FIGURE 2 in Toward a unified taxonomy of Niphargus (Crustacea: Amphipoda): a review of morphological variability

FIGURE 2. Variability of a head. A: well developed rostrum (the arrow indicates the tip of the rostrum), Niphargus rostratus (after Sket 1971); B: extremely narrowed and elongated genal lobes N. pupetta (after Sket 1971); extraordinary spiniform setae of N. balcanicus (after S. Karaman 1932). The arrow indicates the line along which the head length was measured.