Botanical Journal of the Linnean Society, 2010, 164, 16–25. With 3 figures

Petenaeaceae, a new angiosperm in with a distant relationship to

Gerrardina (Gerrardinaceae)boj_1074 16..25

1,2 3

MAARTEN J. M. CHRISTENHUSZ * FLS, MICHAEL F. FAY FLS, Downloaded from https://academic.oup.com/botlinnean/article/164/1/16/2418579 by guest on 01 October 2021 JAMES J. CLARKSON3, PETER GASSON3 FLS, JULIO MORALES CAN4, JORGE B. JIMÉNEZ BARRIOS4 and MARK W. CHASE3 FLS

1Botanic Garden and Herbarium, Finnish Museum of Natural History, PL7 (Unioninkatu 44), University of Helsinki, 00014 Helsinki, Finland 2Department of Botany, Natural History Museum, Cromwell Road, London, SW7 5BD, UK 3Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, UK 4Herbario, Centro de Estudios Conservacionistas (CECON), Universidad de San Carlos de Guatemala, Avenida La Reforma 0-63, zona 10, 01010 Guatemala Ciudad, Guatemala

Received 23 April 2010; revised 21 July 2010; accepted for publication 22 July 2010

Petenaea cordata (from northern Central America) was first described in Elaeocarpaceae and later placed in Tiliaceae, but most authors have been uncertain about its familial affinities. It was considered a taxon incertae sedis in the Angiosperm Phylogeny Group classification (APG III). A recent collection was made in Guatemala, and analysis of both rbcL and atpB in the large Soltis et al. angiosperm matrix, the most completely sampled study published to date, indicated a moderately supported relationship to (, the only member of the newly recognized Huerteales in this matrix; 81% bootstrap support). We then conducted a more restricted analysis using the Bayer et al. rbcL/atpB matrix for supplemented with the other genera of Huerteales from published studies. Our results indicate a distant, weakly supported sister-group relationship to the African (Gerrardinaceae; Huerteales). After comparison of the characters cited in the literature and an examination of herbarium material of both genera, we could find no obvious synapomorphies for Gerrardina and Petenaea or any other relationship of the latter, and we therefore propose the new monogeneric family, Petenae- aceae. The polymorphic order Huerteales now comprises four small families: , Gerrardinaceae, Petenaeaceae and Tapisciaceae. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164, 16–25.

ADDITIONAL KEYWORDS: APG III – atpB – Belize – Elaeocarpaceae – Guatemala – Malvales – Malvanae – Mesoamerica – Mexico – Muntingiaceae – Petenaea – rbcL – Tiliaceae – wood anatomy.

INTRODUCTION reminiscent of Tilia L. with large palmately veined, cordate , red petioles and unusual apetalous Petenaea cordata Lundell (Fig. 1) occurs in a small flowers with conspicuously long, coarse pink hairs. region of northern Central America, with scattered Petenaea was described in 1962, as a new genus of localities in the states of Chiapas and Tabasco in Elaeocarpaceae (Lundell, 1962), as its wood anatomy is Mexico, the states of Huehuetenango, Alta Verapaz similar to that of members of that family (Kukachka, and Petén in Guatemala and in Belize. It can be found 1962). Petenaea was later considered to be a member of in seasonally dry to wet tropical forests, often in Tiliaceae (Mabberley, 1997), probably because of a somewhat open habitats, such as lake shores and superficial resemblance to members of that family. The roadsides. It is a handsome that is somewhat genus was difficult to place because of its unusual combination of characters: simple and branched tri- *Corresponding author. E-mail: [email protected] chomes, palmate/cordate leaves with tiny stipules,

16 © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164, 16–25 THE NEW FAMILY PETENAEACEAE 17 Downloaded from https://academic.oup.com/botlinnean/article/164/1/16/2418579 by guest on 01 October 2021

Figure 1. Petenaea cordata in Huehuetenango, Guatemala. A, Flower close-up. B, Habit. C, Branch with leaves and inflorescence. Photographs by Maria Vorontsova.

