Clupeidae Cuvier 1816, gen. nov.

† Paleopiquitinga , gen. nov.

Type-species. † Knightia brasiliensis Woodward, 1939.

Etymology. The generic epithet is derived from the Greek word, palaios, ancient; plus piquitinga, a Tupi- Guarani name for a living herring [Lile piquitinga (Schreiner & Ribeiro, 1903)] originally described in Pies & Marcgraf (1648); gender female.

Diagnosis. Slender and small-sized (rarely exceeding 80 mm TL) clupeoid fish recognized by the following combination of features: head length contained 3 ½ in SL and equals to maximum body depth; anterior and posterior fontanels absent in the midline of cranial roof; longitudinal ridges on frontals; preepioccipital and large temporal fossae present; supratemporal commissure piercing parietal and supraoccipital bones; pterotic contributes to the temporal fossa; quadrate-mandible joint placed below the anterior half of orbit; jaws toothless; short lower jaw with deep coronoid process; two supramaxillae; seven branchiostegal rays; third postcleithrum rod-shaped; eight slender supraneural bones; 38 vertebrae, 15 caudal; large notochordal canal; short-based dorsal and anal fins; dorsal fin originating at the middle point of the body, anterior to pelvic fin; seven-rayed pelvic fin originating slightly behind vertical line anterior to the origin of dorsal fin; intermuscular epineural and epipleural bones extending over caudal region; predorsal scutes absent; at least 11 prepelvic abdominal scutes; eight postpelvic scutes; triangular pelvic scute; anteriormost preural vertebrae bearing long and thin neural spines; elongate leaf-like process of neural arch of first preural centrum; one epural; parhypurapophysis present; neural arch of the first preural centrum long and leaf-like; first ural centrum fused to first ural centrum; six hypurals; three uroneurals, with the first forming a strong pleurostyle; mid-sized cycloid scales with vertically arranged circuli; perforated scales of lateral line absent.

Remarks. † Knightia eoceana from the Lower Eocene of Wyoming was described by Jordan (1907) as the type-species of † Knightia. Grande (1982) furnished a revised diagnosis for † Knightia based on a combination of the following features: i) one supramaxillary, ii) complete series of 12–14 dorsal scutes (each one with unsculptured wings and median keel), and (iii), relatively few vertebrae (36 to 40) and pleural ribs (20-22 pairs). He listed seven valid species: † Knightia eoceana, † Knightia alta, † Knightia “ copei ”, † Knightia vetusta, † Knightia n.sp (Tertiary of eastern China), † Knightia ? yuyanga, and †“ Knightia ” brasiliensis. Afterwards, Grande (1985), concerning † “ Knightia ” brasiliensis, pointed out that “for reasons discussed above, this species must be removed from † Knightia (no new genus is proposed here without further study)”. † Paleopiquitinga brasiliensis possesses two supramaxillaries and lacks dorsal scutes. Only the lesser number of vertebrae and pleural ribs are shared by † Paleopiquitinga and † Knightia; which are also shared by † Gosiutichthys parvus (see Grande, 1982; 1985).