Molecular phylogenetics and complementary geographical distributions of species of the Western Australian land snail genera Plectorhagada Iredale, 1933 and Strepsitaurus Solem, 1997 (Gastropoda: Camaenidae) Author Taylor, James P. A. Author Johnson, Michael S. Author Stankowski, Sean text Zoological Journal of the Linnean Society 2015 2015-05-14 174 2 305 321 http://dx.doi.org/10.1111/zoj.12238 journal article 10.1111/zoj.12238 0024-4082 5338011 STREPSITAURUS MANDUENSIS SP. NOV. FIGURES 1 , 3 , 7 , 12 Type locality Western Australia , Cape Range , Mandu Mandu Gorge ( 22°08′59.7″S , 113°53′14.7″E ) . Material examined Holotype WAM S67369 . Paratypes WAM S67370, S67371 . Etymology Refers to Mandu Mandu Gorge. Description Holotype : shell 7.4 mm wide, 3.3 mm high, H / D ratio 0.45, with 3.5 whorls. Based on ten measured adults, shell small, adult diameter 6.8–7.6 mm (mean 7.19 mm , SD 0.26 mm ), with 3.33–3.63 (mean 3.5) whorls. Apex and spire evenly elevated, shell height 3.0– 3.5 mm (mean 3.23, SD 0.13 mm ), H / D ratio 0.407 –0.479 (mean 0.449, SD 0.020). Body whorl rounded, without trace of angulation. Protoconch densely pustulose. Early spire with prominent pustules but only weak axial ridges. Lower spire and body whorl with faint, deeply pustulose diagonal ridges above periphery, ridges becoming even less prominent on shell base. Umbilicus wide, regularly decoiling, slightly narrowed by columellar lip, width 1.5–1.9 mm (mean 1.67 mm , SD 0.15 mm ). Body whorl descending sharply behind aperture. Palatal and basal lips sharply reflected and broadly expanded, and columellar lip wide, parietal lip free of wall and strongly elevated. Basal lip without knob on top of lip. Shell colour white on top of ridges, reddish to purplish brown in interstices. Comparative remarks Strepsitaurus manduensis sp. nov. is similar to S. milyeringus and S. susieae sp. nov. , with these three species differing from S. ningaloo , S. rugus , and S. williami by their smaller size, lower whorl count, lips distinctly detached from the body whorl, and lack of setae on the shell. They also lack the prominent knob on the basal lip, which characterizes S. williami ( Solem, 1997 ) . Strepsitarus manduensis sp. nov. is distinguished largely from S. milyeringus and completely from S. susieae sp. nov. by its relatively low spire [mean H / D 0.449 ( 0.407 –0.479 ), compared with 0.484 ( 0.443 – 0.548 ) and 0.575 ( 0.544 –0.597 )], and its less developed ridges. Figure 12. Shells of Strepsitaurus milyeringus (A–C), and holotypes of Strepsitaurus susieae sp. nov. (D–F) and Strepsitaurus manduensis sp. nov. (G–I). Distribution This species is known only from Mandu Mandu Gorge, on the western side of Cape Range, where it was found on vertical rock faces on the north side of the gorge, at two sites 560 m apart. It was not found above the gorge, where the larger S. ningaloo occurs.