Checklist of recent brachiopod species collected during the Terrasses and Exbodi cruises in the New Caledonian region, SW Pacific

Abstract Twenty species belonging to 16 genera, i.e. Neoancistrocrania, Novocrania, Basiliola, Basiliolella, Ebiscothyris, Stenosarina, Kanakythyris, Xenobrochus, Terebratulina, Eucalathis, Fallax, Frenulina, Septicollarina, Campages, Annuloplatidia, and Thecidellina have been identified in the material collected during the Terrasses and Exbodi cruises in the New Caledonian region, SW Pacific. The species Basiliolella grayi (Woodward, 1855) and Fallax neocaledonensis Laurin, 1997 are the most common in the studied collection, while Eucalathis murrayi (Davidson, 1878) is reported for the first time from the New Caledonian region.


Introduction
The New Caledonia Exclusive Economic Zone, comprising the area from Vanuatu to Chesterfield Islands, is one of the most intensively investigated regions in the Indo-West Pacific Province; more than 40 oceanographic expeditions have been organized by French institutions within the programme Tropical Deep-Sea Benthos (formerly Musorstom; see also Bouchet et al. 2008). Brachiopods collected in this region have been described in many publications (e.g. d 'Hondt 1987;Laurin 1992Laurin , 1997Bitner 2007aBitner , 2009Bitner , 2010Bitner , 2011Bitner et al. 2008;Bitner and Cohen 2015).

Family Craniidae Menke, 1828
Neoancistrocrania norfolki Laurin, 1992 Fig. 2A-B This species, represented only by young individuals, was found only in two Exbodi stations at depths of 388-520 m. N. norfolki differs from other craniids by its massive ventral valve and internally by two erect divergent processes on the dorsal valve (Laurin 1997;Bitner 2009). Originally described from the Norfolk Ridge (Laurin 1992), it seems to be restricted to the Western Pacific (Cohen et al. 2014).

Novocrania sp.
The second craniid brachiopod is very rare and too poorly preserved to permit identification to species level. It was found in two stations (600-802 m). Morpho-species identification of Novocrania is uncertain and previous specimens from the region of New Caledonia have been described as N. reevei Lee & Brunton, 1986(see Bitner 2010. In the opinion of Robinson and Lee (2011) this is a synonym of N. japonica (Adams, 1863).

Family Basiliolidae Cooper, 1959
Basiliola beecheri (Dall, 1895) Fig. 2G-H This is one of three rhynchonellide species recognized in the studied material. B. beecheri is relatively common, found in 10 samples, with a depth range of 400-990 m and was already reported from the New Caledonian region (Laurin 1997;Zezina 2005;Bitner 2009). It also occurs in the Hawaii and Fiji regions (Dall 1895;Bitner 2006bBitner , 2008. Fig. 2C-D This species, already noted from New Caledonia (Laurin 1997;Bitner 2009), is rare, being found in 5 stations. Its depth range in the studied area is 300-510 m. Originally described from off Japan (Hatai 1940), B. lucida also occurs in the Fiji region (Bitner 2008). Fig. 2E-F This is one of the most common species (nearly 500 specimens). It was found in 13 Terrasses stations and 12 Exbodi stations (see Appendix), with a depth range of 150-584 m. Basiliolella grayi is restricted to the SW Pacific (Laurin 1997;Logan 2007;Bitner 2009 Bitner and Cohen (2015), is common only in the material collected during the Exbodi cruise. Its depth range is very great, from 70 to 1180 m. Externally, E. bellonensis is very similar to Abyssothyris wyvillei (Davidson, 1878), but it differs internally in the character of the loop; in A. wyvillei the loop has a narrow, anteriorly convex transverse band (see Cooper 1983;Bitner 2006bBitner , 2008, while in E. bellonensis the transverse band is broad and medially folded. Molecular analysis confirms this separation (Bitner and Cohen 2015).

