Mysticarion hyalina ( Pfeiffer, 1855 )

Hyman, Isabel T. & Ponder, Winston F., 2010, A morphological phylogenetic analysis and generic revision of Australian Helicarionidae (Gastropoda: Pulmonata: Stylommatophora), and an assessment of the relationships of the family 2462, Zootaxa 2462 (1), pp. 1-148 : 38-40

Mysticarion hyalina ( Pfeiffer, 1855)

Figures 5C , 7G , 8G , 9G , 12D , 13D , 15G–I

Vitrina hyalina Pfeiffer, 1955: 296–297 ; Reeve, 1862: pl. 9, sp. 68; Cox, 1868: 85, pl. 14, figs 7, 7a; Pfeiffer, 1876: 24; Smith, 1992: 244 (in Incertae Sedis).

Vitrina hyalinus: Cox, 1909: 6 .

Helicarion hyalinus: Tryon, 1885: 172 , pl. 39, figs 75–76; Hedley, 1888: 50; Iredale, 1937c: 8.

Material examined. Queensland, Australia: Holotype: BMNH 1983075 (one shell measured, photographed). Moreton Bay .

Other material: AM C128630 (one specimen dissected, radula examined), Cunningham’s Gap , N of Mt. Mitchell (28º3' S, 152º24' E), on Gap Creek, rainforest with palms, 16 Mar. 1981, W.F. Ponder & party .

Description. External morphology: Shell ( Figures 7G , 8G , 9G ) reduced, 4 whorls, light amber, spire and apex slightly raised, shape and sculpture as for genus. Animal ( Figure 5C ) cream. Mantle laps moderately short, wide at base, rapidly tapering, not fused, uniform in colour. Mantle lobes of medium size, left and median mantle lobes fused. Caudal horn medium; caudal foss diamond-shaped slit in tail.

Mantle cavity: As for genus. Mantle with very few visible minor blood vessels, pigmentation of white spots.

Digestive system: As for genus.

Genital system ( Figures 12D , 13D ): Free oviduct long, with one internal longitudinal pilaster (only present after capsular gland). Penis moderately long; epiphallus enters penis through short verge (about a quarter of penis length); penis internally flat, one longitudinal penis pilaster present. Epiphallus approximately equal to penis length, internally with longitudinal pilasters.

Radula ( Figure 15G–I ): As for genus. Central tooth mesocone similar in length to tooth base. Marginal teeth subdivided into three to four extra teeth. Radular formula (91.8.1.8.91) × at least 116 rows.

Range and habitat. Mysticarion hyalina has a small range, reaching from around Tenterfield and Casino in northern New South Wales to Cunningham’s Gap just north of the New South Wales-Queensland border. It is found in notophyll to microphyll vine thickets. No microhabitat data are available.

Remarks. This shell was originally described as depressedly globose, with type measurements of 7 mm (diameter) by 3.5 mm (height) ( Pfeiffer 1855). The shell figured by Reeve (1862) matched this description; however, subsequent authors figured a more reduced, more flattened shell ( Cox 1868; Tryon 1885), and Iredale (1937c) synonymised the species with Peloparion helenae . Examination of the holotype (shell only; Figures 7G , 8G , 9G ) indicated that this species belongs to the genus Mysticarion .

Figures

FIGURE 5. External morphology of semislugs. A. Helicarion cuvieri, AM C424333 (Corinna, TAS). B. Mysticarion porrectus, QMMO29298 (Robertson, SE NSW). C. Mysticarion hyalina, AM C128630 (Cunningham’s Gap, SE QLD). D. Parmavitrina planilabris, AM C334357 (Wauchope, NSW). E–F. Peloparion helenae, AM C205295 (Barrington Tops, NSW). G. Stanisicarion virens, QMMO19234 (Brisbane, SE QLD). Scale bars 2 mm (B–C, E–G), 5 mm (A), 10 mm (D). Abbreviations: cah, caudal horn; cp, caudal pit; lla, left mantle lap; mlo, median mantle lobe; rla, right mantle lap; rlo, right mantle lobe; sh, shell.

FIGURE 7. Shells, dorsal view. A. Helicarion cuvieri, AM C443929. B. Helicarion cuvieri, BMNH 197780 (S of Vitrina verrauxii). C. Helicarion mastersi, AM C101139 (H). D. Helicarion mastersi, AM C101138 (PRH of H. mastersi callidus). E. Mysticarion insuetus, AM C113776 (S). F. Mysticarion porrectus, AM C101136 (PRH). G. Mysticarion hyalina, BMNH 1983075 (H). H. Parmavitrina planilabris, AM C103630. I. Peloparion helenae, AM C101142 (H). J. Brevisentis jacksoniensis, BMNH not registered (S). K. Brevisentis jacksoniensis, AM C101143 (H of B. exclusus). L. Fastosarion superba, BMNH not registered (POS). Scale bars 3 mm (G, I–K), 5 mm (A–F, H), 10 mm (L). Photographs by M. Allan (D, I), H. Barlow (A, C, H), D. Beechey (E–F, K), W. Ponder (B, G, J, L). Abbreviations: H, holotype; POS, possible syntype; PRH, probable holotype; S, syntype.

