The males of Orygma luctuosum jump on the female and wrap their fore and mid legs around the female thorax [see Additional file 6] (or visit the following website [ 62]).
His jeans were worn and bulging mid-leg, as though he spent his days kneeling.
Using 14 males, we confirmed that male behaviors after mounting were not affected by the w-bar: there was no difference in the frequency of the male's mid-leg movements (used for signal production) between normal matings and matings with w-bar equipped females (paired t-test, t(13) = 0.35, p = 0.73).
G. gracilicornis males produce ripple signals with their mid-legs stretched forward, vibrating vertically (Figure 3 and Video S1).
Males produce irregular numbers of pulses per bout with their mid-legs stretched wide (Table S1 and Video S1).
G. gracilicornis males mounted on the backs of females often produce ripple signals by hitting the water's surface with their stretched mid-legs.
At this final stage, relatively regular numbers of pulses are produced per bout, with mid-legs stretching parallel to each other (Videos S1 and S2).
At this stage, the male produces pulses at irregular intervals, with mid-legs stretched forward, parallel to each other (Video S1).
The basic unit of all signaling consisted of a single tap on the water's surface with the mid-legs (we call it a pulse, because it created a short pulse of ripples on the water's surface, Figure 3ABC; Video S1).
In an apparent response to the female morphological adaptation, males of this species added to their typically violent coercive mounting of the female new post-mounting, pre-copulatory courtship signals produced by tapping the water's surface with the mid-legs.
Water walkers maintain the ancestral appendage plan where the mid-leg is shorter than the hind-leg (L2<L3) whereas water rowers show a derived leg plan where the mid-leg is longer then the hind-leg (L2>L3).
