SUBFAMILY SCALPELLINAE PILSBRY, 1907 MOLECULAR GROUP A OF LIN ET AL. (2015: FIG. 3)

Amended diagnosis

Scalpellids in which the rostrolatus is broad, low, straplike, and gently incurved. The rostrum is broader than high, rectangular, trapezoidal or triangular, and large triangular lateral surfaces contact the interior of the rostrolatus. The articulation surface between the rostrum and rostrolatus extends over the entire height of both plates.

Included genera

Arcoscalpellum Hoek, 1907, Arcuatoscalpellum gen. nov., Diotascalpellum gen. nov., Graviscalpellum Foster, 1980, Regioscalpellum gen. nov., and Scalpellum Leach, 1817 .

Remarks

This definition of Scalpellinae differs in major respects from that of Zevina (1978a), for whom the family was characterized by the subapical carinal umbo, the inflexed carina, and the subapical umbones of the upper and inframedian latus; however, the group as thus defined is polyphyletic (see above), and these features evolved independently a number of times within the Scalpellidae . The subfamily is therefore rediagnosed to include the basal group of scalpellids shown in Figure 14, which are technically paraphyletic, but can be readily identified.