Icacinaceae

Rio, Cédric Del, Stull, Gregory W. & Franceschi, Dario De, 2020, Survey of the fruits and endocarps of Icacinaceae (Lamiids, Icacinales), European Journal of Taxonomy 645, pp. 1-130 : 9-10

Key to genera of Icacinaceae s.str.

1. Endocarp wall homogeneous comprised of isodiametric cells .............................. Cassinopsis Sond. – Endocarp wall not homogeneous or cells not exclusively isodiametric ........................................... 2

2. Hairs present on the locule surface ................................................................................................... 3 – Hairs absent from the locule surface ................................................................................................ 4

3. Endocarp width ca 40 mm, endocarp wall more than 700 µm thick ........................ Lavigeria Pierre – Endocarp width ca 13 mm, endocarp wall less than 400 µm thick ................................ Leretia Vell.

4. Locule surface papillate .................................................................................................................... 5 – Locule surface not papillate .............................................................................................................. 6

5. Outer endocarp surface pitted ........................................................................................................... 7 – Outer endocarp surface not pitted ..................................................................................................... 8

6. Hairs-like unit present on the endocarp surface ................................................. Pleurisanthes Baill. – Hairs-like unit absent from the endocarp surface ............................................................................. 9

7. Tubercles bullate ....................................................................................................... Miquelia Meisn. – Tubercles spiny, cylindrical, peg-shaped or elongate-flattened ........................ Pyrenacantha Hook.

8. Endocarp primary vascular bundle embedded within endocarp wall ............................. Iodes Blume – Endocarp primary vascular bundle outside endocarp wall or in a channel .................................... 10

9. Outer endocarp surface pitted ..........................................................................................................11 – Outer endocarp surface not pitted ................................................................................................... 12 10. Outer endocarp surface completely smooth ................................................................... Iodes Blume – Outer endocarp surface ridged or rugose, irregular ........................................................................ 13

11. Pits within shallow mounds slightly protruding inside the locule .......................... Phytocrene Wall. – Pits within tubercles protruding inside the locule ........................................................................... 14

12. Endocarp thickness> 12 mm ..................................................................................... Icacina A.Juss. – Endocarp thickness <10 mm .......................................................................................................... 15

13. Endocarp length ca 12 mm .................................................................. Hosiea Hemsl. & E.H.Wilson – Endocarp length> 15 mm ............................................................................................................... 16

14. Tubercles bullate ................................................................................................. Stachyanthus Engl. – Tubercles spiny, cylindrical, peg-shaped or elongate-flattened ........................ Pyrenacantha Hook.

15. Endocarp ridged and reticulate ....................................................................................................... 17 – Endocarp rugose, irregular .............................................................................................................. 18

16. Endocarp almost smooth, irregularly rugose but without clear protuberant structures ...................... .................................................................................................................. Sarcostigma Wight & Arn. – Endocarp rugose with clear protuberant structures or ridged ......................................................... 19

17. Endocarp oblong .................................................................................... Alsodeiopsis Oliv. in Benth. – Endocarp elliptical .......................................................................................................................... 20

18. Endocarp apex with prominent bulge or pores ............................................................................... 21 – Endocarp apex without ornamentation .......................................................................... Mappia Jacq.

19. Endocarp rugose, irregular ....................................................................... Mappianthus Hand. -Mazz. – Endocarp ridged with a reticulate or diffuse ornamentation ................................ Rhyticaryum Becc.

20. Endocarp length ca 9 mm, 4–5 areoles formed by ridges on each face .............................................. ........................................................................................................... Natsiatum Buch. -Ham. ex Arn.

– Endocarp length> 11 mm, 20–30 areoles formed by ridges on each face .......................................... .................................................................................................... Vadensea Jongkind & O.Lachenaud

21. Endocarp with subapical pores .................................................. Vadensea Jongkind & O.Lachenaud – Endocarp with apical bulge ............................................................................................................ 22

22. Ornamentation bullate, occuring in Madagascar............................. Desmostachys Planch. ex Miers – Ornamentation more granular, occuring in Asia ............................................... Nothapodytes Blume