Taxonomic review of the tree snail genus Amphidromus Albers, 1850 (Pulmonata: Camaenidae) in Laos, with the description of two new species
Author
Inkhavilay, Khamla
2E620B9C-48BA-48E6-A017-FE8ED2AB0E59
Email: kinkhavilay @ gmail. com & urn: lsid: zoobank. org: author: 2 E 620 B 9 C- 48 BA- 48 E 6 - A 017 - FE 8 ED 2 AB 0 E 59
kinkhavilay@gmail.com
Author
Sutcharit, Chirasak
C2E2FA6B-A3F9-4F33-B447-B59B1BD322D4
urn: lsid: zoobank. org: author: C 2 E 2 FA 6 B-A 3 F 9 - 4 F 33 - B 447 - B 59 B 1 BD 322 D 4 & Corresponding authors: jirasak 4 @ yahoo. com; somsak. pan @ chula. ac. th
jirasak4@yahoo.com
Author
Panha, Somsak
AC935098-D901-4F35-A414-4B0D4FE44E79
urn: lsid: zoobank. org: author: AC 935098 - D 901 - 4 F 35 - A 414 - 4 B 0 D 4 FE 44 E 79 & Corresponding authors: jirasak 4 @ yahoo. com; somsak. pan @ chula. ac. th
jirasak4@yahoo.com
text
European Journal of Taxonomy
2017
2017-06-13
330
1
40
journal article
22089
10.5852/ejt.2017.330
14d5ad89-9e69-45f8-bc61-e14ca9deafbd
2118-9773
3829744
FDFA7FAC-FC92-404B-9058-A426DAB6C693
Amphidromus
(
Syndromus
)
areolatus
(Pfeiffer, 1861)
Figs 1
,
7
G−I, 9A, 10A−C, 11A–B;
Table 1
Bulimus areolatus
Pfeiffer, 1861a: 194
.
Type
locality:
Siam
[
Thailand
].
Pfeiffer 1861b: 172
, pl. 46, figs 11–12.
Amphidromus areolatus
–
Fulton 1896: 81
. —
Pilsbry 1900: 198–199
, pl. 63, figs 85–86. —
Laidlaw & Solem
1961
: 564
. —
Solem 1965: 624–625
, pl. 1, figs 4–7. —
Sutcharit
et al
. 2015: 58
, fig. 3j–k.
Material examined
Type
material
THAILAND
:
Lectotype
NHMUK
19601430 (
Sutcharit
et al
. 2015
: fig. 3j);
paralectotype
NHMUK
19601431 (1 shell).
Other material
LAOS
: 20 shells (
Fig. 10
A−C,
CUMZ
7022),
17 specimens
in freezer (
Figs 7
G−I, 9
A
, 11A–B,
CUMZ
7023), Thad Fek, Sammakeexay District,
Attapeu
; 8 shells, Thad Phasoam, Paksong District,
Champasak
(
CUMZ
7024).
Description
Shell sinistral, elongate conical, rather small, thin and glossy. Spire conical; apex acute, with black spot on tip. Whorls 5 to 6 slightly convex; suture depressed; last whorl rounded. Periostracum transparent to thin corneous. Last whorl process, with yellow to absent Band 1; Bands 2 to 4 (sometimes Bands 2 to 5) usually merge and become brownish slanted blotches with flame shape; Band 6 yellowish or roseate. Parietal callus thin and transparent. Aperture auriform; peristome expanded to weakly expanded; lip white to transparent. Columella straight and white. Umbilicus narrowly opened.
Radula
Teeth arranged in V-shaped rows, each row contains about 126 (62-(13-9)-1-(9-13)-63) teeth. Central tooth tricuspid, with triangular shaped mesocone, ectocones very small, with pointed cusp. Lateral teeth bicuspid, endocone small, with curved cusp; ectocone large, with truncate or curved cusps, gradually transformed to tricuspid marginal teeth. Tricuspid marginal teeth start around tooth number 9 to 13 outwards; endocone curve shaped; mesocone of largest size, with long and obtuse cusp; ectocone smallest, with pointed cusp. Outermost teeth with small serrated endocone and extocone; mesocone large, with curved cusps (
Fig. 7
G–I).
