Frida Stångberg

Phylogenetics and taxonomy of the G o r t e r i a c l a d e (Asteraceae - Arctotideae)

Frida Stångberg

Phylogenetics and taxonomy of the Gorteria clade (Asteraceae-Arctotideae)

Frida Stångberg

©Frida Stångberg, Stockholm University 2014 Cover illustration: Gorteria parviligulata. Photo by Frida Stångberg

ISBN 978-91-7447-896-9 Printed in Sweden by Universitetsservice US-AB, Stockholm 2014 Distributor: Department of Ecology, Environment and Plant Sciences

“…Thule hujus australis gazas speciosas detegendi gratia, lætus cucurri, sudavi et alsi.” C.P. Thunberg

Abstract

This thesis deals with the systematics of the Gorteria-Gazania-Hirpicium- clade within the tribe Arctotideae-Gorteriinae in the angiosperm family As- teraceae. The group is found in southern Africa, with many representatives in the Greater Cape Floristic Region in South Africa, an area known for its high species richness and endemism. Specifically, species delimitation within Gorteria and its intergeneric relationships to Hirpicium and Gazania were investigated.

Previous phylogenetical studies showed that the two shrubby Hirpicium alienatum and H. integrifolium were more closely related to the herbaceous genus Gorteria than to remaining species of Hirpicium. During field studies additional proof of their affinity was found when these two, like Gorteria, were found to have capitulum diaspores.

Gorteria was phylogenetically investigated with a large number of samples from different populations of G. diffusa, a species showing striking variation in ray floret coloration. The study showed that the current division of the genus into three species (Gorteria corymbosa, G. diffusa and G. personata) was not supported and it was also shown that the two Hirpicium species were not sister to but nested within a paraphyletic Gorteria. The necessary nomenclatural changes were made including the new combination Gorteria alienata but left remaining species of Hirpicium unassigned to a genus because the type of Hirpicium was included in Gorteria.

When the intergeneric relationship between Gorteria, Gazania and the remaining species of Hirpicium were investigated in detail it was shown that an additional four species of Hirpicium had also evolved from an ancestor within Gorteria. The generic name Berkheyopsis was resurrected for the morphologically deviating Hirpicium echinus while a new genus, Roessleria, was described for the remaining species of Hirpicium. There was high support for a monophyletic Gazania even though the relationship among the genera was unresolved.

List of papers

This thesis is based on the following papers, referred to in the text by their Roman numerals.

I Stångberg F.K. 2009. Diaspore capitula in Hirpicium supports close evolutionary relationship to Gorteria (Asteraceae– Arctotideae). South African Journal of Botany 75: 600–605.

II Stångberg F., Ellis A.G. & Anderberg A.A. 2013. Evolutiona- ry relationships in Gorteria: A re-evaluation. Taxon 62: 537– 549.

III Stångberg F. & Anderberg A.A. 2014. Morphology and taxonomic reclassification of Gorteria (Asteraceae). Willdenowia 44: 97–109.

IV Stångberg F. & Anderberg A.A. Intergeneric relationships in the Gazania-Gorteria-Hirpicium clade of Arctotideae- Gorteriinae, with description of a new genus, Roessleria. Manu- script.

Published papers are reproduced with permission from the publishers.

Disclaimer: A number of new combinations and a new generic name are outlined in the manuscript that constitutes paper IV. It is not of the author's intention to publish the names in this thesis.

All Papers were written by Stångberg with comments and suggestions from the co-authors. Stångberg has conducted all field work, sequence alignments phylogenetic analyses and taxonomical treatments and generated all new sequences for Paper II.

Contents

Introduction ...... 13 Material and Methods ...... 18 Results and Discussion...... 20 Concluding remarks ...... 24 Svensk sammanfattning (Swedish summary)...... 26 Tack! ...... 30 References...... 33

Abbreviations

BM The Natural History Museum (British Museum) BOL University of Cape Town (Bolus Herbarium) CCR The Core Cape Subregion DNA Deoxyribonucleic acid & al. (et al.) Et alii, and others e.g. Exempli gratia, for example ECR The Extra Cape Subregion ETS External Transcribed Spacer G-DC Conservatoire et Jardin botaniques de la Ville de Genève (Candolle’s herbarium) GCFR The Greater Cape Floristic Region ITS Internal Transcribed Spacer K Royal Botanic Gardens (Kew) LINN Linnean Society of London NBG South African National Biodiversity Institute, Cape Town (Compton Herbarium) ndhF NADH dehydrogenase subunit F P-JU Muséum National d'Histoire Naturelle (Jussieu’s herbarium) PRE South African National Biodiversity Institute, Preto- ria rps16 Ribosomal protein S16 S Swedish Museum of Natural History SEM Scanning electron microscopy psbA Photosystem II protein D1 trn Transfer ribonucleic acid UPS Uppsala University UPS-THUNB Uppsala University (Thunberg’s herbarium) viz. Videlicet, namely WIND National Botanical Research Institute, Windhoek

Introduction

South Africa has been “classical ground” to botanist from all parts of the world ever since the Europeans first settled in the Cape in the sixteenth cen- tury. Swedish botanists are no exception. The Linnean disciple Carl Peter Thunberg were among the earliest explorer (1772–1775) of the flora of “Ca- put Bonae Spei” and together with Carl Gustaf Ekeberg, Michael Grubb, and Anders Sparrman the first important Swedish plant collectors in the area. During the centuries they have had many followers (Glen & Germishuizen, 2010). Thunberg is still known as 'The Father of Cape Botany' after the pub- lication of the first comprehensive treatment of the South African plants, his Flora Capensis (1807–1820) (Glen & Germishuizen, 2010). So why South Africa? The Greater Floristic Region (GCFR) of South Africa (and a small portion of southern Namibia) is unique in having an extraordinary species rich flora (Manning & Goldblatt, 2012; Snijman, 2013). The total number of species and number of endemic species are comparable to the high level of biodiversity in tropical rainforests. The region is divided into two subre- gions: The Extra Cape Subregion (ECR), dominated by the succulent karoo biome (Snijman, 2013), and the Core Cape Subregion (CCR, a.k.a. Cape Floristic Kingdom or Cape Floristic Region) where the famous ericoid Fyn- bos biome dominates (Manning & Goldblatt, 2012). The most species rich family of flowering plants in the area is the Asteraceae (the Sunflower family).

