OVARIAN STRUCTURE AND BATCH FECUNDITY IN LOPHIOMUS-SETIGERUS

The ovarian structure and batch fecundity of anglerfish Lophiomus seti gerus were examined from specimens collected in the East China Sea dur ing March 1991 to September 1995. The right and left ovarian lobes wer e connected at their posterior ends. Stalk-like ovigerous lamellae pro truded from the ovarian wall. During the spawning season, gelatinous m aterial was secreted from the epithelia of both the ovigerous lamellae and ovarian wall, and these epithelia showed morphological changes ac companying the ovarian maturation cycle. Tertiary yolk, migratory nucl eus, and mature stage oocytes occurred in the ovaries between May and November, when females with postovulatory follicles and developing vit ellogenic oocytes were collected also. These results suggested an exte nded spawning season during which females undergo repeated spawnings. When the most advanced oocytes attained the secondary yolk stage, they formed a batch that separated from the adjacent group of smaller oocy tes. Batch fecundity (F) in 20 females with secondary yolk stage ovari es was related to total length (L-T, mm) as F=556.2 L-T(1.157) (300 le ss than or equal to L-T less than or equal to 396). (C) 1998 The Fishe ries Society of the British Isles.