Land snail diversity in the monsoon tropics of Northern Australia: revision of the genus Exiligada Iredale, 1939 (Mollusca: Pulmonata: Camaenidae), with description of 13 new species
Criscione, Francesco
Law, Margot Louisa
Köhler, Frank
Zoological Journal of the Linnean Society
2012
Zool. J. Linn. Soc.
2012-11-26
166
4
689
722
3DL88
Criscione & Law & Köhler, 2012
Criscione & Law & Köhler
2012
[943,1213,426,447]
Gastropoda
Camaenidae
Exiligada
Animalia
Stylommatophora
23
712
Mollusca
species
rivifontis
sp. nov.
( FIGS 4I, 6F, 23D–E, 25) Holotype: AUSTRALIA, NT, VRD, 30.4 kmeast-southeast of Spring Creek StationH/S, limestone gully along a stream, cliffs 8–10 mhigh, base of limestone cliffs along a seasonal stream, talus, spinifex and native grass, in talus. 17°02 ′04 ′′S, 129°08 ′35 ′′E(coll. V. Kessner, R. Hokkanen, 30.viii.2009; WA-67/09) ( WAMS83176). Figure 21.Penial anatomy of E. pallida sp. nov.(holotype WAM S83174). Scale bar = 5 mm. Figure 22.Penial anatomy of E. punctata sp. nov.(holotype WAM S83175). Scale bar = 5 mm. ( 17°04 ′32 ′′S, 129°00 ′10 ′′E). The species is removed from the synonymy of E. negriensis. Together with E. nodulicaudait has the narrowest umbilicus in the genus. Teleoconch microsculpture is unique in being composed of regularly arranged microdepressions rather than micropustulations. Shell colour pattern not easily distinguished from E. brabyi. Penis length Paratypes:Same data as for holotype, four wet (WAM S49224). Other material: AUSTRALIA, NT, VRD, 28.2 kmeast of Spring Creek StationH/S, base of limestone cliffs 15–20 mor higher, large overhangs, in talus and under boulders, 17°00 ′44 ′′S, 129°07 ′35 ′′E(coll. V. Kessner, R. Hokkanen, 30.viii.2009; WA-66/09), three wet ( WAM S49225); 30.4 kmeast-south-east of Spring Creek StationH/S, limestone gully along a stream, cliffs 8–10 mhigh, base of limestone cliffs along a seasonal stream, spinifex and native grass, in talus, 17°02 ′04 ′′S, 129°08 ′35 ′′E(coll. V. Kessner, R. Hokkanen, 30.viii.2009; WA-67/09), three dry ( WAM S94141); AUSTRALIA, WA, EK, 1.7 kmsouth of Behn Rivercrossing, limestone ridge west of Duncan Hwy, east large open limestone ridge, very small vine thicket patches, dead in rock piles, 16°35 ′48 ′′S, 128°57 ′10 ′′E(coll. V. Kessner, R. Hokkanen, 27.viii.2009; WA-54/09), five dry ( WAM S49140); 12.3 kmeast of Spring Creek StationH/S, low exposed hills with small 2–3-m-high limestone cliffs east of Duncan Hwy, spinifex, few fig trees, dead under talus, 16°59 ′57 ′′S, 128°58 ′34 ′′E(coll. V. Kessner, R. Hokkanen, 30.viii.2009; WA-70/09), one dry ( WAM S49142); Halls Creek District, 57 kmeast of Nicholson StationH/S, very open limestone area, well-developed spinifex, talus under spinifex, 17°58 ′43 ′′S, 128°21 ′34 ′′E(coll. V. Kessner, R. Hokkanen 1.ix.2009; WA-75/09), two dry ( WAM S49143). Etymology:In reference to Spring Creek, close to typelocality, Latinized and derived from ‘rivus’ (Latin = creek) and ‘fons’ (Latin = spring), nouns of respectively masculine and feminine gender in genitive case. Description:Shell ( Figs 4I, 6F, 23D, E). Large, strongly elevated, moderately thin; micropustulations present. Shell background colour brown horn fading to whitish towards shell base, with one faint to conspicuous continuous narrow brown-reddish spiral band on whorl periphery; maculations absent. Figure 23.SEM micrographs of Exiligadashells. A-C, E. qualis Iredale, 1939(paratype AM C.64915). A, Apical view showing protoconch and first whorl. B, Close-up from above of sculpture across entire shell. C, Microsculpture on teleoconch whorl. D-F, E.rivifontis sp. nov.(WAM S49141). D, Apical view showing protoconch and first whorl. E, Close-up from above of sculpture across entire shell. F, Microsculpture on teleoconch whorl. Scale bars: A-B, D-E = 1 mm, C, F = 0.5 mm. Genitalia ( Fig. 25). Epiphallus two times longer than penis. Vas deferens entering penial sheath from one third up. Penis three times longer than wide, not coiled inside sheath, with inner wall supporting several moderately large, irregularly shaped longitudinal pilasters, often not running along entire wall length. Vagina two times shorter than penis and free oviduct, bursa copulatrix with short, rounded welldifferentiated end. Remarks:Highest shell, largest shell diameter, and largest number of shell whorls (together with E. gregorianaand E. rivifontis) within genus. Colour pattern very similar to E. calciphila, E. floraevallis, E. gregoriana, E. limbunya, and E. unistriata. Penis length relative to width (pl/pw) smaller than the average and E. rivifontis; epiphallus length relative to penis (el/pl) 1.5 times the average and as large as in E. floraevallis. Penial inner wall sculpture very similar to E. floraevallisand not easily distinguishable. Vagina length relative to penis (vl/pl) average and as large as in E. floraevallis, vagina length relative to free oviduct (vl/ol) smaller than average and E. floraevallis.
S83176
2009-08-30
NT, VRD, WAM
Spring Creek Station H & V. Kessner & Kessner, R
Australia
9
-17.034445
Spring Creek Station
21
129.14305
23
712
WA-67
1
holotype
[1033,1327,840,861]
NT, VRD
Australia
AUSTRALIA
23
712
1
S49225, S94141
2009-08-30
WAM
V. Kessner & R. Hokkanen
Australia
18
-17.034445
Spring Creek Station
21
129.14305
Spring Creek Station
23
712
WA-66, WA-67
1
[1044,1335,1177,1198]
WA, EK
Australia
AUSTRALIA
23
712
1
S49140, S49142, S49143
2009-08-27
2009-09-01
2009-08-27
WAM
V. Kessner & R. Hokkanen & Spring Creek Station H & Nicholson Station H
Australia
Nicholson Station
-17.978611
Behn River
21
128.35945
Halls Creek District
23
712
WA-54, WA-70, WA-75
1