JOHNSON: EVERMANNELLIDAE 



253 



sheets over the dorsal and dorsolateral margins of the gut and 

 these sections expand ventrad as well as longitudinally with 

 growth. In specimens larger than 35 to 45 mm SL the peritoneal 

 pigment sections coalesce to form the complete gut-enclosing 

 pigment tube characteristic of adults. 



Other pigmentation (Fig. 129).— The major pattern of body pig- 

 mentation in evermannellid larvae occurs in two phases, a larval 

 phase and a juvenile phase, with a gradual transition between 

 the phases. In smaller larvae (less than 12-15 mm SL) the most 

 prominent body pigmentation consists of a pattern of pigment 

 bands arranged along the myosepta. Typically these bands are 

 arranged in groups (symmetrically distributed in epaxial and 

 hypaxial myotomal bands in the tail region, nonsymmetrical 

 and predominantly epaxial in the trunk region), resulting in a 

 characteristic barred appearance. In larvae larger than 1 2 to 15 

 mm SL the body pigmentation characteristic of adults begins 

 to appear. In Odontostomops juvenile phase pigmentation is 

 characterized by the development of numerous highly punctate 

 melanophores generally distributed over the head and body. In 

 Evermannella the juvenile phase is typically characterized by 

 the development of three rows of very large melanophores, each 

 row associated with one of the 3 main divisions of the trunk/ 

 tail musculature. The median row, that associated with the lat- 

 eralis superficialis, is limited to the tail. Both of the other rows, 

 epaxial and hypaxial, extend the length of the body, from the 

 posterior border of the head (or nearly so) to the caudal peduncle. 

 In Coccorella the juvenile phase pigmentation tends to be in- 

 termediate in state between that of Odontostomops and Ever- 

 mannella. the developing melanophores tend to be larger and 

 more prominent than in Odontostomops. but much more nu- 

 merous and not arranged in rows as in Evermannella. Body 

 pigmentation in juveniles larger than 25 to 30 mm SL is similar 

 to that in adults. Development of adult pigmentation in ever- 

 mannclid larvae is associated with gradual (all statements im- 

 plying time course are based solely on size increments) disap- 

 pearance of the larval myoseptal pigment bands. Four of the 

 seven evermannellid species (Coccorella atlantica. C. atrata. 

 Evermannella megalops. Odontostomops normalops) are highly 

 melanistic as adults. In Evermannella balho. E. indica. and es- 

 pecially E. ahlstromi the pigmentation in adults tends to be 

 much more mottled, with numerous, variably-sized melano- 

 phores (some very large) on a light brown (in alcohol) ground 

 color. Obscured in adults is the longitudinal tnlateral melano- 

 phore pattern characteristic of juveniles. 



Gut morphology (Fig. 129). — \n all evermannellids the stomach 

 is a heavily muscularized blind sac. The stomach expands pos- 

 teriad with larval growth reaching its full extension (to a vertical 

 just behind the pelvic fin base) in specimens exceeding 20-25 

 mm SL. Larvae of Coccorella are distinguished by the unique 

 possession of a pyloric caecum that expands anteriad with growth 

 and enters the head in larger larvae, juveniles and adults (Fig. 

 129E). The caecum is visible as a short, blind, bud-like sac on 

 the ventro-anterior margin of the intestine in the smallest known 

 larvae of Coccorella. Wassersug and Johnson (1976) describe 

 in detail the structure and development of this remarkable or- 

 gan. Neither Evermannella nor Odontostomops nor (as far as is 

 known) any other alepisauroid possess a pyloric caecum. 



rra«s/orwa?/o/i. — Development of juvenile phase pigmentation 

 signals the onset of transformation in all evermannellid larvae. 



2,8,12,19 



Fig. 1 30. Proposed relationships among evermannellid species based 

 on adult and larval characters. Integers indicate derived character states, 

 listed in Table 67, possessed by taxa above indicated point in dendro- 

 gram. 



Transformation in Evermannellidae is gradual, adult characters 

 are essentially acquired one by one, and there are no abrupt and 

 radical changes in morphology. In all evermannellid species, 

 individuals larger than 25 to 30 mm SL are (except for final 

 fusion of pentoneal pigment) essentially miniature adults and 

 can be distinguished readily on the basis of adult characters 

 (e.g., eye morphology, presence or absence of dentary fossa, 

 posterior extent of lateral line, arrangement of cephalic latero- 

 sensory pores, dentition, pigmentation, meristic and morpho- 

 metric characters). Final fusion of the peritoneal pigment sec- 

 tions occurs by about 35 mm SL (Coccorella. Evermannella) or 

 by about 45 mm SL (Odontostomops). 



Relationships 



The evermannellids were poorly known until the completion 

 of Johnson's (1982) revision. Currently recognized are 7 species 

 in 3 genera (Fig. 130). Phylogenetic analysis involving presum- 

 ably derived states of 1 6 characters or character complexes sup- 

 ported previous allocation of species among the 3 genera. In the 

 listing that follows characters are given as character number 

 (derived state number). Of the 1 6 characters, 2 involved larval 

 features (Table 67: 15, 16). Of the 14 adult characters, 5 rep- 

 resented novel autapomorphies (Table 67: 2. 3, 8, 10, II), 3 

 exhibited a sequence of 3 steps (Table 67: 1,6, 12) and 6 rep- 

 resent reductive characters (Table 67: 4, 5, 7, 9, 13, 14). Odon- 

 tostomops is specialized in having 12 or more serially arranged 

 pentoneal pigment sections 15 (18) and in two reductive char- 

 acters 7 (9) and 9 (11). Coccorella exhibits autapomorphies in 

 four characters: cephalic extension of pyloric caecum 2(3), pres- 

 ence of luminous tissue 3 (4), posterior expansion of ethmoid 

 cartilage 8 (10), arrangement and morphology of dentary and 

 palatine teeth II (13) and is apomorphous in two additional 

 reductive characters 12 (14) and 14 (17). Coccorella atrata is 

 apomorphous in two reductive characters, 12(15) and 13 (16). 

 Linking Coccorella and Evermannella are intermediate states 

 in the two 3-step characters 1(1) and 6 (7). Evermannella shows 



