Data from: Late Ordovician and Early Silurian virgianid and stricklandioid brachiopods from North Greenland: Implications for a warm-water faunal province

An unusually rich and diverse suite of virgianid brachiopods, hitherto
poorly known, are systematically described here for the first time from
the Ordovician–Silurian boundary interval (late Katian–Aeronian) of North
Greenland. The Late Ordovician virgianids comprise typical taxa of the
warm-water Tcherskidium fauna (e.g. Tcherskidium tenuicostatum,
Proconchidium schleyi, Holorhynchus giganteus, and Deloprosopus dawesi sp.
nov.). Among the early Silurian taxa, Virgiana hursti sp. nov. occurs as
abundant shell beds, similar to other congeneric species in Laurentia, but
has somewhat larger internal skeletal structures, albeit not as
extravagantly developed as in the late Katian virgianids; Boraeloides
balderi gen. et sp. nov. shows extreme thickening of shell wall and
internal structures, approaching the extravagant calcification of Katian
virgianids. The highly distinct mid-Aeronian stricklandioid brachiopod
genus, Kulumbella, characterized by a shell with criss-cross (divaricate)
ribbing, also occurs in North Greenland, represented by K. heimdalli sp.
nov., which has the largest and most strongly biconvex shells for the
genus. Palaeogeographically, the Late Ordovician virgianid fauna of
Laurentia was highly distinct, confined to the low–mid tropical latitudes
north of the palaeoequator. In comparison, the early Silurian (Rhuddanian)
Virgiana and some related taxa in Laurentia spanned the tropics of both
hemispheres, forming extensive shell beds in carbonate basins, although
Borealis and Borealoides gen. nov. remained confined largely to the
northern hemisphere, suggesting a certain level of provincialism extending
into the earliest Silurian. The unusual abundance and richness of the
virgianid faunas in North Greenland is likely explained by a
palaeoecological preference for warm-water carbonate settings.