Amphiura princeps Koehler 1907
Amphiura princeps Koehler, 1907 (Fig. 9) Type locality. Straits of Magellan, Chile. Maximum size. dd up to 12 mm (Borges & Amaral 2005). Material examined. 3 specimens (dd: 5.7– 6 mm) in subtidal. ZUEC OPH 2211, St. 71, 1 spm; ZUEC OPH 2277, St. XXVI, 1 spm; ZUEC OPH 2353, St. XXXIV, 1 spm. Desc...
Main Authors: | , , , , , |
---|---|
Format: | Text |
Language: | unknown |
Published: |
Zenodo
2018
|
Subjects: | |
Online Access: | https://dx.doi.org/10.5281/zenodo.5985126 https://zenodo.org/record/5985126 |
Summary: | Amphiura princeps Koehler, 1907 (Fig. 9) Type locality. Straits of Magellan, Chile. Maximum size. dd up to 12 mm (Borges & Amaral 2005). Material examined. 3 specimens (dd: 5.7– 6 mm) in subtidal. ZUEC OPH 2211, St. 71, 1 spm; ZUEC OPH 2277, St. XXVI, 1 spm; ZUEC OPH 2353, St. XXXIV, 1 spm. Description. Disc: (dd: 6 mm) pentagonal, covered by numerous small and imbricated scales, approximately 22 between the central primary plate and the edge of the disc. Primary radial plates evident. Radial shields acute proximally, divergent, internally straight and externally slightly curved, and separated by irregular scales (Fig. 9A). Ventral interradius covered with scales smaller than the dorsal ones and strongly imbricated, mainly those near the bursal slits. Bursal slits narrow and long (Fig. 9B). Oral shields spearhead-shaped, distal edge lobed. Madreporite larger than other oral shields and with pores. Adoral shields triangular, broadened distally and united proximally. Two lateral oral papillae, buccal scale higher up on the jaw. A pair of broadened infradental papillae (Fig. 9C). Arms: dorsal arm plates fan-shaped, twice as long as wide, convex distally and obtuse angle proximally, contiguous (Fig. 9D,F). Ventral arm plates pentagonal, as long as wide, proximal acute angle pointed and distal edge straight, contiguous (Fig. 9E,G). Two tentacle scales, the larger inserted on the ventral arm plate and the smaller on the lateral arm plate (Fig. 9E). Variable number of arm spines, at proximal segments two or three, up to six at 15th segment. At distal segments (20–24), the number of spines decreases. Ventral spines of the first arm segment may be curved hook-like with the pointed end towards the disc (Fig. 9C). Lateral arm plates (Fig. 9H, I): general outline: ventral portion projecting ventro-proximalwards; ventro-distal tip not projecting ventralwards. Outer surface ornamentation: trabecular intersections protruding to form knobs approximately the same size as stereom pores. Outer proximal edge: surface lined by discernible band of different stereom structure, restricted to central part; without spurs; central part not protruding; surface without horizontal striation. Spine articulations: on same level as remaining outer surface, middle spine articulation larger; distance between spine articulations increasing dorsalwards. Lobes simply separated, equal-sized; lobes parallel, bent, and oriented nearly horizontal; stereom massive; sigmoidal fold absent. Inner side, ridges and knobs: two separate (rarely merged) central knobs; without additional dorsal structure on inner side; single large perforation on inner side. Vertebrae: zygospondylous of universal type and keeled. Large groove on proximal side of vertebrae dorsally corresponding to distalwards projecting dorso-distal muscular fossae of distal side (Fig. 9J). Zygocondyles dorsalwards converging and zygosphene fused with pair of zygocondyles (Fig. 9K). Dorso-distal muscular fossae transformed distalwards almost projecting beyond zygocondyles (true keel) (Fig. 9L). Zygosphene not projecting beyond ventral edge of zygocondyles (Fig. 9M). Taxonomic comments. The vertebrae possess a dorsal distal keel, but the dorsal projections and depressions, connected by dorsal accessory muscles, are not as evident as in Hemipholis cordifera and Ophiothrix angulata . The number of arm spines is