IAWA Jo urnal, Vol. 17 (I), 1996: 45 -75 WOOD ANATOMY OF THE TRIBE SWARTZIEAE WITH COMMENTS ON RELATED PAPILIONOID AND CAESALPINIOID LEGUMINOSAE by Peter Gasson Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3DS, United Kingdom SUMMARY The tribe Swartzieae, like the Sophoreae is a basal member of the Papil­ ionoid legumes, lying at the boundary between this subfamily and the Caesalpinioideae (Polhill & Raven 1981). Recent surveys have investi­ gated the wood anatomy of 42 out of the 48 genera in the Sophoreae (Fujii & Baas 1992; Fujii et al. 1994; Gasson 1994; Den Outer & Van Veenendaal 1992). Similar work is needed on the Swartzieae ( II gen­ era), and in the Caesalpinioideae on Caesalpinieae (47 genera), Am­ herstieae (25 genera) and Detarieae (55 genera). The wood anatomy of Swartzieae is described here, the genus Baphiopsis apparently for the first time, and comparison is made especially with Sophoreae. There is no clear delimitation between the two tribes, which is confirmed by cladistic analysis on 12 wood characters of Swartzieae alone, then com­ bined Swartzieae and Sophoreae. Baphiopsis (Swartzieae) and Baphia (Sophoreae) are so similar anatomically that they should perhaps be in the same tribe, and Bocoa is not uniform anatomically, and may not be a coherent genus. The data presented here will assist in reaching conclu­ sions on the correct delimitation of some genera and tribes in the Papil­ ionoid legumes. Key words: Swartzieae, Baphiopsis, generic wood descriptions. INTRODUCTION The tribe Swartzieae is placed in the Legume subfamily Papilionoideae by Polhill and Raven (198 1), and according to Cowan (1981) consists of II genera (see Table I). With the tribe Sophoreae, which contains 48 genera (Polhill 1981a), it lies at the bound­ ary of the Papilionoideae with the Caesalpinioideae. The phylogenetic relationships of the Swartzieae have been explored by Herende en (1995), including 19 Sophoreae and three genera of Caesalpinieae using flower, fruit, pollen and leaf, but not wood charac­ ters. He found that Swartzieae was polyphyletic and could not support the view that the tribe is basal to the Papilionoids. This paper describes the wood anatomy of at least one species from ten out of the eleven genera recognized as Swartzieae by Cowan (1981). A similar style and format, and identical charac ter states are used as in Gasson Downloaded from Brill.com10/04/2021 07:40:11AM via free access 46 IAWA Journal, Vol. 17 (1),1996 Table 1. Genera in the tribe Swartzieae. A list ofthe genera in the Swartzieae following Polhill (1981), giving coding of characters suitable for cladistic analysis, and for each genus, the number of species, the number examined in this study and whether or not there is an y published information on wood ana tomy. The charac ters are the same as those code d for the Sophoreae (Gasson 1994) . 2 2 3 4 5 6 7 8 9 10 I I 12 13 14 15 Aldina 0 0 0 0 0 0 I 0 0 1 I 0 15 1 Y Swartzia (Neotropical) 0 0 0 0 0 0 011 0 I I 011 o 133 19 Y Swartzia (African) 0 0 0 0 0 0 011 0 0 1 1 0 2 2 Y Bocoa alterna 0 0 0 0 0 0 011 0 I 0 0 0 1 1 Y Bocoa prouacensis / viridiflo ra 0 0 0 0 0 0 011 0 011 II 0 6 2 Y Lecointea 0 0 0 0 0 0 1 0 0 1 1 0 4 I Y Candolleodendron 0 0 0 0 0 0 011 0 011 1 011 0 1 I Y Harleyodendron 0 0 0 0 0 0 I 0 0 I 0/1 I I 1 Y Exostyles ???????? ???? 2 0 N Zollernia 0 0 0 0 0 0 011 0 011 I 011 I 12 3 Y Cordyla 0 0 0 0 0 0 1 0 0 0/1 011 0 5 I Y Mildbraediodendron 0 0 0 0 0 0 I 0 0 I I 0 1 1 Y Baphiopsis 0 0 0 0 0 0 1 0 011 1 011 0 I I N Table 1 continued: Wood anatomical characters of Sophoreae and Swartzieae. 1. Porosity and Growth rings: 8. Rays not of two distinct sizes 0 Diffuse-porou s without growth rings 0 Rays of two distinct sizes I Diffuse-porous with growth rings I 9. Rays homocellul ar 0 Ring-porous 2 Rays heterocellular 1 2. Vessels of one diameter class 0 10. Axial parenchyma not storied 0 Vessels of two distinct diameters 1 Axial parenchyma storied I Axial parenchym a irregularly storied 011 3. Vessels not in dendritic arrangement 0 Vessels in dendritic arrangement 1 II. Rays not storied 0 Rays storied 1 4. Vessels without spiral thickenings 0 Rays irregularly storied 011 Vessels with spiral thickenings 1 12. Crystals not seen in ray cells 0 Vascular tracheids absent 0 5. Crystals present in ray cells 1 Vascular tracheids present 1 6. Fibres non-septate 0 13. Number of species in genus Fibres septate 1 14. Number of species examined in this study 7. Axial parenchyma : IS. Published information on wood Scanty paratracheal and/or vasicentric 0 anatomy exists y Aliform I confluent I