530 



ONTOGENY AND SYSTEMATICS OF nSHES-AHLSTROM SYMPOSIUM 



taxa are plesiomorphic character states, the one notable excep- 

 tion being caudal-peduncle grooves. 



In addition to possessing different character states 3-8 and 

 14 as listed above, Freihofer (1963) observed that the Caran- 

 gidae and Nematistiidae differ in the course of the nerves of the 

 ramus lateralis accessorius (RLA) complex; the former having 

 pattern 9 and the latter pattern 10 (reduced). Nematistius also 

 differs in having two foramina in the scapula; a typically large 

 one and a smaller more posteriorly positioned foramen (absent 

 in carangids) that also occurs in the Rachycentridae. Like the 

 two RLA nerve patterns, the derived character state for the two 

 scapular foramina conditions has not been determined. Never- 

 theless, the inclusion of Nematistius in the Carangidae would 

 make the family paraphyletic (unless the three echeneoid fam- 

 ilies are also included) and impossible to define based on shared 

 derived characters. 



Familial position of Parastromateus 



Several recent authors have followed Apsangikar (1953) or 

 Suzuki ( 1 962) in recognizing Parastromateus either as a subfam- 

 ily of the Carangidae or as the sole representative of the mono- 

 typic Formionidae (=Apolectidae or Parastromatidae). All the 



characters used to justify the latter classification, with one ex- 

 ception discussed below, have been autapomorphic characters 

 which can provide no information about relationships. That the 

 genus should be assigned to the Carangidae is clearly indicated 

 by the possession of derived character states 3-5 and 14-16 

 discussed previously. 



Haedrich (1971) noted that Parastromateus (=Apolectus) is 

 the only fish with a pattem-9 ramus lateralis accessorius nerve 

 system that has a "pons moultoni." In an addendum to his 

 paper it was suggested that retention of the pons is a primitive 

 character state. It should be emphasized that very few carangoids 

 have been examined for the presence of this easily overlooked 

 structure. Until the distribution of this character has been de- 

 termined for the major lineages of carangoids, its phylogenetic 

 significance can not be evaluated. Similarly, no data have been 

 presented to substantiate assigning Parastromateus to its own 

 subfamily within the Carangidae. 



Department of Ichthyology, The Academy of Natural Sci- 

 ences, 19th and The Parkway, Logan Circle, Phila- 

 delphia, Pennsylvania 19103. 



Mugiloidei: Development and Relationships 

 D. P. DE Sylva 



MUGILOIDEI is one of three closely related suborders, to- 

 gether with Sphyraenoidei and Polynemoidei, in the Per- 

 ciformes. The suborder is represented by a single family, the 

 Mugilidae. Until recently, the Atherinidae had been considered 

 close relatives of the Mugiloidei. Within the family Mugilidae, 

 classical morphological taxonomic analyses have been applied 

 to regional groupings rather than to the family as a whole (Weber 

 and de Beaufort, 1922;Roxas, 1934; Smith, 1935, 1947;Schultz, 

 1946; Ishiyama, 1951; Thomson, 1954; Ebeling, 1957, 1961; 

 Lindberg and Legeza, 1969; Ben-Tuvia, 1975). Hence, the sys- 

 tematics of the family are poorly understood. 



Mullets are characterized by thick, streamlined bodies, deeply 

 forked caudal fin. large cycloid or weakly ctenoid scales, and 

 the lack of a lateral line. The mouth is small, the jaws have 

 small teeth or none, and the gill rakers are long and slender, the 

 latter assisting the pharyngeal jaw apparatus to form a filtering 

 apparatus (Lauder and Liem, 1983). They share, with the thread- 

 fins and barracudas, the characteristic of having two widely 

 separated dorsal fins. Two subfamilies of mullets are recognized, 

 the Mugilinae and the Agonostominae (Jordan and Evermann, 

 1896-1900). The latter have sessile teeth which attach directly 

 to the jaws, a flat preorbital, and only 2 anal spines in the adult. 

 The Mugilinae have flat labial teeth, if any, connected to the 

 jaws by elongated fibers, a ridged and grooved preorbital, and 

 3 anal spines in the adult. 



The Mugilinae occur worldwide except in polar regions, while 

 the Agonostominae are confined to Central America, the west- 



em Indian Ocean, the tropical west Pacific, and the Australian 

 coastline. Mullets occur in oceans, bays, estuaries, and fresh 

 water. They are uniformly important as food for humans and 

 an important prey in the food web. They seldom exceed 1 meter. 



Development 



Many studies exist on the eggs, larvae, and post-larval stages 

 of mullets in comparison to other families, but only a few are 

 comprehensive, and most deal with a single species (e.g., An- 

 derson, 1957;Dekhnik, 1973; Farrugio, 1977; Kuo et al.. 1973; 

 Lai. 1979; Martm and Drewry, 1978; Sanzo, 1936; Tung, 1973; 

 Vialli, 1937; Yang and Kim, 1962; Yashouv and Bemer-Sam- 

 sonov, 1970). However, a general overview of each stage can 

 be summarized. 



Eggs are pelagic, spherical, and transparent, with the surface 

 of the egg being smooth and usually without sculpture (Fig. 280). 

 The yolk is unsegmented. the perivitelline space is narrow, and 

 there is one or more oil globules. During development, several 

 oil globules merge with each other, becoming situated on the 

 yolk sac upon hatching. Egg sizes for various species of European 

 and African mugilids range from 0.6 to 1 .3 mm and vary greatly 

 in diameter from one geographic area to another. Although most 

 eggs have similar pigmentation, different species have similar, 

 though sometimes overlapping spawning seasons, which may 

 offer a clue in the analysis of phyletic relationships and mugilid 

 evolution. 



Larval pigmentation ranges from relatively light to heavy (Fig. 



