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Ovules and seeds in Acalyphoideae (Euphorbiaceae): structure and systematic implications

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Abstract

Acalyphoideae, the largest subfamily of Euphorbiaceae, are investigated with respect to ovule and seed structure on the basis of 172 species of 80 genera in all 20 tribes of Acalyphoideae sensu Webster. All species of Acalyphoideae examined have bitegmic ovules with a non-vascularized inner integument. However, noticeable differences exist among and sometimes within the genera in the thickness of the inner and outer integument, the presence or absence of vascular bundles in the outer integument, whether ovules are pachychalazal or not, the presence or absence of an aril, seed coat structure (in terms of the best-developed mechanical cell-layer), and the shape of cells constituting the exotegmen. For the latter two characters, two different types of seed coat (i.e., "exotegmic" and "exotestal") and three different types of exotegmic cell (i.e., palisadal, tracheoidal and ribbon-like) were distinguished. Comparisons showed that three tribes Clutieae, Chaetocarpeae and Pereae are distinct from the other Acalyphoideae as well as from the other Euphorbiaceae in having an exotestal seed coat with a tracheoidal exotegmen. The tribe Dicoelieae is also distinct from the other Acalyphoideae in having an exotegmic seed that is composed of ribbon-like cells of exotegmen (i.e., cells both longitudinally and radially elongated, sclerotic and pitted). The tribe Galearieae, which should be treated as a distinct family Pandaceae, is also distinct from the other Acalyphoideae in having an exotegmic seed with a tracheoidal exotegmen (i.e., cells longitudinally elongated, sclerotic and pitted). The remaining genera of Acalyphoideae always have an exotegmic seed with a palisadal exotegmen (i.e., cells radially elongated, sclerotic and pitted). The shared palisadal exotegmen supports the close affinity of Acalyphoideae (excluding five tribes) with Crotonoideae and Euphorbioideae. Within the remaining genera of Acalyphoideae, a significant diversity is found in ovule and seed morphology with respect to the thickness of the inner and outer integument, the size of chalaza, vascularization of an outer integument and an aril.

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References

  • Airy Shaw HK (1975) The Euphorbiaceae of Borneo. Kew Bull Add Ser 4:1–245

    Google Scholar 

  • Airy Shaw HK (1981) The Euphorbiaceae of Sumatra. Kew Bull 35:577–700

    Google Scholar 

  • Angiosperm Phylogeny Group (2003) An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II. Bot J Linn Soc 141:399–436

    Google Scholar 

  • Boesewinkel FD, Bouman F (1984) The seed: structure. In: Johri BM (ed) Embryology of angiosperms. Springer, Berlin Heidelberg New York, pp 567–610

  • Chase MW, Zmarzty S, Dolores Lledo M, Wurdack KJ, Swensen SM, Fay MF (2002) When in doubt, put it in Flacourtiaceae: a molecular phylogenetic analysis based on plastid rbcL DNA sequences. Kew Bull 57:141–181

    Google Scholar 

  • Corner EJH (1976) The seeds of dicotyledons. Cambridge University Press, Cambridge

  • Govaerts R, Frodin DG, Radcliffe-Smith A (2000) World checklist and bibliography of Euphorbiaceae (with Pandaceae). Redwood, Trowbridge, Wiltshire, UK

  • Hurusawa I (1954) Eine nochmalige Durchsicht des herkömmlichen Systems der Euphorbiaceen im weiteren Sinne. J Fac Sci Univ Tokyo, Sect 3, Bot 6:209–342

    Google Scholar 

  • Meeuse ADJ (1990) The Euphorbiaceae auct. plur., an unnatural taxon. Eburon, Delft

  • Nowicke JW, Takahashi M (2002) Pollen morphology, exine structure and systematics of Acalyphoideae (Euphorbiaceae). Part 4. Tribes Acalypheae pro parte (Erythrococca, Claoxylon, Claoxylopsis, Mareya, Mareyopsis, Discoclaoxylon, Micrococca, Amyrea, Lobanilia, Mallotus, Deuteromallotus, Cordemoya, Cococceras, Trewia, Neotrewia, Rockinghamia, Octospermum, Acalypha, Lasococca, Spathiostemon, Homonoia), Plukenetieae (Haematostemon, Astrococcus, Angostyles, Romanoa, Eleutherostigma, Plukenetia, Vigia, Cnesmone, Megistostigma, Sphaerostylis, Tragiella, Platygyna, Tragia, Acidoton, Pachystylidium, Dalechampia), Omphaleae (Omphalea), and discussion and summary of the complete subfamily. Rev Palaeobot Palynol 121:231–336

    Article  Google Scholar 

  • Nowicke JW, Takahashi M, Webster GL (1998) Pollen morphology, exine structure and systematics of Acalyphoideae (Euphorbiaceae). Part 1. Tribes Clutieae (Clutia), Pogonophoreae (Pogonophora), Chaetocarpeae (Chaetocarpus, Trigonopleura), Pereae (Pera), Cheiloseae (Cheilosa, Neoscortechinia), Erismantheae pro parte (Erismanthus, Moultonianthus), Dicoelieae (Dicoelia), Galearieae (Galearia, Microdesmis, Panda) and Ampereae (Amperea, Monotaxis). Rev Palaeobot Palynol 102: 115–152