Asteraceae (fig. 1) is easily recognized by the typical synflorescence of small florets (tube like disc and/or tongue like ray florets) gathered together in a capitulum and some of the species are well-known to most people, many common as ornamentals. Who has not blown on the spherical gathering of cypselas of a Taraxacum, or picked the ray florets off, one by one, of a Leu- canthemum vulgare, or kneeled in a moment of worship in front of a Tussi- lago farfara on the first sunny day of spring?

Names are necessary for communication and not only scientists have use for the Latin, scientific names on plants. There are often regional vernacular names of plants, whereas the scientific names are the same worldwide. Plant systematics deals with classification and taxonomy of plants and tries to identify monophyletic groups (Hennig, 1966; Farris, 1979). To increase knowledge of such groups, systematists study the evolutionary patterns among plants by reconstruction of phylogenetic trees based on derived

13 (apomorphic) character states in terms of morphological and/or molecular data.

Figure 1. Asteraceae capitulum and floral parts/korg och blomdelar.

The large family Asteraceae is divided into several monophyletic subfami- lies and tribes (Funk & al., 2009). This thesis deals with different issues within one of the tribes, the Arctotideae of the subfamily Cichorioideae. The tribe Arctotideae was recognised for the first time by the great Alexandre Henri Gabriel de Cassini (1816) who studied floral microcharacters in As- teraceae. The Arctotideae was diagnosed by the stylar sweeping hairs having a ring of longer hairs situated below the bifurcation of the style. The tribe contains c. 250 species which are distributed in southern Africa with only one exception, a monotypic genus (genus containing only one single species) found in Australia (Funk & al., 2004). The tribe is still characterized by the typical style morphology, but divided into two subtribes which are more easily recognised: Arctotidinae and Gorteriinae. The plants in Gorteriinae, the group studied for the papers in this thesis, all have strongly connate invo- lucral bracts, unique four-lobed ray florets, alveolate receptacles, and deeply lobed disc floret corollas with reinforced lobe margins (Karis, 2007; Karis & al. 2009). The Gorteriinae comprises eight genera: Gorteria, Hirpicium, Gazania, Berkheya, Cullumia, Cuspidia, Didelta, and Heterorhachis. The three first mentioned, Gorteria, Hirpicium, and Gazania constitutes the Gorteria clade of Arctotideae-Gorteriinae.

Gorteria was originally described by Linnaeus (1759), and before this study, considered as an easily recognized, well diagnosed genus with three species, all annual herbs. The main diagnostic character, used in many determination keys in floras and taxonomic treatments (Roessler, 1959; Dyer, 1975; Gold- blatt & Manning, 2000; Leistner, 2000; Karis, 2007; Manning & Goldblatt, 2012; Snijman, 2013), is the typical diaspore. The fruits are enclosed on the

14 receptacle within the lignified, protecting involucre, and after flowering, the entire capitulum detaches and the seedlings sprout the year after from within it. In previous phylogenetic investigations where Gorteria was included (Funk & al., 2004; Karis, 2006; Funk & Chan, 2008) the genus was always found monophyletic and unproblematic although, two species from another genus, the small shrubs Hirpicium alienatum and H. integrifolium were found to be closest relatives to Gorteria. The variation in colour and spot pattern found in Gorteria diffusa (fig. 2) was poorly documented. Roessler (1959) summed it in one sentence as “in vivo flavae vel ut videtur saepius aurantiacae, partim basi atri-maculatae vel -ocelltae, subtus purpureae vel atrae.” (= in vivo yellow, or more often orange, basal part with dark spots or eye-spots, underside purple or dark). And in floras and field guides it is mentioned as simply orange, with beetle-like markings (Goldblatt & Manning, 2000; le Roux, 2005) or no details about the colour and spots at all (Harvey, 1865; Dyer, 1975).

During a field trip in South Africa in September 2006, after an exceptionally rainy winter, the variation in Gorteria diffusa was a fact (fig. 2). Populations with different coloured ray florets and different numbers of spots on ray florets were found every day. Ellis & Johnson also studied populations of Gorteria diffusa that year and found 14 distinct floral forms (for details see Ellis & Johnson, 2009) that they assumed had been subject to a pollinator- driven evolution. They found that most of the different floral forms were mainly visited by the same insect (Megapalpus capensis), no speciation due to pollinator shift could be proven but still they asked why the different floral forms not are considered different species. Gorteria was, together with all genera in Gorteriinae, revised by Roessler (1959; 1973) and on the distribution maps for Gorteria diffusa, provided by him the distribution was clearly divided into four disjunct areas that we have called “southern”, “middle”, “northern” and “Namibia” (fig. 2). When also a population of woody Gorteria diffusa was discovered (in 2005 by PO Karis and Allan Ellis pers. comm.) on the coast of Namaqualand in Northern Cape (the site is a prohibited diamond area and only occasionally visited by plant collectors with special permit), the prevailing taxonomic treatment of Gorteria became questioned, and that observation became the starting point of this research project.

