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Fishery Bulletin 89(2). 1991 



contrast, in the central and western Gulf of Mexico 

 from the Mississippi Delta to Cabo Rojo, Veracruz, 

 where S. civitatium is very abundant, substrates on 

 the inner shelf consist largely of terrigenous quartzite 

 sands, silts, and clays delivered primarily by Mississippi 

 and Rio Grande rivers (van Andel 1960). 



Substrate preference may also affect the distribution 

 of S. civitatium in coastal seas off the southeastern 

 United States. The depth of occurrence (ll-40m, see 

 below) for S. civitatium apparently coincides with sand- 

 silt substrates on the inner portions of the shelf, and 

 this species is absent from live-bottom habitats occur- 

 ring at similar depths (Struhsaker 1969). 



The specimen of S. civitatum reported by Lazzaro 

 (1977:69) from the continental shelf off Uruguay is 

 neither this species nor any other of the Symphurus 

 plagusia complex (those possessing 12 caudal fin rays, 

 a 1-4-3 ID pattern, and an unpigmented peritoneum). 

 The body shape evident in the photograph, meristic 

 features, and great depth of occurrence (183 m) indicate 

 the specimen is probably S. ginsburgi Menezes and 

 Benvegnu. 



Bathymetric distribution Although S. civitatium has 

 been collected over a wide depth range of 1-73 m (Table 

 11), its center of abundance, based on overall frequen- 

 cy of capture and general abundance, occurs between 

 11 and 45m. Approximately 91% (199/216) of the 

 specimens examined in the present study were cap- 

 tured at these depths. The deepest captures were at 

 73 and 62 m, where a single fish was taken each time. 

 It is unusual for adult S. civitatium to occur in shallow, 

 inshore regions. Of four fish collected shallower than 

 10 m, three were small juveniles (< 35 mm SL). Recent- 

 ly, several small juveniles (22-24 mm SL) have been col- 

 lected in the Cape Fear River estuary, North Carolina 

 (S.W. Ross, Dep. Nat. Resour., Morehead City, NC, 

 pers. commun. 24 July 1985). It is not known how 

 regularly this species occurs in these inshore areas or 

 whether the recent captures represent isolated occur- 

 rences; however, Schwartz et al. (1981) listed this 

 species as rare in the Cape Fear River estuary. Sea- 

 sonal occurrence and abundance of juveniles in near- 

 shore waters need further investigation. 



McCaffrey (1981) reported capture depths of 30-187 

 m for 23 specimens purported to be S. civitatium taken 

 on the continental shelf in the northeastern Gulf of 

 Mexico between 84°30' and 89°00'W longitudes. Nine- 

 teen of these specimens were collected between 80 and 

 187 m, depths considerably deeper than records for 

 specimens I examined. Not all specimens identified as 

 S. civitatium by McCaffrey were preserved and 

 curated in collections (at least nine were indicated as 

 having been discarded). One retained specimen (UF 

 70946) collected at 45 m, is S. civitatium, but two 



other specimens (UF 70885) from Tursiops Station 

 7019-07 with an estimated depth of 187 m are, rather, 

 S. pusillus (Goode and Bean) and an undescribed spe- 

 cies (species C of Munroe 1987), which occur common- 

 ly at depths similar to that reported for this station 

 (187 m). Given the complexity of the series identified 

 as .S. civitatium in McCaffrey's study, the very deep 

 captures reported (80-187 m) for S. civitatium are 

 probably erroneous. 



Remarks In the original description of S. civitatum, 

 Ginsburg (1951:198) stated that this species and S. 

 plagusia differed enough to consider them distinct 

 species but that it was possible that they represented 

 subspecies of a more widespread polytypic species. It 

 was shown earlier (see "Remarks" section in account 

 of S. plagusia) that Ginsburg had more than one species 

 in his account of S. plagusia, and therefore his sub- 

 specific designations for this species were unfounded. 

 Symphurus civitatium is consequently recognized as 

 a species within this complex of morphologically similar 

 species of Symphurus. 



The etymology of the name civitatum, applied by 

 Ginsburg to this species, is unclear from the original 

 description. The name may have been derived from the 

 genitive plural of civitas (meaning "of the citizenry"). 

 Following this assumption, the proper genitive plural 

 is civitatium, not civitatum as indicated by Ginsburg 

 (G.C. Steyskal, Dep. Entomology, Natl. Mus. Nat. 

 Hist., Wash. DC, pers. commun. 1989). Thus, the spell- 

 ing of the specific name for this species remains un- 

 changed regardless of generic assignment of the 

 species. Therefore, spelling changes such asS. civitatus 

 (Bailey et al. 1960, and other checklists of common and 

 scientific names) are incorrect. 



Comparisons Symphurus civitatium is most similar 

 to, but has a completely allopatric distribution from, 

 the Caribbean and South Atlantic species S. plagusia. 

 Differences between these two species were discussed 

 in the "Comparisons" section under the account for 

 S. plagusia. 



Meristic features of <S. civitatium overlap at least 

 partially those of two other Atlantic species belonging 

 to this complex (the Caribbean and South Atlantic 

 species S. caribbeanus and S. tessellatus). There is 

 almost complete overlap in several meristic features 

 between S. civitatium and S. caribbeanus; however, 

 S. civitatium has a fleshy ridge on the ocular-side lower 

 jaw (absent in S. caribbeanus; see Figures 4b and 4e) 

 and has lower modal counts for total vertebrae (47- 

 49 vs. 49-50 in S. caribbeanus), dorsal fin rays (86-93 

 vs. 89-96), and anal fin rays (70-78 vs. 74-80). Sym- 

 phurus civitatium also has narrow crossbands with 

 uniformly-colored fins (becoming progressively darker 



