Expocystis rustica ( Pfeiffer, 1852 ), Snail

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: 66-67

publication ID

http://doi.org/ 10.11646/zootaxa.2462.1.1

persistent identifier

http://treatment.plazi.org/id/6413F378-FFD6-6A48-F28B-76FCFCC7FEA1

treatment provided by

Felipe

scientific name

Expocystis rustica ( Pfeiffer, 1852 )
status

 

Expocystis rustica ( Pfeiffer, 1852)  

Figures 17P–R View FIGURE 17 , 18H View FIGURE 18 , 19J View FIGURE 19 , 20I View FIGURE 20 , 21J View FIGURE 21 , 22D View FIGURE 22 , 23C View FIGURE 23

Helix inconspicua Forbes, 1851: 379   [non Helix inconspicua C. B. Adams, 1849   ].

Helix rustica Pfeiffer, 1852: 112   [nom. nov. for Helix inconspicua Forbes, 1851   ].

Helix impexa Reeve, 1852   : pl. 130, sp. 795 [nom. nov. for Helix inconspicua Forbes, 1851   ].

Helix villaris Reeve, 1854   : pl. 195, sp. 1375.

Helix crotali Cox, 1864: 13   [nom. nov. for Helix inconspicua Forbes, 1851   ].

Helix (Xesta) rustica: Cox, 1868: 2   , pl. 9, figs 3, 3a.

Helix   (T halassia) rustica: Brazier, 1876b: 117–118   .

Helix   (T halassia) villaris: Brazier, 1876b: 118   .

Nanina (Macrochlamys) villaris: Pfeiffer & Clessin, 1881: 44   .

Nanina   (T halassia) rustica: Pfeiffer & Clessin, 1881: 46   .

Nanina   (T halassia) impexa: Pfeiffer & Clessin, 1881: 46   .

Charopa   (T halassia) rustica: Tryon, 1886: 212   , pl. 62, figs 44–45.

Nanina   (Subg. Xesta Sect. Macrochlamys   ) villaris: Tryon, 1886   : pl. 105, pl. 35, fig. 41.

Charopa   (T halassia) rustica: Cox, 1909: 8   .

Microcystis rustica: Hedley, 1912: 260   , pl. viii, fig. 42; Odhner, 1917: 77, figs 29, 30c, 33.

Expocystis rustica: Iredale, 1937c: 4   ; Smith, 1992: 230.

Synonymy follows Iredale (1937c: 4) and Smith (1992: 230).

Material examined. Queensland, Australia: BMNH 1982243 ( H. villaris   holotype) (one shell measured, photographed), Lizard Island   ; AM C425540 (two specimens dissected, one radula examined), S of Cooktown , Mt. Cook National Park (15º30' S, 145º15' E), on ground, semi deciduous microphyll vine forest, 23 Oct. 1975, P.H. Colman GoogleMaps   .

Description. External morphology: Shell ( Figures 19J View FIGURE 19 , 20L View FIGURE 20 , 21J View FIGURE 21 ) of about 5 whorls, very light pinkishbrown; shape and sculpture as for genus. Animal white. Mantle laps and lobes as for genus. Caudal horn large; caudal foss vertical slit in tail.

Mantle cavity and digestive system: As for genus.

Genital system ( Figures 18H View FIGURE 18 , 22D View FIGURE 22 , 23C View FIGURE 23 ): As for genus. Penis moderately long; epiphallus enters penis through simple pore; penis internally covered in irregular ridges, four longitudinal penis pilasters present. Epiphallus longer than penis. Spermatophore soft capsule with firm tail pipe open at one end, tail pipe long, sculptured with longitudinal rows of tiny teeth.

Radula   ( Figure 17P–R View FIGURE 17 ): As for genus. Radular formula (30.14.1.14.30) × 100 rows.

Range and habitat. Expocystis rustica   is found from Innisfail to Cape York Peninsula, N Queensland, on the mainland and also on many islands of the Great Barrier Reef. It is found in rainforest, microphyll vine forest and under trees on or behind beaches, in leaf litter, inside rotting logs and under stones.

Remarks. The synonymy of Helix inconspicua Forbes, 1851   , H. impexa Reeve, 1852   and H. crotali Cox, 1864   with Expocystis rustica   was recognised by most early authors from Cox (1868) onwards. However, Cox (1868) incorrectly placed Pravonitor kreffti   in synonymy with Helix villaris   . Iredale (1937c) first recognised H. villaris   as a synonym of Expocystis rustica   and this was followed by Smith (1992) and Smith et al. (2002).

The anatomical details given here differ from those presented by Odhner (1917), who illustrated the penial complex. His figure and description indicate that the epiphallus is absent and that the flagellum and penis retractor muscle are both present at the junction of the penis and vas deferens. A dart sac is also described as being present. Some of these differences are, in part at least, due to misinterpretation. The structure referred to as the dart sac is actually the bursa copulatrix (see also remarks under Malandena suturalis   below). It is possible that the structure referred to as the flagellum is actually the caecum, although this interpretation assumes that Odhner omitted the actual flagellum from the drawing.

The radula   shown here also differs slightly from that figured by Odhner (1917), who shows his specimen as having unicuspid marginal teeth. However, in his written description of the radula, Odhner   states that the secondary cusp of the marginal teeth is ‘rather reduced in size and rather remote from the tooth end’ ( Odhner 1917: 81), implying that there is a small secondary cusp present. A small secondary cusp was present in the radula   examined in the current study.

It is possible that Odhner’s (1917) specimen was misidentified, but no shell was figured and Odhner’s material was not examined, so this cannot be confirmed.

AM

Australian Museum

Kingdom

Animalia

Phylum

Mollusca

Class

Gastropoda

Order

Stylommatophora

Family

Helicarionidae

Genus

Expocystis

Loc

Expocystis rustica ( Pfeiffer, 1852 )

Hyman, Isabel T. & Ponder, Winston F. 2010
2010
Loc

Expocystis rustica: Iredale, 1937c: 4

Smith, B. J. 1992: 230
Iredale, T. 1937: 4
1937
Loc

Microcystis rustica:

Odhner, N. H. J. 1917: 77
Hedley, C. 1912: 260
1912
Loc

Charopa

Cox, J. C. 1909: 8
1909
Loc

Charopa

Tryon, G. W. 1886: 212
1886
Loc

Nanina (Macrochlamys) villaris:

Pfeiffer, L. & Clessin, S. 1881: 44
1881
Loc

Nanina

Pfeiffer, L. & Clessin, S. 1881: 46
1881
Loc

Nanina

Pfeiffer, L. & Clessin, S. 1881: 46
1881
Loc

Helix

Brazier, J. 1876: 118
1876
Loc

Helix

Brazier, J. 1876: 118
1876
Loc

Helix (Xesta) rustica:

Cox, J. C. 1868: 2
1868
Loc

Helix crotali

Cox, J. C. 1864: 13
1864
Loc

Helix rustica

Pfeiffer, L. 1852: 112
1852
Loc

Helix inconspicua

Forbes, E. 1851: 379
1851