15 Figure 2. Gorteria diffusa shows a great variation in colours and spot patterns. The map shows western South Africa and southern Namibia with the species’ distribution in is divided into four parts: yellow = ”Namibia”, red = “northern”, green = “middle”, blue = “southern” Paper I discusses a discovery I made during my field trips concerning involucre diaspores in Hirpicium. Paper II discusses relationships within Gorteria by reconstruction of the phylogeny based on molecular data, using parismony and Bayesian methods. The many floral forms are discussed in relation to the phylogeny, and the presumed new species with the woody habit, the four different parts of the distribution of Gorteria diffusa and the relation to Hirpicium alienatum and H. integrifolium are discussed. Paper III presents a revised taxonomy of Gorteria with all necessary recombinations and morphological characteristics of the genus and all its species. In Paper IV relationships among all recognized taxa of Gorteria, Hirpicium and almost all taxa of Gazania were analysed. These three genera were shown by Funk & al. (2004), Karis (2006), and Funk & Chan (2008) to have high support of being a clade (Gorteria clade) in the subtribe Gorteriinae but the inter-specific relationships have never been studied in detail before, and the classification of genus Hirpicium was in great need of revision after the treatment of Gorteria in paper III.

17 Material and Methods

Paper I Since previous workers had suggested Hirpicium alienatum and H. integrifolium to be close relatives (Roessler, 1959) or sisters (Funk & al., 2004; Karis, 2006; Funk & Chan, 2008) to Gorteria I decided to study also populations of these two species together with populations of Gorteria during field trips to South Africa in September 2006 and 2007. Hirpicium integrifolium only grows in the “year round rainfall zone” (Western Cape, South Africa) and five populations were visited. The distribution of Hirpicium alienatum inhabits two disjunct areas, one in the “year round rainfall zone” (Western Cape) and the other part in the “winter rainfall zone” (Namaqualand in Northern Cape). Eight populations of this species were visited from both regions. Plant material were collected and deposited in the Swedish Museum of Natural History (S).

Paper II All taxa of Gorteria (six including subspecies) recognized by Roessler (1959; 1973) were included together with 6 out of 12 of the Hirpicium species. These taxa were all studied and material collected in the field in South Africa (winter and year round rainfall zones) September 2006/2007, Namibia (winter rainfall zone) 2007 and South Africa (summer rainfall zone) in January 2008. Both during collection and sampling, focus was on Gorteria diffusa trying to include as many different floral forms as possible. Gazania serrata was chosen as outgroup and five additional species of Ga- zania were included. DNA was extracted from a total number of 66 samples and sequences from the External Transcribed Spacer (ETS), Internal Tran- scribed Spacer (ITS), both from the nuclear ribosomal DNA, together with the region trnL-F, from the chloroplast genome were produced. All sequences of Gorteria and Hirpicium were produced for this study, in total 189 sequences. The sequence data sets were analysed using maximum parsimony and Bayesian inference methods.

18 Paper III Morphological characters in the collected plant material together with herbarium material from BM, BOL, K, NBG, PRE, S, UPS, and WIND were examined under stereomicroscope, light microscope, and with SEM. The herbaria G-DC, LINN, and UPS-THUNB were visited to study type specimens. A digital image of a type specimen in P-JU was also examined.

Paper IV In this study, all species of Hirpicium and Gorteria were included together with 15 out of 19 species of Gazania. DNA from 24 accessions was extracted and sequenced and sequences for another 25 accessions were also produced to complete the data set. All other DNA sequences were produced for an earlier paper (Paper II) or obtained from GenBank. ETS, ITS, both from the nuclear ribosomal DNA, together with four markers from the plastid genome; the non-coding regions trnL-F, rps16, and trnH-psbA and the coding region ndhF were used. Sequence data of Gazania were obtained from GenBank together with seqences for Berkheya carduoides and Cuspi- dia cernua representing the Berkheya clade of Gorteriinae. Haplocarpha nervosa from the subtribe Arctotidinae was chosen as outgroup and sequences were taken from GenBank. All sequences were aligned using MUSCLE (Edgar, 2004) and after that manually adjusted. Phylogenetical analyses were performed for nuclear and plastid data separately and for all data combined using maximum parsimony and Bayesian inference methods. Herbarium material of all taxa of Hirpicium including type specimens from BM, K, NBG, PRE, S, UPS, and WIND together with digital images of type specimens were examined.

19 Results and Discussion

Paper I When collecting Hirpicium integrifolium in the field in Western Cape (Sep- tember, 2006), I realized how easily the capitula were falling off after flowering so I started to look for seedlings. What I found had never been observed before, namely that the seedlings of Hirpicium integrifolium sprouted in the same way as all Gorteria species, from within previous year's capitulum. When searching for the same phenomenon in Hirpicium alienatum I found that small plants were connected to each other by underground rhi- zome which had not either been documented before. On my next field trip to South Africa (September, 2007) I went to Northern Cape to study populations of Gorteria and Hirpicium and found also in Hirpicium alienatum seedlings sprouting from within old capitula. Even though the diaspore capitulum of Hirpicium alienatum and H. integrifolium were not as lignified as in Gorteria this findings gave further support to these species' close relationship to Gorteria.

Paper II The phylogenetic analyses of Gorteria yielded three tree topologies (the topologies from parsimony and Bayesian analyses were congruent for the different data sets): two trees based on plastid and nuclear data separately, and one tree based on all data combined. The tree based on plastid data was almost without any resolution but showed a Gorteria including Hirpicium alienatum and H. integrifolium as a supported clade. The tree based on nuclear data was much more resolved and showed the same topology as the tree based on all data combined, but the combination of the data sets yielded clades with higher support values. Also these trees supported Hirpicium alienatum and H. integrifolium as an ingroup within Gorteria. What about the many forms of Gorteria diffusa? Samples of Gorteria diffusa from the “southern” part of the distribution ended up, surprisingly together with Gorteria personata subsp. gracilis, as sister to remaining Gorteria including Hirpicium alienatum and H. integrifolium. Gorteria diffusa subsp. parviligulata from the “Namibia” part of the distribution was found to be sister to Gorteria corymbosa. Remaining samples of Gorteria diffusa formed together a well supported clade with G. diffusa from the “middle” and “north-

20 ern” part of the distribution forming a trichotomy with one sample of G. diffusa subsp. calendulacea. Surprisingly, the relation between all samples of the “northern” Gorteria diffusa, including all the different floral forms and the woody specimen from the coast, did not show any resolution. Beside the results concerning Gorteria diffusa, the subspecies of G. personata was shown to be non-monophyletic. Also the relationship between Hirpicium alienatum and H. integrifolium was unresolved, with samples of H. alienatum from Western Cape more closely related to H. integrifolium (only found in Western Cape) than with H. alienatum from Northern Cape.