Genital organs
Atrium (at) rather long (n = 10). Penis (p) long, cylindrical and enlarged. Epiphallus (e) short, of about same length as penis; flagellum (fl) short and terminated in pointed tip. Appendix absent. Penial retractor muscle (pr) thin and relatively long. Vas deferens (vd) narrow tube connecting epiphallus and free oviduct (
Fig. 11A
).
Fig. 9.
Living snails of
Amphidromus
(
Syndromus
)
spp.
A
.
Amphidromus areolatus
(Pfeiffer, 1861)
from Thad Fek, Attapeu, Laos (CUMZ 7023).
B
.
Amphidromus flavus
(Pfeiffer, 1861)
from Ban Na Deauy, Luang Phrabang, Laos (CUMZ 7027).
C–D
.
Amphidromus xiengensis
Morlet, 1891
from Thad Kacham, Luang Phrabang, Laos (CUMZ 7035), the typical form, and var. “
multifasciata
”
Fulton, 1896
, respectively.
E–F
.
Amphidromus fuscolabris
Möllendorff, 1898
from Ban Phone, Sekong, Laos (CUMZ 7041–7042).
E
. Typical color form.
F
. Monochrome yellowish color form.
Internal penial wall nearly smooth and corrugated into thin penial pilasters, which form fringe around penial verge. Penial verge rather small, conical, with smooth surface (
Fig. 11B
).
Vagina cylindrical, of about same length as penis. Gametolytic duct long, proximal to genital orifice, of larger diameter than vagina and coiled; distal to genital orifice tapering to small tube of about same length as proximal part and connected to gametolytic sac. Oviduct and albumin gland very small (
Fig. 11A
).
Fig. 10.
Shells of
Amphidromus
(
Syndromus
)
spp.
A−C
.
Amphidromus areolatus
(Pfeiffer, 1861)
from Thad Fek, Attapeu, Laos (CUMZ 7022).
D
.
Amphidromus begini
(Morlet, 1886)
, syntype from Strung- Trang, Cambodia (MNHN-IM-2000-1832).
E-G
.
Amphidromus flavus
(Pfeiffer, 1861)
from Tam Pou Kham, Vientiane, Laos (CUMZ 7029).
H
.
Amphidromus flavus
var. “
indistinctus
”
Pilsbry, 1900
, holotype (ANSP 31486).
I–K
.
Amphidromus flavus
var. “
tryoni
”
Pilsbry, 1900
.
I
. Lectotype (ANSP 31488).
J
. Paralectotype (ANSP 252745).
K
. Specimen from Ban Na Deauy, Luang Phrabang, Laos (CUMZ 7026).
L–M
.
Amphidromus semitessellatus
(
Morlet, 1884
)
.
L
. Lectotype (MNHN-IM-2000-1985).
M
. Specimen from Cambodia (NHMUK).
Fig. 11.
Genitalia of
Amphidromus
(
Syndromus
)
spp.
A–B
.
Amphidromus areolatus
(Pfeiffer, 1861)
from Thad Fek, Attapeu, Laos showing the reproductive system and interior structures of the penis and vaginal chamber (CUMZ 7023).
C–D
.
Amphidromus flavus
(Pfeiffer, 1861)
from Ban Na Deauy, Luang Phrabang, Laos showing the general characteristics of the genital system and the interior structures of the penis, atrium and vagina chamber (CUMZ 7027).
Internal wall of vagina shows longitudinal vaginal pilasters (vp); proximal to genital orifice with nearly smooth surface for about half of its length, distally pilasters become corrugated ridges (
Fig. 11B
).
Distribution
The species is known from southern
Laos
, where the specimens were collected at Thad Fek, Sammakeexay District, Attapue and Thad Phasoam, Paksong District,
Champasak
in a dry dipterocarp forest.
Remarks
This species can be distinguished from
A. zebrinus
(Pfeiffer, 1861)
and
A. begini
(Morlet, 1886)
by its having a smooth shell surface and brownish spiral Bands 4 and 5 present, with white lip. In contrast,
A. zebrinus
(see
Sutcharit
et al
. 2015
: fig. 15k) has an elongate conical shell shape, Band 1 absent, Bands 2 to 5 merged and developing slanted radial streaks, as well as a reddish band between Bands 5 and 6.
Amphidromus begini
exhibits strong radial ridges, Bands 2 to 6 merged and developing slanted brownish radial streaks, and brownish ribs (
Fig. 10D
,
syntype
MNHN-IM-2000-1832).