裸头龙䲢属

裸头龙䲢属
科学分类
界：	动物界 Animalia
门：	脊索动物门 Chordata
纲：	辐鳍鱼纲 Actinopteri
目：	鲈形目 Perciformes
科：	龙䲢科 Bathydraconidae
亚科：	渊龙䲢亚科 Bathydraconinae
属：	裸头龙䲢属 Akarotaxis H. H. DeWitt & Hureau, 1980

裸头龙䲢属（学名：Akarotaxis）是辐鳍鱼纲龙䲢科之下一个海鱼的属，其物种皆栖息于南极洲位于南冰洋的大陆架。过往本属只有裸头龙䲢一个物种；后来美国弗吉尼亚海洋科学研究所（VIMS）威廉与玛丽学院的科学家在南极洲西侧半岛冰冷的海域中，发现了本属的另一全新物种“带状龙䲢”（Akarotaxis gouldae）。

分类学

裸头龙䲢属的物种最早于1980年由美国鱼类学家 休·汉密尔顿·德威特（Hugh Hamilton DeWitt）和法国鱼类学家让-克洛德·胡罗（Jean-Claude Hureau）的研究首度描述，当时本属只有裸头龙䲢（Akarotaxis nudiceps）一个物种。这个物种的描述早在1916年，由英国出生的澳大利亚动物学家埃德加·拉文斯伍德·韦特描述为Bathydraco nudiceps，模式产地位于沙克尔顿冰架对出的玛丽皇后地。 The type was collected by the Australasian Antarctic Expedition. The generic name compounds akaro meaning "short" or "small" with "taxis" which means "line" or "row", a reference to the short upper 体侧线, which comprises lees than 10 tubular scales. The 种本名 nudiceps means "naked head", thought to be an allusion to the absence of scales on the head despite Waite not mentioning this trait.

Akarotaxis gouldae was described in August 2024, based off of specimens exclusively found in a 400 km stretch of coastline in the 南极半岛, from 拉佩雷尔湾 in the north to 阿德莱德岛 in the south. The describers refrain from citing this as strong evidence of distribution, as it may be an artifact of 偏差样本. The specific name was coined in honor of the U.S. Antarctic Research and Supply Vessel Laurence M. Gould, and not the namesake of the vessel itself. A. gouldae was coined in the feminine form specifically to honor the ship, reflecting the practice of assigning ships female pronouns.

Description

Akarotaxis has a slender, body which is covered in 鱼鳞 scales and has two lateral lines, the upper lateral line having only 3-9 tubed scales in its anterior section with its posterior part being made up of poredscales which also make up the middle lateral line. The upper rear margin of the operculum has a small hook. They are equipped with small conical teeth arranged in bands. The dorsal fin has 29-33 soft rays while the 鱼鳍 has 25-28 soft rays. Specimens preserved in alcohol have a brown body with a darker head, a pale dorsal fin pale and the other fins being dusky. This species attains a maximum standard length of 13.0 cm（5.1英寸）.

Distribution, habitat and biology

Akarotaxis is found almost all around the Antarctic continent from west of the 阿德莱德岛 to the 罗斯海 where it is a bathydemersal species found at depths between 371至915米（1,217至3,002英尺） on the outer 大陆架 and in deep troughs. It has the lowest known fecundity of the Antractic dragonfishes, laying only 2000 eggs per female. 产卵 takes place from mid to late summer.

Threats

A. gouldae exhibit extremely low 繁殖力. They also associate with the ocean surface. Ergo, the budding Antarctic krill fishery in the region may capture A. gouldae larvae as bycatch, and thus imperil the species.