Heterogen longispira (Smith, 1886)

Saito, Takumi & Kagawa, Osamu, 2020, New insights from museum specimens: a case of Viviparidae (Caenogastropoda: Mollusca) in Iwakawa's collection preserved in the National Museum of Nature and Science, Tokyo, Biodiversity Data Journal 8, pp. 52233-52233 : 52233

Heterogen longispira (Smith, 1886)

Paludina ingallsiana - Kobelt 1879: 124, pl. 10, figs. 15-18, pl. 11, fig. 2 [part; pl. 10, figs. 15-16 and 18 seemingly have the intermediate morphology between H. japonica and H. longispira , see discussion]; Tanba et al. 1883: 368; Iwakawa 1895: 412 [part]; Iwakawa 1897a: 86 [part]; Iwakawa 1897b: 5 [part].

Paludina longispira Smith 1886: 57-58. Type locality: Lake Biwa. (original description).

Viviparus sclateri - Pilsbry 1902: 118, pl.9, fig. 4 [part; see discussion]; Hirase 1909: 45 [part?]; Hirase 1910: 15 [part?]; Lake Biwa fisheries experimental station 1915: 30, fig. 13; Iwakawa 1919: 72 [part].

Vivipara sclateri - Kobelt 1909: 102, pl. 16, figs. 7, 9, pl. 17, figs. 1-5. [part; pl. 16, fig. 9 and pl. 17, figs. 3, 5 seemingly have the intermediate morphology between H. japonica and H. longispira , see discussion]; Annandale 1916: 46 [part]; Kawamura 1918: 358, fig. 441 [part?].

Heterogen turris Annandale 1921: 400, figs. 1-2. Type locality: Lake Biwa. (original description).

Viviparus (Heterogen) turris - Hirase 1927: 1381, fig. 2655.

Viviparus (Heterogen) longispira - Prashad 1928: 172, pl. 19, fig. 7.

Heterogen longispira - Kuroda 1947b: 3.

Viviparus (Heterogen) turis - Okada and Kurasawa 1950: 153, figs. 10-11, and 14, (in text), pl. 2, figs. 7-8, pl. 3, figs. 9-10, pl. 4, figs. a"-g". [sic].

Viviparus longispira - Hirase and Taki 1951: pl. 77, fig. 10.

Cipangopaludina (Heterogen) longispira - Kuroda and Habe 1965a: 48, fig. 151.

