124 



D.G. REID AND C. OSORIO 



black coloration of the animal suggest C. fecunda, although the 

 shells are frequently white as in C. dilatata. At station 12 it was 

 found that specimens from beneath rocks had white, circular shells 

 and lightly-pigmented, predominantly yellow animals, whereas those 

 from the sides of rock pools had purple, oval shells and black 

 animals; it is not known whether these forms represent the two 

 species. Gallardo (1979) noted that the two were often sympatric in 

 the fjords of southern Chile, but that C. dilatata was the more 

 common. Large shells were moderately common in the ancient shell 

 middens on Isla Traiguen. 



Trochita trochiformis (Born, 1778) 



(Figure 3H, I) 



Turbo trochiformis Born, 1778: 355. 



Calyptraea (Trochita) trochiformis - Keen, 1971: 456, fig. 804. 



Marincovich, 1973: 31-32, fig. 65. 

 Trochita radians (Lamarck, 1822) - Rehder, 1943: 42-43, fig. 1 



(synonymy). 



Description. Shell to 54 mm; circular with central apex; sculp- 

 ture of numerous sharp radial ribs; colour white, internally white 

 stained with dark brown; animal unpigmented. 



Habitat. Attached to undersides of stones closely appressed to 

 silty sediment in large tidal pool, in sublittoral fringe, sheltered from 

 wave action, common (station 14); also under stones on moderately 

 exposed rocky shores. In the north of Chile this species lives on 

 wave-exposed coasts (Marincovich, 1973), on both intertidal and 

 subtidal rock substrates (Cafiete & Ambler, 1992). 



Records. Stations 12, 14. Elsewhere Manta (Ecuador) to 

 Valparaiso (Rehder, 1943;Keen, 1971)andCanalChacao(41°50'S; 

 Brattstrom & Johanssen, 1983). The present records extend the 

 confirmed range of this species. In addition, it has been mentioned 

 from Tierra del Fuego and the Magellan Strait (Carcelles & 

 Williamson, 1951), but confusion with the Magellanic species T. 

 pileus (Lamarck) is likely. Range: 1— 46°S. 



Remarks. The worldwide distribution of the five recognized 

 living Trochita species shows a strong association with cold upwelling 

 systems or (in the Magellanic T pileus) with cold currents (Taylor & 

 Smythe, 1985). The present records extend the distribution of T. 

 trochiformis considerably beyond the upwelling zones on the Chil- 

 ean coast, which extend only to 41°S (Brattstrom & Johanssen, 

 1983). Another peculiarity of these records is the unexpectedly 

 sheltered microhabitat under stones, and even resting on silt. Else- 

 where, this and the two most closely related species, T spirata 

 (Forbes) and T dhofarensis Taylor & Smythe, are found in the low 

 eulittoral and shallow sublittoral on rocky coasts exposed to strong 

 wave action (Marincovich, 1973; Taylor & Smythe, 1985; D.G. Reid 

 pers. obs. in Mexico and Cabo Verde). The intracapsular develop- 

 ment of T. trochiformis has been described by Cafiete & Ambler 

 (1992). This edible species was occasionally found in shell middens 

 on Isla Traiguen. 



mm (to 19mm,Strebel, 1 906); shell fragile, transparent, auriculiform 

 with small, low spire and enlarged, oval aperture; shell entirely 

 covered by smooth mantle with oval outline and anterior notch, 

 broadly overlapping the foot; in life mantle is orange yellow with 

 indistinct dark markings; penis with conspicuous lateral flange and 

 small terminal filament. 



Habitat. Single animal dredged from 10-15 m, on bottom of silt 

 with scattered pebbles. Dredged from 40 m in Beagle Channel 

 (Linse, 1997). 



Records. Station 25. Elsewhere Beagle Channel (Strebel, 1906: 

 Linse, 1997). Range: 46-55°S. 



Remarks. The identification of this single specimen is tentative, 

 and based on the form of the shell. Of the four species illustrated by 

 Strebel (1906) and one by Smith (1881), L. ampla is the only one 

 with a low-spired auriculiform shape as in the present example. 

 However, the form of the penis is somewhat different from that 

 outlined by Strebel (1906: pi. 11, fig. 70C). Marcus (1959: 85-86) 

 listed the names of 12 lamellariids reported from Chile and noted 

 that many were poorly known anatomically; this remains true and a 

 thorough revision is necessary. Members of the genus Lamellaria 

 prey upon ascidians. 



Family RANELLIDAE 



Argobuccinum (Argobuccinum) pustulosum ranelliforme 



(King & Broderip, 1832) 



(Figure 3M) 



Triton ranelliformis King & Broderip, 1832: 347. 



Argobuccinum ranelliforme - Smith, 1970: 462^166, pi. 39, figs 2, 



4, 6, 9, pi. 40, figs 2, 6. 7, 10-12, textfigs 2b, 5. 

 Argobuccinum (Argobuccinum) pustulosum ranelliforme - Beu, 



1985a: 56. 

 Argobuccinum (Argobuccinum) argus - Carcelles, 1954: 244-246, 



figs 5, 6 (not Gmelin, 1791, which is the nominate subspecies). 



Description. Shell to 82 mm; whorls rounded, two indistinct 

 varices per whorl; sculptured by low spiral ribs intersecting with 

 weak axial ribs to produce beaded sculpture, most pronounced on 

 spire whorls, becoming obsolete on last 1-2 whorls; colour cream 

 with chocolate brown ribs, interior white. 



Habitat. Common on beds of Mytilus in mid to low eulittoral 

 zone, and in zone of coralline red algae in sublittoral fringe, on 

 shores of moderate to strong wave exposure. 



RECORDS. Stations 5, 14, 17. Elsewhere Caldera to Tierra del 

 Fuego (Carcelles, 1954; Smith, 1970). Range: 27-55°S. 



Remarks. This is a large, edible species, of which 277 tonnes 

 were collected nationally in 1997 (SERNAP, 1998). The diet con- 

 sists of crustaceans and echinoids (Smith, 1970), and the egg 

 capsules of the nominate subspecies from South Africa have been 

 described (Kilburn & Rippey, 1982: 75-76). 



Family LAMELLARIIDAE 



Lamellaria ampla Strebel, 1906 



Lamellaria ampla Strebel, 1906: 145-146, pi. 11, figs 70, 71. 

 Castellanos, 1990: 27, pi. 1, figs 9, 10. 



Description. Animal 12 mm (to 32 mm, Strebel, 1906), shell 9 



Family CERITHIOPSIDAE 



Eumetula pulla (Philippi, 1845) 

 (Figure 7D) 



Cerithium pullum Philippi, 1845: 66-67. Strebel, 1905b: 652-655, 



pi. 23, fig. 40a-d. 

 Ataxocerithium pullum - Powell, 1951: 111-112, fig. I, no. 34 