© 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164, 16–25 18 M. J. M. CHRISTENHUSZ ET AL. replaced by (but not homologous with) monili- yielded only an amplification product for rbcL. Mate- form hairs, receptacular glands between the anthers, rial collected by the first author on 14 March 2009 in dorsifixed anthers that dehisce through a terminal slit the state of Huehuetenango, community Nentón, in that eventually opens down the full length of the cloud forest along the road from Nuevo San José anther and a large axile placenta with numerous Frontera to Las Palmas (16°2′N, 91°33′W) at an and berry-like fruits (Bayer, 2003). The pres- elevation of c. 1000 m (Christenhusz 5616, BM, H, ence of minute stipules and a somewhat similar MO, USCG), was dried in the field in silica gel (Chase structure led Lundell (1962) to suggest that Petenaea & Hills, 1991). DNA was extracted from 0.20–0.25 g of could be related to Muntingia and Dicraspidia (later silica-dried leaves using the 2 ¥ cetyltrimethylammo- described as Muntingiaceae; Bayer, Chase & Fay, nium bromide (CTAB) method of Doyle & Doyle

1998), but the lack of petals in Petenaea and the (1987). The sample was purified on a caesium Downloaded from https://academic.oup.com/botlinnean/article/164/1/16/2418579 by guest on 01 October 2021 differences in wood anatomy between the two (Gasson, chloride/ethidium bromide gradient (1.55 g mL-1 1998) made this relationship appear unlikely. The density). Amplification of rbcL was carried out as absence of vestured pits in the wood of Petenaea also described in Fay, Swensen & Chase (1997). The weakens a putative relationship with core Malvales amplified products were purified using the QIAquick (Jansen, Baas & Smets, 2000). PCR Purification Kit (Qiagen, Crawley, West Sussex, In the analysis of Bayer et al. (1999), based on rbcL UK). Cycle sequencing was carried out using a Big and atpB sequences for Malvales, Petenaea (with just Dye Terminator v 3.1 Cycle Sequencing Kit (Applied an rbcL sequence) was sister to Dicraspidia Standl. Biosystems, Inc., ABI, Warrington, Cheshire, UK) and Muntingia L. (Muntingiaceae), but with < 50% with the same primers as used for PCR amplification, bootstrap support. Although this analysis also following the protocols provided by the manufacturer. included members of and , Both strands were sequenced. The other gene used in members of Huerteales were absent, and so sampling the Bayer et al. (1999) analysis was plastid atpB, and of members of Malvanae Chase & Reveal (the this was amplified using the primers of Hoot, Culham malvid clade; Chase & Reveal, 2009) was incomplete. & Crane (1995). We also amplified and sequenced the In APG II (2003), Petenaea was tentatively placed in trnL intron and trnL-F intergenic spacer using the c Muntingiaceae, but there were no obvious characters and f primers of Taberlet et al. (1991) because this supporting this relationship, except perhaps for the locus was used in Worberg et al. (2009) as a secondary ovary condition. In APG III (2009), Petenaea was dataset. GenBank accession numbers for Petenaea considered to be a taxon incertae sedis. cordata used in this study are: FN677367 (rbcL), During an expedition to Huehuetenango in Guate- FN677366 (atpB) and FR666771 (trnL intron/trnL-F mala, we encountered a population of Petenaea spacer). We also considered evaluating the position of cordata (Fig. 1). Access to this new collection allowed Petenaea in the large matK data matrix of Hilu et al. us to reassess the placement of this genus, one of the (2003), but the sampling in superorder Malvanae in few remaining unplaced genera in the angiosperms this paper was much more restricted than in Soltis (APG III, 2009). In order to place Petenaea,wemade et al. (2000) and did not include any members of use of the large Soltis et al. (2000) matrix and subse- Huerteales. Of course, it would have been possible to quently used a reduced matrix from Bayer et al. add the matK sequences from the study of Worberg (1999) because it fell with Tapiscia Oliv. (Tapisci- et al. (2009) to the Hilu et al. matrix, but, by adding aceae, in the recently recognized order Huerteales; numerous additional sequences, the matrix loses com- Worberg et al., 2009) in the broader analysis; we parability with the published Hilu et al. study, and supplemented the latter matrix with sequences for all then necessitates a much more extensive analysis and members of Huerteales (downloaded from GenBank) more detailed reporting of the results, which we felt [Gerrardina Oliv. (Gerrardinaceae), Kunth was beyond the scope of this study. We therefore did and Dunn (Dipentodontaceae) and not produce a trnK/matK sequence for Petenaea. Ruiz & Pav. and Tapiscia (Tapisciaceae)] to Members of Sapindales were assigned as the ultimate evaluate its placement among the orders Brassicales, outgroup based on the results of Worberg et al. Huerteales, Malvales and Sapindales. (2009). We used the parsimony algorithm of the software package PAUP 4.0b10 for Macintosh (Swofford, 2003). MATERIAL AND METHODS A tree search was conducted under the Fitch (equal Material from Petenaea has only been included pre- weights) criterion (Fitch, 1971) with 1000 random viously in one molecular study (Bayer et al., 1999). sequence additions and TBR (tree bisection– The herbarium sample Pennington & MacQueen reconnection) branch swapping, but permitting only 13427 (K) from Petén, Guatemala, was used for that two to be held at each step. A quick bootstrap analysis and, because of its degraded condition, procedure using subtree-pruning–regrafting (SPR)

