Small snails in a big place: a radiation in the semi-arid rangelands in northern Australia (Eupulmonata, Camaenidae, Nanotrachia gen. nov.)
Author
Köhler, Frank
Author
Criscione, Francesco
text
Zoological Journal of the Linnean Society
2013
Zool. J. Linn. Soc.
2013-08-29
169
1
103
123
http://dx.doi.org/10.1111/zoj.12051
journal article
10.1111/zoj.12051
0024-4082
4890431
281CB6ED-063E-4CF0-89A2-80EB3761BCDB
NANOTRACHIA CORONATA
SP.
NOV.
Holotype
Australia
,
WA
,
EK
,
Osmond Range
,
17 km
northeast of
Palm Yard
, narrow limestone and sandstone ridge, with steep open slopes, talus, and
Spinifex
, in litter under rocks,
17°12′13″S
,
128°24′50″E
(coll.
V. Kessner
,
29 August 2009
); dissected specimen (
WAM
S66301
).
Paratypes
Same as
holotype
; one wet (
WAM
S49181
), 11 dry (
WAM
S49086
)
.
Other material:
Table 1
.
Etymology
In reference to the crown-like appearance of the peripheral keel because of the axial ribs continuing onto it, derived from ‘coronatus’ (Latin = bearing a crown), adjective of feminine gender.
Description
Shell (
Figs 4C
,
5C, D
):
Large; periphery shouldered, strongly keeled; spire weakly elevated; umbilicus open, wide, not concealed by columellar reflection; protoconch and teleoconch with dense, pointed periostracal projections and fine axial growth lines; teleoconch with weak, blunt, widely spaced axial ribs, not interrupted on keel; apertural lip reflected, moderately expanded; yellowish brown.
Genitalia:
Epiphallus very short, one-quarter of penial length; no muscle fibres connect epiphallus and penial apex. Vas deferens entering penial sheath almost halfway up. Penial wall thin, with two longi- tudinal pilasters, one wide, irregular, comprising half of penial wall, second pilaster thinner, irregularly shaped, winding, with regularly spaced, pointed corrugations; penial pore surrounded by subcircular ridge. Vagina slightly shorter than penis, half to twice as long as free oviduct (identical to
N. carinata
sp. nov.
;
Fig. 6C
).
Comparative remarks
Largest species of genus. Shell similar to
N. carinata
sp. nov.
, but axial ribs continuing on keel;
N. levis
sp. nov.
differing by absence of keel;
N. orientalis
with stronger ribs, other congeners with weaker keel. Genitalia identical to
N. carinata
sp. nov.