MARINE FLORA AND FAUNA OF THE 



NORTHEASTERN UNITED STATES. 



Crustacea: Stomatopoda 



RAYMOND B. MANNING' 



ABSTRACT 



This manual includes an introduction on the general biology, an illustrated key, an annotated 

 systematic list, a selected bibliography, and an index to the stomatopod Crustacea of the inner continental 

 shelf of the Northeastern United States. Four species are treated. 



INTRODUCTION 



The crustacean order Stomatopoda is a small 

 group of primitive crustaceans found almost exclu- 

 sively in shallow tropical waters. More than 300 

 species in four families are known. Although 70 

 species have been recognized in the western Atlan- 

 tic, only four are found in the Northeastern United 

 States. Two of these. Nannosquilla f>ruyi (Chace) 

 and Sqiiilla empiisa Say. live in shallow water, 

 whereas the other two, Heterosqiiilhi ainiatci 

 (Smith) and Platysquilla enodis (Manning), live in 

 depths of 30 m or more. All four species are included 

 in the key given below. 



The stomatopods or mantis shrimps can be recog- 

 nized by the presence of two anterior movable so- 

 mites bearing eyes and triramous antennules, a 

 carapace which covers the anterior portion of the 

 cephalothorax dorsally but leaves the four posterior 

 thoracic somites (No. 5-8) free, five pairs of subc he- 

 late thoracic appendages (one of which is greatly 

 enlarged as a raptorial claw), and abdominal gills 

 (Fig. 1). The common name of these organisms, 

 mantis shrimps, alludes to the resemblance of the 

 raptorial claws to those of the praying mantis (Fig. 

 2). 



Adult stomatopods are primarily benthic or- 

 ganisms that usually live in burrows. So far as is 



' National Museum of Natural History. Smithsonian Institu- 

 tion, Washington, D.C, 20560. 



known, all species are predators, and some leave 

 their burrows at night to feed. The female canies the 

 oval egg mass between her maxillipeds until the 

 young hatch. 



The planktonic larvae, known as alima or 

 erichthus larvae, go through a number of distinct 

 stages before settling on the botton; each species 

 may have as many as 10 separate larval stages. The 

 larvae of most species are unknown. 



Our knowledge of most aspects of the general 

 biology of stomatopods and their interrelationships 

 with other organisms at best can be characterized as 

 scanty. Often our knowledge is restricted to the ex- 

 ternal morphology of a few individuals of a species. 

 For example, many of the specimens of the two 

 species, Heterosqiiilla annata and Platysquilla 

 enodis, known from deeper waters off the North- 

 eastern United States were found in stomach con- 

 tents of fishes, and this is practically ail that we know 

 about these species ;F. enodis is known from parts of 

 three specimens. In contrast, specimens of the other 

 two species, Nannosquilla ,^rayi and Squilla em- 

 piisa. living off the Northeastern United States are 

 comparatively common. Judging from collections 

 made by M. B. Gray in the 1950"s, Nannosquilla 

 i>rayi was abundant in the Bass River, Yarmouth, 

 Cape Cod, and material might be collected readily 

 for a variety of studies. Similarly, Squilla empusa. 

 which seems to be abundant throughout its range, 

 could serve as the subject for many investigations. 



