Stegastes nigricans és una espècie de peix de la família dels pomacèntrids i de l'ordre dels perciformes.
Els mascles poden assolir els 14 cm de longitud total.[2]
Es troba des del Mar Roig i l'Àfrica Oriental fins a les Illes de la Línia, les Illes Marqueses, les Tuamotu, les Illes Ryukyu, Nova Caledònia. Absent de les Hawaii.[2]
Stegastes nigricans és una espècie de peix de la família dels pomacèntrids i de l'ordre dels perciformes.
Stegastes nigricans, the dusky farmerfish, is a species of damselfish found around coral reefs at a depth of one to 12 meters, in tropical climates between 30°S and 30°N. They are known for farming monocultures of algae such as cyanophores and rhodophytes.
Stegastes nigricans was first described and named by Gerald Robert “Gerry” Allen and Alan R. Emery in 1985. The genus Stegastes is derived from the Greek “stegastos,” which means on or covered. Nigricans is Greek for swarthy and black-skinned.[1] Recent research has placed S. nigricans in the monotypic taxon Pomacentrinae, which is closely related to the other subfamilies Amphiprioninae and Chrominae.[2] Amphiprioninae are clown fish, which are differentiated from other organisms in their family by their bright orange and white coloration across the body and over fins and relationship with anemone. There is high variation in morph patter of Amphiprioninae, especially around their face.[3] Chrominae are closer on the phylogenetic tree to Pomacentridae than Amphiprioninae, but are able to be differentiated from Pomacentridae because Chrominae are very brightly colored with blues and purples while Pomacentridae are confined to mainly brown with some blues. These three families are all coral reef fishes, and there is usually a lot of variation and overlap from subfamily to subfamily.[4] Damselfish have been documented in the fossil record for at least 50 million years.[5]
It has an average length of 9.0 cm, but can reach lengths of 14.0 cm. It has 12 dorsal spines, and 15 to 17 dorsal soft rays. It also has 2 anal spines and 12 to 14 anal soft rays. Adults are generally brown, with the dorsal parts of the head and nape being darker, grading to tan on the lower parts of the head and breast. The scales have darker brown margins. The lips are whitish, the suborbital is mostly blue, and the preopercle and opercle scales have blue centers. The median and pelvic fins are brown, the pectorals are dusky, and sometimes there's a well-defined dark brown or blackish spot at the base of the posteriormost dorsal rays, which distinguishes it from the S. lividus, where the spot is diffuse. When males are in courtship or guarding their eggs they have a broad white bar across the middle of the body and a pale blue stripe from the mouth to the upper part of the pectoral fin.[6]
S. nigricans are found naturally in and around coral reefs. Adult S. nigricans inhabit reef flats and lagoon reefs in colonies in areas with staghorn coral. S. nigricans are limited by water temperature and their diet and have been experiencing a negative impact of their population amounts. Climate and ocean composition has been changing due to global warming and fossil fuel use, therefore this habitat is being altered and coral reefs are becoming greatly reduced.[7]
S. nigricans is most frequently found across the coast of East Africa and around Madagascar; in the British Indian Ocean Territory and the southern coasts of India; across Southeast Asia, the northern coast of Australia; and Melanesia, Micronesia and Polynesia. They can also be found less frequently in the Red Sea, the Persian Gulf, the Gulf of California, and across the Western coast of Central America.[6]
Adults inhabit reef flats and lagoon reefs. They frequently occur in colonies associated with live or dead branching staghorn coral (Acropora). They feed on algae, gastropods, sponges and copepods. They are territorial, and they maintain and "weed" filamentous algae patches growing on dead coral. They attack human intruders without hesitation, sometimes taking painful nips.
S. nigricans are oviparous and follow a distinct breeding pair relationship between males and females. Their eggs are demeral and adhere to the substrate. Males guard and tend to the egg nest via aeration and will be visited by several females throughout their time there.[7] They're particularly aggressive during reproductive periods. During aggressive encounters, they emit clicking noises. Males guard and tend the nest, visited by several females.[6]
S. nigricans practices a form of agriculture with a species of red algae. The fish will claim a patch of "brown carpet algae" (Womersleyella setacea) which it defends by chasing away other fish and sea urchins. The fish also pulls up other bits of algae that attempt to grow in the patch and swims outside of its territory to spit the invading algae out. S. nigricans do not have cellulases in their stomach, therefore they dispose of algae that they cannot digest. They must limit their diet to cyanophores and rhodophytes, which are delicate species. There are nine algae species that S. nigricans will farm for, and the algae they remove is competitively superior late-colonizing algae as opposed to the algae they can eat.[8] They also remove algae that is competitive and faster growing than their preferred delicate algae.[9] When the fish claiming a patch is removed, the patch is eaten up within a few days. When a patch of the brown carpet algae is caged to keep both S. nigricans and other fish out of the patch, other species of algae quickly overwhelm the patch. This seems to indicate the brown carpet algae are dependent on S. nigricans for its survival. The presence of S. nigricans in ecosystems greatly increases the primary productivity of the area by boosting oxygen, nitrogen, and phosphorus concentrations.[10]
Stegastes nigricans, the dusky farmerfish, is a species of damselfish found around coral reefs at a depth of one to 12 meters, in tropical climates between 30°S and 30°N. They are known for farming monocultures of algae such as cyanophores and rhodophytes.
Stegastes nigricans es una especie de peces de la familia Pomacentridae en el orden de los Perciformes.
Los machos pueden llegar alcanzar los 14 cm de longitud total.[1]
Se encuentra desde el Mar Rojo y el África Oriental hasta las Islas de la Línea, las Islas Marquesas, las Tuamotu, las Islas Ryukyu, Nueva Caledonia. Ausente de las Hawaii.