unilateral para- No published information on wood tracheal I banded I anatomy found N Downloaded from Brill.com10/04/2021 07:40:11AM via free access Gasson - Wood anatomy of the Swartzieae, Leguminosae 47 (1994) on Sophoreae, although in this paper each genus is treated individually, whereas in the Sophoreae paper the groups ofgenera recognized by Polhill (1981a) were used as the basis for descriptions. There is published information on the wood anatomy of nine of the eleven genera. Only Baphiopsis and Exostyles are not covered in the literature. This paper describes the wood of the former for the first time, but no material of the latter could be obtained from the most likely Brazilian sources. The wood anatomy of South American Swartzieae is almost comprehensively covered by Detienne and Ter Welle (1989) in the Caesalpiniaceae issue of Flora of the Guianas, which includes the genera Aldina, Bocoa, Candolleodendron, Lecointea, Swartzia and Zollernia. The Brazilian tree Harleyodendron from the Atlantic rain forest is described by Bedell in Cowan (1979) . Other relevant publications are given with each genus account. GENERAL WOOD DESCRIPTION Wood diffuse-porous. Vessels solitary, in pairs, some short radial multiples and clus­ ters, but in no predominant pattern. Vessel elements relatively short, with alternate, usually fine, vestured intervascular pits and simple perforation plates. Vessel-ray pit­ ting similar to intervascular pitting in size and shape, half-bordered. Fibres non-septate with slit-like, apparently simple pits. Axial parenchyma scanty paratracheal to vasi­ centric, aliform and confluent, and sometimes with bands of varying width , usually storied. Rays generally no wider than 5 cells, mainly homocellular, consisting mostly of procumbent cells, non-storied, irregularly-storied or storied depending on genus and species. Prismatic crystals in chambered axial parenchyma cells present in most species, also present in ray cells in a few species. GENERIC WOOD DESCRIPTIONS AND PREVIOUS LITERATURE Aldina - Fig. 1-4 About 15 species from the neotropics. The wood has been described by Dechamps (1980, A. insignis), Detienne & Jacquet (1983, A. aff. latifolia) and Detienne & Ter Welle (1989, A. insignis & A. latifolia) . The description here is based on one species, A. insignis. Vessels often in short radial multiples, some solitary. Fibres thick-walled, with vir­ tually no lumen . Axial parenchyma very abundant, aliform and confluent, in higher proportion than fibres. Axial parenchyma in strands of 2-4 cells, storied. Rays 1-4 cells wide and up to about 16 cells high, storied, homocellular, consisting entirely of procumbent cells. [Detienne & Ter Welle's description of A. insignis and A. latifolia recognises " 1 marginal row of weakly procumbent or square cells" (sic) and the fibres in A. latifolia (their Fig. 1.1) are in higher proportion in transverse section when compared with Figures 1 and 2 here of A. insignis.] Downloaded from Brill.com10/04/2021 07:40:11AM via free access 48 IAWA Journ al, Vol. 17 ( 1), 1996 Baphiopsis parvijlora - Fig. 5-9 Baphiopsis is monotypi c from the forests of tropical Africa. The wood appears not to have been described previously, and the voucher speci men in the Kew Herbarium, shown in Figure 5, is the holotype. Vessels narrow and relatively sparse, solitary and in small clusters of up to 4 or 5. Fibres thick-walled with little or no lumen. Axial parenchym a aliform to confluent, in lower proportion than the fibres. Axial parenchyma strands mainly 2-celled, but some fusiform, storied. Rays 1-4 cells wide and up to at least 30 cells high, low rays storied and the same height as one axial parenchyma storey, higher rays up to two axial paren­ chyma storeys. Co mpos ition of rays variable, many homocellular with entirely procumbent cells. Bocoa - Fig. 10-1 9 Seven species from the neotropic s, three described here: Bocoa alterna, B. proua­ censis and B. viridijlora. The most detailed account of the wood anatomy is by De­ tienne & Ter Welle (1989 , same three species as here), with other papers by Benoist (1931), Detienne et al. (1982, B.prouacensis) and Detienne & Jacquet (1983, B. proua­ censis). The genus is not uniform in its wood anatomy. Bocoa aiterna (Fig. 10-1 4) has abunda nt vesse ls in radial multiples up to at least 9, parenchyma that is sca nty paratracheal, in discontinuous bands up to 3 cells wide and irregularly-storied, non­ storied heterocellul ar rays that are I or 2 cells wide and up to about 40 cells high, and there are abundant prismatic crystals in ray cells in some samples.