Pholidichthys
| Pholidichthys | ||||||||||||
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White-stripe eel goby ( Pholidichthys leucotaenia ) |
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| Systematics | ||||||||||||
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| Scientific name of the family | ||||||||||||
| Pholidichthyidae | ||||||||||||
| de Beaufort , 1951 | ||||||||||||
| Scientific name of the genus | ||||||||||||
| Pholidichthys | ||||||||||||
| Bleeker , 1856 |
Pholidichthys is a species of marine fish that is poor in species and occurs in the tropical, western Pacific. Pholidichthys is placed in the monogeneric family Pholidichthyidae and includes two species:
- the white-stripe eel goby ( Pholidichthys leucotaenia ) lives in coral reefs from the Philippines to the Solomon Islands ,
- Pholidichthys anguis on mud floor on the coast of Northern Australia.
features
The white-stripe eel goby grows to about 45 cm long, the only known adult specimen of Pholidichthys anguis was a 24.5 cm long female. The body is scaleless and elongated like an eel. The wide mouth extends to a point below the rear edge of the eye. The jaw teeth are conical and pointed. Palatine teeth are missing. The fish have only one nostril on each side of their head. The gill openings are large and touch at the bottom in front of the gill cover . All fin rays are segmented, spines are absent. The dorsal fin, which begins just behind the gill cover, and the anal fin are long and have grown together with the caudal fin to form a continuous fin edge.
Both species show a clear dimorphism between juvenile and adult fish. Young Pholidichthys anguis are light, the belly white and show a dark pinstripe on the body sides. Young fish of P. leucotaenia are black, with a conspicuous bluish-white vertical stripe on the flanks and a white belly. Adults are blackish with sooty spots ( P. anguis ) or irregular yellow bands ( P. leucotaenia ). The lateral line cannot be seen or is barely visible, consists of tiny pit organs and begins high in the front of the body to drop behind the pectoral fins to the lateral center line.
Habitat and way of life
Adult Pholidichthys live very hidden, either in caves and crevices in coral reefs or in tunnels in the muddy seabed. They are likely to be largely nocturnal. The fry live in schools.
Systematics
The systematic position of the genus was controversial for a long time, as the animals have characteristics of both gobies and slime fish. The uncertainty in the systematic assignment is also clear with the English name, where the genre is referred to as either Engineer gobys or Convict Blennys . In the past Pholidichthys was also assigned to the worm gobies (Microdesmidae), compared with Notograptus or placed in the relationship of the wrasse (Labridae).
Springer and Freinhofer (1976) presented very detailed studies on skeletal and nervous system, to clarify the relationship - but it only came out that little for the mucous Fishy speaks (Blennioidei). A study by the molecular biologists Matt Craig and Leo Smith also revealed a relationship with the blimp-like and jawfish (Opistognathidae). No relationship with the goby-like (Gobioidei) could be proven. They are therefore not related to the goby subfamily Amblyopinae and the goby genus Gobioides , which have a very similar eel-like shape to Pholidichthys . The scientific name indicates similarity (but not relationship) with Pholis from the butterfish family .
The American ichthyologist Joseph S. Nelson , author of the standard work on fish systematics Fishes of the World , placed them in the fourth edition of the work in their own subordination Pholidichthyoidei in the order of the " perch-like (Perciformes)" after they were still in the third edition Dragon fish (Trachinoidei) were counted.
In July 2012, a group of scientists published a study on the monophyly of wrasse-like (including wrasses and cichlids), which they reject, and came to the conclusion that cichlids (Cichlidae), inhabitants of tropical freshwater, are the sister group of the Pholidichthyidae. Common features that Pholidichthys shares with the cichlids are the single nostril on each side of the head, most other fish have two on each side of the head, the paired adhesive organ on the top of the head of the larvae, which allows them to attach themselves to objects as long as they are not yet able to swim , and intensive brood care, which not only includes the clutch, but also larvae and fry. The latter is almost unique for marine fish and, apart from Pholidichthys, only occurs in the not very closely related swallowtail damselfish ( Acanthochromis polyacanthus ) and the three species of the damselfish genus Altrichthys .
Together with the cichlids and other taxa, Pholidichthys forms the ovalentaria , a morphologically very diverse large taxon comprising more than 4800 species, which has eggs that sink to the ground as a common diagnostic feature and that are attached with sticky filaments.
literature
- Kent E. Carpenter & Volker H. Niem: The Living Marine Resources of the Western Central Pacific. Volume 4 Bony fishes part 2 (Mugilidae to Carangidae). FAO , 1999, ISSN 1020-6868
- Joseph S. Nelson : Fishes of the World. Wiley, New York 2006, ISBN 0-471-25031-7
- Victor G. Springer & Helen K. Larson: Pholidichthys anguis, a new species of pholidichthyid fish from Northern Territory and Western Australia . Proceedings of the Biological Society of Washington
Individual evidence
- ↑ P. Wirtz: Goby or Schleimfisch. In: DATZ . Vol. 41, No. 9
- ^ VG Springer and WC Freihofer (1976): Study of the monotypic fish family Pholidichthyidae (Perciformes) .- Smithson. Contrib. Zool. 216: 1-43.
- ^ A b W. Freshness, L. Gesset: Mysterious eel gobies. In: DATZ. Vol. 59, No. 1
- ^ Joseph S. Nelson: Fishes of the World. Wiley, New York 2006, ISBN 0-471-25031-7
- ^ A b Peter C. Wainwright et al .: The Evolution of Pharyngognathy: A Phylogenetic and Functional Appraisal of the Pharyngeal Jaw Key Innovation in Labroid fishes and Beyond. Syst Biol (2012) doi : 10.1093 / sysbio / sys060
- ↑ Ellen Thaler : Eel gobies and their reproduction in the aquarium. In: Coral. No. 39, 2006
- ↑ Ricardo Betancur-R., Richard E. Broughton, Edward O. Wiley, Kent Carpenter, J. Andrés López, Chenhong Li, Nancy I. Holcroft, Dahiana Arcila, Millicent Sanciangco, James C Cureton II, Feifei Zhang, Thaddaeus Buser, Matthew A. Campbell, Jesus A Ballesteros, Adela Roa-Varon, Stuart Willis, W. Calvin Borden, Thaine Rowley, Paulette C. Reneau, Daniel J. Hough, Guoqing Lu, Terry Grande, Gloria Arratia, Guillermo Ortí: The Tree of Life and a New Classification of Bony Fishes. PLOS Currents Tree of Life. 2013 Apr 18 [last modified: 2013 Apr 23]. Edition 1. doi: 10.1371 / currents.tol.53ba26640df0ccaee75bb165c8c26288 , PDF ( Memento of the original from October 13, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Thomas J. Neara, Alex Dornburg, Ron I. Eytan, Benjamin P. Keck, W. Leo Smith, Kristen L. Kuhn, Jon A. Moore, Samantha A. Price, Frank T. Burbrink, Matt Friedman & Peter C. Wainwright: Phylogeny and tempo of diversification in the superradiation of spiny-rayed fishes. PNAS, July, 2013, doi: 10.1073 / pnas.1304661110 , PDF
Web links
- Pholidichthys on Fishbase.org (English)
- Family Pholidichthyidae - Convict blenny on Fishbase.org (English)