Table 1 in Taxonomic and Biogeographical Status of Three Species of the Spider Crabs of the Genus Acanthonyx Latreille, 1828 (Majoidea: Epialtidae) as Determined by DNA Barcoding and Morphological Analyses Along the Western Atlantic

Table 1. Morphological characters used to compare the species Acanthonyx dissimulatus, A. petiverii and A. scutiformis
CharactersResultsCarapaceshape; distribution and type of setae and tuberclesCarapace elongate, subpentagonal; presence/absence of tufts of hair and tubercles; size and thickness of setae variableRostrumshape; type of setaeShort, deflexed and bifid; setae size and thickness variableOrbits *angle in relation to the rostrumLateral angles obtuse; preorbital lobes not pointedEyespresence or absence of setaeDorsal surface with short setae, sometimes absentPreorbital toothpresence or absence; type of setaeTeeth elevated, not pointed; size and thickness of setae variablePostorbital toothpresence or absenceAbsentHepatic Regionshape; angles indorsal view; presence or absence of setaeWith almost rectangular angles, lateral lobes curved forwards and upwards; rectangular angle in specimens identified as A. dissimulatus; inclined forward in specimens identified as A. scutiformisGastric, cardiac and intestinal regionspresence or absence of setae and tubercles; distribution and type of setaeGastric region with 2 setiferous tubercles on the protogastric, 1 on mesogastric; slightly elevated in specimens identified as A. dissimulatus. Cardiac region not evident; absent or obsolete tubercle.Brachial Regionpresence or absence of teeth; type of setae2 small teeth not pointed, with short and long setae; setae can be absent in specimens identified as A. scutiformisBasal article of antennashape; articles position in relation to the rostrum; distribution and type of setaeBase wider than the extremity; the following 2 articles subcylindrical; distal end of 2° article with long setae; 3° article with tufts of setae on the inner margin. Setae can be absent in all species.Chelipedssize; presence or absence of gap between fingersShort, considerably enlarged in males; less strong, short and smaller in females.Ischium*; merus*; carpus*; propodus; dactyluspresence or absence of setae, tubercles, crest and teeth; type of setaeIschium:1-5 thin setae; merus: 3 setiferous lobes at the distal end, 1-2 spines on the proximal dorsal surface; carpus: a setiferous external crest, 3 setiferous tubercles. Propodus of chelipeds gaping in adult male, dentate on outer surface; sometimes a bigger central tool in large males indentified as A. dissimulatus and A. petiverii.Pereopodssize; distribution and type of Subchelate, more pronounced from the 4° to the 1° pair, posteriorly decreasing in setae size; setae sometimes absent.Ischium*; merus; carpus; propodus; dactylusshape; presence or absence Merus: 3 lobes in distal end of the 1° and 2° pereopods with or without setae; of setae, lobe, tubercles, carpus: subtriangular in the last two pereopods; propodus: compressed and spines; distribution and type subtriangular; dactylus: ventral surface with 2 rows of minute spines of setaeThoracic sternumshape; position; presence or absence of setaeSmoothAbdominal somitesdegree of fusion; shape; presence or absence of setae4-5 united in both genders, triangular abdomen in males, telson triangular in both gendersMale first pleopodshapeExtremity with a subtriangular lobe with minute spines