Fig. 2

Detailed internal and external morphology of the leg tips of pereopods 3 and 4 of male Sinelobus sp. a, a' SBF-SEM scans showing the interior structure of the left pereopod 3 (thread-spinning), posterior and anterior view. b, b' conventional SEM images of left pereopod 3, posterior and anterior view. c, c' SBF-SEM scans showing the interior structure of left pereopod 4 (non-thread-spinning), posterior and anterior view. d, d' conventional SEM images of left pereopod 4, posterior and anterior view. Abbreviations: ds, dactylar setae; nds, nervous divisions innervating dactylar setae; nps1-4, nervous divisions innervating propodal setae 1–4; ntp, nervous divisions innervating terminal pore; nts, nervous divisions innervating base of terminal spine; pm1 and pm2, propodal muscles 1 and 2; ps1-ps4, propodal setae 1–4. The white square in a indicates the area shown in Fig. 4a, b. Scale bars, 15 μm for a, a’, c, c’, 10 μm for b, b’, d, d’