Muriceopsis metaclados, Castro & Medeiros & Loiola, 2010

Castro, C. B., Medeiros, M. S. & Loiola, L. L., 2010, Octocorallia (Cnidaria: Anthozoa) from Brazilian reefs, Journal of Natural History 44 (13 - 14), pp. 763-827 : 786-790

Muriceopsis metaclados sp. nov.

( Figures 1 , 7C,C′ , 11)

Muriceopsis sp. : Medeiros and Castro 1999: 11.

Muriceopsis sp. : Sánchez 2001, as Muriceopsis sp. 2 , USNM 55799, Brazil, on p. 176, as Muriceopsis sp. 2 (Brazil-55799) in table 1, Muriceopsis sp. 2 Brazil in fig. 12; non- Sanchez 2001, fig. 8A, referred to as Muriceopsis sp. 1 , USNM 55799 ( Brazil) (illustration of a mistaken specimen confirmed by S. D. Cairns, 5 January 2006).

Diagnosis

Colonies sparsely ramified, planar or bushy, never feather-shaped. Terminal branches 1.9–3.5 mm thick. Coenenchymal and outer layer of calyces with slender spindles (up to 1.39 mm long) or somewhat club-shaped sclerites (up to 0.6 mm long), which may have foliate or spiny tubercles on their outer surface.

Description

Variable species. Colonies sparsely ramified, planar or bushy ( Figure 7C ). Branches rounded in transverse section ( Figure 7C′ ). Colonies up to 100 mm high, 40–110 mm wide, and up to 100 mm deep; trunk diameter near the basis 1.8–5.0 mm. Horny axis rounded in transverse section, brownish. Main branches or primary branches up to 140 mm long (straightened), diameter with calyces 1.8–5.7 mm, without calyces 1.0–4.0 mm; diameter at their proximal end 1.9–5.0 mm. Secondary branches 8– 118 mm long; diameter with calyces 1.1–5 mm, without calyces 1–4.1 mm; diameter at their proximal end 1.5–4.2 mm. Terminal twigs 5–60 mm long, diameter with calyces 1.9–3.5 mm, without calyces 1.3–2.4 mm; diameter at their proximal end 2.1– 3.3 mm. Distance between consecutive branches 5–190 mm. Calyces all around branches (although they may be lacking on parts of branches), half-cup-shaped, 0.6– 2.7 mm high, 0.4–1.7 mm wide ( Figure 7C′ ). Distance between adjacent calyces from contiguous to 3.4 mm apart; 10–41 calyces/centimetre. Coenenchyme with spindles of uniform sculpture of small tubercles (0.12–1.22 mm long) or inner face of small tubercles and outer face of large spines (0.15–1.39 mm long); sometimes these spines may cluster near an end of the spindle, giving it a club-like appearance. (0.15– 0.6 mm long) ( Figure 11A ). Calyces with sclerites similar to those of the coenenchyme: uniform spindles (0.12–1.17 mm long); unilaterally spinose spindles (0.13– 1.07 mm long), or club-like (0.13–0.73 mm long) ( Figure 11B ). Axial sheath mainly with spindles of uniform sculpture of small tubercles, 0.15–0.60 mm long ( Figure 11C ). Polyps with poorly ornamented rods (0.02–0.42 mm long) ( Figure 11D ). Colony colour: uniform white or cream. Sclerites white or colourless (transparent); axial spindles purple.

Material

Holotype. Brazil: Ceará: off Iguapé Point and Maceió Point ( NOAS #1693 , 03°30′ S, 037°56.5′ W, 49 m, August–December 1967 one colony plus five fragments) ( MNRJ 03281 ) ( Figure 1 ).

