Mussinae Ortmann 1890
Creators: name: Budd, Ann F.
name: Fukami, Hironobu
name: Smith, Nathan D.
name: Knowlton, Nancy
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Cnidaria
Anthozoa
Scleractinia
Faviidae

description: SUBFAMILY MUSSINAE ORTMANN, 1890: 315   Type genus: Mussa Oken, 1815   
 Original description: ‘Von der Basis der Koralle erhebt sich keine Ringfalte, die eine echte Mauer abscheidet... Die Septen verbinden sich durch seitliche Verschmelzung zu einer falschen Mauer... Koloniebildung durch Theilung. Vorwiegend acrogenes Wachstum mit reichlicher Traversenbildung.’ (Ortmann, 1890: 314–315).   
 Diagnosis: Macromorphology: solitary or colonial; corallites discrete, or arranged in uniserial or multiserial valleys formed by circumoral budding (includes meandroid and phaceloid forms); coenosteum usually absent (except Isophyllia); medium to large calices with high relief (> 6 mm); widely spaced septa (< six per 5 mm); relatively small trabecular columella, with either lamellar or trabecular centre linkage; reduced epitheca; well-developed endotheca (Fig. 2).   
 Micromorphology: regular, tall (> 0.6 mm), widely spaced (1–2 mm), spine-shaped septal teeth, with circular bases; interarea of teeth consisting of horizontal bands; weak, aligned septal granules consisting of diffuse spikes (Figs 3, 4).   
 Microstructure: mostly parathecal corallite walls, containing trabeculothecal elements; clusters of centres of calcification within the costosepta and columella well developed, widely separated (> 0.6 mm), and connected by medial lines (Figs 5, 6).   
 Genera included:   
 Mussa Oken, 1815   
 Isophyllia Milne Edwards & Haime, 1851a Mycetophyllia Milne Edwards & Haime, 1848 Scolymia Haime, 1852   
 Remarks: As explained by Vaughan & Wells (1943: 191), ‘the most marked feature of the group is the large, multi-trabecular septal dentations marking the most complex type of faviid septum’. Both traditional Atlantic and Indo-Pacific ‘mussids’ have spine-shaped or triangular teeth. However, the teeth of traditional Indo-Pacific ‘mussids’ are orientated parallel to the septal plane, whereas the teeth of traditional Atlantic ‘mussids’ are transverse, sometimes forming carinae. Moreover, the septal granulation of traditional Indo-Pacific ‘mussids’ consists of rounded knobs, whereas the granules of traditional Atlantic ‘mussids’ consist of spikes. The walls of traditional Indo-Pacific ‘mussids’ are thickened extensively by stereome (see description in Budd & Stolarski, 2009).   
 The subfamily Mussinae is monophyletic (Fig. 7) and distinguished from the subfamily Faviinae on the basis of: greater distances (> 0.6 mm) between costoseptal clusters of calcification centres in the Mussinae, teeth with circular bases and weak granules in the Mussinae, and circumoral budding with wide septal spacing (< six septa per cm) in the Mussinae.   
 Distribution: Atlantic only.   
 GENUS MUSSA OKEN, 1815: 73 (FIGS 9A, B, 12A, B, 18A–C, 22A–C)   
 [all taxa in Oken, 1815 rejected by ICZN opinion 417 (September 1956; ICZN Commission, 1956); but Mussa Oken, 1815 conserved by ICZN opinion 2061 (March 2004; ICZN Commission, 2004)].   
 Synonyms: Lithodendron Schweigger, 1819, tab. vi [type species: Madrepora angulosa Pallas, 1766: 299– 300, as listed by Schweigger, 1820: 415–416 (see Wells, 1936: 116).]   
 Type species: Madrepora angulosa Pallas, 1766: 299– 300; by subsequent designation, Vaughan, 1918: 122. Holotype is lost (Matthai, 1928). We herein designate specimen YPM9035 (Fig. 9A, B) collected by J. C. Lang at Lime Cay off Port Royal, Jamaica as the neotype of Mussa angulosa (Pallas).   
 Original type species locality: ‘Mare Americanum’ (Pallas, 1766: 300) [Recent].   
 Early descriptions:   
1. ‘Sterne vertieft am End, meist gedrückt, weiter als Stamm, einzel oder wenige.’ (Oken, 1815: 73).  
2. ‘Large Astraeidae, segregate, also explanatoglomerate; tentacles numerous, unequal, the inner tumid. Coralla calicularly branched or explanatoglomerate; calicles very stout, subturbinate, with orbiculate or lobed cells, sometimes very broadly compressed with the cells long meandering; exterior stoutly lamello-striate and echinato-dentate; lamellae coarsely dentate or gashed-toothed, unequally exsert.’ (Dana, 1846: 173).  