FIGURE 8. Shells, lateral view. A. Helicarion cuvieri, AM C443929. B. Helicarion cuvieri, BMNH 197780 (S of Vitrina verrauxii). C. Helicarion mastersi, AM C101139 (H). D. Helicarion mastersi, AM C101138 (PRH of H. mastersi callidus). E. Mysticarion insuetus, AM C113776 (S). F. Mysticarion porrectus, AM C101136 (PRH). G. Mysticarion hyalina, BMNH 1983075 (H). H. Parmavitrina planilabris, AM C103630. I. Peloparion helenae, AM C101142 (H). J. Brevisentis jacksoniensis, BMNH not registered (S). K. Brevisentis jacksoniensis, AM C101143 (H of B. exclusus). L. Fastosarion superba, BMNH not registered (POS). Scale bars 3 mm (E–G, I–K), 5 mm (A–D, H), 10 mm (L). Photographs by H. Barlow (A, C–D, G–H, L), D. Beechey (E, J), W. Ponder (B, F, I, K). Abbreviations: H, holotype; POS, possible syntype; PRH, probable holotype; S, syntype.

FIGURE 9. Shells, ventral view. A. Helicarion cuvieri, AM C443929. B. Helicarion cuvieri, BMNH 197780 (S of Vitrina verrauxii). C. Helicarion mastersi, AM C101139 (H). D. Helicarion mastersi, AM C101138 (PRH of H. mastersi callidus). E. Mysticarion insuetus, AM C113776 (S). F. Mysticarion porrectus, AM C101136 (PRH). G. Mysticarion hyalina, BMNH 1983075 (H). H. Parmavitrina planilabris, AM C103630. I. Peloparion helenae, AM C101142 (H). J. Brevisentis jacksoniensis, BMNH not registered (S). K. Brevisentis jacksoniensis, AM C101143 (H of B. exclusus). L. Fastosarion superba, BMNH not registered (POS). Scale bars 3 mm (D–G, I–K), 5 mm (A–C, H), 10 mm (L). Photographs by H. Barlow (A, C–D, H–I), D. Beechey (F, K), W. Ponder (B, E, G, J, L). Abbreviations: H, holotype; POS, possible syntype; PRH, probable holotype; S, syntype.

FIGURE 12. Reproductive systems. A. Helicarion cuvieri, AM C424333. B. Helicarion mastersi, AM C334204. C. Mysticarion porrectus, AM C205296. D. Mysticarion hyalina, AM C128630. E. Parmavitrina planilabris, AM C334357. F. Peloparion helenae, AM C205295. G. Brevisentis jacksoniensis, AM C348670. H. Brevisentis jacksoniensis, AM C205293. I. Fastosarion superba, AM C425248. Scale bars 2 mm (C–D, F–H), 5 mm (A–B, E, I). Abbreviations: alb, albumen gland; bc, bursa copulatrix; c, caecum; ep, epiphallus; fl, flagellum; fov, free oviduct; her, hermaphrodite duct; m, muscle attaching penial sheath to epiphallus (only shown in E); ov, ovotestis; p, penis; pr, prostate; prm, penis retractor muscle; pt, penial sheath; ut, uterus; v, vagina; vd, vas deferens.

FIGURE 13. Penis interiors. A. Helicarion cuvieri, AM C424333. B. Helicarion mastersi, AM C334204. C. Mysticarion porrectus, AM C205296. D. Mysticarion hyalina, AM C128630. E. Parmavitrina planilabris, AM C334357. F. Peloparion helenae, AM C205295. G. Brevisentis jacksoniensis, AM C205293. H. Fastosarion superba, AM C425248. I. Stanisicarion freycineti, AM C391188. J. Stanisicarion virens, QMMO19238. K. Eungarion mcdonaldi, AM C438760. L. Parmacochlea fischeri, AM C441743. Scale bars 1 mm (A–D, F–G I, K–L), 2 mm (E, H, J). Abbreviations: c, caecum; ep, epiphallus; fl, flagellum; p, penis; pp, penial pilaster; ppu, penial pustules; prm, penis retractor muscle; pt, penial sheath; pv, penial verge; vd, vas deferens.

FIGURE 15. Radulae. SEM. A–C Helicarion mastersi, AM C334204. D–F. Mysticarion porrectus, QMMO29298. G–I. Mysticarion hyalina, AM C128630. J–L. Parmavitrina planilabris, AM C334357. M–O. Peloparion helenae, AM C205295. P–R. Brevisentis jacksoniensis, AM C205293. Scale bars 20 mm (A–I, M–R); 50 mm (J–L).