A review of the Diapheridae (Gastropoda: Eupulmonata: Streptaxoidea), with special emphasis on India and Myanmar
Author
Páll-Gergely, Barna
Author
Hunyadi, András
Author
Grego, Jozef
Author
Sajan, Sheikh
Author
Tripathy, Basudev
Author
Chen, Zhe-Yu
text
Raffles Bulletin of Zoology
2020
2020-08-06
68
682
718
journal article
10.26107/RBZ-2020-0083
2345-7600
5349761
83A57E5F-10AB-46EF-A35C-29B2E747851A
Rowsonia
Páll-Gergely
,
new genus
Type
species.
Ennea beddomei
W.T.
Blanford, 1881
(
Fig. 12J–Q
).
Diagnosis.
Shell small to large, smooth to regularly ribbed, slender conical. Parietal callus well-developed to weak. Basal swelling not developed. Parietal lamella elongated inside, outer end usually straight, outer portion curves towards palatal wall. Inner portion curves towards columella. Palatal wall with an upper palatal tooth that faces the curved parietal lamella. There are two to three deeply situated, elongated additional folds (upper, middle, and lower palatal folds). Columellar lamella well-developed, sharp, oblique to shell axis. See
Fig. 1O
for explanation.
RAFFLES BULLETIN OF ZOOLOGY
2020
Fig. 13.
Pupennea planguncula
(
Benson, 1863
)
, NHMUK 1875.3.6.39. Both scales represent 1 mm; scale “a” refers to fig. A, scale “b” refers to figs. B–I.
Differential diagnosis.
Rowsonia
,
new genus
, differs from
Ennea
(compared only with the
type
species) in the following characters: the shell shape of the new genus is conical, whereas it is ovoid in
Ennea
; the parietal lamella is short in
Ennea
, inner and outer portions of different orientation cannot be recognised; columellar lamella of
Ennea
is weak, low, and not visible from straight view to the aperture; the deeply situated folds are much longer than those of
Rowsonia
,
new genus
, and they correspond with grooves on the dorsal (“neck”) region.
Pupennea
,
new genus
is ovoid, possesses two teeth on the columellar side (columellar lamella and denticle), has a shorter parietal lamella, has a complex structure consisting of the upper and lower parietal teeth, and lacks deeply situated palatal folds.
Sinoennea
species
are usually elongate ovoid and cylindrical in shell shape, lack any deeply situated parietal/basal folds, usually have a prominent basal swelling and there is a depression that corresponds with the upper palatal tooth. See under
Platylennea
,
new genus
.
Included species.
Rowsonia beddomei
(W.T.
Blanford, 1881
)
,
R. canarica
(W.T.
Blanford, 1869
)
,
R. pirriei
(L.
Pfeiffer, 1855
)
,
R. sculpta
(W.T.
Blanford, 1869
)
, and
R. turricula
(W.T.
Blanford, 1899
)
.
Etymology.
This genus is dedicated to and named after Ben Rowson (National Museum of Wales), a specialist of the
Streptaxoidea
. Grammatical gender: feminine.
Distribution.
Southern
India
(
Fig. 10
).
Remarks.
The most closely related genus is probably
Platylennea
,
new genus
, which also inhabits southern
India
. The distinction of the two groups is clear, and thus, these two groups should be separated as distinct genera. However, the morphological diversity of
Sinoennea
is still larger than the difference between
Platylennea
,
new genus
and
Rowsonia
,
new genus
.