768 



ARTHROPODA 



PHYLUM VII 



Division D. HOPLOCARIDA Calman. 

 Order 1. STOMATOPODA Latreille.i 



Carapace small, leaving at hast four of the thoracic somües dM and mv 

 covered with a movable rostral plate anteriorly. Eyes pedunculate Eyes ard 

 Znnules hörne on raovahle segments of the head. First fivepans of thoracu hmls 

 ^b.chelaie, the second pair very large. Abdomen largeand depressed, endmg ^n a 

 taü-fan. First five pairs of abdominal appendages carrymg tufted güls. 



The existing Stomatopods form a very homogeneous group, within which 

 onlv one family (Squillidae) can be recognised, while many of the genera are 

 separated by comparatively slight differences. Representative forms are 

 Squüla Y^hr ■ LysiosquiUa ^nd PseudüsquillaB^nii ; Gonodactylus L^treiWe ; ^nd 

 Coronida Brooks. Modern Stomatopods are exclusively marine, the adults 



generally inhabitmg burrows 

 in the sand or mud of the sea- 

 bottom in shallow water, chiefly 

 in the tropics, but extend- 

 ing also 50 degrees on either 

 side of the equator. Many 

 species seem never to wander 

 far from their burrows, into 

 which they retreat with great 

 rapidity when alarmed. The 

 larval stages, on the other 

 band, are exclusively pelagic, 

 of glass-like transparen cy, and 

 occur in great numbers in the 

 plankton of the warmer seas. 

 All the Stomatopods appear 

 to be of active, predatory 

 habits. They ränge in size 

 approximately from 38 to 

 340 mm. 



The existence of Stoma- 

 topods in Paleozoic times is 

 still doubtful. Necroscilla 

 Woodward, from the English Goal Measures, is based on a fragment of the 

 abdomen and telson. Perimecturus Peach, from the Carboniferous of 

 Scotland, shows several features, such as the massiveness of the abdomen and 

 the movable rostral plate, that suggest an affinity with this Order. In the 

 Kimmeridgian of Solenhofen undoubted Stomatopods occur, some of which 

 are even referred to the Recent genus Squilla Fabr. (also known from 



^ Literatiire: Münster, G. Graf zu, Beitrage zur Petrefaktenkunde. Parts iii. and v., 1840- 

 1842. — Mark, W. von der, and Schlüter, 0., Neiie Fische und Krebse aus der Kreide von Westplialen. 

 Palaeontogr., 1868, vol. xv.—Kunth, A., Über wenig bekannte Crustaceen von Solenhofen. 

 Zeitschr. Deutsch. Geol, Ges., 1870, vol. :kx\\.— Woodward, II., Contribntions to the knowledge of 

 fossil Crustacea. Quart. Journ. Geol. Soc, 1879, vol. xxxv.— Brooks, W. A", Report on the 

 Stomatopoda. Scient. Results Challenger Exped., Zool., 1886, vol. xyl—Miers, E. J. On the 

 Squillidae. Ann. Mag. Nat. Hist., 1880, ser. 5, vol. v. 



Fig. 1495. 



ScuMa pennata Münst. Upper Jura ; Bavaria. A, B, Dorsal 

 views, i/i and 3/j. c, Ventral aspect, 3/^. a, e, First and second 

 pairs of antennae (aft«r Kunth). 



