A small fossil insect with scales on the wings and body was identified as a representative of Aphiesmenoptera from Burmese amber. The species is introduced here as Tarachocelis microlepidopterella (†). The insect is described in detail, and photos and line drawings are provided for wing venation, head, mouthparts, scales, legs and abdomen. All characters shared with primitive Lepidoptera and Trichoptera are symplesiomorphies or groundplan traits of Amphiesmenoptera. In addition, the Burmese fossil has a number of remarkable autapomorphies, giving it an appearance that deviates clearly from known families of Lepidoptera and Trichoptera. The species, representing a family of its own, Tarachocelidae, is considered a separate and unique taxon in the stem-group of Amphiesmenoptera and is provisionally placed as Amphiesmenoptera incertae sedis.*

*NB: See Note Added in Proof (Section 4).

Although Banffia constricta was first described in 1911, the affinities of this soft-bodied fossil animal have remained unclear. Banffia is redescribed here, on the basis of over 300 specimens. Banffia has a bipartite body measuring up to 10 cm in length. The entire body is axially twisted along a spiral, clockwise as seen from the front. The anterior section consists of two fused carapace-like units with a prominent crown-like structure at the anterior end surrounding the mouth. This crown-like structure is composed of three concentric circlets. A single antenniform outgrowth lies posterior to the mouth. The posterior section of Banffia is composed of 40 to 50 lightly sclerotised segments. The anus is terminal, and situated in a caudal notch. The gut is straight. Simple serially repeated structures along the gut may represent metameric mid-gut diverticulae. Banffia is considered to have been an epibenthic gregarious animal and possibly a deposit-feeder.

Banffia is putatively classified as an end-member of the phylum Vetulicolia, in a new class, the Banffozoa. If the vetulicolids represent a stem-group deuterostome, the absence of gills and a possible endostyle in Banffia is problematic. The presence of mid-gut diverticulae in Banffia may represent a link with the protostomes.