PEREZ FARFANTE: REVISION OF GENUS PSEUDARISTEUS 



April 1899; Siboga Exped. stn 52]. De Man 1913, 

 pi. 2, fig. 5, 5a-c. Ramadan 1938:48. Anderson 

 and Lindner 1945:301. Burukovsky 1974:48. 

 Pseudaristeus sibogae. Crosnier 1978:83, figs. 27a, 

 30a-c; 1984:22. De Freitas 1985:12, fig. II-5, 

 A-H. 



Material. 



Madagascar— 1 9, MP, NW of Ankazomanga; 

 21°26'30"S, 43°11'00"E; 810-1,020 m; 26 November 

 1973; Vauban stn 92. 1 o- 1 9, MP, SW of Bale des 

 Assassins; 22°16'48"S, 42°56'00"E; 1,200 m; 30 

 November 1973; Vauban stn 109. 



Indonesia— 9 holotype. 1 9, USNM, S of Pulau 

 Muna, Sulawesi (Celebes); 5°31'30"S, 122°22'40"E; 

 834 m; green mud; 16 December 1909; Albatross stn 

 5646. 10-2 9, USNM, Selat Butung, Sulawesi 

 (Celebes); 5°34'00"S, 122°18'15"E; 950 m; green 

 mud; 16 December 1909; Albatross stn 5647. 1 9, 

 USNM, off southern Buru; 3°47'15"S, 126°23'40"E; 

 946 m; fine gray sand; 10 December 1909; Albatross 

 stn 5638. 



Diagnosis.— OTptic calathus long, mesial margin 

 1.5-1.7 times distal width. Anterolateral carina lack- 

 ing. Posterior extremity of hepatic sulcus turned 

 ventrally. Third article of antennular peduncle not 

 expanded laterally; males with ventral antennular 

 flagellum never sinuous; ultimate article of third 

 maxilliped straight and slightly broadening proximo- 

 mesially before tapering to apex. Pereopods covered 

 with minute setae. Adult petasma unknown. Thely- 

 cum with plate of sternite XIV moderately long and 

 produced in short anterolateral hoods; median plate 

 of sternite XIII relatively short (not nearly reach- 

 ing spine on sternite XII) and broad (maximum 

 width 0.60-0.70 length) but not expanded postero- 

 laterally in conspicuous prominences. 



Description.— Body slender, densely studded with 

 minute setae. Rostrum in males straight, moderately 

 long, 0.48 and 0.57 CL in 2 specimens, 21 and 22 

 mm CL, respectively, and roughly lanceolate; in 

 females longer, in one 37 mm CL its length 1.07 CL, 

 rather deep and usually convex, occasionally almost 

 straight basally, styliform and moderately upturned 

 anteriorly. Rostral plus epigastric teeth 3; 2 rostral 

 teeth in males situated at 0.1-0.2 and 0.4 RL respec- 

 tively, basally in females. Adrostral carina strong, 

 in both males and females extending just anterior 

 to second tooth. Antennal spine sharp; branchios- 

 tegal spine longer than antennal, acutely pointed. 

 Cervical sulcus crossing postrostral carina at about 



0.45 CL from orbital margin, with ventral part turn- 

 ing anteriorly; accompanying carina blunt, except 

 for sharp, arched ventral extremity; rather weak 

 postcervical sulcus reaching, but not crossing, post- 

 rostral carina at 0.7-0.8 CL from orbital margin. 

 Postrostral carina, extending 0.8-0.9 CL from or- 

 bital margin, well marked and sharp to cervical 

 sulcus, low and blunt posteriorly, and followed by 

 small tubercle situated near posterior margin of 

 carapace. Anterolateral carina lacking; gastro- 

 orbital carina strong; antennal carina relatively 

 short; branchiostegal-hepatic carina long, raised and 

 sharp. Orbito-antennal sulcus shallow; deep hepatic 

 sulcus fusing with branchiocardiac sulcus before 

 turning obliquely almost ventrad, forming small 

 branch nearly reaching margin of branchiostegite; 

 branchiocardiac sulcus, accompanied by strong 

 carina, deep and long, extending posteriorly to near 

 margin of carapace; blunt, dorsally concave ridge 

 (disposed dorsal to posterior part of hepatic sulcus 

 and anterior part of branchiocardiac sulcus) de- 

 limited dorsally by groove, latter deep and abutting 

 cervical sulcus anterodorsally but becoming shallow 

 posteriorly and indistinct close to postcervical 

 sulcus. 



Eye (Fig. AE) with optic calathus long, length of 

 mesial margin 1.50-1.75 times distal width; mesial 

 tubercle small and situated between distal 0.40 and 

 0.55 length of margin. 



Antennular peduncle with stylocerite produced in 

 sharp, slender spine falling conspicuously short to 

 almost reaching mesial base of distolateral spine; lat- 

 ter acutely pointed; third article never produced 

 laterally. Dorsal flagellum about 0.4 length of anten- 

 nular peduncle, reaching between distal 0.25 and 

 0.20 of scaphocerite; ventral flagellum long and 

 straight along entire length. 



Scaphocerite extremely long, exceeding anten- 

 nular peduncle by about 0.30-0.35 its own length; 

 strong lateral rib ending in sharp spine falling con- 

 siderably short of distal margin of lamella. Anten- 

 nal flagellum broken in specimens examined. 



Third maxilliped in both sexes with penultimate 

 article convex dorsally, slightly flattened ventral- 

 ly, and not produced in distal process; ultimate 

 article also convex dorsally, slightly excavate ven- 

 trally, and slender but broadening slightly from 

 relatively elongate, narrow base before tapering to 

 rather blunt apex. 



All pereopods covered with minute setae. First 

 and second pereopods with compressed merus bear- 

 ing distomesial spine. 



Abdomen with dorsomedian carina extending 

 from fourth through sixth somites, carina quite low 



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