Known range. — Between Capes Hatteras and 

 Lookout, N.C., through Caribbean Sea and "West 

 Indies to Surinam ; Bermuda. 



Remarks. — Larval stages from Bermuda that 

 probably belong to this species were described by 

 Gurney (1943b). From observations at Bermuda, 

 Wheeler (1937) described characteristic swarm- 

 ing of this species at about an hour after sunset, 

 with monthly maxima on the 2d and 26th days of 

 the lunar month. 



Genus Xiphopeneus Smith, 1869 



Burkenroad, 1934b, p. 102. 



Xiphopeneus kroyeri (Heller) 



Figures 18-20 



Peneue kroyeri Heller, 1862, p. 425, fig. 51. 



Xiphopeneus kroyeri: Burkenroad, 1934b, p. 103, flg. 12 

 (rev.). — Schmltt, 1935a, p. 132, fig. 5.— Holthuis, 1958, p. 70, 

 fig. 7. 



Recognition characters. — Carapace and abdo- 

 men smooth. Rostrum laterally compressed, 

 sinuous, armed with usually five dorsal teeth at 

 base, styliform tip greatly elongated beyond 

 antennal scales and varyingly elevated. Carapace 

 with a single ejjigastric tooth behind rostral series 

 on rounded postrostral carina extending from base 

 of rostrum to near posterior border; no trans- 

 verse suture in adults; anterior cervical groove 

 reaching anterior margin and continuous with 

 branchiocardiac groove reaching almost to pos- 

 terior border; hepatic and antennal spines present. 

 Antennal flagella much longer than body ; anten- 

 nal scale extending beyond tip of antennular 

 peduncle. Inferior antennular flagellum up to 50 

 percent length of antenna. Exopodites of second 

 and third maxillipeds slender. 



Last two pairs of legs elongate, flagelliform, 

 with dactyls many jointed. 



Figure 18.- -Xiphopeneus kroyeri (Heller). Anterior 

 pail of animal in lateral view, approximately X 3.2 

 after Holthuis, 1959). 



Figure 19. — Xiphopeneus kroyeri (Heller). Petasiua of 

 adult male, ventral view, 1 mm. indicated. 



Figure 20. — Xiphopeneus 

 kroyeri (Heller). Thely- 

 cum of female, filled 

 sperm sacs showing 

 through abdominal in- 

 tegument (after Burken- 

 road. 1934b). 



Fourth to sixth abdominal segments carinate, 

 with small dorsal tooth at posterior end of carina 

 on each segment; sixth segment with carina high 

 and deep. Telson tapering to acute tip. 



Petasma of male with distolateral corners 

 greatly produced as hornlike projections, open 

 along distal margins on thoracic face. Thelycum 

 of female externally appearing as an unpaired 

 plate extending forward from last thoracic 

 somite. 



Measurements. — Length of body : 127 mm. 



Variations. — The rostrum is somewhat longer in 

 females than in males, and varies with age. In 

 individuals with carapace length under 9 mm., 

 the rostrum is shorter than the carapace, but be- 

 yond this size it is usually longer than the 

 carapace. 



Color. — Whitish, ventral part yellowish, occa- 

 sionally with yellow over whole body but most 



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