Hanleya nagelfar Kaas and Van Belle 1985

Hanleya nagelfar (Lovén, 1846)

(Figures 9–19)

Hanleya nagelfar Kaas and Van Belle 1985: 196, Figure 92, map 19 (synonymy); Waren and Klitgaard 1991: 51, Figures 1–6; Dell’ Angelo et al. 1998: 244, PL 1, Figure 10.

Lectotype, NHRM, type collection 1329 (designated by Kaas and Van Belle (1985)).

Finnmark, Norway.

Barents and Norwegian Seas: R/V Andrey Pervozvaniy, 1899, stn 4, 70.0230° N, 31.49° E, 144–178 m, 2 spms; stn 38, 69.58° N, 32.40° E, 230 m, 1 spm; 1900, stn 102, 74.27° N, 22.04° E, 180–211 m, 1 spm (Table 2, No. 8); stn 462, 71.20° N, 33.30° E, 304– 280 m, 1 spm; stn 464, 71.21° N, 3159° E, 268 m, 1 spm. R/V Persey, 1924, stn 228, 70.3030° N, 31.13° E, 175 m, 1 spm (Table 2, No. 10); 1927, stn 677, 69.31° N, 34.39° E, 173 m, 1 spm; 1935, stn 3337, 71.35° N, 31.464° E, 313 m, 1 spm (Table 2, No. 11).

R/V SRT4225, cruise 1, 1955, stn 38/104, 61.308° N, 04.166° E, 300 m, 1 spm. R/ V Sevastopol. RT-97, cruise 8, 1958, Lofoten Ids., 68.08° N, 13.50° E, 1 spm (Table 2, No. 7); cruise 9, 1958, stn 1453, 62.002° N, 6.146° W, 112 m, 1 spm; stn 1488, 72.291° N, 23.072° E, 335 m, 2 spms. R/ V Maslov, cruise 5, 1969, stn 180/201, 70.40° N, 17.275° E, 510 m, 1 spm; stn 182/203, 71.30° N, 16.46° E, 300 m, 1 spm (Table 2, No. 13); stn 183/204, 72.02° N; 17.02° E, 360 m, 1 spm (Table 2 No. 12); stn 188/209, 73.20° N, 15.25° E, 500 m, 1 spm. R/ V Tunets, cruise 105, 1978, stn 4, 70.06° N, 32.325° E, 230 m, 1 spm; stn 11, 70.110° N, 17.350° E, 225 m, 2 spms; stn 12, 70.330° N, 16.540° E, 1100 m, 5 spms. R/ V Dalnie Zelentsi, cruise, 16.1982, stn 64, 67.559° N, 10.080° E, 280 m, 3 spms. F.D. Behrens, 1948, Lofoten, 2 spm (ZIM). F.D. Saturn, 1958, 64.44° N, 35.06° W, 500 m, 1 spm. (ZIM); 1923, Folden, 50–100 m, 1 spm, (TM 13350); Skattora, Tromso, 54 m, 2 spms, (Table 2, No. 5), (TM 12923); 1951, Senja, Steinavar, 360–365 m, 1 spm, (TM 13335); 1954, Morsdalsfjord, 50–110 m, 1 spm, (TM 13196); 1954, Balsnes, 28 m, 1 spm, (TM 13258); 1954, Brokskar, Rystr, 50–120 m, 1 spm (Table 2, No. 3), (TM 12962); Beiarn, 40–90 m, 1 spm, (TM 13237); 1955, Tjelsund, 60–110 m, 1 spm, (TM 12955); 1955, Holandsfjord, 45–770 m, 1 spm, (TM 13241); 1955, Eiet, 52–58 m, 6 spms, (TM 13001); Masoy, 125– 90 m, 2 spms, (TM 13299); 1955, Bjarandfjord, 76–92 m 1 spm, (TM 12997); 1955, Rana, 35–42 m, 1 spm, (TM 13304).

Eastern Greenland Sea: R/ V Atlantida, cruise 10, 1973, stn 18/1668, 74.50° N, 16.00° E, 360 m, 1 spm.

Southeastern Greenland: R/ V Sevastopol, RT-97, cruise 5, 1957, stn 1168, 66.162° N, 31.356° W, 345 m, 2 spms; stn 1609, 65.526° N, 29.586° W, 425 m, 1 spm.

Central and North Atlantic Ocean: R/ V Akademik Keldysh, cruise 4, 1982 stn 513, 34.261° N, 30.030° W, 690 m, 1 spm; stn 444, 58.208° N, 31.363° W, 1635– 1535 m, 1 spm; stn 364, Reykjanes Ridge, 1330 m, 1 spm; st. 385, Reykjanes Ridge, 1680– 1800 m, 1 intermediate valve; R/ V Ichtiandr cruise 8, 1982, stn 39, 09.038° N, 21.101° W, 610–700 m, 1 spm; stn 50, 33.141° N, 29.425° W, 700–740 m, 1 spm.

