Dactylogyrids (Monogenoidea) parasitizing the gills of spinefoots (Teleostei, Siganidae): revision of Tetrancistrum Goto and Kikuchi, 1917, with descriptions of two new species from Siganus spp. of the Red Sea and Celebes
Author
Kritsky, Delane C.
Author
Galli, Paolo
Author
Tingbao, Yang
text
Journal of Natural History
2007
2010-12-02
41
25 - 28
1513
1551
http://dx.doi.org/10.1080/00222930701452989
journal article
10.1080/00222930701452989
1464-5262
4581968
Tetrancistrum suezicum
(Paperna, 1972)
comb. n.
(
Figures 28–34
)
Synonyms
:
Pseudohaliotrematoides polymorphus suezicus
Paperna, 1972
;
P. suezicus
Paperna,
1972;
Pseudohaliotrematodides polymorphus
suezicus
of
Ktari and Ktari (1974)
(
lapsus
);
Pseudohaliotrematoides suezicus
Paperna, 1972
.
Figures 28–34.
Tetrancistrum suezicum
(Paperna, 1972)
comb. n.
from the marbled spinefoot,
Siganus
riυulatus
, Ras Mohammed National Park, Egypt. (28) Whole mount (composite, ventral view). (29) Copulatory complex (dorsal view). (30) Ventral bar. (31) Dorsal bar. (32) Dorsal anchor. (33) FH loop of hook. (34) Ventral anchor. Scale bar: 400 Mm (28); 30 Mm (29–34).
Redescription.
Based on six voucher specimens from
S. riυulatus
in the Ras Mohammed National Park. Body foliiform; trunk broad; cephalic region narrow; peduncle tapered posteriorly; greatest body width near body midlength. Cephalic lobes moderately to well developed; each head organ comprises several groupings of terminations of cephalic-gland ducts; large bilateral groups of cephalic glands posterolateral to pharynx. Two pairs of eyespots in two of six specimens; posterior pair larger and slightly farther apart than anterior pair; random accumulations of chromatic granules present or absent; minute subovate granules scattered throughout cephalic region. Pharynx ovate; intestinal caeca lacking diverticula. Testis subspherical; vas deferens and seminal vesicle not observed; prostatic reservoirs inconspicuous. Copulatory complex comprises articulated MCO and accessory piece. MCO a J-shaped tube with short anterior flange and elongate posterior flange terminally frayed; accessory piece rod-shaped, with doubly recurved tip. Germarium comparatively large, conical to subcylindrical; ootype receives vaginal duct and bilateral vitelline ducts; uterus midventral, extends ventrally to genital pore along body midline. Vaginal pore at level of copulatory complex; vaginal vestibule variable, lightly sclerotized; meandering vaginal duct extending to ootype. Vitellarium dense. Haptoral hooks absent; few FH loops occasionally retained in adult. Ventral and dorsal anchors typical; superficial root of ventral anchor noticeably longer than deep root. Ventral bar straight, with ends recurved posteriorly to posterior margin of bar; dorsal bar broadly V-shaped, with slight terminal expansions.
Measurements.
Body 1306 (
n
51) long; greatest width 330 (301–359;
n
52). Haptor 85 (
n
51) long, 72 (
n
51) wide. Pharynx 55 (47–64;
n
52) wide. Copulatory complex 87 (77– 100;
n
55) long. Ventral anchor 80 (70–84;
n
54) long; base 34 (32–36;
n
53) wide. Dorsal anchor 81 (72–89;
n
54) long; base 25 (24–27;
n
53) wide. Ventral bar 30–31 (
n
52) long; dorsal bar 22 (21–24;
n
53) long. Germarium 208 (167–249;
n
52) long, 115 (106–124;
n
52) wide; testis 179 (118–240;
n
52) long, 144 (112–176;
n
52) wide.
Source of current specimens.
Siganus
riυulatus
:
Nabq Bay
,
Ras Mohammed National Park
(
South Sinai
,
Red Sea
),
Egypt
(28
°
029520N, 34
°
269210E),
8 May 2003
,
20 October 2005
.
Type
host and locality.
Siganus
riυulatus
:
Gulf
of
Suez
near Ras abu-Rudeis,
Red Sea
.
Site of infestation.
Gills.
Specimens studied.
Six voucher specimens, USNPC 99368, 99369, BMNH 2007.1.3.43, MPM 18854, MSNM Pi 3906, 3907.
Preυious records.
Siganus
riυulatus
: Gulf of Suez near Ras abu-Rudeis, Red Sea as
Pseudohaliotrematoides polymorphus suezicus
by
Paperna (1972b)
; Gulf of
Gabès
,
Tunisia
as
Pseudohaliotrematodides polymorphus
suezicus
by
Ktari and Ktari (1974)
;
8 km
S of Eilat,
Israel
as
Pseudohaliotrematoides polymorphus suezicus
by
Diamant and Paperna (1986)
; Mediterranean coast of
Israel
as
P.
p. suezicus
by
Diamant and Paperna (1986)
; various localities in the Mediterranean Sea as
P. suezicus
Paperna, 1972
by
Diamant (1989)
; northern Gulf of Eilat,
Israel
as
P.
p. suezicus
by
Diamant et al. (1999)
.
Remarks.
This species was originally described as a subspecies of
Pseudohaliotrematoides polymorphus
by
Paperna (1972b)
. The subspecies was elevated to full specific rank by
Diamant (1989)
, but
Diamant et al. (1999)
reversed this taxonomic revision without comment when the authors referred to the species as
P. polymorphus suezicus
. The species is now re-elevated to specific rank and transferred to
Tetrancistrum
based on the morphology of its haptoral armament and internal organ systems.