Amplirhagada anderdonensis, Köhler, 2010

Köhler, Frank, 2010, Uncovering Local Endemism in the Kimberley, Western Australia: Description of New Species of the Genus Amplirhagada Iredale, 1933 (Pulmonata: Camaenidae), Records of the Australian Museum 62 (2), pp. 217-284 : 247-249

Amplirhagada anderdonensis n.sp.

Type locality ( Fig. 1 ). Western Australia, Kimberley, Bonaparte Archipelago, Prince Frederick Harbour , Anderdon Islands , unnamed island c. 8 km ENE of Cape Torrens, 14°57'49"S 125°09'30"; KC-084 (leg. V. Kessner & A. Longbottom, 22 July 1988) .

Type material. Holotype WAM S34613 (Pl. 1.19). AMS C463756 (5 preserved specimens), FMNH 219330 (16 preserved specimens), WAM S41492 (10 preserved specimens).

Etymology. In reference to Anderdon Islands, where this species occurs.

Sealing strategy. Rock sealer. Shell ( Fig. 46A–C , Pl. 1.19). Broadly conical with medium high spire, solid. Periphery evenly rounded to slightly angulate; upper and basal sectors of whorls rounded. Umbilicus forming a chink, 90–100 percent concealed by columellar reflection. Background colour greenish ochre to yellowish brown; sub-sutural and mid-whorl band absent or diffuse, darker than background, thin, most conspicuous on last whorl; ventral colour cream; outer lip colour same as shell; inner lip translucent, whitish. Protoconch c. 2 mm in diameter, comprising 1.7 whorls, almost smooth. Teleoconch with inconspicuous axial growth lines, last whorl smooth. Angle of aperture 30°; outer lip rounded, moderate to thick, slightly expanded, slightly reflected; basal node of lip absent or weak; palatal node absent. Parietal wall of inner lip inconspicuous.

Pallial morphology. Pallial cavity deep, extending one whorl. Pigmentation on mantle consists of sparse greyish to brown spots. Kidney extending about half of pallial cavity.

Genital morphology ( Figs. 45 , 47 ). Penis straight to slightly curved, more or less of same length as anterior part of oviduct. Vas deferens coils once before entering penis. Penial retractor muscle shorter than penis. Penial verge moderately long (1 ⁄ 8 – 1 ⁄ 4 penial chamber), slender to spatulate, with pointed tip. Penial wall pustules small, arranged in rows. Main stimulatory pilaster differentiated, relatively thin, cone-shaped, with horizontal ridged that support little hooks, comprising apical to median portion of penial chamber. Vas deferens entering penial sheath in upper third. Vagina moderately long, tubular, posteriorly inflated; inner vaginal wall with smooth longitudinal pilasters. Spermatheca very short, barely reaching base of spermoviduct. Spermathecal duct normal, internally with smooth longitudinal pilasters. Spermathecal head globular, connected with oviduct by connective tissue, internally smooth, with delicate wall. Free oviduct comprising more than half of anterior part of oviduct, more or less straight. Spermoviduct longer than anterior part of oviduct. Talon embedded in albumen gland at junction with spermoviduct.

Radular morphology ( Fig. 46E–G ). Rectangular. Tooth formula C+14–15+2+20–23. In average with 145±12.0 rows of teeth, 31.6±4.2 rows per mm (n = 2). Central teeth with bluntly pointed, ovate mesocones, shorter than base of tooth; ectocones vestigial. Lateral teeth with bluntly pointed, ovate mesocones, length equal to base of tooth; ectocones small, endocones vestigial. Marginal teeth with triangular to rounded mesocones; ectocones shorter and narrower than mesocones; endocones reduced in size.

Comparative remarks. Shell colour very distinctive, similar only to A. tricenaria (see below). Penis proportionally smaller than in other species. In addition, it differs from A. lamarckiana by finer pustulation of inner penial wall and smaller main pilaster. Material of the present species has been labelled as “ Amplirhagada sp. 75” by Solem.

Figures

Figure 1. Distribution of Amplirhagada species in the Kimberley region, northwestern Australia. (1) A. euroa n.sp., Adolphus Island. (2) A. solemiana n.sp., Middle Osborn Island. (3) A. indistincta n.sp., Southwest Osborn Island, Kidney Island. (4) A. combeana, Cassini Island. (5) A. mckenziei n.sp., Oliver Island. (6) A. ponderi n.sp., Kingsmill Island. (7) A. montesquieuana n.sp., Fenelon Island. (8) A. descartesana n.sp., Descartes Island. (9) A. katerana, Katers Island. (10) A. puescheli n.sp., unnamed island near Prudhoe Island. (11) A. decora n.sp., A. kessneri n.sp., Bigge Island. (12) A. berthierana n.sp., Berthier Island. (13) A. lamarckiana n.sp., Lamarck Island.(14) A. anderdonensis n.sp., unnamed island, Anderdon Islands. (15) A. tricenaria n.sp., Prince Frederick Harbour, north of Hunter River mouth. (16) A. regia n.sp., A. boongareensis n.sp., A. gibsoni n.sp., and Amplirhagada sp., Boongaree Island. (17) A. yorkensis n.sp., Coronation Island. (18) A. buffonensis n.sp., Buffon Island. (19) A. uwinsensis n.sp., Uwins Island. (20) A. sphaeroidea n.sp., St. Andrews Island. (21) A. basilica n.sp., and A. camdenensis n.sp., Augustus Island. (22) A. kimberleyana n.sp., NW of Wilson Point. (23) A. gemina n.sp., 1.5 km SE of Hall Point. (24) A. dubitabile n.sp., Steep Island. (25) A. napierana, north Napier ranges. (26) A. percita, Napier ranges. (27) A. castra, A. mitchelliana, and A. varia, Mitchell Plateau.

Figure 45.Genitalia of Amplirhagadaanderdonensis n.sp., paratype FMNH 219330 (22 July, scale 10 mm). Compare with Fig. 3 for labelling of structures.

Figure 46. SEM photographs of Amplirhagada anderdonensis n.sp. (A–C) Shell, paratype AMS C463756: (A) apical whorl viewed from above (scale 200 µm); (B) sculpture on second and third whorl viewed from above (scale 200 µm); (C) sculpture on upper part of last whorl (scale 100 µm). (D) Jaw (scale 100 µm). (E–G) Radula, paratype FMNH 219330: (E) central and lateral teeth (scale 20 µm); (F) close-up of lateral teeth (scale 10 µm); (G) outer lateral and inner marginal teeth (scale 10 µm).

Figure 47. Interior of penial chamber of Amplirhagada anderdonensis n.sp., paratype FMNH 219330 (22 July, scale 5 mm). Compare with Fig. 4 for labelling of structures.