
–ZC–00922), ex
S
.
fraenatum
(Latreille)
, off Chatan (
26°19’N
,
127°44’E
), Okinawa-jima Island, the Ryukyu Islands, East
China
Sea,
Japan
,
9 December 2005
.
Description of female.
Body (
Fig. 16
) 837–1034 (902 ± 61) long, excluding caudal rami (n = 12). Cephalothorax round, slightly shorter than wide [175–220 (195 ± 16) × 212–276 (236 ± 20)], with dorsal, Mshaped chitinous frame. Trunk rod-like, longer than wide [666–818 (711 ± 47) × 166–198 (182 ± 12)], widest in anterior ¼. Urosome (
Fig. 17
) excluding caudal ramus shorter than wide [34–49 (42 ± 5) × 58–80 (69 ± 7)]. Genital complex fused to abdomen without border. Caudal ramus (
Fig. 17
) slightly longer than wide [15–28 (20 ± 4) × 10–17 (13 ± 2)], bearing 5 naked setae.
Rostrum expanded anteriorly with 1 round process on each posterolateral corner (
Fig. 18
). Antennule (
Fig. 18
) indistinctly 5-segmented, 138–166 (146 ± 9) long; armature formula: 9, 5, 4, 1, 13 + 1 aesthetasc. Antenna (
Fig. 19
) 3-segmented; proximal segment (coxa) unarmed; middle segment (basis) ornamented with surface pits; terminal claw bearing 1 basal seta; proximal segment length 41–50 (39 ± 16); middle segment length 101–135 (99 ± 42); terminal claw length 25–32 (24 ± 10); total length 169–210 (162 ± 67). Parabasal papilla (
Fig. 20
) well developed, wrinkled, extending to mid-lateral level of cephalothorax and visible from dorsal side. Oral cone robust. Mandible (
Fig. 21
) slender, with 4 sharp apical teeth. Maxillule (
Fig. 22
) bilobate; both lobes armed with 2 tapering elements; 2 elements on inner lobe swollen. Maxilla (
Fig. 23
) 4- segmented; proximal segment unarmed; second segment rod-like, with 1 basal seta; third segment elongate, with 1 distal seta; terminal segment small, with 1 small seta and bifid claw. Maxilliped absent.
Legs 1 and 2 (
Figs 24–25
) biramous, with exopods composed of 2 indistinct segments and 2–segmented endopods; leg armature formula as follows:
| Protopod |
Exopod |
Endopod |
| Leg 1 |
1–1 |
1–0; 6 |
0–0; 5 |
| Leg 2 |
1–0 |
1–0; 5 |
0–0; 4 |
Leg 1 (
Fig. 24
) 87–105 (93 ± 6) long; protopod length 44–59 (50 ± 4); exopod length [39–46 (42 ± 2)] exceeding endopod length [24–36 (29 ± 3)]. Leg 2 (
Fig. 25
) length 94–114 (102 ± 7); protopod length 57–69 (64 ± 4); exopod length 35–45 (38 ± 3); endopod length 45–56 (51 ± 3). Both exopods and protopod of leg 2 ornamented with rows of blunt spinules on anterior surface. Endopod of leg 2 broad.
Intercoxal sclerites of legs 1 and 2 (
Figs 26–27
) bearing 4 processes.
Leg 3 (
Fig. 28
) represented by 2 simple setae on small conical process at anterior mid-lateral surface of trunk. Leg 4 (
Fig. 29
) represented by 1 simple lateral seta on posterior ¾ of trunk.
Variability of measurement.
Specimens used as “other materials” did not show remarkable differences in meristic characters. Measurements of body parts and appendages as follows: body length 598–874 (779 ± 105), cephalothorax length 126–199 (180 ± 31), cephalothorax width 187–224 (210 ± 41), trunk length 472– 690 (603 ± 80), trunk width 125–227 (199 ± 42), abdomen length 28–46 (38 ± 7), abdomen width 49–74 (65 ± 10), caudal ramus length 17–23 (20 ± 3), caudal ramus width 9–13 (12 ± 2), antennule length 110–160 (141 ± 20), antenna proximal segment length 28–44 (39± 7), antenna middle segment length 57–92 (80 ± 16), antenna terminal segment length 18–35 (26 ± 6), antenna total length 103–163 (145 ± 25), leg 1 length 58–84 (76 ± 11), leg 1 protopod length 34–52 (44 ± 8), leg 1 exopod length 24–38 (33 ± 5), leg 1 endopod length 18– 29 (26 ± 4), leg 2 length 58–92 (80 ± 14), leg 2 protopod length 37–60 (53 ± 9), leg 2 exopod length 21–32 (27 ± 5), leg 2 endopod length 23–38 (31 ± 6).
FIGURES 16–23.
Hatschekia jonesi
n. sp.
, female, holotype NSMT–Cr 20901. 16, habitus dorsal; 17, posterior part of trunk, dorsal; 18, antennule, ventral, rp = rostrum process (drawn from a paratype, NSMT–Cr 20902); 19, antenna, ventral. (drawn from a paratype, NSMT–Cr 20902); 20, antenna with parabasal papilla (drawn from a paratype, NSMT– Cr 20902); 21, mandible (drawn from a paratype, NSMT–Cr 20902); 22, maxillule; 23, maxilla. Scale bars: 16, 200μm; 17–19, 23, 40μm; 20, 22, 20μm; 21, 10μm.
FIGURES 24–29.
Hatschekia jonesi
n. sp.
, female, holotype NSMT–Cr 20901. 24, leg 1, anterior view; 25, leg 2, anterior view; 26, intercoxal sclerite of leg 1, anterior view; 27, intercoxal sclerite of leg 2, anterior view; 28, leg 3, ventral; 29, leg 4, ventral. Scale bars: 24–27, 30μm; 28–29, 10μm.
Attachment site.
Gill filaments.
Remarks.
Hatschekia jonesi
n. sp.
also has 4 processes on the intercoxal sclerites of legs 1 and 2. These processes are shared with 10 species (see remarks for
H
.
hemicyclium
) and one new species, namely
H
.
hemicyclium
n. sp.
Hatschekia jonesi
n. sp.
is distinguishable from 7 species (
H
.
balistae
,
H
.
bibullae
,
H
.
cylindrus
,
H. khahajya
,
H
.
kuroshioensis
,
H
.
monacanthi
and
H
.
pseudostracii
) by having leg 3 located on a small conical process. Even though the base of leg 3 was not described for
H
.
balistae
it can be separated from the new species by the presence of an apex on the cephalothorax.
Hatschekia hemicyclium
n. sp.
differs from the new species as follows: leg 2 with the exopod longer than the endopod, a considerably higher leg 2 exopod length/endopod length ratio [1.39 ± 0.16 vs. 0.80 ± 0.08 (U-test;
p
<0.001),
Table 1
], a smaller parabasal papilla, leg 3 represented by setae on a small papilla, and leg 2 with a broad endopod.
Hatschekia lima
is distinguishable from the new species by having 4 setae on the distal tip of the endopod of leg 1 and the maxillule with a highly sclerotized inner lobe while
H
.
sunaoi
is differentiated from the new species by having a distinctly higher antenna length/body length ratio [0.40 ± 0.03, vs. 0.18 ± 0.06 (U-test;
p
<0.001),
Table 1
, see also table
1 in
Uyeno & Nagasawa 2009b
] and by not having a well-developed parabasal papilla (
Uyeno & Nagasawa 2009b
).
Etymology.
The specific name of the new species,
jonesi
, honors Dr. J. B. Jones who has greatly contributed to the taxonomy of the genus
Hatschekia
.