Labroidei: Development and Relationships 

 W. J. Richards and J. M. Leis 



THE most recent concept of this group concludes that the 

 Pomacentridae, Cichhdae, Embiotocidae, and Labridae 

 comprise a monophyletic assemblage (Kaufman and Liem. 1982). 

 Kaufman and Liem (1982) include the Odacidae and Scaridae 

 in the expanded family Labridae. For present purposes, we em- 

 ploy the traditional view of three separate families. Pomacen- 

 tridae is a large primarily marine family of about 23 genera and 

 230 species found in the tropics and warm temperate waters of 

 the world's oceans (Allen, 1 975a). Cichhdae is a fresh and brack- 

 ish water family found in the Americas, Africa including Mad- 

 agascar, coastal western Mediterranean, and the coastal areas 

 of India. It is a large family comprised of about 85 genera and 

 perhaps 700 species making it the second largest perciform fam- 

 ily (Stiassny, 1981). Embiotocidae is found only in the North 

 Pacific with 2 species around Japan and Korea. 18 off the west 

 coast of the LI.S., and 1 confined to freshwater of California 

 (Tarp, 1 952). Labridae is a tropical and warm temperate marine 

 family of about 58 genera and about 400 species (Russell, 1 980). 

 Odacidae is a temperate marine group of 4 genera and 1 2 species 

 confined to New Zealand and southern Australia (M. F. Gomon 

 and J. R. Paxton, pers. comm.). Scaridae is a tropical marine 

 family of about 12 genera and 70 species (Schultz, 1958). Table 

 1 30 summarizes meristic characters of labroid fishes. 



Development 



The family Embiotocidae is a small family of viviparous species 

 that has several unusual morphological specializations during 

 development as reviewed by Wourms (1981). During gestation, 

 the vertical fins hypertrophy and develop spatulate extensions, 

 and the alimentary canal hypertrophies, especially the hind gut. 

 All these specializations appear due to viviparity and are not 

 treated further here. 



Cichhdae, so far as known, all undertake elaborate parental 

 care (Breder and Rosen, 1966). The eggs are slightly elliptical 

 or irregularly shaped. The eggs are also adhesive except for those 

 which are orally incubated. There is a vast literature on repro- 

 ductive behavior most of which describes spawning behavior 

 and parental care, but there is little descriptive information on 

 larvae since many species transform directly from yolk sac to 

 juvenile (Balon, 1981b; Noakes and Balon, 1982). Balon (1959) 

 described the young of Cichlasoma cyanoguttalum. The larvae 



of laboratory reared Cichlasoma octofascialum are depicted in 

 Fig. 292. The larvae of Pterophy/him have an adhesive disk on 

 the head for attachment to substrate and several stages are de- 

 picted in photographs in Innes (1956). The Cichlasoma larvae 

 (Fig. 292) have unusual structures on the head though they were 

 not observed to be used as holdfast organs (A. W. Kendall, 

 pers. comm.). Larvae of Symphysodon cling to the mucus of the 

 parent and actually derive nourishment from it (Breder and 

 Rosen, 1966). Balon (1977) thoroughly describes the develop- 

 ment of Labeotropheus, a mouth brooder which has direct de- 

 velopment. 



Pomacentridae have demersal eggs with an adhesive pedestal; 

 the male guards and incubates them. Few species have been 

 studied from an early life history perspective (Table 131). Most 

 have pelagic larvae, but at least one species (Acanthochromis 

 polyacantha) broods and protects the young in a manner similar 

 to cichlids (Robertson, 1973). Larval development is direct with 

 few larval specializations and no specialized stages between lar- 

 vae and juveniles. The sequence of fin formation is variable. 

 All fins may be formed as early as 3 mm, but depending on 

 species, settlement may not occur until 1 8 mm. The gut is coiled 

 at hatching. The larvae arc very similar to percoids and may 

 be easily confused with numerous families (Leis and Rennis, 

 1983). In general they have a short, coiled, triangular gut, an 

 inconspicuous gas bladder which is covered by melanophores, 

 and weak preopercular spination (Fig. 293). 



Some early life history information is available on about one- 

 half of the labrid genera (Table 1 30). The vast majority of labrids 

 spawn small (0.5-1.1 mm) pelagic eggs, but three northeast 

 Atlantic genera have adhesive, demersal eggs with parental care 

 (Table 131). Demersal labrid eggs are small (< 1 mm) and ad- 

 hesive, but do not have an adhesive pedestal. Labrid eggs usually 

 have a smooth chorion and a single oil globule. Newly hatched 

 larvae have the yolk sac protruding anteriorly in front of the 

 head with the oil globule (if present) at the anteriormost postion. 

 The larvae are generally elongate and laterally compressed with 

 a deep caudal peduncle, but some species are deep-bodied (Fig. 

 294). The gut is rugose and is initially straight; coiling may be 

 delayed until after flexion in some species. The head is com- 

 pressed and almost always lacks spines. Scales do not form prior 

 to settlement. In tropical forms the eye may be round, ovoid. 



Table 130. Some Meristic CHAEtACTERS of Labroid Fishes. N is the approximate number of recent species largely after Nelson (1976). Other 

 data from Gunther, 1862; Boulenger, 1915; Tarp. 1952; Miller and Jorgensen, 1973; Russell, 1980; Leis and Rennis, 1983; Sanchez, 1981; and 



J. R. Paxton, pers. comm. 



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