Deep-sea “ cephalaspidean ” heterobranchs (Gastropoda) from the tropical southwest Pacific
Author
Valdés, Ángel
John T. Huber
text
Mémoires du Muséum national d'Histoire naturelle
2008
196
587
792
journal article
978-2-85653-614-8
1243-4442
Roxania smithae
n. sp.
Figs 53C, 54
TYPE MATERIAL
. —
Holotype
MNHN
20378 and
20 paratypes
MNHN
20379-20382,
8 paratypes
LACM 2994
.
TYPE
LOCALITY
. —
Eua
,
Tonga
,
21°12’S
,
174°56’W
,
970-983 m
[
BORDAU 2
: stn
DW 1531
]
.
MATERIAL
EXAMINED. —
Coral Sea
. MUSORSTOM 5: stn 357,
20°37’S
,
166°58’E
,
538 m
, 1 dd. —
BIOCAL:stn
DW 104
,
21°31’S
,
Chesterfield Islands
,
19°37’S
,
158°46’E
,
630 m
, 1 dd; stn 380,
166°21’E
,
375-450 m
, 1 dd
.
19°38’S
,
158°44’E
,
555-570 m
, 1 dd.
Vanuatu
. MUSORSTOM 8: stn
DW
1113,
14°53’S
,
167°06’E
,
North of
New Caledonia
. MUSORSTOM 4: stn DC
168, 700-736 m
, 3 dd,
paratypes
(
MNHN
20380).
18°48’S
,
163°11’E
,
720 m
, 1 dd; stn
CC 174
,
19°00’S
,
163°18’E
,
Fiji
.
BORDAU 1
: stn
DW 1486
,
19°01’S
,
178°26’W
,
395-540 m
,
365 m
, 1 dd
. —
BATHUS 4
: stn
DW 914
, Grand Passage,
18°49’S
, 2 dd; stn
DW 1488
,
19°01’S
,
178°25’W
,
500-516 m
, 7 dd
.
163°15’E
,
600-616 m
, 11 dd; stn
DW 917
,
18°47’S
,
163°14’E
,
Wallis and Futuna
. MUSORSTOM 7: stn
DW 507
, Futuna Is-
397-400 m
, 6 dd; stn
DW 923
,
18°52’S
,
163°24’E
,
470-502 m
, land,
14°20’S
,
178°07’W
,
419-425 m
, 1 dd; stn
DW 601
,
Wallis
1 dd.
Island
,
13°19’S
,
176°17’W
,
350 m
, 2 dd; stn
DW 604
,
13°21’S
,
New Caledonia
proper
. BIOCAL:stn
DW 77
,
22°15’S
,
167°15’E
,
176°08’W
,
415-420 m
, 3 dd,
paratypes
(
MNHN 20381
); stn
DW
440 m
, 11 dd,
paratypes
(
MNHN 20379
)
. —
BATHUS 2
: stn CP 608,
13°22’S
,
176°08’W
,
440-458 m
, 1 dd; stn
DW 635
, SW 743,
Passe
de Boulari
,
22°36’S
,
166°26’E
,
713-950 m
, 3 dd; stn
Pacific
,
13°49’S
,
179°56’W
,
700-715 m
, 1 dd
.
CP 755,
Passe
deDumbéa,
22°22’S
,
166°14’E
,
495 m
, 1 dd; stn
Tonga
.
BORDAU 2
: stn
DW 1508
,
Tongatapu
,
21°02’S
,
175°19’W
, CP 760,
22°19’S
,
166°11’E
,
455 m
, 2 dd; stn CP 761,
22°19’S
,
555-581 m
, 1 dd; stn
DW 1531
,
Eua
,
21°12’S
,
174°56’W
, 970-
166°11’E
,
490-500 m
, 1 dd
. —
BATHUS 3
: stn
DW 838
,
23°01’S
,
983 m
, 1 dd,
holotype
(
MNHN 20378
;
Fig.
53C); stn
DW 1538
,
166°56’E
,
400-402 m
, 2 dd.
21°39’S
,
175°19’W
,
471-508 m
, 1 dd; stn
DW 1547
, SW of Ton-
Norfolk Ridge
.