© 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164, 16–25 THE NEW FAMILY PETENAEACEAE 19 swapping and 100 replicates with simple addition was were found, tree length 2649 steps, with a consis- conducted to determine internal support (a procedure tency index of 0.48 and a retention index of 0.64. that could only underestimate support). On the basis One of these eight, that agreeing with the Bayesian of these results (not shown), which placed Petenaea analysis (see below), is illustrated in Fig. 2, showing with Tapiscia (with 81% bootstrap support), we modi- both the bootstrap percentages (BPs) and PPs below fied the Bayer et al. (1999) rbcL/atpB matrix by the branches and branch lengths (DELTRAN opti- reducing the number of taxa from Malvaceae s.l. and mization) above the branches. The results for the adding sequences from GenBank (Alford, 2006; Zhang non-Huerteales taxa are identical with those & Simmons, 2006) for the remaining members of obtained by Bayer et al. (1999), which are not Huerteales, plus the rbcL and atpB sequences of described or discussed here. Huerteales are mono-

Petenaea produced for this study. We used the same phyletic (60 BP; Fig. 2) and sister to Brassicales (60 Downloaded from https://academic.oup.com/botlinnean/article/164/1/16/2418579 by guest on 01 October 2021 methods as specified above, but saved ten trees per BP). Within Huerteales, there are two major sub- replicate with TBR swapping on the modified Bayer clades, one formed by Gerrardina (Gerrardinaceae) et al. (1999) matrix. For these taxa, all trees collected and Petenaea (73 BP), and the other (97 BP) in the 1000 replicates were swapped on to completion. comprising the other four genera of Huerteales, Per- Internal support was evaluated with 1000 replicates rottetia and Dipentodon (both Dipentodontaceae; of bootstrapping (Felsenstein, 1985) with the same 61 BP) and Huertea and Tapsicia (both Tapis- settings as for the heuristic analysis of this matrix. ciaceae; 55 BP). All nodes are weakly supported, MrBayes version 3.1.2 (Huelsenbeck & Ronquist, except for that of Dipentodontaceae/Tapisciaceae (97 2001) was used to analyse the modified Bayer et al. BP). (1999) matrix. An HKY85 model, in which all transi- The results of the Bayesian analysis are identical in tions and transversions have potentially different topology to one of the most parsimonious trees found rates, was specified for the Bayesian analyses. Analy- (Fig. 2). PPs are indicated on the single parsimony ses were performed with 500 000 generations of tree. Support is much higher than produced by par- Monte Carlo Markov chains with equal rates and a simony bootstrapping. Huerteales is strongly sup- sampling frequency of 10. Three separate runs were ported as monophyletic (1.0 PP) and sister to performed to ensure that the analysis was producing Brassicales (1.0 PP); the two major subclades are both consistent results. Microsoft Excel was used to plot well supported (1.0 PP), as is the sister relationship of the generation number against ln L to find the ‘burn Petenaea to Gerrardina (1.0 PP). We note that one in’. These trees of low posterior probability (PP) were node not present in the strict consensus tree, Rho- deleted, and all remaining trees were imported into palocarpus sister to Thymelaeaceae, is strongly sup- PAUP v.4.0b. A majority rule consensus tree was ported in the Bayesian analysis (0.98 PP). Adding produced showing the frequencies of all observed trnL-F sequences for all genera of Huerteales to this bipartitions (i.e. PPs). matrix (with question marks for the outgroups) Three wood samples were sectioned and compared: resulted in a negligible change in overall support, so Gerrardina foliosa Oliv., stem 3 mm in diameter we do not show the results of this analysis. With the excluding bark, South Africa, Rudatis 384 (BM), col- trnL-F region data included, support for Huerteales lected 27.xii.1908; Gerrardina eylesiana Milne-Redh., increased to 70 BP and for Petenaea sister to Gerrar- stem 5 mm in diameter excluding bark, Nyasaland dina to 71 BP. (Malawi), Brass 16441 (BM), collected 26.vi.1946; Petenaea cordata, Guatemala, Pennington & Mac- queen 13427 (K). The sample of Petenaea was from much more mature wood than the samples of Gerrar- WOOD ANATOMY (FIG.3) dina, but the stem diameter was not available. Sec- Gerrardina foliosa (stem 3 mm in diameter tions were cut at around 20–25 mm in transverse (TS), excluding bark) tangential longitudinal (TLS) and radial longitudinal Transverse section: Diffuse porous. Vessels narrow and (RLS) planes, stained with 1% safranin in 50% angular in outline, almost entirely solitary, the only ethanol, 1% aqueous alcian blue, dehydrated through pairs being where one vessel element adjoins another an alcohol series, cleared in histoclear and mounted so that the edge of the perforation plate is present. in euparal. Fibre walls considerably thicker than vessel walls, their single wall thickness greater than the lumen diameter, lumen always present. Axial parenchyma RESULTS rare, scanty paratracheal where present, but only one MOLECULAR or two cells adjacent to any vessel. Rays narrow, one, In the parsimony analysis of the combined matrix, occasionally two cells wide, ray cells much thinner eight most parsimonious trees (all on one island) walled than fibres.

