Dacryomya Explained

Dacryomya, or the pointed nutclam is an extinct genus of small-sized (approximately 1cm (00inches) long) saltwater clams, marine bivalve molluscs in the nutclam family Nuculanidae. The size and shape of the shells of species in this genus are reminiscent of broad apple pips.

Distribution

Dacryomya lived during the Lower and Middle Jurassic, possibly throughout the Tethys Faunal Province.^[1] Fossils of D. lacryma are known from the very late Lower Jurassic (Toarcian) of France (Causes, 44.3° N, 3.3° E);^[2] the early middle Middle Jurassic (Bajocian) of Germany (Sengenthal); and the very late Middle Jurassic (Callovian) of India (the Gadhada Sandstone Member and the Chari Formation, 23.5° N, 70.5° E).^[3]

Habitat

The fossil locations cited were open shallow subtidal areas,^[2] where this mollusc lived as a facultatively mobile infaunal deposit feeder-suspension feeder.^[4]

Other views

These additional views of the two shells of Dacromya lacryma give more information about the overall shape of the shell in that species:

Further reading

• Karapunar, B.; Werner, W.; Fürsich, F. T.; Nützel, A. (2020). Taxonomy and palaeoecology of the Early Jurassic (Pliensbachian) bivalves from Buttenheim, Franconia (Southern Germany). Palaeontographica, Abteilung A. 318(1–4): 1–127., available online at https://doi.org/10.1127/pala/2020/0098

Notes and References

1. W. Kiessling, D. K. Pandey, M. Schemm-Gregory, H. Mewis, and M. Aberhan. 2011. "Marine benthic invertebrates from the Upper Jurassic of northern Ethiopia and their biogeographic affinities". Journal of African Earth Sciences 59:195–214
2. Fürsich, F.T., R. Berndt, T. Scheuer and M. Gahr. Comparative ecological analysis of Toarcian (Lower Jurassic) benthic faunas from southern France and east-central Spain. Lethaia 34:169–199. 2001 http://paleodb.org/cgi-bin/bridge.pl?a=displayCollResults&taxon_no=170000&max_interval=Jurassic&country=France&is_real_user=1&basic=yes&type=view&match_subgenera=1
3. http://paleodb.org/cgi-bin/bridge.pl?a=displayCollResults&taxon_no=170000&max_interval=Jurassic&country=India&is_real_user=1&basic=yes&type=view&match_subgenera=1 F.T. Fürsich. 2006. Unpublished data from Kachchh
4. http://paleodb.org/cgi-bin/bridge.pl?a=basicTaxonInfo&taxon_no=169999 Paleobiology Database