Superorder Clupeomorpha

Otophysic (ear-swim bladder) connection comprising a pair of anterior extensions of the swim bladder that enter the skull through the exoccipital and extend into the prootic and often into the pterotics within the lateral wall of the braincase to connect with the utriculus of the inner ear (unlike that occurring in any other group); second hypural fused at base to first ural centrum in all stages of development, but the first hypural free at its base from first ural centrum (autogenous); single pelvic scute present at insertion of the pelvic fin (inconspicuous in adult Chirocentrus) and most species with series of median scutes along abdomen before and behind pelvic fin; branchiostegal rays usually fewer than 7, rarely up to 20; body compressed in most; pneumatic duct extending from swim bladder to gut at or near stomach (opening into the dorsal wall of the stomach, relatively anteriorly, in most Engraulidae, Pristigasteridae, and in Dussumieria, and in some the duct extends from the swim bladder to the anus); jaws not protrusible; usually two supramaxillae. The first two diagnostic characters are described in Patterson and Rosen (1977).

Several lines of clupeomorphs, both fossil and extant, have members that are double-armored; that is, they have predorsal as well as ventral scutes. In some of these there are only one or two predorsal scutes (double-armored engraulids of the Indo-Pacific), while in others there is a series (Paraclupea, Diplomystus, Ellimmichthys, Knightia, Hyperlophus, Potamalosa, Ethmidium, Gosiutichthys, and Clupanodon). The double-armored feature has evolved (or possibly been lost) independently several times.

The Lower Cretaceous Erichalcis is a clupeomorph of uncertain position. The Upper Cretaceous Ornategulum is probably a preclupeomorph. Forey (2004) considered the Lower Cretaceous Spratticeps as sister to the extant Clupeiformes plus fossils such as Santanaclupea. The higher classification of this taxon has not changed much from that presented by Grande (1985).

Five families, 84 genera, and about 364 species. About half the species are Indo-West Pacific, and almost one-quarter are in the western Atlantic. About 79 species occur primarily in freshwater.

fOrder ELLIMMICHTHYIFORMES. No recessus lateralis (infraorbital canal not merging with preopercular canal but extending through dermo-sphenotic); lateral line complete; patch of teeth on the parasphenoid similar to that in Osteoglossum; large foramen in the anterior ceratohyal; parietals meeting at the midline between the supraoccipital and the frontals.

The recognition of this order and its one family follows Grande (1985).

+Family PARACLUPEIDAE (= Ellimmichthyidae). Lower Cretaceous to Middle Eocene; freshwater and marine.

Subrectangular dorsal scutes; ventral scutes extending from isthmus to anus; pelvic fin, as far as known, in advance of dorsal fin; two supramaxillary bones; parhypural fused to first preural centrum; lateral line complete. Some species had a very deep body.

The classification follows Forey (2004); Zaragueta Bagils (2004) noted some biogeographical questions and gave stratigraphic and geographic occurrence for the genera and species.

Seven fossil genera, recognized in two lineages (Chang and Grande, 1997; Chang and Maisey, 2003; Forey, 2004): i) Armigatus, Diplomystus, Sorbinichthys, and Triplomystus, and ii) Paraclupea, Ellimma, and Ellimmichthys.

Order CLUPEIFORMES (27)—herrings. Recessus lateralis present (part of the otophysic connection in which various sensory canals merge within a chamber in the otic region of the neurocranium, not known in any other group); parasphenoid teeth absent; no large foramen on the anterior cerato-hyal; parietals separated by the supraoccipital; no leptocephalus larvae. Most are plankton feeders, with long and sometimes very numerous gill rakers that serve as straining devices. This group is very important in the world's commercial fisheries.

Five families, 84 genera, and about 364 species.

Suborder Denticipitoidei

Family DENTICIPITIDAE (93)—denticle herrings. Freshwater; coastal rivers of Nigeria and Cameroon, Africa.

Denticles (odontodes) on all roofing bones of skull; no supramaxillae; four or five branchiostegal rays, first (median) pair with denticles on anterior edge; ventral half of head with "furred" appearance from small denticles; lateral line complete; ventral scutes present; 16 principal caudal fin rays; caudal skeleton with one uroneural (other clupeomorphs have three) and parhypural fused to first preural centrum; recessus lateralis relatively primitive, incomplete in not having a separate opening for the supraorbital laterosensory canal. Scales in lateral line 37-40 and vertebrae 40-41 in the living species. Maximum length 6 cm.

