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ONTOGENY AND SYSTEM ATICS OF FISHES- AHLSTROM SYMPOSIUM 



harengus larvae were shown to be affected by temperature and 

 salinity (Hempel and Blaxter, 1961); morphometric characters 

 in Gikhristella aestuarius adults were found to differ between 

 estuaries with different types of prey items (Blaber et al., 1981). 



There are several characters which may be useful in system- 

 atics when they are described for more clupeiform species. The 

 melanophores on the caudal fin dorsal and/or ventral to the 

 notochord tip in small larvae have been described for a few 

 species. Harengida jaguana has dorsal melanophores only at 

 first, then both dorsal and ventral (Houde et al., 1974). Opis- 

 thonema oglinum has ventral ones (Richards et al., 1974). Sar- 

 dinella brasiliensis. S. maderensis and S. zunasi have just ven- 

 tral melanophores but Sardine/la rouxi has both. Slight 

 differences in pigmentation over the brain and on the mid-dorsal 

 and mid-ventral postanal body midline have been used to iden- 

 tify scombrid larvae. Small scombrid larvae are otherwise very 

 similar to each other as are clupeoid larvae. The development 

 of free neuromasts and the lateral line has been described for a 

 few species (Blaxter et al., 1983). Development of the swim- 

 bladder and its unique connection with the inner ear should be 

 useful (Hoss and Blaxter, 1982). Ephemeral basihyal teeth were 

 observed on Opisthonema oglinum and Harengula jaguana lar- 

 vae (Richards et al., 1974; Houde et al., 1974). Two patterns 

 of nasal epithelium cells have been observed with scanning elec- 

 tron microscopy (Yamamoto and Ueda, 1 978). Harengula, Sar- 

 dinops and Konosirus had one pattern while Etrumeus (a clu- 

 peid) had the same pattern as Engraulis, an engraulid. 



Although the eggs and yolk-sac larvae of clupeiforms have 

 many characters of potential systematic importance, the taxo- 

 nomic characters of the older larvae (meristics, fin position, and 

 pigmentation) will tend to be redundant with the same adult 

 characters. However, clupeoids are easily reared in the labo- 

 ratory so direct experimental evaluation of the polarity of adult 

 character states by comparative developmental studies is pos- 

 sible. 



Relationships 



The clupeiform fishes are considered a well-defined mono- 

 phyletic group based on their unique otophysic connection, the 

 caudal skeleton, and other characters (Greenwood et al., 1966). 

 The distribution of species within genera, genera within subfam- 

 ilies, and number and taxonomic rank of categories within the 

 group are not agreed upon (Gosline, 1971, 1980; Miller, 1969; 

 Nelson, 1967, 1970, 1973; Whitehead, 1972, 1973). J. S. Nelson 

 (1976) lists the families Chirocentridae, Denticipitidae, Clu- 

 peidae, and Engraulidae. He gives seven subfamilies of herrings 

 (Dussumieriinae, Clupeinae, Pellonulinae, Alosinae, Doroso- 

 matinae, Pristigasterinae, and Congothrissinae) and two 

 subfamilies of anchovies (Engraulinae and Coilinae). Spralel- 

 loides is separated from the Dussumieriinae and given subfamily 

 rank by Whitehead (1972. 1973). Jenkinsia is the western At- 

 lantic spratelloidin. 



