Nomorhamphus rex

Kraemer, Janina, Thieme, Philipp, Hadiaty, Renny Kurnia & Herder, Fabian, 2019, Structure of the andropodium of the viviparous halfbeak genus Nomorhamphus (Atherinomorpha: Beloniformes: Zenarchopteridae), endemic to Sulawesi, Indonesia, Raffles Bulletin of Zoology 67, pp. 247-259 : 253

Nomorhamphus rex

( Fig. 6A, C )

Pigmentation of anal fin. Distal tips of anal-fin rays greyish or black in most males; range and intensity of pigmentation varies between individuals; cryptoplica and fin rays slightly pigmented, small melanophores.

Andropodium. 1 st anal pterygiophore thickened, not angled anteriorly. 2 nd fin ray with 3–4 segments proximal to spinae; segment 3 or 4 greatly elongate, approximately half the length of the entire ray, with an irregular dorsal and ventral row of small sub-segments (squares and rectangles) of different sizes, each sub-segment approximately 1/3 the height of segment 3 or 4, number of sub-segments variable; spiculus sickle-shaped, clearly segmented, short, upright position and curved (degree of curvature varies between specimens), its proximal and middle segments in contact with the distal tip of the third anal-fin ray. 3 rd fin ray with segment 3 greatly elongate, approximately half the length of the entire ray, constricted longitudinally, composed of three longitudinal rows, each row approximately 1/3 the height of the respective segment; segments 4 to tip short, tip nearly straight. 4 th fin ray with segment 4 composed of three longitudinal rows, greatly elongate; following segments short. 5 th fin ray thickened in larger males.

Figures

Fig. 6. A, B, Diagrammatic representation of andropodium of (A) Nomorhamphus rex,ZFMK 44945, 35.0 mm SL and (B) N. kolonodalensis, ZFMK 49103, 40.3 mm SL. C, D, Rendered image of andropodium of (C) N. rex, ZFMK 44944, 41.2 mm SL and (D) N. kolonodalensis. Scale bar = 1 mm. Bone stippled. Arrowheads point (A) to the elongate fourth segment of the second anal-fin ray and to the characteristic, sickle-shaped spiculus of N. rex and (B) to the thin, elongate spiculus of N. kolonodalensis.