When I studied the different populations of Gorteria diffusa in the field, I tried not to pay too much attention to the ray floret colour variation or different spots but instead tried to focus also on other characters. One easily seen feature is the number of ray florets in the capitula. This is not often documented in the literature but Roessler (1973 in his addendum to the revision of Gorteriinae) added this character to the diagnosis of Gorteria diffusa subsp. parviligulata and subsp. calendulacea but he did not comment it further. I realized in the field that the plants more or less without exception followed the Fibonacci number series (...5, 8, 13...). Gorteria diffusa from the southern part of the distribution always have eight ray florets and so have Gorteria diffusa subsp. parviligulata. Gorteria diffusa from the “middle” and “northern” parts of the distribution always have 13 ray florets with the exception for the plants found in the most northern part of Northern Cape (Richtersveld) and the sampled specimens from this area formed a well supported group. Further, the samples of Gorteria corymbosa included in the study also split into two strongly supported sister clades corresponding to 8 and 13-rayed specimens.

Paper III It was clear after the phylogenetic study of Gorteria (paper II) that this genus was in great need of a taxonomical revision. Based on observations in the field and in the herbarium material it felt natural to include Hirpicium alienatum and H. integrifolium in Gorteria. The typical diaspore was not the only synapomorphic character state for the genus, also the feature of that only a small portion of the disc florets are hermaphroditic and able to set seed was shared by these two species and other Gorteria. Further, Karis (2006) found a special type of longitudinally striate hairs (in the subtribe found on leaves and stems), on the disc florets in Gorteria, Hirpicium alienatum and H. integrifolium. The two small shrubs share geographical distribution in the GCFR with Gorteria and were two odd representatives in the rather heterogeneous Hirpicium. The phylogenetical results showed us that the relation between these two species was not fully understood and in need of further study. We transferred the two Hirpicium species to Gorteria.

For Gorteria diffusa from the “southern” part of the distribution a new name had to be found and after examination of the type specimen in Paris, we resurrected a name of Cassini, Gorteria piloselloides (≡ Ictinus piloselloides Cass.). Even though Gorteria personata subsp. gracilis is easily distin- guished from “southern” Gorteria diffusa (e.g. by the number of ray florets: 5 and 8 respectively) and their geographical distributions do not overlap, we decided to merge them into one taxon since a split did not have any support in the phylogeny (paper II). In the clade including Namibian representatives of Gorteria we decided to give Gorteria diffusa subsp. parviligulata species rank and the two clades of Gorteria corymbosa were separated into two species. Eight-rayed Gorteria corymbosa (including the type) are found in the Desert Biome in Gariep (Snijman, 2013) in an area known for high level of endemism in several families and have not likely any contact at all with the 13-rayed Gorteria corymbosa not only due to the different geographical patterns but also because of different flowering periods. The 13-rayed Gorte- ria corymbosa is the only autumn-flowering group in Gorteria and we pro- posed a new name for these plants, Gorteria warmbadica. A somewhat un- satisfying decision for remaining Gorteria diffusa was to keep them all together under that name. In the phylogeny (paper II) we could not find any support for the subspecies Gorteria diffusa subsp. calendulacea. One eight- rayed group of plants, also from Gariep, had support and also some other morphological synapomorphies but we found it hard to go further with this group without making the sister group paraphyletic with one sample of Gorteria diffusa subsp. calendulacea outside remaining Gorteria diffusa from the “northern” part of the distribution. One possibility would be to re- strict the name Gorteria diffusa to the “middle” form (the type was collected by Thunberg in that area), and I believe that the eight-rayed Gorteria diffusa from Richtersveld deserves some kind of taxonomic recognition. The Kami- esberg Mountain, where the odd Gorteria diffusa subsp. calendulacea was collected also deserves more attention. This area, in the Northern Cape is defined as an ecogeographical unit by Snijman (2013) and is also known for housing many endemic taxa (Helme & Desmet, 2006; Snijman, 2013). We chose to treat the woody form of Gorteria diffusa just as another of the many forms in Northern Cape.

After the taxonomical treatment of Gorteria in paper III, the number of species in the genus increased from three to eight. The initial hypothesis was that Hirpicium alienatum and H. integrifolium were sister to Gorteria, but given the result of the analysis and by including the type of Hirpicium (Hir- picium alienatum (Thunb.) Druce) in Gorteria, it became necessary to investigate relationships among all remaining Hirpicium as they were left unassigned to genus.

22 Paper IV When, for the first time, all species of Gorteria and Hirpicium were included in the same phylogenetic analyses some interesting results were found. DNA data from the nuclear genome (ETS, ITS) yielded resolution on the species level while the plastid data contributed information on a higher taxonomic level. The phylogeny based on plastid DNA showed high support for a monophyletic Gazania and two other major clades, which however, did not correspond to Gorteria and Hirpicium. Surprisingly, no further relationships between these three major clades were found in any of the data sets. The ten species that were left in Hirpicium after removal of the type (paper III) were in the analyses of plastid and combined data, divided into a northern and southern group (paper IV, fig. 6). Apart from the two species mentioned, also a northern group of four species of Hirpicium was found to be an ingroup in Gorteria. Remaining species of Hirpicium, from the southern part of the distribution, formed together a clade in which two subclades could be identified, one constituted by Hirpicium echinus and the other with the remaining species. It was clear already after paper III that the name Hirpicium not could be used as Gorteria antedates it and after the results of paper IV even more taxonomical changes were needed. The concept of Gazania was left unchanged, the species of Gazania were not shown to be in need of any recombinations on generic level, but the results confirmed what Howis & al. (2009) found; viz. that the species of Gazania are in great need of a taxonomic revision. We merged the four northern Hirpicium species with Gorte- ria. Nothing is known about their capitula, if they act as diaspores or not. These northern species are not as frequently collected as the South African Gorteria species (especially the annual herbs) but hopefully a future field study of these species could bring some light into this issue, and perhaps confirm the presence of capitulum diaspore also in these species, even though they have cypselas with a well developed pappus.

