PEREZ FAREANTE: AMERICAN SOLENOCERID SHRIMPS 



Burkenroad subdivided the group into two sec- 

 tions: section 1, with orbital spines, to which only 

 H. robustus was assigned, and section 2, without 

 orbital spines, to which the western Atlantic H. 

 modestus and the Indo-West Pacific H. lucasii 

 were referred. As stated above, the former species 

 is here transferred to the genus Pleoticus, and 

 the latter two, together with the amphi-Atlantic 

 H. affinis (which Burkenroad considered as "very 

 doubtfully distinct" from//, modestus), are placed 

 in the genus Hadropenaeus. 



Group III. This group comprised the species 

 with pterygostomian but lacking branchiostegal 

 spines, and with the epigastric tooth separated 

 from the rostral teeth by a long interval. The east- 

 ern Pacific//, diomedeae and the Indo-West Pacif- 

 ic H. sibogae and H. triarthrus were included, but 

 these three species are referred here to the genus 

 Haliporoides Stebbing 1914. 



Group IV. This assemblage contained those 

 species that are armed with branchiostegal 

 spines, and have the epigastric and first rostral 

 teeth separated from the remaining rostral teeth 

 by a conspicuous interval. It was subdivided into 

 two sections characterized by the presence or 

 absence of pterygostomian spines. In section 1, 

 Burkenroad cited Hymenopenaeus laevis, found 

 on both sides of the Atlantic and in the Indo-West 

 Pacific, and H. doris and H. nereus of the Ameri- 

 can Pacific; in section 2, he included the Atlantic 

 H. aphoticus and H. debilis and the Indo-West 

 Pacific//, aequalis, H. obliquirostris, H. neptunus, 

 and H. propinquus. Since the publication of Bur- 

 kenroad's work, one species, the Indo-West Pacific 

 H. sewelli, has been added to section 1, and three 

 have been added to section 2: one from the eastern 

 Atlantic, H. chacei, and two from the Indo-West 

 Pacific, H. fattahi, and H. halli. These species 

 are included in Hymenopenaeus as restricted 

 here, and their separation into two sections is 

 recognized. 



Burkenroad also discussed under Hymeno- 

 penaeus the two following Indo-West Pacific 

 species: Haliporus villosus Alcock and Anderson 

 1894 (syntype illustrated in Alcock and Anderson 

 1896), and Haliporus taprobanensis Alcock and 

 Anderson 1899 (holotype illustrated in Alcock 

 1899b). He indicated that the former perhaps 

 would merit being placed in an independent 

 group, and pointed out that although the latter 

 shares several characters with members of Group 

 III, it differs from them in other basic features. 

 Our knowledge of//, villosus prior to Kensley's 



(1968) study was limited to the brief description 

 by Alcock and Anderson (1894) and their illustra- 

 tion published in 1896 (plate 26, figure 1). The 

 lack of detail in the figure of the telson, exhibiting 

 no movable spines, was probably responsible for 

 Burkenroad's assigning this shrimp to the genus 

 Hymenopenaeus. Kensley presented a detailed 

 description and several illustrations which dem- 

 onstrate that this species exhibits two basic fea- 

 tures characteristic of the genus Haliporus (as 

 restricted by Burkenroad 1936): in addition to the 

 podobranchia on the second maxilliped, another, 

 small one is present on the third maxilliped, and 

 the telson is armed with movable spines situated 

 anterior to the fixed pair. My examination of two 

 specimens of//, taprobanensis has shown that the 

 same characters are present in them; thus, in 

 respect to these two features, both this species and 

 H. villosus are more closely allied to the members 

 of Haliporus than to those assigned to Hymeno- 

 penaeus. It should be pointed out, however, that 

 H. villosus and H. taprobanensis differ from Hali- 

 porus curvirostris Bate 1881, the type-species, in 

 several characters (e.g., shape of rostrum, number 

 of podobranchiae posterior to the second maxilli- 

 ped, carinae present on the carapace) which seem 

 to me to be of supraspecific significance. Conse- 

 quently, I believe that a study of adequate mate- 

 rial might demonstrate that they should be rele- 

 gated to separate monotypic genera. 



Although the illustration of the entire animal 

 of//, villosus by Alcock and Anderson (1896) and 

 that by Kensley (1968) leave little doubt that both 

 correspond to the same species, the specimens 

 available to the former authors were densely 

 covered by setae, as they explicitly stated, where- 

 as that studied by Kensley as well as the speci- 

 mens examined by me are glabrous. The mate- 

 rial available to Alcock and Anderson was from 

 the Laccadive Sea, off southwest India; Kensley's 

 specimen was caught off southwest of South 

 Africa, and the two at my disposal were collected 

 off eastern Madagascar. 



All five genera (together with Haliporus and 

 Solenocera) are believed to have arisen from a 

 common solenoceroid ancestor, some of the char- 

 acters of which are presented in the accompany- 

 ing dendrogram. In the latter only the newly 

 acquired characters or those modified or lost in 

 each lineage are indicated. As shown in the 

 dendrogram, one of the lines arising from the 

 solenoceroid ancestor led to Haliporus, apparently 

 not only the most primitive solenocerid, but 



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