Cionophora guillaumae Achituv, 2002

Achituv, Yair & Newman, William A., 2002, The barnacles of Astreopora (Cirripedia, Pyrgomatini / Scleractinia, Acroporidae): organization plans, host speci ® city, species-richness and geographic range, Journal of Natural History 36 (4), pp. 391-406 : 400-402

Cionophora guillaumae Achituv sp. nov.

(®gure 5B±I)

Material. Two dried specimens of the new species were removed from two colonies of Astreopora sp. housed in the coral collection of the MuseÂum National d’Histoire Naturelle, Paris. They are now housed with the crustacean collection.

HOLOTYPE: MNHN Ci 2803 (wall, opercular plates and part of coral) from sample`MR 9N’ Coll. no. 20000, Astreopora cf. listeri : J. P. Chevalier’s notebook, volume IV, p. 718: 28 October 1962 from Astreopora colony located on the leeward side of a coral knoll of a lagoonal reef, between 10 and 15 m depth, near Kouare Islet (= Ile Marmite) in the lagoon SW of the main island of New Caledonia, 22ss47¾ 20 ² S, 166ss47¾ 15 ² E.

PARATYPE: MNHN Ci 2804 (wall, right opercular valve and a piece of the coral), from sample`BP 26 W’ Coll. no. 20001, Astreopora myriophthalma : J. P. Chevalier’s notebook, volume IV, p. 627: collected 27 September 1962 from Astreopora colony located on the outer, windward reef, from the side of a coral patch between 4 and 12 m, NE coast of Art Island, Belep Islands (N of New Caledonia), 19ss39¾ 30 ² S, 161ss20¾ 30 ² E.

Etymology. Named for Mirreille Guillaume, MuseÂum National d’Histoire Naturelle, Paris, who kindly placed the material at our disposal.

Description. Small species (largest specimens 2.5 mm in rostro-carinal diameter); wall white, ovate in outline and slightly wider at rostral end, externally ¯at, with 11±14 rows of one to three pillars radiating from ori®ce (®gure 5B, C), valleys between rows U-shaped (®gure 5D). Rostro-carinal diameter of wall proportionatel y large, r±c diameter of oval ori®ce slightly more than one-third that of wall. Growth lines of sheath occupying about half its internal surface of wall; smooth surface of sheath with a pair of ridges at rostral end (®gure 5H) demarcating bosses accommodating expanded limbus adductorum of each opercular plate. Radial (= longitudinal) septa of wall with coarsely denticulate peripheral edges that ®t into longitudinal grooves of basis, primary radial septa capped by the rows of radial pillars formed by outer lamella of the wall. Each marginal cavity, bounded by radial septa and outer lamina and sheath, is subdivided by a longitudinal transverse septum, and small secondary radial septa may begin on them (®gure 5D).

Scutal portion of opercular plates (®gure 5E±G) elongated; external growth ridges thin, condensed, curving in and out of the partially closed spur furrow. External portion of rostral end, representing about one-third length of each plate and covered by sheath, has a curving row of external denticles and pits, and a small internal notch between rostral angle and internal rostral tooth. Thin adductor ridge (limbus adductorum) extends well below basal margin of the plate while tergal portion supports a long, narrow spur with a deep spur furrow, the median portion of which is closed. A possible trace of external suture between tergal and scutal portions can be seen on one of the plates (®gure 5G), but it is more central than expected and could have resulted from damage to lower margin of plate early in development.

When wall is viewed from within, rostral to the bosses for adductor ridges (®gure 5H), a median and two lateral septa can be seen extending beyond margin of the sheath on to outer lamella. Medial to lateral pair, on surface of sheath, there is a pair of low ridges forming rostral margins of the bosses. These join next pair of lateral septa extending to outer lamella. In small individual, the pair of shallow grooves, delimiting these ridges rostrally, approximate position of original pair of sutures between rostrum and lateral plates in Hiroa (cf. ®gure 2C), but in larger (older?) of two specimens these grooves are not well marked. Whether their position is reminiscent of sutures or simply coincidental could not be ascertained.

Basis (®gure 5I) white, solid, long and tapering especially towards bottom, with longitudinal grooves to accommodate marginal teeth of radial septa of wall separated by an in-bowing of basis that leaves external, longitudinal passages for coral tissue between basis and skeleton of the coral.

Comparison with Cionophora soongi

Cionophora soongi was recently described as a new genus and species from Taiwan where it co-occurs with Hiroa stubbingsi on Astreopora sp. ( Ross and Newman, 1999). The opercular plates of Cionophora guillaumae , the new species from near New Caledonia, diVer from it in the following characters: (1) an internal notch between the external rostral end and the rostral tooth, (2) the proportion of the height of the limbus adductorum to the exposed portion of the plate substantially less (ratio 0.5 versus 0.7±0.75), (3) the basal margin being less sinusoidal, and (4) with regard to the wall, fewer radiating rows of pillars.