Materials

Type status: Other material. Occurrence: occurrenceDetails: https://www.gbif.org/occurrence/2864965305; catalogNumber: 2964L ex.NSMT-Mo 2964 ; recordNumber: 2964 in Iwakawa 1919; individualCount: 1; lifeStage: adult; preparations: shell (dried); previousIdentifications: Viviparussclateri (Frauenfeld, 1865) in Tomotaro Iwakakawa. 1919. Catalogue of Japanese Mollusca in the Natural history department, Tokyo Imperial Museum, the tokyo Imperial Museum, Tokyo, Japan, p. 72.; occurrenceID: paper:SK2020:2964L; Taxon: scientificName: Heterogenlongispira (Smith, 1886); kingdom: Animalia; phylum: Mollusca; family: Viviparidae; vernacularName: Naga-tanishi (in Japanese name); Location: country: Japan; stateProvince: Shiga; locality: Lake Biwa ; verbatimLocality: Biwa-ko (in Japanese) [Lake Biwa]; Identification: identifiedBy: Takumi Saito; dateIdentified: 2020-02-03/04; Event: year: before 1919; Record Level: language: Japanese; bibliographicCitation: Tomotaro Iwakakawa. 1919. Catalogue of Japanese Mollusca in the Natural history department, Tokyo Imperial Museum, the tokyo Imperial Museum, Tokyo, Japan, p. 72.; institutionCode: NSMT; collectionCode: Mo; basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: occurrenceDetails: https://www.gbif.org/occurrence/2864965303; catalogNumber: 2966L ex.NSMT-Mo 2966 ; recordNumber: 2966 in Iwakawa 1919; individualCount: 2; lifeStage: 1adult 1 young; preparations: shell (dried); previousIdentifications: Viviparussclateri (Frauenfeld, 1865) in Tomotaro Iwakakawa. 1919. Catalogue of Japanese Mollusca in the Natural history department, Tokyo Imperial Museum, the tokyo Imperial Museum, Tokyo, Japan, p. 72.; occurrenceID: paper:SK2020:2966L; Taxon: scientificName: Heterogenlongispira (Smith, 1886); kingdom: Animalia; phylum: Mollusca; family: Viviparidae; vernacularName: Naga-tanishi (in Japanese name); Location: country: Japan; stateProvince: Shiga; locality: Hikone, Hikone City ; verbatimLocality: Hikone (in Japanese) [Hikone, Hikone City]; Identification: identifiedBy: Takumi Saito; dateIdentified: 2020-02-03/04; Event: year: before 1919; Record Level: language: Japanese; bibliographicCitation: Tomotaro Iwakakawa. 1919. Catalogue of Japanese Mollusca in the Natural history department, Tokyo Imperial Museum, the tokyo Imperial Museum, Tokyo, Japan, p. 72.; institutionCode: NSMT; collectionCode: Mo; basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: occurrenceDetails: https://www.gbif.org/occurrence/2864965313; catalogNumber: 2969L ex.NSMT-Mo 2969 ; recordNumber: 2969 in Iwakawa 1919; individualCount: 6; lifeStage: adults; preparations: shell (dried); previousIdentifications: Viviparussclateri (Frauenfeld, 1865) in Tomotaro Iwakakawa. 1919. Catalogue of Japanese Mollusca in the Natural history department, Tokyo Imperial Museum, the tokyo Imperial Museum, Tokyo, Japan, p. 72.; occurrenceID: paper:SK2020:2969L; Taxon: scientificName: Heterogenlongispira (Smith, 1886); kingdom: Animalia; phylum: Mollusca; family: Viviparidae; vernacularName: Naga-tanishi (in Japanese name); Location: country: Japan; stateProvince: Shiga; locality: Zeze, Ohtsu City ; verbatimLocality: Zeze (in Japanese) [Zeze, Ohtsu City]; Identification: identifiedBy: Takumi Saito; dateIdentified: 2020-02-03/04; identificationRemarks: Some specimens are presumed to be hybrid species between H.longispira and H.japonica (see taxon discussion section).; Event: year: before 1919; Record Level: language: Japanese; bibliographicCitation: Tomotaro Iwakakawa. 1919. Catalogue of Japanese Mollusca in the Natural history department, Tokyo Imperial Museum, the tokyo Imperial Museum, Tokyo, Japan, p. 72.; institutionCode: NSMT; collectionCode: Mo; basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: occurrenceDetails: https://www.gbif.org/occurrence/2864965314; catalogNumber: 2970L ex.NSMT-Mo 2970 ; recordNumber: 2970 in Iwakawa 1919; individualCount: 15; lifeStage: 11 adults 4 juveniles; preparations: shell (dried); previousIdentifications: Viviparussclateri (Frauenfeld, 1865) in Tomotaro Iwakakawa. 1919. Catalogue of Japanese Mollusca in the Natural history department, Tokyo Imperial Museum, the tokyo Imperial Museum, Tokyo, Japan, p. 72.; occurrenceID: paper:SK2020:2970L; Taxon: scientificName: Heterogenlongispira (Smith, 1886); kingdom: Animalia; phylum: Mollusca; family: Viviparidae; vernacularName: Naga-tanishi (in Japanese name); Location: country: Japan; stateProvince: Shiga; locality: Seta River ; verbatimLocality: Seta-gawa (in Japanese) [the Seta River]; Identification: identifiedBy: Takumi Saito; dateIdentified: 2020-02-03/04; identificationRemarks: Some specimens are presumed to be hybrid species between H.longispira and H.japonica (see taxon discussion section).; Event: year: before 1919; Record Level: language: Japanese; bibliographicCitation: Tomotaro Iwakakawa. 1919. Catalogue of Japanese Mollusca in the Natural history department, Tokyo Imperial Museum, the tokyo Imperial Museum, Tokyo, Japan, p. 72.; institutionCode: NSMT; collectionCode: Mo; basisOfRecord: PreservedSpecimen

Diagnosis

Adult shell moderately large and very thick; shell shape subconical. Adult shell dark brown or greenish-brown sometimes covered with attachments; shell surface often having growth lines and several spiral ridges. Suture deeper than in any other viviparid from Japan; whorls strongly shouldered. Young shell small and relatively thin, but not fragile; shell shape pyramidal to subconical. Young shell bright olive; shell surface quite glossy having strong spiral ridges on upper part of spire. The shell size upon birth is larger than that of any other viviparid gastropod in Japan.