BIOCAL: stn
DW 56
,
23°35’S
,
167°12’E
, 695- gatapu,
21°24’S
,
175°18’W
,
488-491 m
, 1 dd; stn
DW 1548
, S of
705 m
, 1 dd.
Nomuka Islands
,
20°38’S
,
175°03’W
,
476-478 m
, 2 dd; stn
DW
Loyalty Ridge
.
MUSORSTOM 6: stn
DW 459
,
21°01’S
,
167°31’E
, 1549,
20°38’S
,
175°00’W
,
500 m
, 1 dd; stn
DW 1552
,
20°38’S
,
425 m
, 8 dd,
paratypes
(
LACM 2994
); stn
DW 468
,
21°06’S
,
174°58’W
,
491-500 m
, 3 dd,
paratypes
(
MNHN 20382
); stn
DW
167°33’E
,
600 m
, 3 dd
. —
BIOGEOCAL: stn CP 232,
21°34’S
, 1553,
20°42’S
,
174°54’W
,
650-676 m
, 1 dd; stn
DW 1585
,
Vava‘u
166°27’E
,
760-790 m
, 1 dd; stn
DW 289
,
20°36’S
,
167°00’E
,
Islands
,
18°33’S
,
173°57’W
,
578 m
, 3 dd; stn
DW 1588
,
18°40’S
,
830-840 m
, 1 dd
. —
CALSUB: pl 15, between
Lifou
and
Uvea
,
173°52’W
,
630-710 m
, 2 dd
.
DISTRIBUTION. — Collected in the Coral Sea,
Fiji
,
New Caledonia
,
Tonga
,
Vanuatu
and
Wallis and Futuna
(Fig. 54),
in
350-
975 m
.
DESCRIPTION. —
Shell morphology
. Length
7 mm
, width
5 mm
(single specimen examined). Shell solid, short, oval, with convex sides (Fig. 53C). Only 1 whorl visible, forming the entire shell. The protoconch is embedded within the outer whorl in larger specimens (more than 3.0-3.5 mm long) but is visible in juveniles (less than 3.0-3.5 mm long). Apex rounded, not umbilicate. Aperture lip rising slightly over the apex. Anterior end of the shell rounded. Aperture as long as the shell, wider anteriorly and narrowing abruptly at about 1/3 of the aperture length. Columellar margin conspicuously thickened, with a small, inconspicuous callus composed of numerous tubercles in juvenile specimens (less than 3.0-3.5 mm long). Adult specimens (more than 3.0-3.5 mm long) with a wide lip on the anterior end of the aperture and no distinct callus. Sculpture of several punctuated spiral grooves, more densely concentrated towards the posterior end. Near the apex, the punctuations are larger and more densely arranged. Colour uniform cream.
Anatomy
. Unknown. All shells collected lacked soft parts.
REMARKS. —
Roxania smithae
has intermediate features between species of
Sabatia
and
Roxania
. The shell is oval to rounded with the aperture lip rising slightly over the apex and not forming a distinct wing, as in
Roxania punctulata
(A.
Adams, 1862
)
and
R. pacifica
(Habe, 1955)
. However, the juvenile specimens have a small callus and the protoconch is not embedded within the spire, as in
Sabatia pustulosa
Dall, 1895
and
Sabatia nivea
(Watson, 1883)
. Because of the overall similarities of the adult shells of
R. smithae
to those of other species of
Roxania
it is provisionally placed in this genus, until complete specimens become available for anatomical study.
Roxania smithae
differs from
R. pacifica
in having a more oval shell with the sculpture of punctuated spiral grooves more clearly marked in the central region of the shell. In addition, juvenile specimens of
R. pacifica
do not have a callus and the protoconch is always embedded within the spire. Differences from
R. punctulata
include the absence of an umbilicus and striations on the outer lip as well as the presence of spiral grooves rather than separate punctuations in
R. smithae
.
ETYMOLOGY. — Dedicated to Nancy Smith (LACM Malacology volunteer), who provided invaluable assistance in the completion of the manuscript.