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Figure 2. One of the most parsimonious trees, agreeing with the Bayesian analysis, showing the placement of Petenaea in the Huerteales. Bootstrap percentages and posterior probabilities are shown below the branches; branch lengths are given above the branches.

Longitudinal sections (TLS and RLS): Vessels narrow Gerrardina eylesiana (stem 5 mm in diameter with hardly any intervessel pitting, which is scalari- excluding bark) form if present. Perforation plates scalariform with The wood anatomy is similar to the previous , 13–30 bars. Fibres with conspicuous bordered pits in but a few septate fibres and some tracheids are tangential walls (i.e. these are fibre-tracheids). present, and the rays are slightly wider. Rays one- to two-seriate, from seven to at least 42 cells high, occasionally much wider rays at knots, strongly heterocellular and composed of square and upright Transverse section: Diffuse porous. Vessels solitary, cells. narrow, angular in outline and much more thinly

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Figure 3. Wood anatomy of Petenaea and Gerrardina. Top row : Petenaea cordata, Guatemala, Pennington & MacQueen 13427 (K). Middle row: Gerrardina foliosa, South Africa (Natal), Rudatis 384 (BM). Bottom row: Gerrardina eylesiana, Malawi (Nyasaland), Brass 16441 (BM). Scales indicated in each view; left column, transverse section; middle column, tangential longitudinal section; right column, radial longitudinal section.

© 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164, 16–25 22 M. J. M. CHRISTENHUSZ ET AL. walled than fibres. Fibre walls thick, single wall morphological characters. Their members were not thickness greater than the lumen diameter, bordered known to be related to each other, because they share pits in both radial and tangential walls, but more few obvious synapomorphies (e.g. alternate leaves, apparent in tangential walls in longitudinal section. dentate margins, scalariform perforation plates, Axial parenchyma rare, scanty paratracheal where cauline stipules, cymose inflorescences, usually present. Rays one to three cells wide, much thinner baccate fruits and copious endosperm; Stevens, 2010), walled than fibres. and were thus included in a variety of unrelated families [e.g. (Dipentodon, Perrottetia), Longitudinal sections (TLS and RLS): Intervessel (Gerrardina) and pitting scalariform and opposite where present. Per- (Huertea, Tapiscia)]. They have only been recognized foration plates scalariform with eight to 17 bars.