Four out of the six species in the clade of southern Hirpicium species have been studied in the field. And one of them stands out morphologically from the others, viz. Hirpicium echinus, which was found as sister to the others. To place Hirpicium echinus in a genus of its own would make the group with the other five species more homogenous morphologically, and therefore we suggested placing them in a new genus, Roessleria. We believe that further investigation of biogeographical data added to our analyses could yield interesting information about how, when, and from where these groups were dispersed on the African continent.

23 Concluding remarks

The papers of the present thesis have contributed much new insights into the evolutionary relationships within the tribe Arctotideae. Taxonomy is a foun- dation on which rests conservation biology and all other disciplines where species are involved. South Africa (and other biological hot-spots) is special, in that a large quantity of species that are new to science are discovered every year. With the phylogenetic research by systematists, the concepts and number of taxa on different taxonomic level is changed continuously, hopefully to show a more true reflection of the evolution.

Future studies Gorteria alienata and G. integrifolia are in need of a more detailed investigation. The phylogeny based on combined data in paper IV supports a split of Gorteria alienata in a southern and northern part and a morphological investigation of the species together with an extended field work and sampling might lead to a new understanding of the species limits between G. alienata and G. integrifolia.

The genetical background of the exceptional variation in ray floret colour and spot patterns in Gorteria diffusa is still not explained, but for field botanists working in Namaqualand in Northern Cape, the variation is very clear. To address this issue, maybe transcriptome analysis based on next- generation sequencing with an extended phylogenetic study on a population level could be used to explain the variation patterns.

The Hirpicium species now included as members of Gorteria (G. angustifolia, G. antunesii, G. beguinotii, and G. gracilis) are in need of field study. Beside the need of search for capitulum diaspores among these species I would like to further investigate what I have observed in the herbarium material that one of them (Gorteria angustifolia) seem to be a pyrophyte (flowering only after fire), something also reported in Flora Zambesiaca (Pope, 1992), but this species is only sparsely collected and little is known about its biology.

24 Biogeography and dating of the Gazania-Gorteria-Berkheyopsis-Roessleria- clade could shed light on if this Gorteriinae-clade originated in the Greater Cape Floristic Region. An even more interesting approach would be to ex- tend the data sets to include also the Berkheya-clade (Berkheya, Cullumia, Cuspidia and Didelta), with a similar biogeographical distribution, in such an analysis.

Frida studies Gorteria integrifolia in the Swartberg mountains, Western Cape, South Africa.

25 Svensk sammanfattning (Swedish summary)

Sedan européerna bosatte sig i Kapområdet i Sydafrika på 1500-talet har det varit klassisk mark för västerländska botanister. Några av de tidigaste (1700- talet) utforskarna av området var kapten Carl Gustaf Ekeberg, Michael Grubb samt Linnélärjungarna Carl Peter Thunberg och Anders Sparrman och sedan dess har vi blivit många som kommit att fascineras av den sydafrikanska floran. På en yta ungefär motsvarande götalands finns omkring 9400 kärlväxtarter och nästan 70 % av dem är endemiska (växer bara där) och den mest artrika blomväxtfamiljen är Asteraceae (korgblommiga växter).

Hur vi klassificerar och namnsätter arter, släkten och familjer skall helst avspegla evolutionen på ett så korrekt sätt som möjligt. Systematiker kon- struerar släktträd över organismer genom att studera deras egenskaper. Mo- derna lab-tekniker har de senaste decennierna gett oss möjligheten att få fram stora mängder data till våra släktskapsanalyser, i form av DNA- sekvenser. Vissa egenskaper delar organismer pga släktskap (homologier, synapomorfier) men ibland pga parallella utvecklingar av egenskapen (ana- logier, homoplasi).

Med sina ca 24 000 arter är Asteraceae den största blomväxtfamiljen och förekommer på alla jordens kontinenter utom Antarktis. Familjen är omiss- kännlig med sina speciella blomställningar (fig. 1, sid. 12): små blommor (tunglika strålblommor och/eller rörformiga diskblommor) sitter samlade i en korg omgiven av holkfjäll. Välkända representanter är solros, maskros, prästkrage och hästhov.

Den här avhandlingen handlar om en grupp, främst sydafrikanska, korgblommiga växter. Jag har studerat och samlat växter i fält, studerat herbarie- material, rekonstruerat släktskapsträd (fylogenier) baserade på DNA- sekvenser (molekylära data) och med allt detta som grund dragit slutsatser om vilka växter som hör ihop och hur de ska klassificeras på olika nivåer.

