Tapes ezoënsis
Yokoyama 1890: 197
Meretrix ( Macrocallista ) ezoensis (Yokoyama)
Tapes
ezoensis Yokoyama
Minato and Uozumi 1951: 150
Hubertschenckia ezoensis ( Yokoyama, 1890 )
Hubertschenckia ezoensis ( Yokoyama, 1890 )
Hubertschenckia ezoensis (Yokoyama)
Takeda 1953: 85
Hubertschenckia ezoensis (Yokoyama)
Oyama et al. 1960: 188– 189
Hubertschenckia ezoensis (Yokoyama)
Hubertschenckia ezoensis (Yokoyama)
Amano and Kiel 2007: 275–277
Hubertschenckia ezoensis (Yokoyama)
New taxa, records, and data for vesicomyid bivalves from Cenozoic strata of the North Pacific region
Kiel, Steffen
Amano, Kazutaka
Goedert, James L.
Acta Palaeontologica Polonica
2023
2023-06-21
68
2
297
320
C5HZ4
(Yokoyama, 1890)
Yokoyama
1890
[862,1440,252,282]
Bivalvia
Vesicomyidae
Hubertschenckia
Animalia
Venerida
18
315
Mollusca
species
ezoensis
Fig. 13.
1890 Tapes ezoënsis sp. nov.; Yokoyama 1890: 197, pl. 25: 6–8. non 1928 Meretrix( Macrocallista) ezoensis(Yokoyama). Yokoyama 1928: 77, pl. 8: 1. 1951 Tapes(new gen.?) ezoensisYokoyama; Minato and Uozumi 1951: 150, pl. 13: 108a–c. Fig. 13. The vesicomyid bivalve Hubertschenckia ezoensis( Yokoyama, 1890), from the upper Eocene Poronai Formation in Hokkaido, Japan. A. NRM Mo 204823, very large RV; external sculpture (A 1) and hinge (A 2) views. B. NRM Mo 204821, small articulated specimen; showing ligament (B 1) and external ornament and posterior ridge (B 2). C. NRM Mo 204824, internal mold of large RV, showing anterior adductor muscle scar; view on right valve (C 1) and close-up on hinge area (C 2). D. NRM Mo 204825, large articulated specimen, mostly an internal mold; view on right valve (D 1) and left valve (D 2). E. NRM Mo 204822, hinge of LV. Table 9. Measurements (in mm) of Hubertschenckia ezoensis( Yokoyama, 1890)from the Poronai Formation; na, measurement not possible. Specimen no. Length Height Width NRM Mo 204821 55.8+ 38.8 25.5 NRM Mo 204822 85.0 44.0 na NRM Mo 204823 na 65.0 na NRM Mo 204824 90.4 52.6 na NRM Mo 204825 92.4 50.5 na 1953 Hubertschenckia ezoensis(Yokoyama); Takeda 1953: 85, pl.13: 5. 1960 Hubertschenckia ezoensis(Yokoyama); Oyama et al. 1960: 188– 189, pl. 58: 2a–d. non 1989 Hubertschenckia ezoensis(Yokoyama); Honda 1989: 79: 13, 14. 2007 Hubertschenckia ezoensis(Yokoyama); Amano and Kiel 2007: 275–277, figs. 6–12. 2007 Hubertschenckia ezoensis(Yokoyama); Amano and Jenkins 2007: fig. 2B.
2013 Hubertschenckia ezoensis(Yokoyama); Amano et al. 2013: figs. 6K–M. 2016 Hubertschenckia ezoensis(Yokoyama); Nobuhara et al. 2016: figs. 2–16. 2016 Hubertschenckia ezoensis(Yokoyama); Kiel et al. 2016: fig. 1G. 2022 Hubertschenckia ezoensis(Yokoyama); Amano et al. 2022: figs. 10.9a, k. Material.— Five large specimens ( NRMMo 204821–25) from the upper Eocene Poronai Formationin Hokkaido, Japan. Dimensions.—See Table 9. Remarks.—We illustrate several very large specimens of Hubertschenckia ezoensisto further document the characteristics of this species and their variability. The largest previously published specimen measured 74.6 mm in length Amano and Kiel 2007); the largest specimen reported here exceeds 90 mmin length. One of our specimens has a height of 65 mm. Considering the L/H ratio of ca. 1.8 known from other specimens of Hubertschenckia ezoensis, this specimen could have been almost 120 mmin length, making it the largest Eocene vesicomyid known to date. Stratigraphic and geographic range.—Upper Eocene to lower Oligocene, Hokkaido, Japan.
NRM
Japan
upper Eocene Poronai Formation
19
316
1
Hokkaido