recently as a putative APG order (Worberg et al., Downloaded from https://academic.oup.com/botlinnean/article/164/1/16/2418579 by guest on 01 October 2021 Tracheids occasional, slightly wider than fibres with 2009), and APG III (2009) recognized them as such. two rows of alternate bordered pits (not seen in G. These genera all have scalariform perforation plates foliosa). Fibres with conspicuous bordered pits, espe- and cymose inflorescences, and so with the addition of cially in tangential walls. Rays one- to three-seriate, Petenaea (simple perforation plates, paniculate inflo- two to at least 42 cells high, some much wider rays at rescences) we lose two putative synapomorphies for knots. Rays strongly heterocellular, composed of the order. The wood of Petenaea is also unlike that of square and upright cells. Vessel ray pitting with any of the other genera of Huerteales (as reviewed in reduced borders, scalariform (no vessel ray pitting Worberg et al., 2009), which are otherwise similar to was found in G. foliosa, but it should be the same). each other. Because the genera of Huerteales share so few characters, they are now placed in four families: Petenaea cordata (a much wider branch or stem) Dipentodontaceae (two genera: Dipentodon, Perrot- Transverse section: Diffuse porous. Vessels mostly in tetia), Tapisciaceae (two genera: Huertea, Tapiscia), radial multiples, two to six. Fibre walls thick, but Gerrardinaceae (monogeneric) and Petenaea (Alford, lumina usually considerably wider than the wall. 2006; Worberg et al., 2009; this study). The lack of Axial parenchyma rare or absent. Rays one to five clear support for a relationship of Petenaea prevents cells wide. us from making a strong argument for its exact place- Longitudinal sections (TLS and RLS): Intervessel ment, although a relationship to Huerteales is the pitting alternate. Perforation plates simple. Fibres best working hypothesis. Nevertheless, there is septate. Axial parenchyma rare or absent (this is strong evidence in the results presented here that it often the case in woods with septate fibres). Rays one is not a member of any of the other orders of super- to five cells wide and up to 40 cells high, strongly order Malvanae (sensu Chase & Reveal, 2009). The heterocellular with many square and upright cells, addition of trnK/matK (Worberg et al., 2009) may but body cells are often procumbent. Vessel ray eventually yield better support for its placement pitting with reduced borders, of various shapes and within Huerteales. sizes, often scalariform. Dipentodontaceae can be identified by the pseudo- umbellate inflorescences, long-exserted and The major differences between the two genera are that simple leaves. Dipentodon has a capsular fruit, Gerrardina has solitary vessels with scalariform per- whereas Perrottetia has berries, like all other foration plates, thick-walled fibre-tracheids and rays Huerteales. Tapisciaceae differ in having imparipin- up to two, occasionally three, cells wide, and Petenaea nate or trifoliate leaves with glands or stipels at the has vessels in radial multiples, simple perforation articulation joint and minute flowers in spicate plates, septate fibres and wider rays. The wood of cymes. Gerrardinaceae are peculiar in having gland- Petenaea is anatomically similar to that of members of tipped leaf denticulations and flowers in axillary Elaeocarpaceae, but is distinguished by all fibres being cymes, and Petenaea is remarkable in its apetalous conspicuously septate. In general, the growth rings are flowers with bright pink trichomes and cordate absent, vessels are solitary, in pairs and radial mul- leaves. tiples up to c. seven. Intervessel pitting is small, The phytogeographical relationships are also per- alternate. Sapwood is thin, heartwood is pale reddish- plexing: Petenaea occurs in a small area in northern brown, bark is thin and not fibrous and pith is small, Mesoamerica, and Gerrardinaceae are found only in round and brown (Kukachka, 1962; Gasson, 1996). fragmented populations in south eastern and south- ern Africa. Tapisciaceae and Dipentodontaceae have similar distributions in China, Southeast Asia to DISCUSSION New Guinea, the Solomon Islands and Queensland, Huerteales are an assemblage of genera that were and in the Neotropics from Mexico to northern Peru previously difficult to place on the basis of their and on some of the Caribbean Islands. These distri-

© 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164, 16–25 THE NEW FAMILY PETENAEACEAE 23