Innan denna avhandling ansågs släktet Gorteria vara lätt att känna igen med sina tre arter, samtliga ettåriga örter. En egenskap dessa arter hade gemen- samt var deras ovanliga sätt att sprida sina frukter. Det vanliga inom familjen Asteraceae är hela frukten flyger iväg genom att använda pappus (pensel) som flygorgan (tex maskros, tistlar) men hos Gorteria förvedas korgen efter

26 blomning och innesluter frukterna. Hela blomkorgen fungerar sedan som spridningsenhet (diaspor) och när de nya fröplantorna gror kommer de spi- rande ut ur fjolårets förvedade korg. En annan speciell egenskap hos Gorte- ria är fläckarna vid basen av strålblommorna. Fläckarna finns i bland på alla strålblommor men ibland bara på en, två, tre eller fyra av strålblommorna i en korg. Jag åkte till Sydafrika i september 2006 för att studera och samla växter. I Namaqualand, i Norra Kapprovinsen, insåg jag att Gorteria diffusa hade en otrolig variation i färg och hur fläckarna på blommorna såg ut och var arrangerade (fig. 2, sid. 14), något som inte dokumenterats i floror eller vetenskapliga artiklar. Året innan hade dessutom en population av perenna Gorteria med ett vedartat växtsätt hittats vilket gjorde att den rådande klassi- fikationen av släktets ifrågasattes från flera håll. Detta var startpunkten för mitt doktorandprojekt. Tidigare släktskapsstudier av gruppen där Gorteria ingår tydde på att två arter ur ett annat släkte, Hirpicium, bildar en syster- grupp till Gorteria. Med andra ord finns det stöd för att dessa två arter, Hir- picium alienatum och H. integrifolim, skulle vara närmare släkt med arterna i Gorteria än med övriga arter inom Hirpicium. Hirpicium alienatum och H. integrifolium är till skillnad från arterna i Gorteria fleråriga buskar.

I artikel I rapporterar jag intressanta fynd, gjorda under mina fältstudier i Sydafrika nämligen att de två buskarna Hirpicium alienatum och H. integrifolium har samma typ av diaspor som arterna inom Gorteria. Detta är ytterligare stöd för att de två buskarna är nära släkt med Gorteria.

I artikel II rekonstruerade vi Gorterias släktskapsträd baserat på DNA- sekvensdata. Tidigare studier hade visat att Gorteria diffusas geografiska utbredning är uppdelad i fyra områden (fig. 2). Vi inkluderade alla arter och underarter, 41 olika individer av Gorteria diffusa för att få med alla olika utseenden, inklusive den vedartade, samt individer från artens alla utbred- ningsområden. Resultaten visade att Hirpicium alienatum och H. integrifolium verkligen är en del av Gorteria. Gorteria diffusa från den södra delen av utbredningen visade sig inte alls vara nära släkt med den egentliga G. diffusa (dit artens typ hör) Gorteria diffusa subsp. parviligulata som bara finns i södra Namibia var inte heller närmast släkt med någon annan Gorteria diffusa utan bildade med Gorteria corymbosa (också Namibia och nordvästligas- te Sydafrika) en egen gren i släktträdet. Resultaten visade inget stöd för att Gorteria diffusa från nordvästra Sydafrika (Namaqualand) skulle vara upp- delat i några undergrupper trots den stora variationen i färger och fläckar. Gorteria personata var uppdelad i två underarter men våra resultat visade att dessa inte hörde ihop utan en av underarterna, G. personata subsp. gracilis, var i stället närmast släkt med G. diffusa från den sydliga delen av utbredningen.

I artikel III gjorde vi de namnändringar som resultaten i artikel II visat vara nödvändiga. När en ny art beskrivs finns alltid ett unikt typexemplar associe-

27 rat med det nya namnet på växten i fråga och när ett släkte beskrivs är det en av arterna i släktet som är typ för släktet. När vi visade att Hirpicium alienatum och H. integrifolium egentligen är en del av Gorteria måste de arterna byta namn. Släktet Gorteria beskrevs 1759 av Linné medan Hirpicium är mycket yngre, beskrivet av Cassini 1820. Det äldsta namnet har prioritet och eftersom Hirpicium alienatum är typ för Hirpicium kan inte det släktnamnet användas längre trots att ytterligare tio arter förs till släktet. En sak som jag la märke till under mina fältstudier var att antalet strålblommor hos Gorteria alltid var konstant, fem, åtta eller tretton, i de olika populationerna jag be- sökte. Gorteria corymbosa kunde delas in i två grupper med åtta respektive tretton strålblommor, grupper som dessutom visade sig vara skilda från var- andra geografiskt och i blomningstid samt placerade sig som varandras sys- tergrupper i släktträdet. Typexemplaret för Gorteria corymbosa ligger i her- bariet i Genève så jag tog tåget dit för att konstatera att typen har åtta strål- blommor. Den trettonblommiga gruppen av växter gav vi ett nytt namn, Gor- teria warmbadica efter en ort i södra Namibia där flera exemplar av växten samlats. Gorteria diffusa från de norra och mellersta delarna delades, trots den stora variationen i utseendet, inte upp i nya arter eller underarter eftersom vi inte funnit något sådant stöd i släkträdet utan fick behålla namnet Gorteria diffusa. Däremot upphöjdes G. diffusa subsp. parviligulata till art och för den sydliga gruppen av G. diffusa kunde ett gammalt artepitet, ”piloselloides”, användas.

I artikel IV satte vi Gorteria i ett större sammanhang genom att inkludera deras närmaste släktingar Hirpicium (de arter som blev kvar i släktet efter att H. alienatum och H. integrifolium övergått till Gorteria) och Gazania i en släktskapsanalys återigen baserad på DNA-sekvensdata. Resultatet visade att släktet Gazania är en naturlig grupp men däremot bildade de arter som in- gick i Hirpicium två skilda grupper: en grupp med nordliga arter hörde ihop med Gorteria och en sydlig grupp bildade sin egen gren i släktträdet. Efter namnändringarna som gjordes i artikel III stod det klart att alla ”Hirpicium”- arter var i behov av nytt släktesnamn. Med resultaten från analyserna i artikel IV gjorde vi namnändringar för samtliga tio Hirpicium-arter varav fyra, de nordliga, inkluderades i Gorteria, en fick återta sitt gamla släktesnamn Berkheyopsis, och för de resterande fem arterna beskrevs ett nytt släkte, Ro- essleria.

