Tanytermitidae Engel, fam. nov.

Type genus. Tanytermes Engel et al., 2007.

Included genera. Aside from the type genus, the family includes the new genus Tanytermitalis Engel & Cai, gen. nov. (vide infra).

Diagnosis. Alate with head elongate, much like the longer alate heads of some Heterotermes Froggatt, 1897 (e. g., Heterotermes paradoxus (Froggatt, 1898), H. occiduus Hill, 1927), sub-rectangular, fontanelle absent (present in Neoisoptera) (Figs 1B, 7), Y-shaped cleavage scar absent; compound eyes small, circular (Fig. 7C); ocelli absent (present in Icoisoptera); mandibles not extending beyond apex of labrum (Fig. 7D),right mandible with two sharp marginal teeth and elongate apical tooth, without subsidiary tooth (present in Archotermopsidae and Stolotermitidae) [dentition known only for Tanytermes, obscured in Tanytermitalis, vide infra]; antenna with 14–18 articles (longer in Mastotermitidae and Teletisoptera, although some Stolotermitidae with as few as 15 articles) (Fig. 7A, B). As in all termites with the exception of some basal groups like Melqartitermitidae and Mylacrotermitidae (vide supra), Tanytermitidae lack ventral cervical sclerites (observable only in Tanytermitalis). Pronotum flat (weakly saddle shaped in Hodotermitidae), either slightly narrower or broader than head. Tibial spur formula 2–3–2 or 3–3–2 (3–3– 3 in Kalotermitidae) (Fig. 7E–G); tarsi tetramerous (i. e., second tarsomere absent—second tarsomere becomes cryptic in some Teletisoptera and then wholly absent in other clades) (Fig. 7E–G); pretarsal claws simple, arolium present or absent. Wing membranes not reticulate; Sc, R, and Rs heavily pigmented, remaining longitudinal sectors lightly pigmented; forewing scale large, overlapping hind wing scale (plesiomorphy relative to Termitidae); CuP (claval fissure) terminating on posterior wing margin prior to basal cleavage suture (i. e., inside of scale and not along suture—terminating on suture in many, but not all, basal Neoisoptera; reversed notably in Termitidae); Sc short, R1 simple, Rs running parallel to costal margin, Rs without apical parallel posterior inferiors (apical parallel posterior inferiors present in Hodotermitidae), radial field narrow, M running about halfway between Rs and CuA and sclerotized like CuA (rather than like Rs). Hind wing without anal lobe (present in Mastotermitidae). Cerci dimerous (observable only in Tanytermitalis, unknown for Tanytermes), as in Kalotermitidae.

Cerci and forewing venation somewhat similar to some Kalotermitidae, likely a reflection of the position of Tanytermitidae as closer to Icoisoptera than to more basal grade termites (Engel et al., 2009, 2016), but differing in the shorter CuA (subapical or apical termination in most Icoisoptera, terminating at apical third in Tanytermitidae). In addition, ocelli are present in imagoes of Icoisoptera, while lacking in the present family.