Aldanellidae Linsley and Kier, 1984

Kouchinsky, Artem, Bengtson, Stefan, Landing, Ed, Steiner, Michael, Vendrasco, Michael & Ziegler, Karen, 2017, Terreneuvian stratigraphy and faunas from the Anabar Uplift, Siberia, Acta Palaeontologica Polonica 62 (2), pp. 311-440 : 345-347

Family Aldanellidae Linsley and Kier, 1984 Genus Aldanella Vostokova, 1962

Type species: Aldanella attleborensis (Shaler and Foerste, 1888) ; lower Cambrian ; Hoppin Hill, Massachusetts, USA .

Remarks.—The species-level taxonomy of Aldanella is controversial. Isakar and Peel (2007) and Parkhaev and Karlova (2011) revised and compared the named species of Aldanella . The holotype of Aldanella attleborensis (Shaler and Foerste, 1888) from Avalonian eastern Massachusetts (Landing 1988: figs. 5.1, 5.5) and the available lectotype of A. kunda Öpik, 1926 from Baltica ( Isakar and Peel 2007: fig. 2E, F, J) are internal moulds, and the holotype of A. attleborensis is a fragment of one. They are less well preserved than most of the material illustrated herein and by Isakar and Peel (2007: fig. 2) from Baltica, as well as by Parkhaev and Karlova (2011) from Siberia. The Avalonian material attributed to A. attleborensis from its type area in eastern Massachusetts and from eastern Newfoundland, southern New Brunswick, and Cape Breton Island ranges from the Watsonella crosbyi Zone through Camenella baltica Zone (terminal Fortunian Stage through lower part of Cambrian

Series 2, Cambrian Stage 3). These specimens demonstrate variability in cross-sectional shape of the whorl, inclination and projection of the spire, and development of radial folds on the inner shell surface ( Bengtson and Fletcher 1983; Landing 1988, 1991, 1996, 2004; Landing et al. 1989).

This variation has suggested extensive synonymization of Aldanella attleborensis with other named Aldanella species and with Pseudoyangtzespira selindeica in reports by EL. For example, Landing (1988; also Landing et al. 1989, 2013) regarded A. kunda as a junior synonym of A. attleborensis , which was supported by Isakar and Peel (2007) and maintained by Parkhaev and Karlova (2011). Aldanella operosa Missarzhevsky in Rozanov and Missarzhevsky, 1966 occurs through the Tommotian into the lower Atdabanian stages of the Siberian Platform. Given the better preservation of the Siberian material, recognition of such species of Aldanella from Siberia as A. attleborensis , A. crassa , A. sibirica , A. golubevi , A. utchurica , and A. operosa by Parkhaev and Karlova (2011) is maintained in this report.

Aldanella crassa is probably the oldest appearing, named species of Aldanella in Siberia (Missarzhevsky 1989;

Parkhaev and Karlova 2011; Parkhaev et al. 2011). In the Anabar Uplift, A. crassa occurs at the base of the rising excursion Iʹ, whereas A. attleborensis appears a few meters above, and its lower range probably overlaps with the upper range of A. crassa (Parkhaev and Karlova 2011) . The oldest Aldanella crassa and A. attleborensis are thus older than the lowest known Watsonella crosbyi from Siberia. In Avalonia, A. attleborensis co-occur with W.crosbyi from the base of the Watsonella crosbyi Zone (Landing et al. 2013). The presence of Aldanella in Mongolia is questionable (see faunal lists in Esakova and Zhegallo 1996). Reported from the Terreneuvian Stage of Baltica (Moczydłowska 1991; Gubanov 1998, 2002; Mens and Isakar 1999; Isakar and Peel 2007), A. kunda (Öpik, 1926) from Estonia was synonomised with A. attleborensis , whereas Aldanella polonica Lendzion, 1977 , from Poland has been tentatively synonomized with A. crassa by Parkhaev and Karlova (2011). Aldanella attleborensis also occurs in the Dahai Member of Yunnan on the Yangtze Platform and the Yanjiahe Formation of Hubei where it has beed reported as Aldanella yanjiaheensis and co-occurs with Watsonella crosbyi ( Chen 1984; Steiner et al. 2007). Pelagiella lorenzi Kobayashi, 1939 from the Upper Dolomite Member of the Soltanieh Formation of the Valiabad section of the Elburz Mountains of Iran (Hamdi 1989, 1995; Hamdi et al. 1989) was assigned by Parkhaev and Karlova (2011) to A. crassa but is somewhat less coiled and has apparently more transversely extended aperture being also similar to Pseudoyangtzespira selindeica (Fig. 17).