Table 1. Differences between Petenaea and Gerrardina

Petenaea Gerrardina

Venation Palmate Pinnate Leaf margins Dentate Glandular serrate Wood Simple perforation plates Scalariform perforation plates Inflorescence Paniculate Cymose 4 (or 5) 5 Petals 0 5 Stamens 8–12 5, opposite petals Disc Annular Cupular Downloaded from https://academic.oup.com/botlinnean/article/164/1/16/2418579 by guest on 01 October 2021 Ovary Superior with 4–5 carpels Subinferior with 2 carpels Fruit Berry with many seeds Berry with 1–4 seeds Distribution Mesoamerica Africa

butions appear to be relictual; the genera are not only shared characters are unremarkable and wide- closely related and probably used to be more widely spread in the angiosperms. The genera are distinc- distributed in the past than at present. In support of tive, but a single family composed of this set of this hypothesis, Tapiscia has fossils in western genera would be difficult to characterize in a way North America and western Europe (Manchester, that distinguishes them from many others. Their 1988). No fossils of the other taxa have been obvious lack of shared distinctive characters was recorded. responsible for their being one of the last orders to be recognized in the APG classification. Overall, the lack of a clear placement can also be taken as TAXONOMIC OPTIONS support for placement in its own family; as stated The phylogenetic position of Petenaea leads us to above, Chase et al. (2000) noted that nearly all consider four options: (1) no assignment to a family; angiosperm families were found to be strongly sup- (2) inclusion with Gerrardina in Gerrardinaceae; ported with just rbcL data (here we produced data (3) description of a new monogeneric family; or from four regions), and so it seems clear that, (4) expansion of Tapisciaceae to include all genera of regardless of its ultimate position, it is a distant Huerteales, including Petenaea. Support for an relative of any other genus or group of genera. exclusive relationship with Gerrardina is weak (in Despite disliking taxonomic schemes with such contrast, nearly all families were found to be mono- high levels of redundancy, in this case we advocate phyletic with just rbcL data; Chase, Fay & Savol- the recognition of a family for Petenaea and describe ainen, 2000), and so it seems premature and unwise Petenaeaceae (below). From an evolutionary perspec- to place Petenaea in Gerrardinaceae. We have tive, it seems clear that these highly divergent taxa included Table 1 to demonstrate that it shares no without any close relatives are relics of what perhaps obvious characters with Gerrardina, and compari- were once more species-rich and widespread groups; sons with the other genera of Huerteales (Worberg such a scenario is also supported by their biogeogra- et al., 2009) demonstrate equal heterogeneity. In phy, which does not suggest any particular well- addition to their vegetative and floral differences, characterized pattern. Gerrardina and Petenaea also differ in their wood anatomy (that for Gerrardina is reported here for the first time). We are loath to describe a new family In Table 1, we provide an overview of the characters composed of a single species, but the lack of simi- defining Gerrardina and compare these with Pete- larities seems to us a parallel situation to that naea. We find insufficient synapomorphies between observed for Berberidopsidaceae and Aextoxicaceae the two genera (see Table 1), and therefore describe a (). Aextoxicon (monospecific) is dis- new family for Petenaea. tantly related to Berberidopsis (two species) and Streptothamnus (monospecific); they are so different that most authors prefer to place them in separate PETENAEACEAE CHRISTENH., M.F.FAY & families (APG III, 2009). The recognition of a single M.W.CHASE, FAM. NOV. family for all the genera of Huerteales also suffers Frutices vel arbores parvae, trichomatibus multicel- from a similar lack of obvious synapomorphies; the luraribus simplicibus vel ramosis hirsutae. Folia

© 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164, 16–25 24 M. J. M. CHRISTENHUSZ ET AL. simplicia, cordata, minute denticulata, ad apicem assistance and company in the field. We thank Chris- subacuminata, chartacea, palmatinervia; petiolus topher Davis for technical support in the BM her- ruber; stipulae minutae, triangulares. Inflorescentiae barium. We are also very grateful to Sandra Knapp paniculatae, multiflorae, roseae, longe pedunculatae, and to the Natural History Museum Enhancement villoso-tomentosae. Sepala 4 vel 5, magis minusve Fund, which financed the expedition to Guatemala. distincta, lanceolata, valvata, reflexa, ad basin 2 vel Philip Oswald is gratefully acknowledged for his 3 glandulas et trichomata moniliformia rosea fer- skilled assistance with the Latin description. entia. Petala nulla. Stamina 8–12, libera; filamenta glabra; antherae lanceolatoblongae, dorsifixae, rimis REFERENCES apicalibus dehiscentes. Ovarium 4- vel 5-loculare,

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