Chiridota pisanii Ludwig, 1886

Chiridota pisanii Ludwig, 1886 View in CoL

Table 2

Chiridota purpurea . —Théel, 1886: 15, pl. 2 fig. 1 (= Chiridota pisanii Ludwig, 1886 View in CoL ; non Holothuria ( Fistularia) purpurea Lesson, 1830 ; see Ludwig 1898). (For complete synonymy see Bohn in Altnöder et al. 2007).

Material examined. S Atlantic Ocean, Burdwood Bank, ICEFISH 2004 stn 1–OT1, 54.22°S 59.84°W, 93 m NMV F106959 About NMV (1) GoogleMaps ; ICEFISH 2004 stn 1–OT2, 54.22°S 59.83°W, 93 m NMV F106963 About NMV (4) GoogleMaps ; Patagonia, 52°12'S 67°19'W, 95 m, Discovery Expedition, William Scoresby stn 750, 19 Sept 1931, NHM 2010.110 (1, wheel cluster only) GoogleMaps ; Argentina, Tierra del Fuego, 54º00'S 67º24'W, 0 m, 1999, NMV F86016 About NMV (2) GoogleMaps ; Cape Horn, 56°20'S 67°10'W, 121 m, Discovery Expedition, William Scoresby stn 388, 16 Apr 1930, NHM 2010.111 GoogleMaps (1).

Diagnosis (from Bohn in Altnöder et al. 2007). Up to 68 mm long ( 130 mm in Ludwig 1898); tentacles 12, 4–7 pair of digits per tentacle, longest distally, tentacle rods with variably branched ends, sometimes central hub, 16–69 µ m long; calcareous ring with 5 radial 7 interradial plates, all radial plates perforated for passage of nerve; polian vesicles 4–11 (– 16 in Théel 1886); single ciliated urns at base of mesenteries, numerous in mid-dorsal and left dorsal interradius, sparse in right ventral interradius; chiridotid wheels with serrations on inner side continuous, gathered into papillae in single series in dorsal interradii, inconspicuous or lacking in ventral interradii, 43–147 µ m diameter; miliary granules in longitudinal muscles 14–49 µ m long.

Colour (preserved). Off-white to pink to reddish-brown.

Distribution. Pacific and Atlantic coasts of southern South America (south of 42ºS), Falkland Is, 0–102 m (Bohn in Altnöder et al. 2007); Burdwood Bank, 93 m (this work); Cape Horn, 121 m (this work).

Remarks. Chiridota pisanii Ludwig has not been reported south of the Polar Front, and is not an Antarctic species. Bohn (in Altnöder et al. 2007) has provided a comprehensive systematic treatment with illustrations. He queried the identity of the Challenger Falkland Is specimens determined by Théel (1886) as Chiridota purpurea , and subsequently judged by Ludwig (1898) to be Chiridota pisanii , since the wheel sizes were larger (140–160 µ m diameter) than his measurements for Chiridota pisanii (43–147 µ m diameter). Our ossicle measurements for Burdwood Bank specimens are: wheels 80– 144 µ m diameter; tentacle rods 48–80 µ m long.

O’Loughlin (2002) initially failed to find hook ossicles in specimens from Heard I. and identified them as Chiridota pisanii . Hook ossicles were subsequently found, and the material re-determined as Taeniogyrus contortus (see O’Loughlin 2009).