NO. 4 schmitt: stomatopods 137 



SYSTEMATIC DISCUSSION 



Order StOMATOPODA 



Family Squillidae 



Key to the Genera of Stomatopods Known from the 

 West Coast of America^^ 



A^. Articulation between the merus and ischium^^ of the raptorial claw 

 terminal (normal) ; merus grooved inferiorly for the reception 

 of the propodus throughout its length ; propodus finely pectinate, 

 or with a series of fixed spines along outer margin of dorsal sur- 

 face; dactylus not inflated at base, except in the one genus 

 Coronida. 



B^. Carapace with well-marked carinae; cervical groove defined 

 across dorsum of carapace; first 5 abdominal somites with 

 longitudinal carinae; raptorial dactylus armed with teeth on 

 inner margin Squtlla, p. 139 



B^. Carapace without carinae '^"^ cervical groove not extending across 

 dorsum of carapace ;2''' first 5 abdominal somites without lon- 

 gitudinal carinae.2'^ 



25 This key is largely that of Kemp (Mem. Indian Mus., Vol. 4, No. 1, p. 16, 

 1913). Only two of the known genera of stomatopods do not appear in the key here 

 given, Coronidopsis and Odontodactylus. 



The former is known only from the unique type, C. bicuspis Hansen (Siboga 

 Exped., Monog. 35, Lief. 105, p. 19, pi. 1, fig. 7a-ff, 1926), 43 mm. in length, from 

 Buton Strait, between Celebes and Flores, Dutch East Indies. Classified near Coro- 

 nida, it is at once distinguished by "its remarkable rostral plate which is anteriorly 

 divided by a rather deep incision into two long, acute teeth." The raptorial dactylus 

 is not inflated at the base, and is armed with four teeth, including the terminal one. 



Odontodactylus (see Kemp, Mem. Indian Mus., Vol. 4, No. 1, pp. 133 and 204, 

 1913) is known from several species from the Indo-west-Pacific and one from the 

 Atlantic. This genus stands close to Gonodactylus and, if found on the west coast 

 of America, it would have appeared in the following key in Section A- along with 

 Gonodactylus. Unlike Gonodactylus, the raptorial dactylus is armed with teeth on 

 its inner margin. As in that genus, the raptorial dactylus is inflated at the base. 



26 This articulation is given by some authors (see Balss, Bronns Klassen und 

 Ordnungen des Tierreichs, Vol. 5, Abt. 1, Book 6, Pt. 2, Stomatopoda, p. 21, 1938) 

 as between the basis and the ischiomerus, the question being whether the basis is 

 wanting, as Kemp believes, or whether the basis is present and the ischium and 

 merus fused to account for the 6-jointed thoracic legs of stomatopods as compared 

 with the 7-jointed ones of other Malacostraca. 



27 Except in the Mediterranean Pseudosquilla ferussaci (Giesbrecht, Fauna u. 

 Flora d. Golfes v. Neapel, Monog. 33, Stomatopoden, p. 34, pi. 4, figs. 37-48, 1910). 

 Kemp states, "It seems to combine the telson of a Pseudosquilla with many of the 

 characteristic features of Squilla, but is perhaps rather more nearly allied to the 

 former genus than to the latter." 