Paratypes. Brazil: Ceará – off Acaraú (identified by F.M. Bayer as Muriceopsis sp. ) ( USNM 55799 , 44 m) ; Bahia, off Todos os Santos Bay (13°04′30′′ S, 038°23′30′′ W) ( MNRJ 04131 , 04147 , 05082 , 05086 , 91 m) , off Boipeba Island (13°36.67′ S, 038°47.212′ W) ( MNRJ 05082 , 40–45.2 m) , California Reef (18°07′ S, 038°34′ W) ( MNRJ 04147 , 20–30 m) , Hotspur Seamount (18°01′22′′ S, 035°53′28′′ W) ( MNRJ 04131 , 60 m) ; Espírito Santo, Vitória Seamount (off Vitória – 20°34.37′ S, 038°03.53′ W ( MNRJ 04869 , 55 m) ; Rio de Janeiro, off São João da Barra (21°30′ S, 040°18′ W) ( MNRJ 04127 , 04128 , 04872 , 52 m) ( Figure 1 ).

Other specimens. Brazil: Maranhão ( NOAS #1750 , 00°04′ S, 044°33.5′ W, two fragments, UFPE-DO; NOAS #1875 , 00°56′ S, 043°41.5′ W, two fragments, UFPE- DO; NOAS N-NEII #1872 , 01°20′ S, 043°33.5′ W, two fragments, UFPE-DO) ; Ceará ( NOAS #1711 , 02°25′ S, 039°30.5′ W, two fragments, UFPE-DO; CN #66 , 02°41′ S, 039°10′ W, two fragments, UFPE-DO; CN #61 , 02°59′ S, 038°58′ W, more than 10 fragments, UFPE-DO; CN #15 , 01°30′ S, 038°48′ W, one colony plus three fragments, UFPE-DO; CN #23 and #26, 02°15′ S, 038°15′ W; CN #73 , 03°18′ S, 038°14′ W, three lots, more than 70 fragments, UFPE-DO; NOAS #1693 , 03°30′ S, 037°56.5′ W, one colony plus five fragments, UFPE-DO; CN #52 , 03°40′ S, 037°54′ W, more than 10 fragments, UFPE-DO; CN #19 , 01°56′ S, 037°51′ W, more than 50 fragments; NOAS #1701 A, 01°57′ S, 037°46′ W, more than 10 fragments, UFPE-DO) ; Rio Grande do Norte ( NOAS #1684 , 03°59.5′ S, 035°53.7′ W, three fragments; NOAS #1684 A, 03°59.5′ S, 035°53.7′ W, six fragments, UFPE-DO; NOAS #1684 B, 03°59.5′ S, 035°53.7′ W, four fragments, UFPE-DO) ; Paraíba ( NOAS N-NEII #1858 , 06°50′ S, 034°44′ W, three fragments, UFPE-DO) ( Figure 1 ) .

Comparative material

Muriceopsis sulphurea ( Donovan, 1825) – see list of studied material under the species heading.

Muriceopsis flavida (Lamarck, 1815) – Saint John, Virgin Islands, USA (MNRJ 01262).

Muriceopsis petila Bayer, 1961 , (paratype) – Tongue of the Ocean, Bahamas ( USNM 50384 ).

Type depository

Museu Nacional, Rio de Janeiro ( MNRJ 03281).

Etymology of the specific name

Greek meta (variable) + Greek clados (branch).

Remarks

Aurivillius (1931) lists five other species assigned to Muriceopsis . Four of them were included in the synonymy of Muriceopsis sulphurea by Bayer (1961): Muriceopsis bicolor , Muriceopsis acropora , Muriceopsis humilis and Muriceopsis tuberculata . The remaining species is Muriceopsis chuni ( Kükenthal, 1919) . However, the illustration of a colony included in Kükenthal (1919) does not show the typical calyces of Muriceopsis (with a lower lip); instead it shows symmetrical coenenchymal mounds. Also, although Kükenthal (1919) created this species as Muriceides chuni , sclerites figured in his plates are not similar to those diagnostic of Muriceides : they do not show spindles with projecting spines. This species differs also from M. metaclados in the exclusive occurrence of white axial sheath sclerites (according to Aurivillius 1931). Deichmann and Bayer (1959) included several species and varieties of Muricea humilis Milne-Edwards and Haime, 1857 , Muricea acropora Verrill, 1912 and Muricea bicolor Wright and Studer, 1889 in the synonymy of Muriceopsis sulphurea .

