Three new species of fossil Anisoptera [dragonflies) are reported from Tiffanian (Late Palaeocene) sediments of the Paskapoo Formation, near Red Deer, Alberta, Canada. The three species are all assigned to the new genus Altoaeschna, which is classified in the subfamily Gomphaeschninae.Phylogenetic analysis of gomphaeschnine wing venation suggests that the subfamily is paraphyletic, with derived gomphaeschnines such as Boyeria and Linaeschna more closely related to the Brachytroninae and Aeshninae than are other gomphaeschnines. One of the most primitive gomphaeschnines, and the oldest fossil form, is the Jurassic Morbaeschna. Parallelism, convergence and reversal in the evolution of features of the wing venation is common.The new genus Alloaeschna is at about the same evolutionary grade as the old-world genus Oligoaeschna and the new-world genus Gomphaeschna, and is one of the more primitive known members of the Gomphaeschninae. The new species are the first recorded Palaeocene gomphaeschnines and the oldest known gomphaeschnines from the Americas.Several extant genera have fossil representatives on continents different from those on which they now survive, suggesting repeated crossing of land bridges and/or widespread ancestral species prior to the separation of the continents, and subsequent extinction leading to present relict distributions

New Paleocene orthopteroid taxa from the Paskapoo Formation are described. All are represented by adult wings. Albertoilus cervirufi n.gen., n.sp. (superfamily Hagloidea, family Prophalangopsidae, subfamily Prophalangopsinae) is a descendant from the same stock as the Jurassic Aboilus. Phasmomimella paskapoensis n.gen., n.sp. and Phasmomimula enigma n.gen., n.sp. (superfamily Phasmomimoidea, family Phasmomimidae) extend the known existence of the family from the Early Cretaceous to the Paleocene; they are the most advanced and first recorded American phasmomimids. Pseudotettigoniinae n.subfam. (superfamily Tettigonioidea, family Tettigoniidae) is proposed to include the primitive genera Pseudotettigonia Zeuner (type genus), Arctolocusta Zeuner, and Nymphomorpha Henriksen. Genus and species incertae sedis, the oldest recorded tettigonioid, with primitive venation, is assigned to the new subfamily. Promastacidae n.fam. (superfamily Eumastacoidea) is erected to include the early Tertiary type genus Promastax Handlirsch and the oldest and most primitive eumastacoid, Promastacoides albertae n.gen., n.sp. The closest relatives of the new family are the Tertiary and Recent Eruciidae.

Two localities in central Alberta yielding insects of Paleocene age are described. About half of the 176 specimens obtained are coleopteran larvae; many of the adults and larvae are members of aquatic groups.

Three new species of fossil Tipulidae are described. Pseudolimnophila speirsae n. sp. and Limnophila marklae n. sp. (subfamily Limoniinae, tribe Hexatomini) are represented by adults; Tipula tubifera n. sp. (subfamily Tipulinae, tribe Tipulini) is represented by a pupa. Six other pupae belong to the subfamily Tipulinae.

Fossil oribatid mites were recovered from the Paskapoo Formation exposed along the Red Deer River valley near Blackfalds (fossil insect site 1, 12UUP 171 030). The fossils are Late Paleocene (approximately middle Tiffanian) in age (Fox in press). Other adult and immature fossil insects collected from the same locality reported by Mitchell and Wighton (1979) inhabited a mixed forested environment with associated low-energy, shallow, fresh water. The climate at the time of deposition is suggested by Wighton (1980, 1982) to have been warm-temperate to subtropical. The 11 adult and seven immature fossil mites (Fig. 1 specimen no. UAPC6186) are associated with an unidentified fossil insect larva and two chironomid fly pupae on the underside of a compression-impression fossil leaf of “Viburnum” cupanioidea (Newbeq) R. W. Brown (Caprifoliaceae). Most structures on the larvae are obscured, but the size (length 220–240 μm, width 140–150 μm), absence of dark pigmentation, presence of 3 pairs of legs, and general appearance closely resemble oribatid mite larvae (Fig. 2a,b). The adult specimens have several characteristics in common with the extant genus Hydrozetes. The triangular prodorsum lacks microsculpture and narrows to a pointed rostrum (Fig. 2c,d). Examination of the bothridial area in two specimens indicates that the bothridium is reduced and the sensillus is not present. The legs are monodactylous (Fig. 2d,e) and pteromorphae are absent. The notogastral margin is incomplete anteriorly and bears a round, concave area that probably represents the lenticulus. The size (length 495–520 μm, width 325–355 μm) and general habitus of the fossil mites closely resemble those of extant Hydrozetes species.