variable ranging five to six (Bernasconi & D'Agostino 1977). Two or three arm spines were observed in proximal segments, but up to six at 15th segment. Therefore, this feature is regarded as variable and should not be used for species identification (Borges 2006). The six primary plates are often evident, but in some specimens only the centrodorsal is visible. A. princeps is similar to A. joubini , but A. joubini is an Antarctic species characterized by a pointed to spiniform distal oral papilla, oral shields that are broadly triangular to spearhead shaped, long narrow radial shields (four times as long as wide), an absence of disc plates on the ventral surface near the oral shield, and arm spines that can be elongated into a sharp hyaline (glassy) and/or bent to bifurcated tip near the disc (Brogger & O'Hara 2015). It is important to highlight that all records of A. joubini in Brazil should be reviewed (Tommasi 1970; Manso & Absalão 1988; Manso 1989; Absalão 1990; Manso 1993; Pires-Vanin et al . 1997; Capítoli & Monteiro 2000; Capítoli & Bemvenuti 2004; Netto et al . 2005; Oliveira et al . 2010; Pires-Vanin et al . 2014), due to the similarity between A. princeps and A. joubini as suggested by Brogger & O'Hara (2015). Remarks. Its occurrence on southeastern and southern Brazilian coast is possibly due to colder water masses, e.g. South Atlantic Central Water (Tommasi 1970). It is a eurythermal species with a wide geographic and bathymetric distribution (Borges & Amaral 2005); it is dioecious with the male gonads easily distinguished in spawning season (Mortensen 1936). It lives on sand and muddy bottom (Alvarado & Solís-Marín 2013). A. princeps was collected from sand (medium sand) and rubble bottom with a dredge (2 spms) and van Veen grab (1 spm). Distribution. Temperate South America (realm), Warm Temperate Southwestern Atlantic (province): Southeastern Brazil (Borges et al . 2002; Borges & Amaral 2005) and Uruguay – Buenos Aires Shelf (Lucchi 1985); Magellanic (province): North Patagonian Gulfs to Channels and Fjords of Southern Chile (Koehler 1907; Clark 1915; Mortensen 1936; Bernasconi 1965; Bernasconi & D'Agostino 1977). From intertidal to 107 m depth (Alvarado & Solís-Marín 2013; Brogger & O'Hara 2015). The present study samples occurred at depths ranging from 20 to 21.5 m. Selected references. Koehler (1907): p. 303–305, pl. 12(28–29); Clark (1915): p. 235; Mortensen (1936): p. 285–286, fig. 22, pl.7(10); Bernasconi (1965): p. 150, pl. 1(1), 2(1); Bernasconi & D'Agostino (1977): p. 85–87, pl. 6(1,2); Lucchi (1985): p. 122, fig. 2, 25–26; Brogger & O'Hara (2015): p. 435–436 [as Amphiura princeps ]; Bernasconi & D'Agostino (1977): p. 80, pr.7, fig. 3,4; Borges et al . (2002): p. 56, fig. 33a,b; Borges & Amaral (2005): p. 264, fig. a–c; Alitto et al . (2016): p. 4, 5, fig. 3G,H [as Amphiura joubini ]. : Published as part of Alitto, Renata A. S., Bueno, Maristela L., Guilherme, Pablo D. B., Domenico, Maikon Di, Christensen, Ana Beardsley & Borges, Michela, 2018, Shallow-water brittle stars (Echinodermata: Ophiuroidea) from Araçá Bay (Southeastern Brazil), with spatial distribution considerations, pp. 1-66 in Zootaxa 4405 (1) on pages 28-31, DOI: 10.11646/zootaxa.4405.1.1, http://zenodo.org/record/3097993 : {"references": ["Koehler, R. (1907) Revision de la collection des ophiures du Museum d'Histoire Naturelle de Paris. Bulletin Scientique de la France et de la Belgique, 41, 279 - 351.", "Borges, M. & Amaral, A. C. Z. (2005) Classe Ophiuroidea. In: Amaral, A. C. Z., Rizzo, A. E. & Arruda, E. P. (Eds.), Manual de identificacao dos invertebrados marinhos da regiao sudeste-sul do Brasil. EdUSP, Sao Paulo, pp. 237 - 272.", "Bernasconi, I. & D'Agostino, M. M. (1977) Ofiuroideos del mar Epicontinental Argentino. Revista del Museo Argentino de Ciencias Naturales \" Bernardino Rivadavia \", Hidrobiologia, 5, 65 - 114.", "Borges, M. (2006) Taxonomia, distribuicao e biologia reprodutiva de Ophiuroidea (Echinodermata) das Regioes Sudeste e Sul do Brasil. Phd thesis, Universidade Estadual Paulista \" Julio de Mesquita Filho \", Rio Claro, 143 pp.", "Brogger, M. I. & O'Hara, T. D. (2015) Revision of some ophiuroid records (Echinodermata: Ophiuroidea) from Argentina. Zootaxa, 3972 (3), 432 - 440. https: // doi. org / 10.11646 / zootaxa. 