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