Taxon discussion

Heterogen longspira can be distinguished from other Japanese Viviparidae by criteria based on the illustrations and information from literature (Suppl. material 1). In particular, the juvenile and young shell have strong spiral ridges on the upper part of each whorl, this feature having crucial diagnostic value ( Okada and Kurasawa 1950, Hirano et al. 2019b). Furthermore, the shell size of the juvenile upon birth is larger than that of any other viviparid gastropods in Japan.

Firstly, H. longispira is easily distinguished from Cipangopaludina species/subspecies in Japan, based on the pyramidal shell shape, the higher spire, the narrower spire angle and the linear body whorl ( Kihira et al. 2009; Fig. 4 ).

Besides, adult Sinotaia quadrata histrica is generally smaller than H. longispira . There is a high morphological diversity in the shell shape of S. q. histrica ( Kihira et al. 2009); however, the body whorl and the spire whorl are much more rounded and arched than those of H. longispira . In addition, the suture of S. q. histrica is shallower than that of H. longispira . The upper whorl of adult S. q. histrica does not have the pronounced spiral ridges. Moreover, the shell colour of S. q. histrica is brighter than that in H. longispira and often has a yellowish colour.

Both adult H. longispira and Heterogen sp. have the spiral ridges on the upper whorl ( Hirano et al. 2019b), but the ridges of H. longispira are stronger than Heterogen sp. In addition, the shell shape of Heterogen sp. is indistinguishable from that of H. japonica and then there are some differences in the shell shape between H. longispira and Heterogen sp. ( Hirano et al. 2019b; refer to taxon discussion on the section of H. japonica for the difference).

Notes

Heterogen longispira was identified in four of the 11 lots examined, which were all from Lake Biwa drainage only (Figs 3 , 4 ). Lots Mo2969 and Mo2970 contained non-typical H. longispira with an intermediate morphology to H. japonica and H. longispira (e.g. Fig. 3 c and g-k). The shell shapes of these specimens tend to be slightly more similar to H. japonica ; however, they have several distinctive morphological features of H. longispira , namely, the pronounced spiral ridges, the shouldered whorl, the deep suture, the strong basal angle and the high spire. Therefore these specimens were tentatively identified as H. longispira here (see also discussion).

Based on the previous taxonomy ( Kuroda 1929), synonymy included the species-group name turris (and incorrectsubsequentspellings) in addition to the species-group name longispira . For species-group names Paludina ingallsiana and sclateri , refer to the discussion.

Figures

Figure 3. Shells of Heterogen japonica (Martens, 1861), H. longispira (Smith, 1886), and the intermediate morphology between the two species stored at the National Museum of Nature and Science, Tokyo, which were treated as Viviparus sclateri (Frauenfeld, 1865) in Iwakawa's catalogue (1919). a-b: H. japonica in 2969 J from Otsu City, Shiga Pref. c-d: non-typical H. longispira in 2969 L from Otsu City, Shiga Pref. e: typical H. longispira in 2969 L from Otsu City, Shiga Pref. f: subadult H. japonica in 2969 J from Otsu City, Shiga Pref. g-j: non-typical and intermediate H. longispira in 2970 L from the Seta River, Shiga Pref. K: typical H. longispira in 2970 L from the Seta River, Shiga Pref. l: a juvenile shell of H. japonica in 2970 J from the Seta River, Shiga Pref. m: a typical juvenile shell of H. longispira in 2970 L from the Seta River, Shiga Pref.

Figure 4. Representative shells of Heterogen longispira (Smith, 1886) from Japan, deposited in the collection of the National Museum of Nature and Science, Tokyo, which were treated as Viviparus sclateri (Frauenfeld, 1865) in Iwakawa (1919). a: 2964 L from Lake Biwa, Shiga Pref. b: 2966 L from Hikone City, Shiga Pref.