PEREZ FARFANTE: REVISION OF PEN AEID SHRIMP GENUS PENAEOPSIS 



Maximum lengths. — 160 mm tl (Crosnier and 

 Jouannic 1973). Largest specimens examined by 

 me: males 23 mm cl, about 107 mm tl; females 33 

 mm cl, about 138 mm tl. 



Geographic and bathymetric ranges. — Indian 

 Ocean (Figure 6), from the Bay of Bengal (Anda- 

 man Sea; off Madras) through the Arabian Sea 

 (off Cochin) to the Gulf Aden (off Berbera) and 

 south to off Mozambique and Madagascar. It has 

 been found at depths between 183 and 677 m. 



Affinities. — Penaeopsis jerryi differs from the 

 closely related P. rectacuta, from the South China 

 Sea, Philippines, and Indonesia, mainly by the 

 position of the hepatic spine, the length of the 

 branchiocardiac carina, and features of the 

 thelycum. 



In P. rectacuta the hepatic spine is located at a 

 level distinctly ventral to, instead of about the 

 same level as, that of the antennal spine, and the 

 branchiocardiac carina ends farther from the 

 hepatic sulcus than it does in P. jerryi. 



The petasmata of the two species, although 

 similar, differ in that the rib of the dorsolateral 

 lobule in P. rectacuta is straight distally and ter- 

 minates proximally in a subcircular process, 

 whereas in P. jerryi the rib sometimes turns lat- 

 erally and often ends in a semicircular process. 



In P. rectacuta the thelycal plate of sternite 

 XIV is usually roughly trapezoidal, with the an- 

 terior border almost straight on each side of the 

 posteromedian projection of sternite XIII, and the 

 anterolateral corners forming angles, whereas in 

 P. jerryi this plate is roughly elliptical with the 

 anterior border arcuate and the anterolateral and 

 posterolateral comers arched. Finally, in P. jerryi 

 the median plate of sternite XIII is subsemicircu- 

 lar [e.g., in females illustrated by Alcock (1906, 

 pi. 6: fig. 19a) and by Ivanov and Hassan (1976, 

 fig. 3) as well as in most of those examined by 

 me], or occasionally weakly trilobed as in the 

 specimen figured by Ramadan (1938, fig. 12b). In 

 a few females I have studied, the plate, although 

 almost semicircular, is produced into a minute 

 anteromedian spine, its general shape thus being 

 quite different from the cordiform median plate of 

 P. rectacuta. 



In occasional specimens of P. jerryi, the basis of 

 the second pair of pereopods is armed with a dis- 

 tomesial spine (Alcock 1901a), a feature that has 

 not been observed in the other species. Also, as 

 pointed out by Ramadan (1938) and confirmed by 



my observation, some individuals bear less than 

 the tree typical pairs of movable spines on the 

 telson (one or two pairs) and I found one with the 

 spination asymmetrical. 



Remarks. — On the basis of the scant information 

 provided by Balss ( 1925) it has not been possible 

 for me to determine the identity of the two 

 females he recorded as "Parapenaeus rectacutus" 

 from the Nicobar Islands, Bay of Bengal. Accord- 

 ing to him, the telson bears two pairs of movable 

 spines, a characteristic of three of the five Indo- 

 West Pacific members of the genus — Penaeopsis 

 balssi, P. challengeri, and P. eduardoi. In the 

 same work, however, he identified specimens be- 

 longing to P. balssi, which were taken off east 

 Africa, as "Wenaeopsis challengeri"; con- 

 sequently, it seems very unlikely that the two 

 females belong to P. balssi. It also seems improba- 

 ble that they are members of P. challengeri or P. 

 eduardoi because these species are not known to 

 occur in the Indian Ocean. Balss added that in his 

 specimens the second pair of pereopods is armed 

 with spines; such have been observed only in oc- 

 casional individuals of P. jerryi; but three, not 

 two pairs of movable telsonic spines are charac- 

 teristic of this shrimp typically. Balss' specimens, 

 however, may prove to be atypical P. jerryi be- 

 cause this shrimp is the only species of the genus 

 that has been recorded from the area. 



Commercial importance. — Survey fishing off the 

 west coast of India at depths between 175 and 375 

 m (George 1966, 1969; Jones 1967; Longhurst 

 1971) demonstrated the presence of P. jerryi in 

 sufficient numbers for possible commercial 

 exploitation of this shrimp. Crosnier and Jouan- 

 nic (1973) noted that this species eventually will 

 become commercially fished off Madagascar. 



Penaeopsis rectacuta (Bate 1881) 



Figures 6, 20-27 



Penaeus rectacutus Bate 1881:180 [V holotype, 

 BNMH; type-locality, between Bohol and Cebu, 

 Philippines, 10°14' N, 123°54' E, 95 fathoms 

 ( \1 Am), Challenger stn 209]; 1888:266 [part], pi. 

 36, fig. 2, 2", 2 p [fig. 2z = P. eduardoi]. Estam- 

 pador 1937:493. Domantay 1956:363. Perez 

 Farfante 1977b:172. 



Parapeneus rectacutus. Alcock 1905:520 [part, 

 references only]. 



741 



