Amplirhagada atlantis, Köhler, 2011

Köhler, Frank, 2011, Descriptions of New Species of the Diverse and Endemic Land Snail Amplirhagada Iredale, 1933 from Rainforest Patches across the Kimberley, Western Australia (Pulmonata: Camaenidae), Records of the Australian Museum 63 (2), pp. 167-202 : 170-172

Amplirhagada atlantis n.sp.

Type locality. Western Australia, NW Kimberley, Joseph Bonaparte Gulf, 8.6 km SSE of Cape Bernier ; 14°04'40"S 127°29'25"E (RFS-04-1; coll. V. Kessner, 04 Jun 1987) ( Fig. 1 ) .

Type material. Holotype WAM S34704 (preserved specimen) (Pl. 1.1; Table 1) . Paratypes AM C.472918 (4 preserved specimens), WAM S34705 (8 preserved specimens) , FMNH 220006 (12 preserved specimens) , AM C.472919 (3 dried shells), WAM S34706 (10 dried shells) , FMNH 220005 (13 dried shells) .

Additional material (not dissected). WAM S34751 (5 preserved specimens), FMNH 220327 (10 preserved specimens), WAM S34752 (8 dried shells), FMNH 220328 (7 dried shells), all from 5.6 km W of Evelyn Island , mainland, behind beach and mangroves; 14°06'55"S 127°31'10"E ( RFS 10-2 ; coll. V. Kessner, 10 Jun 1987) .

Etymology. Specific name referring to the name of the seaplane “Atlantis 1925” of the two German aviators Hans Bertram and Adolph Klausmann, who in 1932 undertook a goodwill flight from Cologne, Germany, to Australia. On 14 May 1932 the aviators took off from Timor bound for Darwin but were stranded due to bad weather near Bertram Cove, where they survived for 40 days before being rescued. Being a noun the species epithet keeps its male suffix.

Description

Shell (Pl. 1.1, Fig. 2A–C ). Broadly conical with moderately elevated spire. Rather thin but solid, translucent. Periphery well rounded to slightly angulate; upper and basal sectors rounded. Umbilicus 80–90% concealed by columellar reflection. Background colour horn to almost crème; no spiral bands visible; outer and inner lip colour whitish. Protoconch 2.6 mm in diameter, comprising about 1.5 whorls, with weak radially elongated pustulations. Teleoconch with faint, regular axial growth lines, evenly distributed across whorls of shell and across whorl diameter. Angle of aperture 45–60 degrees; outer lip thin, well rounded, well expanded, not or slightly reflected; basal node absent or weak. Parietal wall of inner lip inconspicuous. Average shell size 11.8±0.8 × 16.2± 0.9 mm ( Table 1).

Radular and jaw morphology ( Fig. 2 D–G ). Tooth formula C + 14 + 4 +?; average number of rows of teeth 130 (n = 2). Jaw with nine plates.

Genital morphology ( Figs 3–4 ). Penis straight, more or less of same length as anterior part of oviduct. Penial sheath delicate. Length of penial retractor muscle equivalent to about ¼ of length of penial complex. Penial verge extending about ¼ of length of penial chamber, slender with rounded tip. Almost entire inner penial wall covered by strongly developed pustules, which are arranged to form several corrugated longitudinal pilasters. Main stimulatory pilaster well developed, elongate, comprising proximal third of inner penial wall; sculptured by smooth lateral ridges being formed by fused and flattened pustules. Vas deferens entering penial sheath near apex of penial complex. Vagina long, tubular, posteriorly slightly inflated; inner vaginal wall and inner wall of spermathecal duct support continuous, welldeveloped, smooth longitudinal pilasters. Bursa copulatrix short, reaching base of spermoviduct; head elongately inflated, connected with spermoviduct by connective tissue, wall of head delicate, smooth. Free oviduct rather straight comprising less than half of length of anterior part of oviduct. Spermoviduct longer than anterior part of oviduct.

Aestivation strategy. Free or rock sealer, in talus throughout vine thicket patches.

Remarks. Anatomical description based on dissections of two type specimens. The non-type sample contains predominantly immature individuals not suitable for anatomical dissections. Listed by Solem (1991) as “ Amplirhagada NSP 17”.

Figures

Figure 1. Distribution of Amplirhagada species described in the present work. (A) A. atlantis n.sp. (B) A. carsoniana n.sp. (C) A. alicunda n.sp. (D) A. davidsoniana n.sp. (E) A. vialae n.sp. and A. discoidea n.sp. (F) A. forrestiana n.sp. (G) A. inusitata n.sp. and A. epiphallica n.sp. (H) A. lindsayae n.sp. (I) A. angustocauda n.sp. (K) A. moraniana n.sp. (L) A. gardneriana n.sp. (M) A. bendraytoni n.sp. (N) A. coffea n.sp. (P) A. carinata Solem, 1981. When species occur at more than one locality, the type locality of newly described taxa is marked with an asterisk.

Figure 2. Amplirhagada atlantis n.sp. SEM of shell (AM C.472919), radula and jaw (AM C.472918). (A) Protoconch viewed from above. (B) Detail of first teleoconch whorls viewed from above. (C) Close-up showing sculpture on last whorl. (D) Jaw. (E) Close-up showing morphology of central and inner lateral teeth.(F) Central and lateral teeth viewed from above.(G) Inner and central marginal teeth viewed from above. Scale bars: A–C, 200 µm; D, 100 µm; E–F, 20 µm; G, 10 µm.

Figure 3. Genitalia of Amplirhagada atlantis n.sp. (AM C.472918). Abbreviations: ag, albumen gland; bc, bursa copulatrix; fo, free oviduct; hd, hermaphroditic duct; p, penis; rm, penial retractor muscle; so, sperm oviduct; va, vagina; vd, vas deferens. Scale bar = 5 mm.

Figure 4. Penial anatomy of Amplirhagada atlantis n.sp. (AM C.472918). Abbreviations: mp, main pilaster; ps, penial sheath; pu, penis wall pustulation; pv, penial verge; rm, penial retractor muscle; vd, vas deferens. Scale bar = 3 mm.