The one fossil species, Palaeodenticeps tanganikae, probably of Miocene Age, is known from Tanzania, Africa.

One species, Denticeps clupeoides (note that the family name is not spelled Denticepitidae).

Suborder Clupeoidei. Lateral line not extending onto body (a canal does extend beyond the gill cover and branches over one or two scales, but there are no pored lateral-line scales); 19 principal caudal fin rays; first uroneural fused to first preural centrum (located in front of the reduced first ural centrum, which is fused to the second hypural in all clupeomorphs); parhypural usually separate from the first preural centrum. Yolk segmented (also in Bothidae). There is much diversity in the swim bladder of clupeoids, with the extreme specializations found in the pristigasterids.

The classification of this suborder is based primarily on Grande (1985), Whitehead (1985), and Whitehead et al. (1988). Grande (1985) and Grande and Nelson (1985) gave an elevated rank to many of the groups. They recognized three superfamilies in this suborder: Engrauloidea with two families (vs. one family and two subfamilies), Pristigasteroidea with two families (vs. one family and two subfamilies), and Clupeoidea (with the sister families Chirocentidae and Clupeidae as given here). Thus, the same phylogenetic arrangement is adopted here while maintaining the family names as generally recognized. Di Dario (2002) presented evidence from new characters that Pristigasteridae may be the basal group of Clupeoidei and sister to a clade comprising Clupeidae + Engraulidae; the implications of this possible phy-logeny in finding new characters to test the possible sister-group relationship between Clupeomorpha and Ostariophysi were given.

Family PRISTIGASTERIDAE (94)—longfin herrings. Primarily marine, some freshwater in South America and southeast Asia; Atlantic, Indian, and Pacific in tropical and some subtropical seas.

Mouth usually superior, otherwise terminal; jaw teeth small, canines only in Chirocentrodon; abdominal scutes present; anal fin long, 30-92 rays; six bran-chiostegal rays; scales in lateral series about 35-55; vertebrae usually 40-55, up to 62 in Raconda. Pelvic fins are absent in several species as noted below. Grande (1985) recognized this taxon on the basis of having the predorsal bones orientated either vertically or inclined anterodorsally (vs. being inclined posterodorsally as in nearly all other teleosts) and no notch in third hypural of the caudal skeleton (vs. having a distinct notch that creates a gap with the second hypural as in most clupeomorphs). He recognized this group as a superfamily, giving family status to the following subfamilies and noted that Ilisha, as recognized here, is not monophyletic. Maximum length about 55 cm SL, attained in Pellona flavipinnis of South America; most under 25 cm.

Nine genera with 34 species (e.g., Whitehead, 1985; Randall, 1994; Munroe, 1999, 2003a; de Pinna and Di Dario, 2003). Four species are freshwater; the rest are marine, occasionally entering brackish water.

Subfamily Pelloninae. Grande (1985) recognized this group on the basis of having the maxillary-premaxillary gap covered by bone, either a toothed hypomaxilla bone or an extension of the maxilla (vs. having a gap as in other clupeomorphs; the hypomaxilla is a bone that is part of the gape of the upper jaw and situated behind the premaxilla, it is also found in Harengula). The pelvic fin is absent in the two small species of Neoopisthopterus and in the single species of Pliosteostoma. The one small species of Chirocentrodon has strong conical teeth and caninelike teeth in front (there are also teeth in the gap separating the premaxillae).

Five genera, Chirocentrodon, Ilisha, Neoopisthopterus, Pellona, and Pliosteostoma, with 23 species.

Subfamily Pristigasterinae. Grande (1985) recognized this group on the basis of having a bony process on the first pleural rib that articulates with the shoulder girdle (not known from any other teleost except Ilisha africana, which Grande would place in this taxon). The pelvic fin is absent in the six species of Opisthopterus, the three of Odontognathus, the single species of Raconda (which also lacks the dorsal fin), and usually in the single species of the exceptionally deep-bodied Amazonian Pristigaster.

Four genera, Odontognathus, Opisthopterus, Pristigaster, and Raconda, with 11 species.

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