Rec. West. Aust. Mus., Suppl. no. 11, 1981 CAMAENID LAND SNAILS FROM WESTERN AND CENTRAL AUSTRALIA (MOLLUSCA: PULMONATA: CAMAENIDAE) 11 TAXA FROM THE KIMBERLEY, AMPLIRHAGADA IREDALE, 1933 ALAN SOLEM* [Received 25 September 1978. Accepted 8 February 1979. Published 30 Apri11981.] INTRODUCTION This is the second report on the semi-arid zone dominant land snails of Western and central Australia, which belong to the Camaenidae, sensu lato. It reviews 28 species­ level taxa in Amplirhagada Iredale, 1933, a genus apparently restricted to and undergoing extensive speciation in the Kimberley Region. Part I of this series (Solem, 1979) covered the genera with trans-Australian distributions (Hadra Albers, 1860; Xanthomelon von Martens, 1860; Damochlora Iredale, 1938; and Torresitrachia Iredale, 1939), plus related Chloritis-like genera from eastern Australia. Major financial sponsorship of this co-operative project between the Western Australian Museum, Perth (hereafter WAM) and Field Museum of Natural History, Chicago (hereafter FMNH) has been provided by National Science Foundation Grant DEB 75-20113 to FMNH for fieldwork and subsequent studies of collected materials, and National Science Foundation Grant BMS 72-02149 that established a scanning electron microscope laboratory at FMNH. Grateful acknowledgment is made of this support. All line illustrations and charts are by Elizabeth A. Liebman, formerly Illustrator, Division of Invertebrates, Field Museum of Natural History. For aid in mounting and labelling plates and figures, we are indebted to Dorothy Karall. For help with specimen measurements, loan shipments, and compiling lists of materials studied, I am indebted to Margaret Baker, D.A. Cawthon, Kleinie Fieberg, Jermaine Leftridge, Joseph Strotter, and Loretta Brown. Final manuscript typing, proofreading, and editing for consistency have been handled very efficiently by Valerie Connor-Jackson, Secretary, Division of Invertebrates. *Field Museum of Natural History, Chicago, Illinois 60605 D.S.A. 147 LIST OF TAXA Genus Amplirhagada Iredale, 1933 (+ Thetagada Iredale, 1939; Tenuigada Iredale, 1939) A. drysdaleana sp. noy.: 185 A. questroana sp. noy.: 188 A. pusilla sp. noy.: 194 A. katerana sp. noy.: 198 A. kalumburuana sp. noy.: 202 A. carinata sp. noy.: 205 A. astuta (Iredale, 1939): 208 A. percita (Iredale, 1939) (+ Tenuigada ignara Iredale, 1939): 211 A. napierana sp. noy.: 225 A. burnerensis burnerensis (Smith, 1894) (+ A. terma Iredale, 1939): 233 A. b. umbilicata subsp. noy.: 248 A. elevata sp. noy.: 250 A. wilsoni sp. noy.: 257 A. alta alta sp. et subsp. noy.: 263 A. a. crystalla subsp. noy.: 267 A. a. intermedia subsp. noy.: 270 A. alta subsp.: 272 A. mitchelliana sp. noy.: 272 A. confusa sp. noy.: 280 A. castra sp. noy.: 286 A. varia varia sp. et subsp. noy.: 294 A. v. depressa subsp. noy.: 300 A. sykesi (Smith, 1894): 302 A. montalivetensis (Smith, 1894): 305 A. imitata (Smith, 1894) (+ A. burrowsena Iredale, 1939): 306 A. combeana Iredale, 1938 (= Helix imitata Yar. cassiniensis Smith, 1894): 310 A. novelta Iredale, 1939: 313 A. herbertena Iredale, 1939: 315 SYSTEMATIC REVIEW GENUS AMPLIRHAGADA IREDALE, 1933 Amplirhagada Iredale, 1933, Records Australian Mus., 19: 52-type species Helix (Hadra) sykesi Smith, 1894 by original designation; Iredale, 1938, Australian Zool., 9 (2): 113-1l4-list of species; Iredale, 1939, Jour. Roy. Soc. Western Australia, 25: 65-68-monograph of genus. Thetagada Iredale, 1939, Jour. Roy. Soc. Western Australia, 25: 63-nude name for Rhagada astuta Iredale, 1939. Tenuigada Iredale, 1939, Jour. Roy. Soc. Western Australia, 25: 68-type species 'Tenuigada percita Iredale, 1939 by original designation. 148 Diagnosis Shell generally medium in size, spire moderately to strongly and evenly elevated, occasionally dome-shaped, umbilicus narrowly open to completely closed by reflected lip, rarely with a closing callus. Apical sculpture of radially elongated pustulations, varying from fine (Plate 14e) to very coarse (Plate 13d), sometimes (Plate 14d) coalesced into weak radial ribs. Postapical sculpture above periphery ranging from very weak radial growth lines (Plate 14e) to very sharply defined radial ribs (Plate 12e) or grossly broadened radial ribs (Plate 12b). Shell base with incised spiral lines (Plate 14f) that extend onto spire when radial ribbing greatly reduced. Body whorl not (Fig. 43f) to sharply (Fig. 67e) deflected behind lip, which is usually sharply reflexed and expanded in adults, but occasionally only slightly expanded. Shell periphery evenly rounded to occasionally carinated (Fig. 43a). Basal lip without to with a high tuberculate protrusion (Fig. 59f), parietal wall with a thin callus. Shell colour variable, white in A. napierana, horn coloured in A. percita (Iredale, 1939), horn coloured with reddish markings in remaining species. Typically with both a subsutural and a supraperipheral spiral colour band, a small to extensive columellar colour patch in species with a closed umbilicus, and an individually variable reddish suffusion on the spire, some features lacking in some species. Genitalia with size of ovotestis seasonally variable, size and