We describe the most frequently collected Calcarea from the New Caledonia lagoons and adjacent coral reefs. We have identified ten species (six Calcinea and four Calcaronea), two of which have already been reported for New Caledonia. Five species are new to science: the Calcinean species Clathrina chrysea n. sp. and Leucascus neocaledonicus n. sp., and the Calcaronean species Sycettusa tenuis n. sp., Vosmaeropsis hozawai n. sp. and Leucascandra caveolata n. gen., n. sp. The latter, which is very frequent in the studied region, belongs to the newly described genus Leucascandra characterized by a complex cormus composed of copiously branched thin tubes. These tubes have a thin wall supported by the atrial and cortical skeletons, containing an inarticulate choano-skeleton composed of subatrial spicules only. The species already described, Leucetta chagosensis, Leucetta microraphis, Pericharax heteroraphis and Sycon gelatinosum, belong to the Indo-Pacific tropical region fauna, have been frequently observed and described, probably due to their large size and bright colours.
Porifera, Calcarea, Pacific Ocean, New Caledonia, Coral reef fauna.