Enigmaster scalaris McKnight & H.E.S. Clark 1996
Enigmaster scalaris McKnight & H.E.S. Clark, 1996 H.E.S. Clark & McKnight, 1996; 207; 2001: 45 Comments. It seems possible that characters listed by McKnight and Clark (1996) may be misinterpreted from dried tissue. The fibrous rungs or bars figured in descriptions of Enigmaster appear to be...
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| Format: | Other/Unknown Material |
| Language: | unknown |
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2011
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| Online Access: | https://zenodo.org/record/6184343 https://doi.org/10.5281/zenodo.6184343 |
| Summary: | Enigmaster scalaris McKnight & H.E.S. Clark, 1996 H.E.S. Clark & McKnight, 1996; 207; 2001: 45 Comments. It seems possible that characters listed by McKnight and Clark (1996) may be misinterpreted from dried tissue. The fibrous rungs or bars figured in descriptions of Enigmaster appear to be dried connective ligaments connecting the abactinal surface facets of paired ambulacral ossicles as observed in Ceramaster and other goniasterids. Similarly, the absence of suckers on the tube feet may be a misinterpretation of tube foot from dried tissue deformation. Furthermore, the perception of a suckerless tube foot could be a dried “simple disk” type tube foot as indicated by Santos et al. (2005) who described three different types of tube feet, only one of which actually possessed a well-developed sucker. The distinctive hastate arm shape observed in Enigmaster could represent unusual phenotypic variation, which is observed in other valvatidans, such as the South African goniasterids Toraster tuberculatus and Calliaster acanthodes (Mortensen 1933) in conjunction with predation or developmental abnormalities. If the unusual characters that have been used to distinguish Engimaster are de-emphasized, the specimen described by McKnight and Clark (1996) more closely resembles Ceramaster, Peltaster or possibly Sphaeriodiscus. However, the description does not surrender a clear picture of precisely which genus Engimaster may be a synonym of and it is for this reason that Enigmaster is left in the key. Additional specimens, especially wet-preserved material, of the Engimaster morphotype may disprove or further support statements presented herein. Distribution. Adjacent to Auckland Islands, south of New Zealand, 520 m. Material examined. None. This species is known from a unique holotype housed in the Auckland Museum (AK 797001), which was unavailable for loan. No other specimens are known. Description. Because extensive descriptions of this species are outlined in McKnight and H.E.S. Clark (1996) and H.E.S. Clark and ... |
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