Cymonomus curvirostris Sakai 1965
Author
Salazar-Vallejo, Sergio I.
text
Zoological Studies
2017
Zool. Stud.
2017-10-31
56
32
16
16
http://dx.doi.org/10.5281/zenodo.12825164
journal article
10.6620/ZS.2017.56-32
1810-522X
PMC6517758
31966231
12825856
Sternaspis lindae
sp. nov.
(
Fig. 4
)
urn:lsid:zoobank.org:act:
A157B737-7606-487E-9893- 2B6E87B2F35F
Sternaspis fossor
:
Chamberlin 1919:405-406
(
non
Stimpson, 1853
,
partim
).
Type material
:
Eastern Tropical Pacific
,
Panama
.
Holotype
(
USNM 19478
), and
five paratypes
(
USNM 1437649
),
RV Albatross
,
Gulf
of
Panama
, Sta. 3391 (
07°33'40"N
,
79°43'20"W
),
275 m
, green mud,
9 Mar. 1891
(
paratypes
one previously dissected, body
12.5-14.5 mm
long,
9.2- 10.5 mm
wide, left shield plate
3.1-3.3 mm
long, 3.0-
3.6 mm
wide).
© 2017 Academia Sinica,
Taiwan
Additional material
: Eastern Tropical Pacific.
Panama
.
One specimen
(
UMML
22-1035),
18 km
E off
Isla
Iguana, R.V. Pillsbury, Cruise 6703, Sta. 502 (
07°40'N
,
79°50.5'W
to
07°40.3'N
,
79°50.9'W
), 79-
77 m
,
2 May 1967
(introvert partially exposed, body slightly macerated,
17 mm
long,
7 mm
wide, left shield plate
2.2 mm
long,
2.4 mm
wide).
Three specimens
(
UMML
22-1038), R.V. Pillsbury, Cruise 6703, Sta. 512 (
07°31'N
,
79°42'W
),
210 m
,
4 May 1967
(introvert exposed in
two specimens
, invaginated in the other, shield with bands defined, brownish and dirty pink; body
18-25 mm
long,
10- 11 mm
wide, left shield plate
3.5-3.8 mm
long,
3.5-3.8 mm
wide).
One specimen
(
UMML
22- 1043),
3 km
SSE Taboga Island, R.V. Pillsbury, Cruise 6703, Sta. 483 (
08°40.5'N
,
79°30.7'W
to
08°39.3'N
,
79°31.7'W
),
22-27 m
,
1 May 1967
(juvenile, macerated, anal tube and gonopodial lobes eroded; body
14 mm
long,
6 mm
wide, shield left plate
1.4 mm
long,
1.6 mm
wide).
Colombia
.
One specimen
(
UMML
22- 1045), Bahía Chupica, Chocó, R.V. Gillis, Sta. 9 (
06°36.7'N
,
77°27.4'W
), mud and plant debris,
119-128 m
,
16 Jan. 1972
(introvert invaginated, shield variegated, dirty orange and pale pink; body
15 mm
long,
8 mm
wide, left shield plate
2.6 mm
long,
2.9 mm
wide).
Description
:
Holotype
(
USNM
19478) with body maculated, whitish with black spots of different size; introvert barely exposed, integument smooth (
Fig. 4A
); abdomen with fine, long papillae arranged in discontinuous single transverse series per segment. Body papillae minute, abundant, mostly short, larger in introvert. Body
12.5 mm
long,
8.5 mm
wide, about 28 segments.
Prostomium, peristomium and mouth not visible. Additional specimens (
UMML
22.1038) with prostomium hemispherical, opalescent. Peristomium rounded, projected at the mouth, with papillae covering its surface; lateral mouth areas smooth; surface behind prostomium smooth. Mouth circular, with minute papillae not extended up to first hook series.
Fig. 4.
Sternaspis lindae
sp. nov.
