Exiligada qualis, IREDALE, 1939

Criscione, Francesco, Law, Margot Louisa & Köhler, Frank, 2012, 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, Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) 166 (4), pp. 689-722 : 710-711

EXILIGADA QUALIS IREDALE, 1939

( FIGS 4E , 6E , 23A–C , 24 )

Exiligada qualis Iredale, 1939: 69 , plate V, figure 2. Exiligada negriensis – Solem, 1984: 673–677,

figure 174 (d–f) (in part).

Material examined: AUSTRALIA, NT, VRD, holotype from 25 miles north of Ord River Station , Negri outstation (coll. R. Helms, 1896), dry ( AM C.64866), 43 paratypes (same data as for holotype) ( AM C.64915); 35 km north of Nicholson H /S, Duncan Rd, limestone cliffs, 500 m west of road, under rocks at dripline of cave overhang, 17°42 ′ 45 ′′ S, 128°50 ′ 10 ′′ E (coll. R. Crookshanks, 28.i.2005), three dry, one wet ( AMS C.443304) .

Duncan Rd , old Ord River homestead, Forrest Ck, 70 km north of Nicholson homestead, under limestone rocks and concrete of old structures, 17°23 ′ 56 ′′ S, 128°52 ′ 01 ′′ E (coll. R. Crookshanks, 29.i.2005), one wet ( AM C.475758) .

Description: Shell ( Figs 4E , 6E , 23A–C ). Moderately large, moderately elevated, moderately thin; teleoconch with short regularly alternate microdepressions. Shell background colour yellowish horn fading to whitish towards shell base, with few conspicuous to moderately faint continuous brown-reddish spiral bands; maculations absent.

Genitalia ( Fig. 24 ). Epiphallus as long as penis. Vas deferens entering penial sheath from halfway up. Penis six times longer than wide, not coiled inside sheath, with inner wall supporting a large apical stimulatory pilaster and (several) basal pilasters. Vagina two thirds of penis and free oviduct, bursa copulatrix with no well-differentiated end.

Remarks: The type locality is identical to that of E. negriensis and as such also restricted to an area close to the Negri River between the point where the Negri River flows into the Ord River in WA (17°04 ′ 11 ′′ S, 128°53 ′ 10 ′′ E) and the Duncan Highway bridge over the Negri River near the WA / NT border relative to width (pl/pw) and epiphallus length relative to penis (el/pl) average. Inner penial wall sculpture similar to those of E. brabyi , to be distinguished by posterior pilaster being continuous. Vagina length relative to penis (vl/pl) average and vagina length relative to free oviduct (vl/ol) half the average.

Figures

Figure 4. Photographs of living specimens of Exiligada species (courtesy Vince Kessner, Adelaide River). A, E. negriensis Iredale, 1939. B, E. pallida sp. nov. C, E. nodulicaudata sp. nov. D, E. punctata sp. nov. E, E. qualis Iredale, 1939. F, E. monochroma sp. nov. G, E. unistriata sp. nov. H, E. floraevallis sp. nov. I, E. rivifontis sp. nov.

Figure 6. Shells of Exiligada species. A, E. montejinni sp. nov. (paratype AM C.469982). B, E. nodulicauda sp. nov. (paratype WAM S49160). C, E. pallida sp. nov. (paratype WAM S49215). D, E. punctata sp. nov. (paratype WAM S49221). E, E. qualis Iredale, 1939 (holotype AM C.64866). F, E. rivifontis sp. nov. (WAM S49225). G, E. unistriata sp. nov. (paratype AM C.470460). Scale bar = 2 mm. Note that foot produces from some shells.

Figure 23. SEM micrographs of Exiligada shells. 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.

Figure 24. Penial anatomy of E. qualis Iredale, 1939 (AM C.475758). Scale bar = 5 mm.