Acryptolaria novaecaledoniae, Peña Cantero & Vervoort, 2010

Peña Cantero, Álvaro L. & Vervoort, Willem, 2010, Species of Acryptolaria Norman, 1875 (Cnidaria, Hydrozoa, Lafoeidae) collected in the Western Pacific by various French expeditions, with the description of nineteen new species, Zoosystema 32 (2), pp. 267-332 : 308-310

Acryptolaria novaecaledoniae n. sp.

( Figs 21 ; 30 ; 32E ; Table 22)

TYPE MATERIAL. — Loyalty Islands. MUSORSTOM 6, stn DW 422, 20°26.20’S, 166°40.31’E, 257 m, 16.II.1989, many stems up to 55 mm high, on coral. Of this lot 1 48 mm high colony, holotype (MNHN-Hy.2009-0169) ; 1 50 mm high stem, paratype ( MNCN 2.03 /426) ; the remaining colony and fragments, paratype (RMNH-Coel. no. 31522).

OTHER MATERIAL EXAMINED. — Loyalty Islands. MUSORSTOM 6, stn DW 398, 20°47.19’S, 167°05.65’E, 370 m, 13.II.1989, a few stem fragments up to 60 mm long (MNHN-Hy.2009-0204).

Norfolk Ridge. CHALCAL 2, stn DW 78, 23°41.30’S, 167°59.60’E, 233-360 m, 30.X.1986, 2 stems up to 35 mm high, on coral (MNCN 2.03/427).

SMIB 4, stn DW 51, 23°41.3’- 23°40.5’S, 168°00.6’- 168°00.7’E, 245-260 m, 9.III.1989, 2 fragments up to 25 mm long (MNHN-Hy.2009-0202). — Stn DW 53, 23°40.1’- 23°39.5’S, 167°59.9’- 168°00.3’E, 250-270 m, 9.III.1989, 2 stems and 2 fragments up to 47 mm high (MNHN-Hy.2009-0203).

SMIB 5 , stn DW 70, 23°40.6’S, 168°01.1’E, 270 m, 7.IX.1989 ,3 stems up to 24mm high ( MNCN 2.03 /428).— Stn DW 71, 23°41.3’S, 168°00.7’E, 265 m, 7.IX.1989, 1 stem c. 17 mm high (MNHN-Hy.2009-0205). — Stn DW 76, 23°41.2’S, 168°00.5’E, 280 m, 7.IX.1989, a few fragments up to 28 mm long (MNHN-Hy.2009-0206); a stem c. 15 mm high in slide ( MNCN 2.03 /400). — Stn DW 78, 23°40.8’S, 168°00.2’E, 245 m, 7.IX.1989, 3 fragments up to 7 mm long ( MNCN 2.03 /429). — Stn DW 101, 23°21.2’S, 168°04.9’E, 270 m, 14.IX.1989, 2 stems up to 30 mm high ( MNCN 2.03 /430) .

ETYMOLOGY. — The specific name novaecaledoniae refers to the New Caledonia region where it was found. The species name is a noun in female genitive.

ECOLOGY AND DISTRIBUTION. — Acryptolaria novaecaledoniae n. sp. was taken in the Norfolk Ridge area and near the Loyalty Islands, where it was collected at depths between 233 and 370 m. It occurred epibiotic on corals.

DESCRIPTION

Stems up to 60 mm high, strongly polysiphonic. Branching frequent (up to fourth-order branches observed) and irregular, but more or less in one plane ( Fig. 32E ), sometimes with anastomoses; branches straight ( Fig. 21A ).

Hydrothecae alternately arranged, approximately in one plane ( Fig. 21A ), mostly cylindrical ( Fig. 21 ); diameter only decreasing at their base. Hydrotheca strongly curved outwards, free part initially more or less perpendicular to adnate basal part, but eventually slightly turned upwards. As a consequence, the adcauline hydrothecal wall is convex in its adnate basal part and moderately concave in its free portion. Abcauline wall straight or slightly convex over basal third, followed by a strongly marked inflection point (sometimes forming a shallow embayment), to run straight or convex over its remaining length.Hydrotheca adnate for slightly over half of its adcauline length (adnate/free ratio 1.2); aperture circular, oblique, upwardly directed. Rim even, frequently with several short renovations ( Fig. 21A, D ).

Large nematocysts relatively small and bananashaped ( Fig. 30 ).

Coppinia not observed.

REMARKS Acryptolaria novaecaledoniae n. sp. is certainly close to A. inversa n. sp.; the nematocysts in both species are of the same size. Nevertheless, they are distinguishable by the degree of branching, that is scarce in A. inversa n. sp. and frequent in A. novaecaledoniae n. sp., but especially by the shape of the hydrothecae which in A. novaecaledoniae n. sp. are never directed downwards and are deprived of the peculiar abcauline hump so characteristic of A. inversa n. sp. Moreover, A. inversa n. sp. has longer hydrothecae with a much longer free proportion.

Figures

FIG. 21. — Acryptolaria novaecaledoniae n. sp.: A, branch fragment showing hydrothecal arrangement; B-D, hydrothecae; A, from MUSORSTOM 6 stn DW 422; B, from SMIB 5 stn DW 71; C, from SMIB 5 stn DW 101; D, from MUSORSTOM 6 stn DW 398. Scale bar: A, 600 μm; B-D, 250 μm.

FIG. 30. — Outline drawings of the large type nematocysts of Acryptolaria species discussed in the present report. Scale bar: 30 μm.

FIG. 32. — Colony shape and branching in Acryptolaria Norman, 1875: A, A. longitheca (Allman, 1877), from MUSORSTOM 6 stn DW 407; B, A. medeae n. sp., holotype,MUSORSTOM 4 stn CP 195; C, A. niobae n. sp., holotype,BIOCAL 1 stn DW 08; D, A. norfolkensis n. sp., holotype, BIOCAL 1 stn DW 36; E, A. novaecaledoniae n. sp., holotype, MUSORSTOM 6 stn DW 422; F, A. profunda n. sp., holotype, MUSORSTOM 6 stn DW 422; G, A. pseudoangulata n. sp., holotype, MUSORSTOM 4 stn CP 217; H, A. pseudoundulata n. sp., holotype, MUSORSTOM 6 stn DW 457; I, A. pulchella (Allman, 1888), from MUSORSTOM 3 stn DR 117; J, A. pygmaea n. sp., holotype, SMIB 4 stn DW 60; K, A. tetraseriata n. sp., holotype, MUSORSTOM 3 stn DR 117; L, A. undulata n. sp., holotype, BIOCAL 1 stn DW 66. Scale bars: A, C, F-I, 10 mm; B, D, E, K, 20 mm; J, L, 5 mm