Vertebrate microremains from the late Silurian of Arisaig, Nova Scotia, Canada

Abstract

Rare scales of agnathan thelodonts Paralogania ludlowiensis and Thelodus sp. cf. T. parvidens , or alternatively Thelodus macintoshi , and acanthodian fishes Nostolepis striata , Gomphonchus sp., Gomphonchoporus sp. aff. G. hoppei , and Machaeraporus stonehousensis (Legault) n. gen., plus acanthodian fin spines, teeth and tooth whorls have been identified from the upper Moydart and Stonehouse formations near Arisaig, Nova Scotia. The assemblage agrees well with the late Silurian (uppermost Ludlow–Přídolí) age assigned to these strata based on invertebrate assemblages, and the vertebrate taxa show affinity with British and Baltic faunas of this age. All vertebrate-bearing strata were deposited in various positions off the western shores of the Avalonia terrane during or after its collision with Laurentia.