First fossil Huttoniidae (Arthropoda: Chelicerata: Araneae) in late Cretaceous Canadian amber

The first fossils of the extant New Zealand spider family Huttoniidae are described from Cretaceous (Campanian) amber from Alberta and Manitoba, Canada. The specimens are juveniles and poorly preserved, but the following combination of characters permits identification as huttoniids: general habitus, carapace without a raised cephalic region or fovea, eight eyes in two rows of four, three-clawed tarsus (with tiny median claw), elongate patella, ventral preening comb on metatarsus 3, spines absent on legs 1 and 2 but present on legs 3 and 4, and spatulate setae on anterior metatarsi. The fossils cannot be assigned reliably to the single, extant, monotypic genus Huttonia O. Pickard-Cambridge, and no new taxa are erected. The fossils extend the known geological age of Huttoniidae back approximately 80 myr and, by inference, that of their putative sister taxon Spatiatoridae back approximately 35 myr, both to prior to the K/T extinction. The relative abundance of this family in the two Canadian amber deposits is similar, which suggests the deposits sampled are from similar habitats. The disjunct distribution of the fossil and extant members of this family supports the theory of ousted relicts over mobilistic biogeography for explaining the strictly austral distributions of the extant organisms.