    Google Scholar 

  • Nowicke JW, Takahashi M, Webster GL (1999) Pollen morphology, exine structure and systematics of Acalyphoideae (Euphorbiaceae). Part 2. Tribes Agrostistachydeae (Agrostistachys, Pseudoagrostistachys, Cyttaranthus, Chondrostylis), Chrozophoreae (Speranskia, Caperonia, Philyra, Ditaxis, Argythamnia, Chiropetalum, Doryxylon, Sumbaviopsis, Thyrsanthera, Melanolepis, Chrozophora), Caryodendreae (Caryodendron, Discoglypremna, Alchorneopsis), Bernardieae (Bernardia, Necepsia, Paranecepsia, Discocleidion, Adenophaedra) and Pycnocomeae (Pycnocoma, Droceloncia, Argomuellera, Blumeodendron, Podadenia, Ptychopyxis, Botryophora). Rev Palaeobot Palynol 105: 1–62

    Article  Google Scholar 

  • Pax F (1890) Euphorbiaceae. In Engler A, Prantl K (eds) Die Natürlichen Pflanzenfamilien, 1st edn, vol 3(5). W. Engelmann, Leipzig, pp 1–119

  • Pax F, Hoffman K (1922) Euphorbiaceae-Phyllantheae. In: Engler A (ed) Das Pflanzenreich IV. 147. XV. (Heft 81):1–349

  • Pax F, Hoffmann K (1931) Euphorbiaceae. In Engler A, Prantl K (eds) Die Natürlichen Pflanzenfamilien, 2nd edn, vol 2, 19c. W. Engelmann, Leipzig, pp 11–233

  • Radcliffe-Smith A (1987) Segregate families from the Euphorbiaceae. Bot J Linn Soc 94:47–66

    Google Scholar 

  • Schmid R (1986) On cornerian and other terminology of angiospermous and gymnospermous seed coats: historical perspective and terminological recommendations. Taxon 35:476–491

    Google Scholar 

  • Soltis DE, Soltis PS, Chase MW, Mort ME, Albach DC, Zanis M, Savolainen V, Hahn WH, Hoot SB, Fay MF, Axtell M, Swensen SM, Prince LM, Kress WJ, Nixon KC, Farris JS (2000) Angiosperm phylogeny inferred from 18S rDNA, rbcL, and atpB sequences. Bot J Linn Soc 133:381–461

    Article  Google Scholar 

  • Takahashi M, Nowicke JW, Webster GL (1995) A note on remarkable exines in Acalyphoideae (Euphorbiaceae). Grana 34:282–290

    Google Scholar 

  • Takahashi M, Nowicke JW, Webster GL, Orli SS, Yankowski S (2000) Pollen morphology, exine structure, and systematics of Acalyphoideae (Euphorbiaceae). Part 3. Tribes Epiprineae (Epiprinus, Symphyllia, Adenochlaena, Cleidiocarpon, Koilodepas, Cladogynos, Cephalocrotonopsis, Cephalocroton, Cephalomappa), Adelieae (Adelia, Crotonogynopsis, Enriquebeltrania, Lasiocroton, Leucocroton), Alchorneae (Orfilea, Alchornea, Coelebogyne, Aparisthmium, Bocquillonia, Conceveiba, Gavarretia), Acalypheae pro parte (Ricinus, Adriana, Mercurialis, Leidesia, Dysopsis, Wetria, Cleidion, Sampantaea, Macaranga). Rev Palaeobot Palynol 110: 1–66

    Article  PubMed  Google Scholar 

  • Tokuoka T, Tobe H (1995) Embryology and systematics of Euphorbiaceae sens. lat.: a review and perspective. J Plant Res 108:97–106

    Google Scholar 

  • Tokuoka T, Tobe H (1998) Ovules and seeds in Crotonoideae (Euphorbiaceae): structure and systematic implications. Bot Jahrb Syst 120:165–186

    Google Scholar 

  • Tokuoka T, Tobe H (2001) Ovules and seeds in subfamily Phyllanthoideae (Euphorbiaceae): structure and systematic implications. J Plant Res 114:75–92

    Google Scholar 

  • Tokuoka T, Tobe H (2002) Ovules and seeds in subfamily Euphorbioideae (Euphorbiaceae): structure and systematic implications. J Plant Res 115:361–374

    Article  PubMed  Google Scholar 

  • Von Teichman I, van Wyk AE (1991) Trends in the evolution of dicotyledonous seeds based on character associations, with special reference to pachychalazy and recalcitrance. Bot J Linn Soc 105:211–237

    Google Scholar 

  • Webster GL (1975) Conspectus of a new classification of the Euphorbiaceae. Taxon 24:593–601

    Google Scholar 

  • Webster GL (1987) The saga of the spurges: a review of classification and relationships in the Euphorbiales. Bot J Linn Soc 94:3–46

    Google Scholar 

  • Webster GL (1994a) Classification of the Euphorbiaceae. Ann Mo Bot Gard 81:3–32

    Google Scholar 

  • Webster GL (1994b) Synopsis of the genera and suprageneric taxa of Euphorbiaceae. Ann Mo Bot Gard 81:33–144

    Google Scholar 

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Acknowledgements

The study was supported by a Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (13740488) and in part by the Global Environment Research Fund, Japan.

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Correspondence to Toru Tokuoka.

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Tokuoka, T., Tobe, H. Ovules and seeds in Acalyphoideae (Euphorbiaceae): structure and systematic implications. J Plant Res 116, 355–380 (2003). https://doi.org/10.1007/s10265-003-0116-4

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