Turbo-taxonomy: 21 new species of Myzostomida (Annelida)
Author
Summers, Mindi M.
Author
Al-Hakim, Iin Inayat
Author
Rouse, Greg W.
text
Zootaxa
2014
3873
4
301
344
journal article
42367
10.11646/zootaxa.3873.4.1
fb49ba3b-9228-4653-bad8-a22bf4828785
1175-5326
252208
84F8465A-595F-4C16-841E-1A345DF67AC8
Asteromyzostomum grygieri
n. sp.
Summers & Rouse
Fig. 1
Asteromyzostomum
sp.—
Grygier (1988)
;
Grygier (2000)
;
Lanterbecq
et al.
(2006)
Holotype
:
SIO-BIC A3801 (S6950)
hologenophore
(1 spm: 95% ethanol). Elephant
Island
,
Antarctica
(Stn. E1- 82) (
61°09.0527’S
,
54°11.8609’W
),
222–
247 m
. Collected via the R/V
Nathaniel B. Palmer
using a Blake trawl on
22 October 2011
by Nerida Wilson, GWR, MMS, and science team. Genbank (COI—KM014170).
Host.
Labidiaster annulatus
Sladen
(
Heliasteridae
,
Forcipulatida
. Asteroidea).
FIGURE 1.
Live photographs of
Asteromyzostomum grygieri
n. sp.
(A, B) Holotype (SIO-BIC A3801) and other non-types on host
Labidiaster annulatus
,
arrowheads indicate myzostomids. (C, D) Paratype (SIO-BIC A3554) ventral, mouth pierced through body wall (C) and dissected (D), arrow shows mouth and ring of circumoral tentacles. (E) Paratype (SIO-BIC A3232) ventral, five parapodia visible to left of mouth, indicated with roman numerals. (F) Two juveniles (non-types), ventral, showing five pairs of parapodia to left and right of mouth; one side indicated with roman numerals, the third pair offset from the others. Scalebars 1 cm (A); 1 mm (C–F).
Paratypes
:
SIO-BIC A3232 (S4392)
syngenophores
(2 spms: in 70% ethanol after formalin fixation). Elephant
Island
,
Antarctica
(Stn. EI-79) (
61°10.4189’S
,
54°11.9508’W
),
223–
242 m
. Collected via the R/V
Nathaniel B. Palmer
using a Blake trawl on
22 October 2011
by Nerida Wilson, GWR, MMS, and science team. Host:
Labidiaster annulatus
.
SIO-BIC A3836 (S6947)
syngenophore
(1 spm: 95% ethanol). Elephant
Island
,
Antarctica
(Stn. EI-79) (
61°10.4189’S
,
54°11.9508’W
),
223–
242 m
. Collected via the R/V
Nathaniel B. Palmer
using a Blake trawl on
22 October 2011
by Nerida Wilson, GWR, MMS, and science team. Host:
Labidiaster annulatus
.
SIO-BIC A3554 (
S20195
)
syngenophores
(2 spm: 1—in 70% ethanol after formalin fixation; 1—95% ethanol).
South Georgia
,
Antarctica
(Stn. SG4-5) (
53° 42' 54.4"S
,
36° 50' 8.5"W
),
190 m
.
Collected via the R/V
Nathaniel B. Palmer
using a Blake trawl on
16 April 2013
by Nerida Wilson, GWR, and science team. Host:
Labidiaster annulatus
,
SIO-BIC E6160 (
S20209
).
Etymology.
Named for Mark Grygier, who first discovered this species. We also name this species to acknowledge his significant contributions to myzostomid taxonomy.
Diagnosis and description.
Specimens recovered on sides of arms and in ambulacral groove, mouth piercing through body wall of host (
Fig. 1
A–C).
Holotype
body wider than long, approximately
6 mm
long and
8 mm
wide following fixation. Posterior margin composed of convoluted, lobular folds. Body margin acirrate. Five pairs of parapodia on ventral side on either side of mouth, third pair farther from the edge (
Fig. 1
E–F). Mouth surrounded by ring of circumoral tentacles (
Fig. 1
D). Color peach in life, faded in preservative.
Remarks.
Asteromyzostomum
comprises three other species—
Asteromyzostomum arcticum
Wagin, 1954
,
A. multiplicatum
Wagin, 1954
,
A. witjasi
Wagin, 1954
—all described from seastars in Arctic waters (
Table 1
). Specimens most likely to be
Asteromyzostomum grygieri
n. sp.
were previously recorded, but not described, from
Labidiaster
sp. outside of McMurdo Sound,
Antarctica
(
Grygier 2000
)
. These specimens were catalogued at the Smithsonian (NMNH). One of these specimens (NMHN 98554 or 98555) was sequenced in
Lanterbecq
et al.
(2006)
, but this sequence has been shown to be incorrect in
Summers & Rouse (2014)
.
Asteromyzostomum grygieri
n. sp.
is the first myzostomid described from a seastar in
Antarctica
. All
Asteromyzostomum
species insert their mouth through the integument of the host, and are found attached to the sides of the arms or in the ambulacral grooves of the host (
Wagin 1954
;
Grygier 2000
). An additional specimen has been reported from Atlantic waters, though it was found disassociated from its host and has not been described (
Wagin 1954
;
Grygier 1988
).