Stratiotes Thomson, 1899

Rahayu, Dwi Listyo, 2005, Additions to the Indonesian fauna of the hermit crab genus Pseudopaguristes McLaughlin and a further division of the genus Paguristes Dana (Crustacea: Decapoda: Paguroidea: Diogenidae), Zootaxa 831, pp. 1-42 : 4-5

Genus Stratiotes Thomson, 1899

Stratiotes Thomson, 1899: 185 .

Type species. Stratiotes setosus Thomson, 1899 , junior subjective synonym of Pagurus setosus H. Milne Edwards, 1848 .

Diagnosis. Twelve pairs of bi­ or quadriserial gills; no pleurobranch on fifth or eighth thoracic somites. Shield well calcified, with rostrum well developed or reduced. Ocular acicles well developed or reduced, simple, bi­ or multidenticulate. Antennal peduncle with supranumerary segmentation; acicles elongate, spinose or spinulose. Mandible with unarmed mesial margin, palp often indistinctly 3­segmented. Maxillule with external lobe of endopod prominently recurved. Maxilla with elongate endopod. First maxilliped with well developed epipod. Second maxilliped without distinguishing characters. Third maxilliped with basal segments approximate or somewhat separated; crista dentata usually well developed; accessory tooth absent; merus usually with 1 or more spines; carpus, propodus and dactyl usually unarmed.

Chelipeds equal, subequal or unequal, with left considerably larger than right; similar or dissimilar in armament; claws corneous, fingers opening in horizontal or oblique plane. Fourth pereopods subchelate or weakly semichelate, with or without preungual process developed at base of claw. Fifth pereopods chelate.

Males with paired gonopores; first and second pleonal somites each with pair of pleopods modified as gonopods; unpaired, unequally biramous left pleopods on pleomeres 3–4, pleopod 5 with external ramus well developed, internal ramus rudimentary. Females with paired gonopores; first pleonal somite with pair of modified pleopods; following 3 pleomeres with unequally biramous left pleopods; fifth pleopod as in male; brood pouch usually well developed, occasionally entirely absent.

Uropods asymmetrical. Telson with lateral incisions; posterior portion divided by median cleft into 2 subequal to markedly unequal lobes.

Remarks. Thomson (1899) established the genus Stratiotes for Pagurus setosus Filhol 1885 , and mentioned that it appeared to be allied to Diogenes because of the unequal chelipeds (left much larger than right) but differed in the absence of the intercalary rostral process. Forest and McLaughlin (2000) discussed the status of Stratiotes and mentioned the opinions on this genus expressed by several authors such as Alcock (1905) and Thompson (1930). As the gill number was not examined, these authors were not aware that the type species, Stratiotes setosus , which is in fact synonymous with Paguristes setosus , had only 12 pairs of gills (absence of the pleurobranch on the fifth and eighth thoracic somites). For more than a century the genus Stratiotes was considered a junior synonym of Paguristes . Now that it has been confirmed that Paguristes setosus (H Milne Edwards) possesses 12 pairs of gills, the genus Stratiotes is reinstated.

Among the species included in the genus Paguristes s.l in the collection of the Muséum national d’Histoire naturelle, 13 species have been found to have 12 pairs of gills. Therefore, they are transferred, herein, to the genus Stratiotes ( Table 1 ).

Paguristes hispidus A. Milne Edwards & Bouvier, 1892 MNHN Pg 2927 Stratiotes hispidus n. comb.

Tables

TABLE 1. The species of Paguristes sensu lato transferred to Stratiotes.

Species	Material examined	Current status
Paguristes pilosus (H. Milne Edwards, 1836)	MNHN Pg 5573	Stratiotes pilosus n. comb
Paguristes setosus (H. Milne Edwards, 1848)	MNHN Pg 5570	Stratiotes setosus n. comb.