Gorteria, ett sydafrikanskt släkte med tidigare tre arter, alla ettåriga örter, förändrades till ett släkte med åtta arter av både örter och buskar, och sedan till ett släkte med tolv arter när ytterligare fyra arter perenna örter från Ango- la, Zambia, Zimbabwe, Tanzania och Kenya inkluderades. Släktet Hirpicium är ett minne blott och de tolv arterna ingår nu i Gorteria, Berkheyopsis eller Roessleria.

29 Tack!

Arne! Tänk att du plötsligt kunde tänka dig att bli min handledare och dessutom inte gett upp hoppet om mig! Tack! Du kan verkligen få alla gråa her- barieark till att bli de färgsprakande växter de egentligen är. Tack för att jag har fått äran att glädja dig genom att låta dig använda ditt favoritredskap, rödpennan, så flitigt! PO, tack för att du introducerade mig för växtsystematik i allmänhet och sydafrikanska kompositer i synnerhet, för sällskap, assistans och floristikun- dervisning i fält och herbarier. Tack också för att du älskar att prata om holk- fjäll, tvillinghår och Drège när som helst, dygnet runt. Jürg, tack för att ha varit min biträdande handledare, dock alldeles för långt bort, tack vare dig har jag fått göra spännande bergsbestigningar i Sydafrika, på jakt efter Glischrocolla formosa & al., tack för hjälp med översättning av Roesslers tyska och för oförglömliga fonduekalas!

Tack alla kollegor på botan: Birgitta, Kajsa, Catarina, Sylvain, Niklas och Anbar tack tack supertack! Tack också till er som dragit här ifrån: Arnaud, Jenny, Torsten, Ulrika, JT.

Kent, vad hade jag gjort utan dig? Du har inte bara hjälpt mig med alla sor- ters problem utan också gjort botantiden till Good Times! Tack för ALLT! Magnus, på gott och ont har du varit som en extra storebror för mig, du mås- te ha de rätta receptorerna för de lillasystersubstanser jag utsöndrar. Tack för ovärdelig hjälp och kära avbrott i arbetet, spinning, youtube, grötfrukostar, 300, mojitos, öl och glögg! Markus, min förebild som Asteraceaedoktorand, tack för all hjälp när jag var ny och välbehövligt sällskap vid SEM! Julia, den officiella versionen är ”Tack för sällskap på en trevlig och intensiv vecka i Londons herbarier och Kew's shop och för allt du lärt mig om slem- svampar mm under alla stolliga kurser vi undervisat på tillsammans” den inofficiella versionen är: Vi kör så det ryker! Åsa, tack för att jag fått höra östgötska klinga så underbart skönt alldeles för långt hemifrån, tack för alla stickträffar, jag kanske har lärt dig lägga upp maskor men nu stickar du ju som en gud! Tack också för praktiska avhand- lingstips… Annika, tack för att just du tog över Metalasia och behandlade dem på bästa tänkbara sätt (förutom M. tristis... morr..), mycket bättre än jag hade gjort!

30 Tack för en svinprofessionell vecka i Sydafrika inkl. nära-babian- upplevelser, Planea-fynd och livsfarlig souvenirjakt! Stina, tack för att du köttat på så friskt vid min sida, det har varit en ära att ha varit din fadder men jag undrar vem som tagit hand om vem egentligen. Chen, tack för att du är en solstråle som inte bangar för en liten solosång i fikarummet!

Aelys, min Aelys, vad gjorde jag utan dig? Som den anglofil jag är så ser jag dig mer eller mindre som en gud! Gud eller ej, ditt sällskap på rummet har varit super. Tack!

Tack alla goa exjobbare genom åren! Extra tack till Stefan!

Tack Peter & Ingela för att ni tagit så väl hand om mig när jag stollat omkring i växthusen! Extra tack till Peter för alla trevliga pratstunder om vårt gemensamma favoritresmål!

Rebecka, tack för sällskap på vägen via Grekland, rom+fylogenier i Kransen, Bondegatan, WYG, Stora håret, Skypes gravidjour, France, Hornstulls tem- porära dagis. Jag saknar dig omåttligt, tack för allt stöd, i allt!

Tack för oförglömliga, lyckliga veckor i Afrika: Palle – God knows I love him! Linda – vi passade grymt bra ihop på jakt efter Endonema, med glatt humör, blodiga, genom Stoeben! PO – du är en legendar, vilken ära att ha varit där med dig! Jag ska inte bli sentimental men extra tack för höjdpunk- terna Richtersveld, Marloths naturreservat, Nice, Windhoeks botaniska trädgård, Vergelegen, Eremothamnus, Rosh Pinah, Natal spa, Simonskloof, Agulhas, skorpmiddagar, lyxiga luncher i bakluckan och sist men inte minst Welwitschia (lätt värd den nätta omvägen på ca 200 mil).

Utan dessa hade jag inte börjat eller velat genomlida min doktorandtid: Rebecka tur att jag såg ditt namn på deltagarlistan för påbyggnadskursen i växtsystematik, Julia som uppmuntrade mig att göra exjobb, samtliga med- lemmar av ±0 med Tove & Lina i spetsen, Euterpe – jag får koncentrerat tänka på något helt annat än blommor 2,5 timmar i veckan – otroligt roligt och helande för själen! Mina vänner på botans andra våningsplan Claes, Tove, Martin, Lotta!

Robert McKenzie, thank you for nice company in Namaqualand and for sharing my passion for Arctotideae! Thanks for nice words and cheers when my self-confidence was below zero.

To the nice people I met in South Africa: Jan & Anne-Lise Vlok, Allan Ellis, Annelise le Roux and Laco Mucina thanks for sharing your great knowledge about the South African flora.

Allan & Christina, tack för sällskap och barnvaktning i Sydafrika!

