Landouria epiplatia (Möllendorff, 1897)

Figs 17, 26–28, 31, 55; Tables 3–4

Plectotropis epiplatia Möllendorff, 1897: 67 (“ Java ”; more exactly (Zilch 1966): “W-Java: Djampang (2000′)”).

Plectotropis trichotrochium Möllendorff, 1897: 67 (“ Java ”, more exactly (Zilch 1966): “W-Java: Djampang (2000′), s. Susabuni [sic]”). Syn. nov.

Landouria epiplatia – van Benthem Jutting 1950: 466, fig. 82. — Zilch 1966: 293, pl. 7, fig. 2. Landouria rotatoria – van Benthem Jutting 1950: 461 (in part). — Zilch 1966: 294, pl. 7, fig. 6 (in part). (not Pfeiffer, 1842)

Diagnosis

Landouria epiplatia is characterized by a brownish, sharply keeled, almost disc-like shell with an only slightly elevated spire and a very wide umbilicus.

Material examined

Type material

INDONESIA – West Java • lectotype of Plectotropis epiplatia (designated by Zilch 1966); Jampang; 7°03′ S, 106°48′ E; ca 600 m a.s.l.; SMF 8909 • 1 paralectotype of Plectotropis epiplatia; same data as for preceding; SMF 8910 • lectotype of Plectotropis trichotrochium; same data as for preceding; SMF 8918 .

Other material

INDONESIA • 1 spec.; Java; ZMB 47682. – West Java • 4 spec.; 5 km from Palabuhan Ratu Bay; 7°00′ S, 106°35′ E; SMF 96542 • 2 spec.; Jampang; 7°03′ S, 106°48′ E; ca 600 m a.s.l.; SMF 8911 • 2 spec. (vouchers for van Benthem Jutting 1950); Sukabumi; 6°55′ S, 106°55′ E; ZMA 407610 • 1 spec. (det. anat.; see remarks); Bogor, Gunung Gede; 6°46′ S, 106°59′ E; ZMH 79946 .

Description

SHELL (Figs 26–28; Tables 3–4). Almost disc-like, with 5.25–6.25 hardly convex whorls; protoconch almost smooth; teleoconch with irregular wrinkles; apical side with indistinct incised spiral lines, umbilical side with more distinct spiral lines; scaly processes sparse, mainly at periphery; tuberculate around umbilicus; brownish-corneous; body whorl sharply keeled; aperture rounded rhombic; upper insertion of peristome slightly descending; peristome expanded, slightly reflexed and slightly thickened; umbilicus almost concentric, very wide, comprising 30–43% of shell diameter, hardly obscured by columellar edge.

GENITALIA (Figs 17, 31; Table 4). Atrium short; penis very long, with a small bulge at proximal end containing a short penis papilla; without penis coecum; membranaceous sheath around distal part of penis connected with epiphallus by tissue; penial retractor runs from diaphragm to proximal part of cylindrical epiphallus; flagellum very long, broadest in its middle part, without node, tapering towards its proximal end; vas deferens narrow and long; vagina long; oviduct short, broad; peduncle of bursa copulatrix subdivided into a broader, abruptly tapering distal part and a narrower, longer proximal part. Right ommatophoral retractor runs between penis and vagina.

Remarks

Landouria epiplatia was described from Jampang in West Java. However, there are several places called Jampang in West Java, two among them being more important ones: Jampang Kulon and Jampang Tengah in Sukabumi Regency. Jampang Kulon is at ca 300 m a.s.l., Jampang Tengah is at ca 500 m a.s.l. and closer to Sukabumi, the locality given by van Benthem Jutting (1950). Thus, we suppose that Jampang Tengah is the type locality.

Plectotropis trichotrochium Möllendorff, 1897 (Fig. 27) was synonymized with L. rotatoria by van Benthem Jutting (1950) and Zilch (1966). However, in contrast to L. rotatoria, the spire of the single specimen on which P. trichotrochium was based is hardly elevated. We suppose that the holotype of P. trichotrochium is a subadult specimen of L. epiplatia that formed a slightly expanded peristome at a premature stage. The specimen is furthermore characterized by stronger radial wrinkles and more distinct incised spiral lines than is usual in L. epiplatia . Nevertheless, its occurrence at the type locality of L. epiplatia also indicates that it is an aberrant specimen of that species. As first revisers (ICZN 1999: Art. 24), we determine precedence of the name Plectotropis epiplatia Möllendorff, 1897 over Plectotropis trichotrochium Möllendorff, 1897 .

The description of the genitalia is based on a single subadult specimen from Gunung Gede (ZMH 79946; Figs 17, 31), which differs from typical L. epiplatia in the slightly tighter coiled, more elevated spire. The available material is insufficient to decide whether this specimen falls within the variability of L. epiplatia or represents a distinct species.

Distribution

Landouria epiplatia is known from the northern part of Sukabumi Regency in West Java and its range might extend to Gunung Gede (Fig. 55).