Bayer (1961) lists three species of Muriceopsis for the western Atlantic: M. sulphurea , M. flavida and M. petila . According to comparative material and the literature (see synonym list under M. sulphurea ), M. sulphurea has much stouter sclerites on the coenenchyme and calyx. Also, this species has rare purple spindles in the axial sheath ( Bayer 1961), while these sclerites are much more common than white sclerites in M. metaclados . Muriceopsis flavida has “feather-shaped colonies, often with secondary branches developing into new feathers” ( Deichmann and Bayer 1959). Moreover, their coenenchymal and calyx spindles are much smaller [spindles up to 0.33 mm and clubs up to 0.25 mm ( Bayer 1961 and comparative material)] than in the new species (spindles up to 1.39 mm and clubs up to 0.60 mm). Muriceopsis petila has coenenchymal and calyx sclerites thinner and with more delicate outer spines than the new species. Also, according to the comparative material and Bayer (1961), its branching is more regularly pinnate ( Bayer 1961: pl. IV, fig. 2) and its branches are more slen- der (“uniform diameter 1.5–2 mm ”) than in the new species.

Sánchez (2001) reviewed species of Muriceopsis and listed at least four previous valid species from the Atlantic ( M. petila , M. sulphurea , M. flavida and M. tuberculata , the latter from the African coast) and described a new species: M. bayeri . Muriceopsis bayeri could be readily distinguished from M. metaclados by the ornamentation of spindles of the external layer of the coenenchyme: “big and hypermorphic warts towards spiny and non-spiny surfaces of the sclerite” ( Sánchez 2001: 170, figs 6A, 7A; see also remarks on M. sulphurea ). A single specimen from Brazil was set apart from all other branches of his consensus tree ( Sánchez 2001: fig. 12): “ Muriceopsis sp. 2 Brazil ” ( USNM 55799). This specimen was herein examined and included as a paratype of M. metaclados sp. nov.

Species previously synonymized with M. sulphurea were described from specimens readily distinguishable from M. metaclados . The illustrations in Verrill (1912) of Muricea humilis ( Verrill 1912: pl. XXIX, fig. 1,1a; pl. XXXII, figs. 4,5; XXXV, fig. 2) and Muricea acropora ( Verrill 1912: pl. XXXII, fig. 3; pl. XXXV, fig. 1,1a) show shrub-like colonies, relatively thick branches, and stout sclerites with large spines or foliate processes, unlike those described for M. metaclados . Muricea bicolor Wright and Studer, 1889 , present “larger branches that arise at obtuse angles, but soon bend upwards and run parallel to the main stem” ( Wright and Studer 1889: 134). Also, according to Wright and Studer’s description (1889: 135), maximum length of coenenchymal sclerites is less than half the length of M. metaclados .

Specimens from the new species resemble one of the two original illustrations of Muriceopsis sulphurea (see remarks in M. sukphurea ). As the name M. sulphurea has been associated with a common shrub-like reef gorgonian since Deichmann and Bayer’s (1959) review of Muriceopsis , we hereby describe our specimens [second form in Donovan (1825), Muriceopsis sp. in Medeiros and Castro (1999) and Muriceopsis sp. 2 Brazil in Sánchez (2001)] as a new species.

Figures

Figure 1. Map of distribution of reef octocorals in different regions off the Brazilian coastline. The Espírito Santo State area (*) includes the Vitória- Trindade seamount chain. “BA Sector” refer to a division of reef areas in Bahia State by Leão (1996).

Figure 7. Muricea flamma Marques and Castro, 1995 (MNRJ 04145): (A) colony, (A′) branches. Muriceopsis sulphurea (Donovan, 1825) (MNRJ 00640): (B) colony, (B′) branches. Muriceopsis metaclados sp. nov. (MNRJ 03281 – holotype): (C) colony, (C′) branches. Scale bars: A–C, 2 cm; A′–C′, 5 mm.

Figure 11. Sclerites of Muriceopsis metaclados sp. nov. (MNRJ 03281): (A) coenenchyme; (B) calyx; (C) axial sheath; (D) polyp.