Taxonomy and anatomy of Amphiboloidea (Gastropoda: Heterobranchia: Archaeopulmonata)
Author
Golding, Rosemary E.
Author
Ponder, Winston F.
Author
Byrne, Maria
text
Zootaxa
2007
1476
1
50
journal article
10.5281/zenodo.176773
1a670eb6-5f50-42d6-ace0-3e52fd4f4c17
1175-5326
176773
Naranjia
cf.
swatowensis
(
Yen, 1939
)
Salinator swatowensis
Yen, 1939
: 65
, pl. V.
Salinator fragilis
(not of Lamarck, 1788)
Tong 1986
: 444
, pl. III, figs. D, E.
Type
material
:
Holotype
:
China
, Swatow: Kwangtung (now Guangdong). Location of
type
material unknown, not examined.
Other material examined
:
China
,
Hong Kong
New Territory: Tsim Bei Tsui, mangrove soil surface,
10 Apr 1986
, L. Tong (AMS C.153259); Tsim Bei Tsui, in mangroves,
15 Apr 1992
, W.F. Ponder (AMS C.446511).
Redescription
: Shell (
Fig. 2
M): Fragile, spire short, diameter to
7 mm
, exterior smooth with faint striae. Last whorl relatively large, spiral line or ridge on shoulder of lower whorls present in some specimens. Exterior brownish-orange, transparent when empty.
Operculum: Corneous, thin, pale yellow, with paucispiral nucleus. Internal surface of operculum lacking elaborations around nucleus.
External morphology: Head-foot white or pale grey in formalin-preserved specimens, lacking pigmentation patterns.
Mantle organs (
Fig. 7
D): As for
S. fragilis
, with following differences. Opposed ciliary tracts short, restricted to exhalant canal. Hypobranchial gland oval, yellow in formalin-preserved specimens, with large chambers with non-staining contents, presumably mucus.
Digestive system: As for
A. crenata
, but proportionally smaller.
Radula (
Figs. 10
G, H): Central teeth with 13–17 cusps, mesocone enlarged; other cusps on central tooth arranged in undulating pattern forming ‘butterfly’ shaped profile. Single pair of lateral teeth on each row of radula; inner two cusps on lateral teeth separated by deep, u-shaped groove, outer cusp on lateral tooth narrow and reduced. Marginal teeth unicuspid, narrow, elongate, approximately 25 teeth on each side of radula.
Central nervous system (
Fig. 12
E): As for
S. fragilis
, with following differences. Cerebral-pleural ganglia twice as large as pedal ganglia; cerebral commissure long, thick. Visceral loop moderately long, right parietalvisceral connective shorter than left. Presence of parapedal and subcerebral commissures not confirmed.
Reproductive system (
Fig. 14
G): Proximal reproductive system as for
S. fragilis
, distal structures differ as follows. Distal spermovipositor fused to spermovipositor sheath forming narrow ridge, folded across aperture of spermoviduct proximally, exterior surface bearing rows of long, unchitinised papillae. Spermovipositor sheath highly folded, relatively thin-walled. Enlarged vaginal pocket (‘accessory bursa’) opening into spermovipositor sheath lumen on left of genital aperture, folded behind spermovipositor. Globular spermatophore present in enlarged vaginal pocket of some animals. Egg mass unknown.
Distribution and habitat
(
Fig. 1
): The
type
material of
N.
cf.
swatowensis
was described from Guangdong on the southern coast of
China
. The material on which the genus name is based is from mangrove habitat in
Hong Kong
.
Remarks:
Our material is similar to Yen’s (1939) description and figure of
S. swatowensis
. However, Yen’s (1939) description is based only on shell characters which are relatively uninformative in distinguishing amphibolid taxa. Thus our identification of the
Hong Kong
material as
N.
cf.
swatowensis
is tentative, especially as
Hong Kong
is a considerable distance southwest of the
type
locality.
Tong (1986)
figured shells of this species from
Hong Kong
as ‘
S. fragilis
’ (a misidentification) and a second unnamed
Salinator
species with a spiral ridge on the shell. Anatomical examination of her specimens has failed to reveal any differences between these ‘species’ apart from the presence of a spiral ridge, which is here interpreted as intraspecific variation as there are also intermediate forms with a weak spiral line. It is probably impossible to confirm the identity of the material without anatomical examination of topotypic material of
S. swatowensis
. It is possible that our
Hong Kong
specimens represent another new taxon, or they may even prove to be
Salinator sanchezi
subsp. s
purca
Yen, 1939
(see
Incertae sedis
section) from Hainan on the southern coast of
China
. Despite confusion with species identity, the material examined in this study demonstrates a clear anatomical separation from
Salinator
based on the colour of the shell, shape of the central radular teeth and the unusual spermovipositor bearing finger-like papillae.