3972.3.8", "Tommasi, L. R. (1970) Os ofiuroides recentes do Brasil e de regioes vizinhas. Contribuicoes Avulsas do Instituto Oceanografico, Universidade de Sao Paulo, 20, 1 - 146.", "Manso, C. L. C. & Absalao, R. S. (1988) Ophiuroidea: Situacao Pre Operacional nos sacos de Piraquara, regiao sob influencia da descarga da Central Nuclear Almirante Alvaro Alberto (CNAAA). Revista Brasileira de Biologia, 48, 75 - 82.", "Manso, C. L. C. (1989) Os Echinodermata da plataforma continental interna entre Cabo Frio e Saquarema, Rio de Janeiro, Brasil. Revista Brasileira de Biologia, 49, 355 - 359.", "Absalao, R. S. (1990) Ophiuroid assemblages off the Lagoa dos Patos outlet, southern Brazil. Ophelia, 31, 133 - 143. https: // doi. org / 10.1080 / 00785326.1990.10430857", "Manso, C. L. C. (1993) Ofiuroides da Plataforma Brasileira. Parte II: Norte do Estado do Rio de Janeiro, Estado do Espirito Santo, Sul do Estado da Bahia e Bancos Royal Charlotte, Hostpur e Davis (Echinodermata: Ophiuroidea). Revista Brasileira de Biologia, 35, 189 - 195.", "Pires-Vanin, A. M. S., Corbisier, T. N., Arasaki, E. & Moellmann, A. M. (1997) Composicao e distribuicao espaco-temporal da fauna bentica no Canal de Sao Sebastiao. Relatorios Tecnicos do Instituto Oceanografico, 41, 29 - 46.", "Capitoli, R. R. & Monteiro, A. M. G. (2000) Distribuicao e abundancia de ofiuroides na plataforma interna do extremo sul do Brasil. Atlantica, 22, 41 - 56.", "Capitoli, R. R. & Bemvenuti, C. E. (2004) Distribuicao batimetrica e variacoes de diversidade dos macroinvertebrados bentonicos da plataforma continental e talude superior no extremo sul do Brasil. Atlantica, 26, 27 - 43.", "Netto, L. F., Hadel, V. F. & Tiago, C. G. (2005) Echinodermata from Sao Sebastiao Channel (Sao Paulo, Brazil). Revista de Biologia Tropical, 53, 207 - 218.", "Oliveira, J. P., Oliveira, J. & Manso, C. L. C. (2010) Inventario da colecao de equinodermos do LABIMAR, Campus Prof \u00b0. Alberto Carvalho, Universidade Federal de Sergipe. Scientia Plena, 6, 1 - 14.", "Pires-Vanin, A. M. S., Muniz, P. & Bromberg, S. (2014) Inventory of the marine soft bottom macrofauna of Sao Sebastiao Channel, southeastern Brazilian continental shelf. Check List, 10, 795 - 807. https: // doi. org / 10.15560 / 10.4.795", "Mortensen, T. (1936) Echinoidea and Ophiuroidea. Discovery Reports, 12, 199 - 348, pls. 1 - 9.", "Alvarado, J. J. & Solis-Marin, F. A. (2013) Echinoderm research and diversity in Latin America. Springer, Berlin / Heidelberg, 665 pp. https: // doi. org / 10.1007 / 978 - 3 - 642 - 20051 - 9", "Borges, M., Monteiro, A. M. G. & Amaral, A. C. Z. (2002) Taxonomy of Ophiuroidea (Echinodermata) from the continental shelf and slope of the southern and southeastern Brazilian coast. Biota Neotropica, 2, 1 - 69. https: // doi. org / 10.1590 / S 1676 - 06032002000200010", "Lucchi, C. (1985) Ophiuroidea (Echinodermata) del frente maritimo uruguayo hasta 800 m de profundidad, con claves para su identificacion. Contribuciones del Departamanto de Oceanografia (F. H. C.) Montevideo, 2, 115 - 171.", "Clark, H. L. (1915) Catalogue of Recent Ophiurans: Based on the Collection of the Museum of Comparative Zoology. Memoirs of the Museum of Comparative Zoology, 25, 165 - 376.", "Bernasconi, I. (1965) Ophiuroidea de Puerto Deseado (Santa Cruz, Argentina). Physis, Seccion A (Buenos Aires), 25, 143 - 152.", "Alitto, R. A. S., Bueno, M. L., Di Domenico, M. & Borges, M. (2016) Annotated checklist of Echinoderms from Araca Bay, Southeastern Brazil. Check List, 12, 1 - 15. https: // doi. org / 10.15560 / 12.1.1836"]} |
---|