DISTRIBUTION: Southern side of Cape Cod to North Carolina 

 (Bousfield 1973): Gulf of Florida from Tampa north (Bousfield).' 2 



HABITAT: Kinner et al. (1974) reported this species to dominate 

 a transitional zone between sand and mud in Delaware Bay. Bous- 

 field (1973) reported it to be abundant in coarse sand from low 

 intertidal to depths of about 50 m. Ampelisca verrilli was the sec- 

 ond most abundant amphipod collected in the New York Bight 

 apex, most commonly found in fine sands with some occurring in 

 medium sands off Long Island and New Jersey. This species was 

 present only in low organic areas in depths to 24 m (Fig. 58; Table 

 1). 



FEEDING ECOLOGY: Ampelisca spp. lie upside down in their 

 tubes, projecting their setose antennae as filtering organs (Barnard 

 1969). Ampelisca verrilli has been classified as a suspension 

 feeder-surface detritivore (Bousfield). 1 ' 



REPRODUCTION AND GROWTH: Bousfield (1973) stated 

 that A. verrilli has an annual life cycle in New England, with ovi- 

 genous females present in the summer. However, in a west Florida 

 estuary. Thoemke (1977) found ovigerous females to be present 

 year-round, averaging 9.6% of the population. He believed them to 

 produce several broods per year. In view of these differences, tem- 

 perature may be of importance in regulating the life cycle of this 

 species. 



In this family (Ampeliscidae). the mature male form emerges in 

 abrupt metamorphosis from a femalelike penultimate stage (Bous- 

 field 1973). 



Unciola irrorata Say, 1818 



DESCRIPTION: Smooth, slender, slightly depressed body with 

 red spots or blotches when alive. Females grow to 10 mm. males to 

 13 mm. Unciola irrorata usually inhabits tubes constructed by 

 other amphipods or polychaetes, but can build a tube of its own if 

 no others are available (Bousfield 1973). Smith (1950) reported 

 that these amphipods have been observed swimming or roaming 

 across the bottom, leaving their tubes for considerable lengths o\ 

 time. 



DISTRIBUTION: Gulf of St. Lawrence to Cape Hatteras (Bous- 

 field 1973): off South Carolina (Shoemaker 1945): also. Green- 

 land. Norway (Holmes 1905). 



HABITAT: Pratt (1973) and Maurer et al. (1976) included U. 

 irrorata as a member of the silty sand fauna of the Middle Atlantic 

 continental shelf and estuaries. Bousfield (1973) reported it to be 

 found in coarse to medium sands from the lower intertidal to over 

 55 m in New England waters. Shoemaker ( 1945) recorded the spe- 

 cies in depths to 283 m. Holmes (1905) recorded it to over 914 m 

 and Schmitz (1959) 14 reported U. irrorata from muddy bottoms in 

 North Carolina to depths of 1.500 m. Pearce (1972) found U. 

 irrorata to be the only amphipod collected in the sewage sludge dis- 

 posal area of the New York Bight apex. Michael (1973) called U. 

 irrorata a cold water species which tolerates a v. ide range of sedi- 

 ment types, but prefers sand. The present collections in the Bight 



'■'/ l40°30'- 



i 40 20- 



4010 



i: Edward Bousfield. pers. commun.. cited by Fox and Bynum ( I975). 

 "Edward Bousfield. pers commun., cited by Biernbaum (1979). 

 l4 Schmitz. E. 1959. A key to the marine Amphipoda of the Beaufort. North Caro- 

 lina area. Unpubl. manuscr., 6 p. Duke Marine Laboratory. Beaufort. N.C. 



Figure 59. — Distribution and abundance of Unciola irrorata in the New York 

 Bight apex. 



apex show U. irrorata to occur in all grades of sand, particularly in 

 fine sand and in low organic areas. Unciola irrorata was wide- 

 spread in the apex, the third most abundant amphipod collected, 

 occurring in depths to 33 m (Fig. 59; Table 1). 



FEEDING ECOLOGY: Smith (1950) reported U. irrorata to be 

 a scavenger and detritus feeder, while Sanders (1956) classified it as 

 a selective deposit feeder, which may feed on detritus or be herbivo- 

 rous. Enequist (1949) reported members of this family to be pri- 

 marily filter feeders, emerging from their tubes and feeding on 

 detritus whenever concentrations of suspended material are low. 



Unciola irrorata is a principal forage species for haddock col- 

 lected off Cape Cod and Georges Bank (Wigley 1956: Wigley and 

 Theroux 1965). 



REPRODUCTION AND GROWTH: Bousfield (1973) reported 

 an annual life cycle off New England, with ovigerous females 

 present from March to July: one brood per female. Smith (1950) 

 stated that U. irrorata breeds 10-1 1 mo of the year in Block Island 

 Sound, with mid-summer the minimal spawning season. 



Pseudunciola obliquua (Shoemaker, 1949) 



DESCRIPTION: Body smooth, slender, lacking eyes: length to 6 

 mm (Bousfield 1973). 



DISTRIBUTION: Bay of Fundy to New Jersey (Bousfield 

 1973). 



40 



