Morphology of camouflage by encrustation in the spider crabs Schizophrys dahlak and Hyastenus hilgendorfi (Decapoda: Brachyura: Majoidea: Epialtidae) from the Suez Canal, Egypt Author Osman, Marwa M. Author Sallam, Wafaa S. Author Madkoura, Fedekar F. Author Wicksten, Mary K. text Journal of Natural History 2021 2021-11-10 55 33 - 34 2047 2064 journal article 3299 10.1080/00222933.2021.1973132 9d69522b-dc11-4e0b-b6d4-65e7e7dcf9e7 1464-5262 5727780 Schizophrys dahlak Griffin and Tranter, 1986 The carapace of S. dahlak is characterised by two distinguishing features: surface protuberances of different heights and intervals on which clusters of setae are found ( Figure 2 (a)), and patches of denticles with a tusk or tooth shape and a blunt tip. There are three patterns of distribution, with the first pattern being the most common ( Figure 2 (b–d)). Pattern (1) Single denticles found in rows, L 1.7 μm and W 0.5 μm. Interval 4 μm, widely distributed on all regions of the exoskeleton ( Figure 2 (b)). Pattern (2) Paired denticles found in rows, L 2.7 μm and W 1 μm; interval 6.5 μm, found on left and right branchial regions of carapace ( Figure 2 (c)). Pattern (3) Twelve spinules of L 0.3 μm, elliptical in shape, facing the base of a single denticle of L 2.03 μm, interval 3 μm. Commonly distributed on frontal region of carapace and on abdomen ( Figure 2 (d)). Eight setal types were discovered and photographed on the exoskeleton. No notable difference was seen between males and females or among the size ranges. A description is provided for each setal type observed, including average width and length, presence of outgrowths and their average length, as well as areas of the integument where the setal type was mainly encountered. No pores were present on any of the described forms. All setal forms showed infracuticular articulation (an articulation in the form of a socket, which is drawn into the general cuticle).