Mamma Trinda & Pappa Göran, tack för att ni grundade mitt biologiintresse så otroligt grundligt! Mamma, tack för alla kattfötter, kaprifoler, nattvioler, grekiska lövkojor, kaktusar, ringblommor, snödroppar, smultron, smörbollar, libbstickor som jag har tvingats lukta på. Pappa, tack för de ca 50 000 utturerna, mandelkubbarna, grodynglen, ström- stararna, sädesärlorna, tranbären, murklorna, örnarna, kräftorna... stimulering av sökande och samlande.

Mimmi, Lisa & Ville, Jonas & Mary, Viktor, Emma Love, Elis, Olle, Stina Mormor Signe Ylva, Klas, Tomas & Keiko

Tage & Gunnar. PO

32 References

Cassini H., 1816. Tableau exprimant les effinités des tribus naturelles de famille des Synantheérées. In: Cuvier, G. (Ed.), Dictionnaire des sciences naturelles 3, Ed. 2. Le Normant, Paris.

Cassini H. 1820. Description d’un nouveau genre de plantes (Hirpicium), précédée d’observations sur l’Œdera alienata de Thunberg, et sur l’Œdera aliena de Jac- quin. Bulletin des Sciences, par la Société Philomatique Paris 1820: 26–27.

Dyer R.A. 1975. The Genera of Southern African Plants 1. Botanical Research Insti- tute, Pretoria.

Edgar R.C. 2004. MUSCLE: multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Research 32 (5): 696-704.

Ellis A.G. & Johnson S.D. 2009. The evolution of floral variation without pollinator shifts in Gorteria diffusa (Asteraceae). American Journal of Botany 96: 793– 801.

Farris J.S. 1979. The information content of the phylogenetic system. Systematic Zoology 28: 483–519.

Funk V.A. & Chan R. 2008. Phylogeny of the spiny African daisies (Compositae, tribe Arctotideae, subtribe Gorteriinae) based on trnL-F, ndhF, and ITS sequence data. Molecular Phylogenetics and Evolution 48:47–60.

Funk V.A., Chan R. & Keeley S.C. 2004. Insights into the evolution of the tribe Arctoteae (Compositae: subfamily Cichorioideae s.s.) using trnL, ndhF, and ITS. Taxon 53: 637–655.

Funk V.A, Susanna A., Steussy T.F. & Bayer R.J. (eds.) 2009. Systematics, Evolu- tion, and biogeography of Compositae. International Association for Plant Tax- onomy, Vienna.

Glen H.F. & Germishuizen G. 2010. Botanical Exploration of Southern Africa: An Illustrated History of Early Botanical Literature on the Cape Flora: Biographical Accounts of the Leading Plant Collectors and Their Activities in Southern Af- rica from the Days of the East India Company Until Modern Times. 2d edition. South African National Biodiversity Institute, Pretoria.

Goldblatt P. & Manning J. 2000. Cape plants. A conspectus of the Cape flora of South Africa. Strelitzia 9: National Botanical Institute of South Africa, Pretoria.

33 Harvey W. H. 1865. Compositae. – Pp. 44 – 530 in: Harvey W. H. & Sonder O. W. (ed.), Flora capensis, being a systematic description of the plants of the Cape Colony, Caffraria and Port Natal 3. L. Reeve, London.

Helme N. & Desmet P.G. 2006. A Description Of The Endemic Flora And Vegeta- tion Of The Kamiesberg Uplands, Namaqualand, South Africa. Report for CEPF/SKEP.

Hennig W. 1966. Phylogenetic systematics. University of Illinois Press. Chicago.

Howis S., Barker N.P. & Mucina L. 2009. Globally grown, but poorly known: Spe- cies limits and biogeography of Gazania Gaert. (Asteraceae) inferred from chloroplast and nuclear DNA sequence data. Taxon 58: 1–12.

Karis P.O. 2006. Morphological data indicates two major clades of the subtribe Gorteriinae (Asteraceae–Arctotideae). Cladistics 22: 199–221.

Karis P.O. 2007. Tribe Arctotideae Cass. Pp. 200–207 in: Kadereit, J.W. & Jeffrey, C. (eds.), The families and genera of vascular plants, vol. 8, Flowering plants: Eudicots; Asterales. Berlin: Springer.

Karis P.O., Funk V.A., McKenzie R.J., Barker N.P. & Chan R. 2009. Arctotideae. Pp. 285–310 in: Funk, V.A., Susanna, A., Stuessy, T. & Bayer, R. (eds.), Sys- tematics, evolution and biogeography of Compositae. Vienna: International As- sociation of Plant Taxonomists.

Leistner O.A. 2000. Seed plants of southern Africa: families and genera. Strelitzia 10. National Botanical Institute, Pretoria.

Linnaeus C. 1759. Systema naturae, ed. 10, 2. Lars Salvius, Stockholm.

Manning J. & Goldblatt P. 2012. Plants of the Greater Cape Floristic Region 1: the Core Cape Flora. Strelitzia 29. South African National Biodiversity Institute, Pretoria.

Pope G.V. 1992. Compositae. In: Pope G.V. (ed.), Flora Zambesiaca. 6, 1. Kew Publishing and Flora Zambesiaca Managing Committee, 1992, London.

Roessler H. 1959. Revision der Arctotideae-Gorteriinae (Compositae). Mitteilungen der Botanischen Staatssammlung München 3: 71–500.

Roessler H. 1973. Nachträge zur Bearbeitung der Arctotideae-Gorteriinae (Compo- sitae). Mitteilungen der Botanischen Staatssammlung München 11: 91–99.

Roux A.-L. le 2005. Namaqualand, South African wild flower guide 1, ed. 3, Bo- tanical Society of South Africa, Cape Town.

Snijman D.A. (ed.). 2013. Plants of the Greater Cape Floristic Region, 2: the Extra Cape flora. Strelitzia 30. South African National Biodiversity Institute, Pretoria.