イソギンポBlennius yatabei Jordan et Snyderに就いて

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Blennius yatabei, a Japanese representative of the tropical blennioid fishes, is not ovoviviparous but oviparous as in the case of Dasson elegans (Steindachner)(cf. Zool. Mag. Tokyo, 59, 17.) The cirrus attached to the upper part of the eye is variable in length. Generally, in the young or female, it is about equal to or slightly longer than the diameter of the eye. In the mature male, however, it is much longer and sometimes extends beyond the base of the 2nd dorsal spine when depressed (Fig. 1). In both sexes, this cirrus is usually branched on its inner ridge. But several branches are sometimes found also on the outer ridge, and further, in exceptional case, a few more are found even on the second inner ridge (Fig. 2). In the male, each of the 1st and the 2nd anal spines has one triangular or round pad respectively, which is provided with many longitudinal wrinckles. The urogenital sinus opens at the tip of a cone behind the anus. The anus is surrounded with the radial folds. From each side of the urogenital cone, a low and short fold extends laterally to make a cross fold passing the cone, just in front of the anal insertion (Fig. 3, A). The pads appear in very young individuals. In a male about 25 mm long to the caudal base, the pad of the 1st anal spine is already apparent, but the other one is not yet developed, although the skin of the 2nd anal spine somewhat expands laterally to the extent that the spine itself looks flattened. The wrinckles on the pads develop gradually with the growth of the fish, and in the large mature male, they are very numerous and fine. The function and the structure of the pads are unknown. In the female, the pads are lacking and the features of the urogenital opening are very much like those of the female of Dasson elegans (Fig. 4).
社団法人日本動物学会の論文
1950-09-15

イソギンポBlennius yatabei Jordan et Snyderに就いて

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