(A) Holotype (USNM 19478), ventral view. (B) Same, anterior end, frontal view. (C) Same, shield. (D) Same, branchial plate. (E-H) Paratypes (USNM 1437649), shields, E, F: Shields slightly cleaned by brushing off foreign particles and shield papillae, G: Another paratype, shield with left half cleaned, H: Same shield, after cleaning the right half. Scale bars: A = 1.8 mm, B = 1.2 mm, C-E = 1.3 mm, F = 1.1 mm, G, H = 1.5 mm.
© 2017 Academia Sinica,
Taiwan
Introvert exposing chaetae of chaetiger 3 and chaetae of chaetiger 2. Chaetiger 3 with 12 large, falcate thick hooks, distally broken (
Fig. 4B
) (entire, tapered, up to
20 in
UMML
22.1038); hooks from chaetiger 2 with subdistal to medial darker areas. Genital papillae short, thick, tapered (digitate or basally swollen in
UMML
22.1038), protrude ventrally from intersegmental groove between segments 7 and 8. Pre-shield region with 7 segments; capillary chaetae not seen, probably broken.
Shield reddish, paler towards the lateral and posterior margins, with ribs and concentric lines; suture visible throughout ¾ of shield, indistinct in the posterior region (
Fig. 4C
). Anterior margins rounded; anterior depression deep; anterior keels partly visible, not completely exposed. Lateral margins projected laterally, reduced posteriorly. Fan truncate, slightly projected beyond the poorly defined posterior corners, barely crenulated; median notch very shallow.
Marginal chaetal fascicles include 10 lateral ones, chaetae ovally arranged, and seven posterior ones, chaetae in a slightly curved arrangement. First two lateral fascicles emerge from dorsal edge of shield. Peg chaetae and additional thin capillaries present.
Branchiae and interbranchial filaments lost (
one paratype
with thin helicoid branchiae and thinner, straight interbranchial filaments). Branchial plate anteriorly expanded, truncate (rounded in
one paratype
), with about 16 rows of branchiae in its widest region (
Fig. 4D
).
Variation
: Shields bands are more or less defined. Anterior corners are angular to blunt, anterior keels are visible in three out of five shields. Fans are medially notched, the posterior margin is slightly crenulate to denticulate, and the posterolateral corners are slightly projected, if at all.
One juvenile
(
UMML
22-1043) shows a shield with posterior fan margin denticulate.
Etymology
: This species is after Linda Ward, good friend and colleague, because she has been very helpful and supportive of my research activities during many years. The epithet is a noun in the genitive case.
R e m a r k s
:
S t e r n a s p i s l i n d a e
sp. nov. r e s e m b l e s
S. r i e t s c h i
(
Caullery, 1944
) as redescribed elsewhere (
Sendall and Salazar-Vallejo 2013
) because both species have shields with truncate fans and poorly defined posterior corners. They differ because in
S. lindae
the fan is smooth to barely crenulated, and the lateral margins are moderately projected laterally, whereas in
S. rietschi
the fan is crenulated and the lateral margins are markedly projected laterally. Further,
S. lindae
was found in
275 m
depth in the Gulf of
Panama
, and
S. riestschi
was dredged in
1788 m
depth in
Indonesia
. The specimens herein described were identified and recorded as
Sternaspis fossor
Stimpson, 1853
but in this species the fan is more projected posteriorly and concentric lines form distinct bands.
Chamberlin (1919)
indicated
10 specimens
, but only 6 are available. On the other hand, the spotted pigmentation is apparently derived after some foreign component like ink or rubber seals stain, because it can be removed by brushing the body surface and cannot be regarded as diagnostic. The mottled pattern, if the stain has some affinity for glandular cells, would reveal their distribution including over the integument layer covering the shield. The additional specimens were not stained.
D i s t r i b u t i o n
: Gulf of
Panama
, to NW
Colombia
, in muddy bottoms,
119-275 m
water depth.