Stenosarina crosnieri (Cooper, 1983) Fig. 3O-P
This short-looped terebratulide is a relatively common species in the investigated material, being already recorded from New Caledonia (Laurin 1997;Bitner 2009). About 50 specimens were found in 17 stations, with a depth range of 340-951 m. S. crosnieri was originally described from the south-western Indian Ocean (Cooper 1983).

Stenosarina globosa Laurin, 1997
The second Stenosarina species in the studied material is much rarer, being found in only five samples (386-570 m). Stenosarina globosa is smaller than S. crosnieri and characterized by a strongly convex shell. So far known only from the New Caledonia area (Laurin 1997), this species can be considered as endemic to this region. Laurin, 1997 Fig. 3M-N This species is very characteristic with its thick shell, strongly incurved beak and very small foramen. It is relatively rare, being found in six samples (150-510 m). It is known only from the New Caledonian region (Laurin 1997;Bitner 2009) and can be regarded as endemic to this area.

Fig. 3A-B
A single specimen of this species was found in one Terrasses station at 150-180 m but it was earlier recorded from New Caledonia (Laurin 1997;Bitner 2010). X. africanus was originally described from South Africa (Cooper 1973).

Xenobrochus indianensis (Cooper, 1973) Fig. 3C-D
This second species of Xenobrochus is also very rare, found in one Exbodi station at a depth of 388 m. Laurin (1997) already noted this species from New Caledonia. It was originally described from South Africa (Cooper 1973). Xenobrochus indianensis can be distinguished from X. africanus by a more convex shell, incurved beak with a partly concealed symphytium, and internally by the presence of a distinct cardinal process (Cooper 1973(Cooper , 1983Laurin 1997).

Family Cancellothyrididae Thomson, 1926
Terebratulina pacifica Yabe & Hatai, 1934 Fig. 4D This is a relatively common species, found in 12 stations (180-790 m). Its presence in the studied area was already noted (Laurin 1997;Bitner 2009), and it is common off Japan (Hatai 1940). This wide distribution suggests that a careful molecular analysis of a wide range of Pacific Ocean samples might lead to the recognition of multiple forms that have not been distinguished morphologically (e.g. Lüter and Cohen 2002).

Family Chlidonophoridae Muir-Wood, 1959
Eucalathis murrayi (Davidson, 1878) Fig. 4A-C This species is very rare and was found in only two Exbodi stations (388-802 m). Although known from the nearby New Zealand region (MacFarlan et al. 2009), this is the first report of E. murrayi from the vicinity of New Caledonia. Originally described from off the Kermadec Islands (Davidson 1880) it has a wide distribution in the south-western Pacific (Bitner 2006a) and is known from the western Indian Ocean (Zezina 1987).  So far the only representative of the family Chlidonophoridae reported from New Caledonia has been Eucalathis rugosa Cooper, 1973(see Laurin 1997Bitner 2009Bitner , 2010, which is characterized by strong ornamentation of single, coarse ribs, while in E. murrayi ribs are numerous, finer, and bifurcating. DNA sequences of these species have not yet been compared (B.L. Cohen, pers. communication).

Family Aulacothyropsidae Dagys, 1972
Fallax neocaledonensis Laurin, 1997 Fig. 4J-K This long-looped brachiopod is one of the most common (more than 250 specimens) and was identified in 20 stations (260-840 m). F. neocaledonensis was originally described from New Caledonia by Laurin (1997;see also Bitner 2009) and was also recognized in material from Fiji (Bitner 2006b(Bitner , 2008. Fig. 4H-I This rare species was found in one station of each cruise (680-802 m). Originally described from the Norfolk Ridge (Bitner 2009) it was also identified around Fiji and French Polynesia (Bitner 2008(Bitner , 2014.

Family Frenulinidae Hatai, 1938
Frenulina sanguinolenta (Gmelin, 1791) Fig. 4F-G This easily recognizable species was found in 20 stations but was abundant only in the Exbodi material where it appears to have a very wide bathymetric range (110 to 1100 m). However this range probably is the result of the wide depth-range of the DW3932 dredge haul (500 to 1100 m), the specimens of this generally shallow-water form probably having been collected only in the shallower water.

