Diplommatina diplostoma Rensch, 1931

Hausdorf, Bernhard, 2017, Revision of the Diplommatinidae (Gastropoda: Cyclophoroidea) from Java, Zootaxa 4312 (2), pp. 201-245 : 215-216

Diplommatina diplostoma Rensch, 1931

( Figs 16 , 27–28 ; Table 1)

Diplommatina ( Metadiancta ?) diplostoma RenSch, 1931: 389 , fig. 14 (Bali: Batoeriti [800 m]).

Diplommatina duplicilabra Van Benthem Jutting, 1948: 597 , fig. 54 (Kawah Idjen Game ReSerVe, 1600–1700 m).

Diplommatina diplostoma — Vermeulen & Whitten 1998: 49, 138, fig. 26.

Diplommatina sulcicollis —Heryanto 2008: 362 (partly, not Möllendorff 1897). Heryanto 2009: 332 (partly, not Möllendorff 1897).

Palaina gedeana —Heryanto 2008: 362 (partly, non Möllendorff, 1897). Heryanto 2009: 332 (partly, non Möllendorff, 1897).

Diagnosis. Diplommatina diplostoma is characterized by its cylindrical-ovoid shell with an at least partly covered umbilicus.

Shell ( Fig. 27–28 ; Table 1). Dextral; cylindrical-ovoid with early whorls conical and a slightly narrowed last whorl; with 5.25–6.5 whorls separated by a deep suture; protoconch smooth; teleoconch with slightly oblique ribs (24–87 on the penultimate whorl; fewer on the last whorl); without discernible spiral striae between the ribs; whitish-light corneous; subtranslucent; last whorl rounded, without a distinct constriction; aperture almost circular; upper insertion of the peristome ascending towards aperture; insertions of the peristome connected by a distinct callus; peristome expanded, thickened, doubled; aperture with a low columellar lamella; with a rudiment of a parietal lamella and a spiral palatal fold in the middle of the whorl ventrolaterally left inside the last whorl; with a radial palatal fold ventrally near the suture; umbilicus partly covered by the reflection of the inner peristome or closed; operculum thin, corneous, circular, paucispiral. Shell height 2.6–4.1 mm, shell diameter 1.6–2.7 mm.

Remarks. We follow Vermeulen & Whitten (1998) in considering D. duplicilabra van Benthem Jutting, 1948 from East Java conspecific with D. diplostoma Rensch, 1931 from Bali.

So far D. diplostoma has been found on Mt. Ciremai in West Java, near Mt. Argopuro and on Mt. Ijen in East Java, and on Bali. The populations from the different regions differ in shell height (2.6–3.0 mm in West Java, 2.8– 3.3 mm in East Java and 3.7–4.5 mm in Bali) and ribbing (68–87 ribs on the penultimate whorl in West Java, 47–64 in East Java and 26–35 in Bali). Moreover, the peristomes are only slightly expanded and closer together in the populations from West Java than in the eastern populations and the umbilicus is usually only partly covered in the populations from West Java whereas it is always closed in the eastern populations. If these differences between populations from different regions persist when more material becomes available, the populations from West Java, East Java and Bali may be classified as different subspecies.

Habitat. In leaf litter in humid forests on calcareous and volcanic soils at 800–1950 m a.s.l.

Type material. Indonesia, Java, East Java: Banyuwangi, below Ijen Crater , 1600–1700 m a.s.l., 8°05'S 114°14'E (holotype of D. duplicilabra ZMA 135940 ).

Other material. Indonesia, Java, West Java: Majalengka, Argamukti, Mt. Ciremai National Park, 6°54'S 108°22'E (MZB 18898/1, voucher to Heryanto 2008, 2009 [as D. sulcicollis ]); Majalengka, Argamukti, Mt. Ciremai National Park, 1735 m, 6°54'S 108°22'E (MZB 18895/1, 18896/37, vouchers to Heryanto 2008 [as P. gedeana ]); Kuningan, Palutungan, 1950 m a.s.l., 06°55'15"S 108°24'40"E (MZB 18897/1).—East Java: Bremi near Mt. Argopuro, 1200 m a.s.l., 7°58'S 113°29'E (JV 4017/1); Banyuwangi, Mt. Ijen, Merapi Ungup-ungup, 1850 m a.s.l., 8°05'S 114°14'E (van Benthem Jutting 1948).

Distribution ( Fig. 16 ). Diplommatina diplostoma is known from a few, scattered localities in West and East Java and from Bali ( Rensch 1931; Vermeulen & Whitten 1998).

Figures

FIGURES 15 – 19. DiStribution of Diplommatinidae in JaVa. 15. Diplommatina baliana Fulton, 1899. 16. Diplommatina diplostoma RenSch, 1931, Diplommatina nevilli (CroSSe, 1879) and Diplommatina canaliculata Möllendorff, 1887. 17. Diplommatina auriculata Möllendorff, 1897. 18. Palaina gedeana Möllendorff, 1897, Palaina nubigena Möllendorff, 1897 and Arinia yanseni n. sp. 19. Opisthostoma javanicum Van Benthem Jutting, 1932, Opisthostoma uranoscopium Van Benthem Jutting, 1932 and Opisthostoma sp.

FIGURES 26 – 28. Diplommatina Spp. from JaVa. 26. Diplommatina heryantoi n. sp., Central JaVa: Mt. Slamet (holotype MZB 15438). 27. Diplommatina diplostoma RenSch, 1931, WeSt JaVa: Majalengka, Argamukti, Mt. Ciremai National Park (MZB 18895). 28. Diplommatina diplostoma RenSch, 1931, EaSt JaVa: Banyuwangi, Ijen Crater (holotype of D. duplicilabra ZMA 135940). Scale bar = 1.0 mm.