Rhachotropis S. I. Smith 1883
Creators: name: Bellan-Santini, Denise
Publisher: name: Zenodo
Year: 2006
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Eusiridae
Rhachotropis

description: Key to Atlantic Rhachotropis   
1. Telson entire.................... 2  
– Telson cleft or emarginate................ 4  
 2. Eyes present................ R. integricauda   
– Eyes absent..................... 3  
 3. Pleon, segments 1 and 2 with dorsal tooth only........ R. caeca   
 – Pleon, segments 1 and 2 with lateral tooth only..... R. flamina n. sp.   
4. Rostrum long or medium................. 5  
– Rostrum short................... 14  
5. Eyes present.................... 6  
– Eyes absent.................... 10  
6. Telson emarginated.................. 7  
– Telson cleft..................... 8  
 7. Pereon, segment 7 and pleon segments 1-3 with median dorsal tooth. R. proxima   
 – Pereon, segment 7 and pleon segments 1-3 smooth smooth..... R. glabra   
8. Epimeral, plate 3 hardly denticulate.............. 9  
 – Epimeral, plate 3 not hardly denticulate......... R. inermis   
 9. Pereon, segments 6-7 with acute dorsal processes....... R. aculeata   
 – Pereon, segment 6 smooth, segment 7 with a posterodorsal mucronation R. oculata   
10. Epimeral, plate 3 hardly denticulate............. 11  
 – Epimeral, plate 3 weakly denticulate............ 12 11. Pleon, segments 1-2 armed............. R. rostrata   
 – Pleon, segments 1-2 not armed........... R. pilosa n. sp.   
 12. Pleon, segment 1 with one dorsal and two lateral teeth..... R. proxima   
– Pleon, segment 1 smooth................ 13  
 13. P7 basis lobate, ‘‘accessory flagellum could not be found’’.... R. faeroensis   
 – P7 basis not lobate, accessory flagellum present but minute.... R. distincta   
 14. A1, article 1 with a terminal spine......... R. licornia n. sp.   
– A1, article 1 without terminal spine............. 15  
15. Eyes present................... 16  
– Eyes absent.................... 21  
 16. Eyes yellowish white............. R. leucophthalma   
– Eyes not white................... 17  
 17. Eyes reduced in size.............. R. lomonosovi   
– Eyes large.................... 18  
 18. Pleon, segment 3, dorsally rounded without tooth....... R. inflate   
– Pleon segment 3 with dorsal tooth............. 19  
 19. Pereon, segments 1-3 ‘‘raised dorsally’’ (Sars dixit)....... R. helleri   
– Pereon, segments 1-3 not (raised dorsally)........... 20  
 20. Urosome, segment 1 smooth............. R. grimaldii   
 – Urosome, segment 1 with a tooth........... R. macropus   
 21. P5-7 basis expanded in an acute projection........ R. palporum   
– P5-7 basis not expanded in an acute projection......... 22  
22. Telson cleft for one-third length.............. 23  
– Telson emarginate.................. 24  
 23. Urosome, segment 1 weakly carinate. Coxa 1 strongly produced.. R. thordisae   
 – Urosome, segment 1 without carina. Coxa 1 weakly produced.... R. gislii   
 24. Urosome, segment 1 without tooth.......... R. portoricana   
– Urosome, segment 1 with dorsal tooth............ 25  
 25. Pleon, segments 1-2 weakly tridentate dorsally....... R. thorkelli   
 – Pleon, segments 1-2 slightly humped with low dorsal tooth..... R. arii
description: Published as part of Bellan-Santini, Denise, 2006, Rhachotropis species (Crustacea: Amphipoda: Eusiridae) of hydrothermal vents and surroundings on the Mid- Atlantic Ridge, Azores Triple Junction zone, pp. 1407-1424 in Journal of Natural History 40 (23 - 24) on pages 1422-1423, DOI: 10.1080/00222930600956809, http://zenodo.org/record/5228418