Innesoconcha princeps, IREDALE, 1944

Hyman, Isabel T., Caiza, Jennifer & Köhler, Frank, 2023, Dissecting an island radiation: systematic revision of endemic land snails on Lord Howe Island (Gastropoda: Stylommatophora: Microcystidae), Zoological Journal of the Linnean Society 197 (1), pp. 20-75 : 68

INNESOCONCHA PRINCEPS IREDALE, 1944

( FIGS 5J , 6H, I , 11 , 22D–F , 24 ; TABLE 1 )

Innesoconcha princeps Iredale, 1944: 326 , pl. 20, fig. 5; Smith, 1992: 235; Stanisic et al., 2010: 344–345; Hyman & Köhler, 2020: 102–103.

Type material: Syntypes, AM C.38958 ( Fig. 5J ), Mount Gower (31°35.4′S, 159°4.35′E), 1912 , R. Bell .

Material examined: See Table 1 .

Description

External morphology: Shell ( Fig. 5J ) small ( SW 8.8–9.1 mm, SH 4.5–5.5 mm), 4.9–6.0 whorls, glossy, light golden-brown with a darker brown peripheral stripe, appearing darker in live specimens, depressed trochoidal with a low spire. Protoconch and teleoconch sculptured with fine, incised spiral grooves. Whorls flattened above and rounded below an angulate periphery; sutures weakly impressed. Animal ( Fig. 6H, I ) pale to dark grey in life, faded to cream in alcohol. Right and left shell lappets narrow, finger-shaped. Caudal horn moderately large; caudal foss a vertical slit in tail.

ReproductiƲe system ( Fig. 24 ): Oviduct with 22 eggs, seven embryos. Penis long, coiled in tunica; epiphallus enters penis through a simple pore; penis internally flat, two longitudinal penis pilasters present. Penial tunica enclosing coiled penis and epiphallus; penis retractor muscle attached to penis and adjacent epiphallus. Epiphallus shorter than penis, internally with longitudinal pilasters. Spermatophore small, softwalled capsule, closed at both ends, one end rounded, one pointed.

Radula ( Fig. 22D–F ): Central and lateral tooth mesocones approximately equal in length to tooth base. Marginal teeth multicuspidate. Radular formula (70.7.1.7.70) × 103.

Figures

Figure 5. Shells of Innesoconcha.A,B,Innesoconcha catletti.A,AM C.101187 (syntype).B, AM C.101188 (syntype of I.catletti major). C, Innesoconcha aberrans, AM C.63475 (holotype). D, Innesoconcha delecta, AM C.63478 (holotype). E, Innesoconcha doppelganger sp. nov., AM C.592779 (holotype). F, Innesoconcha flaƲescens, AM C.40600 (syntype). G, Innesoconcha grata, AM C.63479 (lectotype). H, Innesoconcha miranda, AM C.39175 (holotype). I, Innesoconcha prensa, AM C.63476 (holotype). J, Innesoconcha princeps, AM C.38958 (syntype). K, L, Innesoconcha rosacea. K, AM C.38940 (holotype). L, AM C.63477 (holotype of Melloconcha alma). M, Innesoconcha segna, AM C.114789 (possible holotype).

Figure 6. Live individuals of Innesoconcha. A, Innesoconcha catletti, AM C.532582, Research Station. B, Innesoconcha aberrans, AM C.593857, Mount Lidgbird mid-south-western slopes. C, Innesoconcha delecta, AM C.574679, Mount Gower summit. D, Innesoconcha flaƲescens, AM C.532623, Boat Harbour. E, I. flaƲescens, AM C.574741, Mount Lidgbird lower northern slopes. F, Innesoconcha grata juvenile, AM C.593.893, Mount Lidgbird mid-south-western slopes. G, Innesoconcha prensa, AM C.583114, Mount Gower summit. H, Innesoconcha princeps, AM C.574711, Mount Gower summit. I, I. princeps juvenile, AM C.574683, Mount Gower summit. J, Innesoconcha rosacea, AM C.583117, Dinner Run. Images by A. Moussalli (A, D), C. Stehn (B, C, E, F, H, I) and F. Köhler (G, J).

Figure 11. Map showing the ranges of Innesoconcha catletti, Innesoconcha doppelganger sp. nov., Innesoconcha princeps and Innesoconcha segna.

Figure 22. Radulae. Column one shows central tooth and adjacent laterals, column two shows the transition between lateral and marginal teeth, and column three shows the outer marginal teeth. A–C, Innesoconcha prensa, AM C.91378, Mount Gower. D–F, Innesoconcha princeps, AM C.91377, Mount Gower. G–I, Innesoconcha rosacea, AM C.391700, Old Settlement Beach. Scale bars: 20 µm (A–F); 10 µm (G–I).

Figure 24. Reproductive system of Innesoconcha princeps. A, AM C.91337, Mount Gower summit, reproductive system. B, C, AM C.574711, Mount Gower summit. B, penis with tunica opened. C, penis interior. Scale bars: 1 mm.