shape ofhermaphroditic duct also correlated with activity stage, talon (GT) receiving hermaphroditic duct laterally except in A. questroana (Fig. 40a) where the insertion is almost terminal. Spermatheca (S) normally with expanded base, narrowed shaft and ovate head that lies just above vas deferens-free oviduct origin. Interior of spermatheca base and vagina (V) normally (Fig. 64a) with harrow corrugated pilasters and a ridged, highly expandable pad surrounding opening of free oviduct (UVO), altered (Fig. 64b) under conditions of sympatry. Length of free oviduct (UV) and vagina (V) variable among species. Penis complex with a thin, expandable sheath extending from slightly above atrium (Y) to insertion of penis retractor muscle (PR) onto vas deferens (VD). No epiphallus or caeca on male system. Vas deferens (VD) entering penis sheath from halfway up to near apex, usually folded in an S-loop to tightly coiled below insertion of vas deferens, except immediately after mating and for the next few days. Vas deferens entering penis through a short (Fig. 57a) to very long (Figs 66a-b) tubular to conical verge (PV) with terminal and usually simple pore. Tip ofverge modified in two Napier Range taxa (Figs 51b-e). Walls ofpenis chamber with basal ridges (PP) of variable length, pustules (PPR) on upper wall except in A. elevata, a main stimulatory pilaster (PT) surmounted by narrow to wide corruga­ tions whose anterior edges are lined with a few to many sharp points (Figs 36-37). Main pilaster secondarily greatly reduced (Figs 36d-f) under congeneric sympatry. Type species: Helix (Hadra) sykesi Smith, 1894 by original designation. Previous studies and nomenclature Smith (1894) described a few specimens collected in the Napier Range by W.W. Froggatt before 1884 and by J.J. Walker, an officer on the survey ship Penguin 149 during its charting of Montague Sound and the Admiralty Gulf in 1890 and 1891: Amplirhagada sykesi (Smith, 1894), A. imitata (Smith, 1894), A. montalivetensis (Smith, 1894), A. burnerensis (Smith, 1894), and A. combeana Iredale, 1938 (new name for Helix imitata var. cassiniensis Smith, 1894 not Helix millepunctata var. cassiniensis Smith, 1894) date from this study. Iredale (1933, 1938) provided a cryp­ tic description of the genus and a few years later he published a list of species and the needed substitute name. The only major study, Iredale (1939), resulted in the pro­ posal of several species names and two generic names. Tenuigada is a subjective synonym of Amplirhagada and Thetagada is a nude name for A. astuta (Iredale, 1939). Of the species proposed by Iredale, Amplirhagada herbertena Iredale, 1939, A. novelta Iredale, 1939, and Rhagada astuta Iredale, 1939 were based on single worn shells. Only the latter is represented in collections by additional specimens. A. burrowsena Iredale, 1939 is here considered to be a synonym of A. imitata (Smith, 1894); A. terma Iredale, 1939 is based on small examples from the type lot of A. burnerensis burnerensis (Smith, 1894); and Tenuigada ignara Iredale, 1939 is placed as a synonym of A. percita (Iredale, 1939), since both names were based on shells from the same lot. Except for the above descriptions, no data has been recorded in the literature on either shell variation or anatomical structures. Amplirhagada was well described by Iredalean standards. Although the type species has not been dissected, its close similarity to the Mitchell Plateau taxa leaves little doubt but that it is correctly referred to this genus. Thetagada Iredale (1939: 63) was not adequately diagnosed and is consid~red to be a nude name, since'...this species may prove very distinct, and in order to keep this point in view a new subgeneric name, Thetagada, with this {Rhagada astuta] as type, is introduced' hardly qualifies as a valid description. Tenuigada Iredale (1939: 68) was adequately described, but in anatomy is only slightly different (Figs 5Ib-c) from A. napierana, a nearly typical Amplirhagada in all but colour and shell sculpture. Tenuigada is thus a subjective synonym of Amplirhagada. Distribution and basic ecology Amplirhagada was not collected in the Ningbing Ranges, but has been found near El Questro Station south of Wyndham. The genus (Fig. 73) has been then found in the Drysdale River Reserve and near Kalumburu Mission. It then ranges south to Koolan Island, Harding Range, and Napier Range, but is absent from the Oscar Range and the many ranges between there and Halls Creek. Discussion of distribu­ tion and species identification has been presented after the species accounts because of the mosaic pattern of structural variation and rather extensive sympatry. Throughout most of its range, Amplirhagada is rock associated, primarily talus situations, but species also aestivate in crevices of large boulders or on the roof and walls of caves. Many of the species seal themselves to rocks or other shells, but others such as A. mitchelliana, A. castra, and A. carinata are 'free sealers', lying at 150 the soil surface under logs or rocks and secreting a recessed calcified epiphragm across the aperture.
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