3. ‘Le polpier est composé, élevé, plus ou moins cespiteux; les polypiérites sont libres entre eux ou unis en séries toujours simples et toujours libres latéralement. Les murailles sont nues ou ne présentent qu’une épithèque rudimentaire; elles sont striées longitudinalement et garnies d’épines plus ou moins nombreuses. Les calices sont plus ou moines déformés; ils ont une fossette bien distincte et même assez profonde; la columelle est spongieuse et plus or moins développée. Les systèmes cloisonnaires sont en général inégaux et irréguliers, mais on reconnaît ordinairement dans l’appareil septal des traces manifested du type hexaméral. On trouve toujours des cloisons nombreuses, débordantes, très-peu granulées et fortement dentées; leurs dents sont longues, mais inégales, les extérieures étant beaucoup plus fortes que les autres et spiniformes. Les loges interseptales sont médiocrement profondes; le tissu endothécal est bien développé.’ (Milne Edwards, 1857: 328–329).  
 Subsequent morphological descriptions (Matthai, 1928 and later): Matthai (1928: 202–208); Wells (1936: 120–121; 1956); Vaughan & Wells (1943: 192, 195; F418); Walton Smith (1971: 92); Zlatarski & Estalella (1982: 165–177); Veron (2000: vol. 3: 64–65).   
 Diagnosis: Macromorphology: colonial; intracalicular budding. Phaceloid, with short series (usually one to three centres per series, but occasionally up to five); large calices (2.5–4.5 cm) with high relief (> 6 mm), four septal cycles, slightly unequal; thin, curved septa, with wide septal spacing; continuous, spongy (> three threads) columella with trabecular linkage; reduced epitheca; no septal or paliform lobes; abundant endotheca (Figs 9A, B, 12A, B).   
 Micromorphology: high (> 0.6 mm), widely spaced (1–2 mm), spine-shaped, pointed teeth, regularly arranged; layered (banded) interarea of septal teeth; teeth in major and minor septal cycles similar in size; spongy columella, with columellar teeth differing in size and shape from septal teeth; spiky, aligned granules (Fig. 18A–C).   
 Microstructure: parathecal wall with trabeculothecal elements. Widely separated (> 1.2 mm), welldeveloped clusters of calcification centres that cross medial lines; reduced thickening deposits (Fig. 22A–C).   
 Included species [monotypic genus]: Mussa angulosa (Pallas, 1766: 299). [Holotype is from ‘Mare Americanum’ and is lost; neotype (herein designated) = YPM9035, Fig. 9A, B, Port Royal, Jamaica.]   
 Remarks: Concepts of the genus have progressively narrowed through time. In Vaughan & Wells (1943) and Wells (1956), the genus was broadly defined to include solitary forms [e.g. Scolymia (= Lithophyllia)] in addition to the phaceloid colonial form Mussa angulosa. Later Wells (1964), followed by Walton Smith (1971), separated solitary Scolymia from colonial Mussa.   
 In the classification system of Vaughan & Wells (1943) and Wells (1956), the genus Mussa is distinguished by having a phaceloid colony form, regular septal dentation, and corallite centres with trabecular linkage (Vaughan & Wells, 1943: 192, 195). Our observations show further that, like other members of the subfamily Mussinae, it has a predominantly parathecal corallite wall; centres of calcification within the costosepta and columella that form a medial line crossed by well-developed clusters of centres; spine-shaped septal teeth; and septal granules consisting of aligned spikes. In addition to colony form, this genus differs from the meandroid members of the subfamily Mussinae by having four septal cycles and a spongy columella. Atlantic Mussa is superficially similar in growth form to Indo-Pacific Lobophyllia, but differs by having trabecular linkage (not lamellar) between corallite centres, better developed septal granules, and limited thickening deposits (e.g. thin septa).   
 The genus Mussa is recognized as monotypic by Walton Smith (1971); Zlatarski & Estalella (1982); Cairns, Hoeksema & Land (1999); and Veron (2000).
description: Published as part of Budd, Ann F., Fukami, Hironobu, Smith, Nathan D. & Knowlton, Nancy, 2012, Taxonomic classification of the reef coral family Mussidae (Cnidaria: Anthozoa: Scleractinia), pp. 465-529 in Zoological Journal of the Linnean Society 166 (3) on pages 496-499, DOI: 10.1111/j.1096-3642.2012.00855.x, http://zenodo.org/record/5409083