526 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 117 



Palm of gnathopod 2 short, article 7 about half as long as hindmargin of 

 article 6 L. smithi 



14. Article 6 of gnathopod 1 essentially bifid, with large proximal posterior 



tooth L. podoceroides 



Article 6 of gnathopod 1 not bifid 15 



15. Article 2 of gnathopod 2 strongly inflated L. kergueleni 



Article 2 of gnathopod 2 slender, edges subparallel 16 



16. Article 6 of gnathopod 2 slightly chelate and longer than article 5. 



L. gambiense 

 Article 6 of gnathopod 2 not chelate 17 



17. Anterior edge of article 5 of gnathopod 1 densely setose . . . L. websteri 

 Anterior edge of article 5 of gnathopod 1 poorly or not setose 18 



18. Distal anterior corner of article 2 on gnathopod 2 with process 19 



Distal anterior corner of article 2 on gnathopod 2 lacking process .... 20 



19. Defining tooth of gnathopod 1 not set apart from palm . . L. hypacanthiis 

 Defining tooth of gnathopod 1 set apart from palm by excavation. 



L. concavus 



20. Palm of gnathopod 1 distinctly transverse (see notes) 21 



Palm of gnathopod 1 oblique 22 



21. Article 7 of gnathopod 1 with inner bump, ventrum of pereon with 4 large 



and 2 small posteriorly projecting teeth L. audbettius 



Article 7 of gnathopod 1 lacking inner bump, ventrum of pereon with 2 

 anteriorly projecting teeth L. macromanus 



22. Eyes absent, coxae very small 23 



Eyes present, coxae of normal size 24 



23. Pereopod 4 reaching to end of article 4 on pereopod 5 L. lobata 



Pereopod 4 reaching to end of article 5 on pereopod 5 . . L. longidigitans 



24. Gnathopod 2 quite slender, article 6 nearly twice as long as article 5. 



L. leptocheirus 

 Gnathopod 2 not markedly slender, article 6 subequal to article 5 in length. 25 



25. Palm of gnathopod 1 lacking medial process or one near finger hinge, palm 



excavate and with defining tooth 26 



Palm of gnathopod 1 bearing either a medial process or one near finger hinge. 27 



26. Ventrum of pereon garnished with numerous spines . . . . L. spiniventris 

 Ventrum of pereon lacking spines L. viguieri 



27. Article 7 of gnathopod 1 overlapping palm by almost half its length. 



L. aequimanus 

 Article 7 of gnathopod 1 scarcely overlapping palm 28 



28. Medial palmar process of gnathopod 1 formed into a distinct blunt lobe. 



L. fuegiensis 

 Medial palmar process of gnathopod 1 indistinct but sharp . L. intermedius 



Notes. — References to species may be consulted in J. L. Barnard's 

 (1958) Index. Other species described since then: L. audbettius 

 J. L. Barnard (1962a); L. lobata J. L. Barnard (1962d). 



Lembos tetracanthus might be the young of L. francanni. 



L. teleporus K. H. Barnard, 1955: coxa 1 and article 4 of gnatho- 

 pod 2 not described; keys out either to couplets 7, 9, or 25 but is 

 distinguished from those relatives by gnathopod 1 for which the 

 original drawing should be checked. 



