|Breeding of the ark, Anadara broughtonii (Schrenk), in tank|
Kan-No, H. (1963). Breeding of the ark, Anadara broughtonii (Schrenk), in tank. Bull. Tohoku Natl. Fish. Res. Inst. 23: 108-116
In: Bulletin of the Tohoku National Fisheries Research Institute. Suisan-chō Tōhoku-ku Suisan Kenkyūjo: Shiogama. ISSN 0049-402X
Biological phenomena > Metamorphosis
Anadara broughtonii (Schrenck, 1867) [WoRMS]
Breeding of the ark Anadara broughtonii in tank was made in order to make clear its metamorphosis and also to examine the possibility of its artificial propagation. The result was as follows.1) The mature eggs and sperm were spawned by means of repeated thermal stimulation (Kan-no, 1962) and then the eggs were artificially fertilized. At 22-25° C, they developed to D-shaped veliger, 83-99 mu in shell length and 67-74 mu in shell height, about 22 hours after fertilization. The early development is shown in Table 1 and Plate I.2) The larvae were reared in two concrete tanks (I and II) from August 6th to September 14th in 1961, after the method devised by Prof. T. Imai et al. (1949). The rearing records are shown in Table 2 and Fig. 1.3) The first prodissoconch stage lasted for about 13 days until the larvae grew to 130 mu in shell length and 105 mu in shell height, and then umbo began to develop. When the larvae became 190 mu in length and 150 mu in height, the foot developed and before long the larvae crawled on the substrata with both the foot and velum action. The full grown larvae, over 230 mu in length and 180 mu in height, about four weeks after fertilization attached themselves on the substrata by their byssus. The shell size of the attached young was 230-300 mu in length and 180-230 mu in height. The development of larvae is illustrated in Plate II and the growth of the shell is shown in Table 3.4) The estimated numbers of collected young were 168,000 in Tank I and 43,000 in Tank II. The survival rates were 33 and 10 per cent respectively.5) The young spat were continuously reared in the tanks with running sea water to the end of August of the following year. At the end, they grew to 2-25mm in shell length and 1-17mm in shell height but with a few survivals. Growth of the young is shown in Table 4.