Dotted blue eye
| Dotted blue eye | ||||||||||||
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Variant from the Aru Islands (male) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Pseudomugil gertrudae | ||||||||||||
| Weber , 1911 |
The spotted blue-eye ( Pseudomugil gertrudae ), also spotted or Gertrud's blue-eye , is a small freshwater fish from the family of blue-eyes (Pseudomugilidae). It was first collected on one of the Aru Islands (Trangan), described on the basis of these specimens by Weber in 1911 and named gertrudae after the wife of the German zoologist Merton , who visited the Aru Islands between October 1907 and August 1908.
Features and systematics
The dotted blue-eye has an elongated body about 30 mm long, which is colored semitransparent, silvery-blue or golden-yellow, depending on where it was found. Some rows of scales are partly lined with black, giving the impression of a grid pattern. The eyes are colored blue. It has two closely spaced dorsal fins, the first smaller than the second. The tips of the pectoral fins can be colored yellow, orange or orange-red depending on where they are found. The other fins can be transparent, whitish, silver-gray or yellow in color and the males have many small, dark, round spots. The males have long dorsal, ventral and anal fins.
The local populations of the spotted blue-eye differ significantly in color and body size, as well as in fin size and shape. The genetic differences ( mitochondrial DNA ) between Australian and New Guinea populations are of the same order of magnitude as is typical for different species. It is closely related to the New Guinea endemic species Pseudomugil paskai and Pseudomugil luminatus .
Fins formula : dorsal IV – VI / 6–8, anal I / 9–12, pectoral 8–11
distribution
The dotted blue-eye occurs in places around the Arafura Sea . There are Australian populations in waters that drain into the Timor Sea and the Gulf of Carpentaria, from the islands of Bathurst, Melville and Groote Eylandt, on the Cape York Peninsula and some islands of the Torres Strait. The known occurrences in New Guinea are on the Aru Islands, as well as in the Pahoturi, Fly and Bensbach river systems.
The species occurs in small (rainforest) streams, oxbow lakes of larger rivers, swamps and billabongs , often with dense underwater vegetation and a muddy bottom that is covered with dead branches and leaves. Floating plants or leaves often float on the surface of the water. In some habitats the water is acidic and has a strong tea color due to decomposing vegetation. The fish prefer to stay in the calm water areas or near the shore. Populations of the spotted blue-eye were found in bodies of water with very different water values, e.g. B. at temperatures between 12 and 34 ° C, pH values between 3.7 and 9.4 and conductivities between 12 and 646 µS / cm.
literature
- Weber, M. (1911). The fish of the Aru and Kei Islands. A contribution to the zoogeography of these islands . Treatises of the Senckenberg Natural Research Society Frankfurt-a.-M. 34: 1-49, Pls. 1-2.
- Heiko Bleher : The Aru Islands - history and new discoveries . Amazonas No. 19, September / October 2008, 4 (5): 20-30.
- Günther Sterba : The world's freshwater fish. 2nd Edition. Urania, Leipzig / Jena / Berlin 1990, ISBN 3-332-00109-4 .
Web links
- Adrian R. Tappin: Pseudomugil gertrudae (English)
- Dotted blue eye on Fishbase.org (English)
Individual evidence
- ↑ GR Allen, PJ Unmack, RK Hadiaty: Pseudomugil luminatus, A New Species of Blue-eye (Teleostei: Pseudomugilidae) From Southern New Guinea, With Notes on P. gertrudae . In: Fishes of Sahul . tape 30 , no. 1 , 2016, p. 950-961 .