Family Dallinidae Beecher, 1893
Campages mariae (Adams, 1860) Fig. 4E In the studied material this species was found in 16 stations in the material of both cruises at depths of 180-790 m. Originally described from off Japan (Hatai 1940), C. mariae occurs in the Western Pacific (Logan 2007;Bitner 2009Bitner , 2010. Fig. 5F-J This species was originally described from the Norfolk Ridge where it was very common (see Bitner 2009). Here, A. richeri is rare, found in one Terrasses station and two Exbodi stations (622-802 m). It is characterized by numerous, transversely elongate pustules that cover the ventral valve (Fig. 5H-J). A. richeri can be treated as endemic to the New Caledonian region as it has not yet been recognized in other areas.

Annuloplatidia curiosa Bitner, 2014 Fig. 5K-L
This species is very rare, found in only one Exbodi station at depths of 400-520 m. It was already reported from New Caledonia by Laurin (1997), but was wrongly assigned by him to Megerlia echinata (Fischer & OEhlert, 1890) (see discussion in Bitner 2014: 256). It has a very wide distribution, being known from New Zealand, Wallis and Futuna Islands, and French Polynesia (Bitner 2007b(Bitner , 2008(Bitner , 2014.

Family Thecidellinidae Elliott, 1953
Thecidellina maxilla (Hedley, 1899) Fig. 5A-E This is the only thecideide brachiopod in the investigated material. This species was found in 10 Exbodi stations with a very wide depth range (159 to 1100 m) but as noted before (see Frenulina sanguinolenta above) this may be an artefact. Already noted from New Caledonian waters (Laurin 1997;Bitner 2007aBitner , 2009Bitner , 2010, Thecidellina maxilla is widely distributed in the SW Pacifc, from New Zealand to French Polynesia (Lee and Robinson 2003;Bitner 2007bBitner , 2008Bitner , 2014Logan 2007;MacFarlan et al. 2009).

Summary
The brachiopods collected south of New Caledonia during the Terrasses cruise are represented by 15 species belonging to 13 genera. In the material from the Loyalty Ridge collected during the Exbodi cruise 19 species belonging to 16 genera have been identified. Fourteen species, i.e. Novocrania sp., Basiliola beecheri, B. lucida, Basiliolella grayi, Ebiscothyris bellonensis, Stenosarina crosnieri, S. globosa, Kanakythyris pachyrhynchos, Terebratulina pacifica, Fallax neocaledonensis, Septicollarina zezinae, Frenulina sanguinolenta, Annuloplatidia richeri and Campages mariae are common to both collections. One species, Xenobrochus africanus, found in the Terrasses collection was not recognized in the Exbodi material, whereas Neoancistrocrania norfolki, Xenobrochus indianensis, Eucalathis murrayi, Annuloplatidia curiosa, and Thecidellina maxilla were found in the Exbodi cruise but not in the Terrasses cruise. Eucalathis murrayi was reported for the first time from the New Caledonian region. Most species recognized here have a wide geographical distribution, being known either in the Western Pacific or in the Indo-West Pacific Province. Only four species, E. bellonensis, S. globosa, K. pachyrhynchos, and A. richeri can be treated as endemic to the New Caledonian region.
With the new record of E. murrayi from New Caledonia, the total number of species recognized in this region is now 45 (d 'Hondt 1987;Laurin 1997;Bitner 2007aBitner , 2009Bitner , 2010Bitner , 2011Bitner , 2014Bitner et al. 2008;Bitner and Cohen 2015), of which 8 are in common with New Zealand (compare Bitner 2010Bitner , 2014, and this study). The New Caledonian brachiopod fauna shows the greatest affinity with that from Fiji, sharing 11 of 22 species (Bitner 2006b(Bitner , 2008.