Figure 3

Reproductive behavior of the paradise fish. (A) Male paradise fish building nest, by ejecting mucus covered bubbles (A,B). (B) Paradise fish males show lateral spread display (LSD) behavior towards female fish in courtship. (C,D) Paradise fish courtship behavior: female fish check nest (C) or refuse male’s invitation by showing aggressive displays (OPE—opercular erection, LSD), vibrating movement (VIB) towards male fish (D), or even escape (ESC). (E) Paradise fish performing circling (CIR) followed by anabantoind embrace (ANE). (F–K) Step by step illustration of courtship behavior at M. opercularis. (F) Male fish building nest (A,B), (G) male fish starts lateral spread display (LHH), (H) male leads female to the bubble nest (LEN), (I) female shows a vertical waggle (VEW) followed by circle swimming (CIRC) under and toward nest, (J) anabantoid embrace (ANE) and release of gametes, (K) swimming inhibition (SIN). Steps I to K are repeated approximately 12–15 times, until the spawning process is finished (2–3 h). Drawing credit: Renáta Hamar, photo credit: Anita Rácz.