Newfoundland Bank: R/V Sevastopol, RT-97, cruise 16, 1960, stn 2805, 49.477° N, 50.185° W, 318–324 m, 1spm; R/V Nereida, 2009, cruise 0509, stn 6, cod 5, 48.2915° N, 44.0609° W, 1348 m, 1 spm; stn 10, cod 54, 48.0005° N, 43.7607° W, 1554 m, 1 spm; stn 12, cod 16, 47.7772° N, 43.5748° W, 1462 m, 1 spm; stn 19, cod 21, 47.1643° N, 43.5338° W, 1358 m, 2 spms (Table 2, No. 4), stn 22, cod 12, 46.8400° N, 43.6404° W, 956 m, 1 spm (Table 2, No. 6); stn 23, cod 22, 46.7749° N, 43.8651° W, 1127 m, 3 spms; stn 24, cod 27, 46.6942° N, 43.9686° W, 1104 m, 1 spm; 2010, cruise 0610, stn 63, cod 8, 46.3697° N, 44.9944° W, 1406 m, 2 spms; stn 67, cod 7, 46.2677° N, 46.5429° W, 613 m, 1 spm; stn 69, cod 10a, 46.1543° N, 46.4503° W, 502 m, 1 spm; stn 69, cod 10c, 46.1543° N, 46.4503° W, 502 m, 2 spms; stn 71, cod 10, 46.0800° N, 46.3421° W, 888 m, 1 spm; cruise 0710, stn 75, cod. 24, 45.8692° N, 46.8210° W, 1227 m, 1 spm (Table 2, No. 1); stn 96, cod. 30, 43.9894° N, 48.9512° W, 863 m, 1 spm; cruise 0810, stn 99, cod 11, 43.6147° N, 49.0781° W, 548 m, 1 spm; stn 100, cod 12, 43.4844° N, 49.1855° W, 694 m, 2 spm; stn 103, cod 20, 429433° N, 49.5621° W, 1154 m, 1 spm. FN3L, 2006, stn 2, 47.9415° N, 47.3725° W, 411 m, 1 spm; FN3L, 2006, stn 9, 47.9370° N, 47.1883° W, 460 m, 1 spm; FN3L, 2008, stn 37, 47.6480° N, 47.1340° W, 503 m, 2 spms; FN3L, 2008, stn 84, 46.4488° N, 47.2603° W, 396 m, 1 spm; FN3L, 2009, stn 89, 461100° N, 47.3333° W, 1005 m, 2 spms; PLA, 2008, stn 98, 43.6298° N, 48.9907° W, 1436 m, 4 spms (Table 2, No. 9).

North America: Off Eastport, Maine (Jeffreys coll.), 1 spm, (USNM, 177511); Off Martha’ s Vineyard, Massachussetts, 1 spm, (USNM); Georges Bank, 270 m, 1 spm (USNM); Nova Scotia, 72 m, 1 spm (USNM).

North and Central Atlantic Ocean, the Barents, Norwegian and Greenland seas, near southern Greenland, North America, Europe and northern Africa, on Mid-Atlantic Ridge from 74.27° N to 09.038° N at depths from 28 to 1680 m, mostly deeper than 200 m.

Large specimens of Hanleya nagelfar are easily distinguished from H. hanleyi (see Kaas and Van Belle, 1985), but small chitons (<10 mm) are difficult to identify.

In order to study age variability in H. nagelfar, seventeen specimens of different sizes (BL = 5.0–73.0 mm), from different regions of the Atlantic Ocean were measured (Table 2, Figures 8–18). These measurements revealed that important changes occur in the shape of the valves, the thickness of the girdle, and the shape, size and ribbing of the dorsal spicules of the girdle.

With increasing body length, the ratio of head valve width/tail valve width decreased from 1.27 (BL = 5.0 mm) to 0.84 (BL = 70.0 mm); the ratio of valve V width/valve V length decreased from 2.56 (BL = 5.0 mm) to 1.36 (BL = 70.0 mm); and the ratio of valve V width/width of adjacent girdle also decreased from 5.9 (BL = 5.0 mm) to 1.36 (BL = 70.0 mm) (Table 2).

Small and medium size specimens (BL = 5.0–29.0 mm) have flattened, short and pointed spicules with 6–7 ribs arranged around the spicule (Figures 10A, C, 12A, B, 14A, C, D, E, 16A–C, 17D, 18A, C). With increasing age (specimen size) the spicules become longer and the ribs become less prominent or obsolete (Figures 18B, D, 19E).