Stegastes nigricans es una especie de peces de la familia Pomacentridae en el orden de los Perciformes.
Stegastes nigricans Stegastes generoko animalia da. Arrainen barruko Pomacentridae familian sailkatzen da.
Espezie hau Agulhasko itsaslasterran aurki daiteke.
Stegastes nigricans Stegastes generoko animalia da. Arrainen barruko Pomacentridae familian sailkatzen da.
Stegastes nigricans is een straalvinnige vissensoort uit de familie van rifbaarzen of koraaljuffertjes (Pomacentridae).[1] De wetenschappelijke naam van de soort is voor het eerst geldig gepubliceerd in 1802 door Lacepède.
Bronnen, noten en/of referenties
Multimedia w Wikimedia Commons Stegastes nigricans – gatunek ryby z rodziny garbikowatych (Pomacentridae). Występuje wzdłuż raf koralowych na głębokości od 1 do 12 metrów.
S. nigricans praktykuje formę podwodnego ogrodnictwa. Żywi się krasnorostami Polysiphonia, które uprawia, poprzez np. regularne wyrywanie ze swego ogródka tego, co uważa za chwasty. Dzięki temu glony te mogą swobodnie rosnąć, zapewniając rybie przetrwanie, gdyż garbiki nie posiadają narządów zdolnych do rozgniatania celulozowych włókien, ani też enzymów potrzebnych do rozłożenia wielu gatunków glonów. Polisyfonia przegrywają konkurencję z niejadalnymi dla ryb algami, dlatego Stegastes nigricans muszą wspomagać ich wzrost właśnie poprzez tzw. ogródki i ich pielenie. Jest to związek o charakterze mutualizmu – obie strony czerpią korzyści o takim stopniu, który praktycznie wzajemnie uzależnia istnienie obu populacji[1][2].
Stegastes nigricans – gatunek ryby z rodziny garbikowatych (Pomacentridae). Występuje wzdłuż raf koralowych na głębokości od 1 do 12 metrów.
S. nigricans praktykuje formę podwodnego ogrodnictwa. Żywi się krasnorostami Polysiphonia, które uprawia, poprzez np. regularne wyrywanie ze swego ogródka tego, co uważa za chwasty. Dzięki temu glony te mogą swobodnie rosnąć, zapewniając rybie przetrwanie, gdyż garbiki nie posiadają narządów zdolnych do rozgniatania celulozowych włókien, ani też enzymów potrzebnych do rozłożenia wielu gatunków glonów. Polisyfonia przegrywają konkurencję z niejadalnymi dla ryb algami, dlatego Stegastes nigricans muszą wspomagać ich wzrost właśnie poprzez tzw. ogródki i ich pielenie. Jest to związek o charakterze mutualizmu – obie strony czerpią korzyści o takim stopniu, który praktycznie wzajemnie uzależnia istnienie obu populacji.
Stegastes nigricans là một loài cá trong họ cá thia. Chúng sống ở biển, xung quanh rạn san hô ở độ sâu 12 mét. Chúng có tính phân chia lãnh địa. Chúng chiếm cứ và bảo vệ một phần rạn san hô, thường là xung quanh chỗ trú ngụ của mình. Thông qua việc ngăn chặn các loài cá khác xâm nhập và giúp cho thảm tảo mọc dày lên trong vùng lãnh địa của cá, khiến người ta gán cho những con cá này cái tên thông dụng là "cá nông dân"[1]
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Bài viết chủ đề bộ Cá vược này vẫn còn sơ khai. Bạn có thể giúp Wikipedia bằng cách mở rộng nội dung để bài được hoàn chỉnh hơn. Stegastes nigricans là một loài cá trong họ cá thia. Chúng sống ở biển, xung quanh rạn san hô ở độ sâu 12 mét. Chúng có tính phân chia lãnh địa. Chúng chiếm cứ và bảo vệ một phần rạn san hô, thường là xung quanh chỗ trú ngụ của mình. Thông qua việc ngăn chặn các loài cá khác xâm nhập và giúp cho thảm tảo mọc dày lên trong vùng lãnh địa của cá, khiến người ta gán cho những con cá này cái tên thông dụng là "cá nông dân"
黑眶鋸雀鯛，又稱黑高身雀鯛、黑空真雀鯛，俗名為厚殼仔，為輻鰭魚綱鱸形目隆頭魚亞目雀鯛科的其中一種。
本魚分布於印度太平洋區，包括紅海、東非、萊恩群島、琉球群島、台灣、馬爾地夫、模里西斯、印尼、澳洲、新幾內亞、索羅門群島、斐濟群島、萬那杜、馬里亞納群島、密克羅尼西亞、馬紹爾群島、夏威夷群島、法屬波里尼西亞、復活節島等海域。
水深0至12公尺。
本魚體各鰭皆呈茶褐色，體背部顏色較深。其明顯特徵乃在背鰭最末端的3枚鰭條上有一暗色斑，可能褐色或黑色。在生殖期的雄性個體體色會有所變化，在背鰭鰭棘中間至鰭條部間有一白色寬橫帶，吻至鰓蓋及胸鰭上方則有一白縱帶。背鰭硬棘12枚、背鰭軟條14至17枚、臀鰭硬棘2枚、臀鰭軟條12至14枚。體長可達14公分。
本魚棲息於礁台或礁湖中，非常好鬥，具強烈的領域性。屬藻食性，以藻類為食。
多用以水族觀賞，很少人食用。
