Ophiomusa lymani (W. C. Thomson 1873)
- Dataset
- Biogeography and taxonomy of Ophiuroidea (Echinodermata) from the Îles Saint- Paul and Amsterdam in the southern Indian Ocean
- Rank
- SPECIES
Classification
- kingdom
- Animalia
- phylum
- Echinodermata
- class
- Ophiuroidea
- order
- Ophiurida
- family
- Ophiomusaidae
- genus
- Ophiomusa
- species
- Ophiomusa lymani
description
Fig. 5 A – G
discussion
Remarks. Unlike many other widespread bathyal complexes, Ophiomusa lymani has always been identified as a single species that has been reported from all oceans (450 – 4800 m) except the Arctic and subantarctic / Antarctic. It has been previously reported from across the southern Indian Ocean from South Africa (Olbers et al. 2019), around Madagascar (Guille & Vadon 1986), Reunion (Vadon & Guille 1984), the SPA (Hertz 1927 b) and Southern Australia (Rowe & Gates 1995). The specimens from CP 124 are large, 23 and 25 mm dd (Fig. 5 A – D), and display all the classic characters of O. lymani, including the numerous tiny arm spines (Fig. 5 C), more than three ventral disc scales, and granulated radial shields and marginal disc scales. The specimens from stn DC 137 are small, 4 mm dd (Fig. 5 E – G). They are identified as juvenile O. lymani on the basis of having tumid primary disc plates (see Schoener 1967), granulated disc plates including radial shields which are mostly contiguous, only three arm spines, middle one becoming hooked distally, and oval tentacle scales, associated with VAPs. At this size they are reminiscent of the O. scalare Lyman, 1878 b group of species with a ventral disc surface that is dominated by a large pentagonal scale next to the oral shields which separates two tumid scales along the margin. However, O. scalare generally has smaller circular tentacle scales, disc scales may be partially covered in skin but not granulated, and the three arm spines are closely clustered together. Ophiomusa ultima Hertz, 1927 b from east Africa (238 – 977 m) and O. africanum Koehler, 1909 from Cabo Verde (219 m) have a narrower oral shield and an upper arm spine (or two) that is separated from the others. On O. ultima the 2 nd set of tentacle pores become isolated from the VAP with size, perforating the LAP, until they gradually close over and the VAP reduces in size. Ophiomusa africanum is only known from the 7 mm dd holotype, which has the second set of tentacle pores emerging through the lateral arm plate and no associated VAP.
distribution
Distribution. Arctic (95 – 2448 m), NW Atlantic (595 – 3506 m), NE Atlantic (1011 – 4829 m), NW Pacific (110 – 2310 m), NE Pacific (62 – 2904 m), W Atlantic (101 – 1965 m), E Atlantic (415 – 4088 m), W Indian (457 – 2312 m), E Indo-W Pacific (300 – 3343 m), E Pacific (730 – 2599 m), S America (700 – 3394 m), S Africa (1340 – 2780 m), S Australia (848 – 3050 m), New Zealand (495 – 3029 m). SPA (1340 – 2000 m).
materials_examined
Material examined. MD 50 CP 124, MNHN IE. 2009.1617 (2). MD 50 DC 137, MNHN IE. 2009.1616 (2).
Name
- Synonyms
- Ophiomusium lymani Thomson 1873
- Homonyms
- Ophiomusa lymani (W. C. Thomson 1873)