Based on the gill arches Nelson (1967) concluded that the 

 Dussumieriinae (including Spratelloides and Jenkinsia) were the 

 most primitive clupeid family; the Pristigasterinae were also 

 primitive but with distinctive specializations; the Clupeinae were 

 more advanced, but linked to the Dussumieriinae by Clupea 

 and Sprattus; the Alosinae and Dorosomatinae were closely 

 related and perhaps both derived from the Clupeinae; and the 

 Pellonulinae, lacking the specializations of the Alosinae and 

 Dorosomatinae, most resembled the Clupeinae. Expanding his 



study of gill arches in the Clupeidae to the hyobranchial ap- 

 paratus in the Clupeiformes, Nelson (1970) divided the order 

 into the superfamilies Chirocentroidae, Engrauloidae. Pristi- 

 gasteroidae, and Clupeoidae. The Clupeoidae were suggested to 

 consist of two families: the Clupeidae composed of the Dus- 

 sumieriinae, Pellonulinae, and Alosinae in part; and the Do- 

 rosomatinae composed of the Dorosomatinae plus Hilsa from 

 the Alosinae and Harengida and Sardinella from the Clupeinae. 

 Sardina and Alosa were aligned with Clupea, Polamalosa, and 

 Etrumeus in his tree depicting relationships of representative 

 genera (Nelson, 1970: Fig. 1 1). 



Whitehead (1972, 1973) acknowledged that radical changes 

 in clupeid classification could be expected but retained the 

 subfamilies Dussumieriinae, Spratelloidinae, Clupeinae, Pel- 

 lonulinae, Alosinae, Dorosomatinae, and Pristigasterinae in his 

 works which were chiefly concerned with the identification of 

 genera and species. 



The most recent comprehensive work is that of Wongratana 

 (1980) on the Clupeidae and Engraulidae of the Indo-Pacific. 

 He examined over 14,000 specimens and considered many me- 

 ristic and morphological characters including gill rakers, epi- 

 branchial organs, predorsal bones, caudal osteology, circumor- 

 bital bones, gut form, the gas bladder, scale striae, and the patterns 

 of scale distribution on the body. No numerical, cladistic, or 

 phenetic analyses were done. Taxonomic characters were dis- 

 cussed with respect to apparent evolutionary trends and relative 

 importance. Wongratana retained the subfamilies of Whitehead 

 (1972). The Spratelloidinae were diagnosed by a bony process 

 on the 6th and 1 2th principal caudal rays. Spratelloides is also 

 unique among Indo-Pacific clupeids in having a single epural. 

 Jenkinsia, the spratelloidin in the Western Atlantic, also has a 

 single epural (Hollister, 1936). The Alosinae and Dorosomatin- 

 ae were kept separate and the Pristigasterinae were accorded 

 subfamily status although considered quite distinct from the 

 other clupeids. The Dussumieriinae and Pellonulinae were con- 

 sidered the most primitive groups, the Alosinae and Doroso- 

 matinae the most advanced, and the Spratelloidinae and Clu- 

 peinae were considered intermediate. Within the anchovies, the 

 Coiliinae have one epural while the Engraulinae have two {En- 

 graulis) or three (Papuengraulis). The Coiliinae were considered 

 primitive relative to the Engraulinae although specialized in 

 many respects. 



Wongratana ( 1 980) found that the number of predorsal bones 

 varies from one to thirty in the clupeids and engraulids (Chi- 

 rocenlrus has none). Some engraulids and pellonulins have a 

 gap between the posterior predorsal bone and the first dorsal 

 pterygiophore which he interpreted as evidence that the dorsal 

 fin has migrated posteriad during evolution. It would be inter- 

 esting to compare the patterns of dorsal bones and the anteriad 

 migration of the dorsal fin during larval metamorphosis. The 

 "dorsal scutes" of Clupanodon ihrlssa were found to be the 

 exposed tips of predorsal bones (Wongratana, 1980). The only 

 double-armored herrings known now are Polamalosa and Hy- 

 perlophus in the Pellonulinae, and Elhmidium in the Alosinae. 

 Dorsal scutes are interesting because they occurred in herring- 

 like fossils (Diplomystus, Knightia, and Gasteroclupea) which 

 resemble pristigasterins (Nelson 1970). 



Because he examined so many species from such a wide area 

 Wongratana (1980) was able to clear up many nomenclatural 

 questions and to correct previous misidentifications which had 

 been based on limited material. He also described 24 new species 



