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13. Systematics of Thomandersia Baill

Author

Wortley, Alexandra H.

Subjects
582.17
Abstract

This thesis addresses three aspects of the systematics of Thomandersia. Firstly, a taxonomic account of Thomandersia is provided. Secondly, the anatomy of Thomandersia is described. Finally, the phylogenetic position of Thomandersia in Lamiales is investigated and the potential of morphological and molecular datasets to resolve relationships in Lamiales is assessed. Six species of Thomandersia are recognised, based upon previous taxonomic treatments, an assessment of variability within the genus, and a rationale for describing infrageneric taxa. An improved key to species, species descriptions, distribution maps and illustrations are presented. A preliminary analysis of molecular sequence data suggests that previous, morphology-based classifications of Thomandersia in Acanthaceae do not reflect phylogenetic relationships. The floral and wood anatomy of Thomandersia are reexamined in this light and discussed in the context of Lamiales. Unique characters of Thomandersia include a particularly large calycine nectary, expanded placentas, irregular corolla aestivation, and spherical, scaly seeds. Thomandersia is found to share anatomical features with all other Lamiales investigated. Detailed anatomical studies of retinacula, a character shared with Acanthaceae, and extrafloral nectaries, which may be homologous to nectaries in other Lamiales, are presented. The majority of anatomical characters are homoplastically-distributed in Lamiales and therefore of little use for diagnosing monophyletic groups. Morphological and molecular phylogenetic investigations support the resurrection of Thomandersiaceae, a family of isolated phylogenetic position with a large number of molecular and morphological autapomorphies. At the same time, the investigations highlight problems in resolving interfamilial relationships in Lamiales. The ultimate aim of phylogenetic analysis in Lamiales is an accurately-resolved tree with stronglysupported relationships between all taxa. Morphological characters are of limited use in achieving this goal: when a large morphological matrix is combined with molecular data only small, poorly-supported increases in resolution are achieved. The increasing availability of molecular sequence data is expected to make it possible, in the near future, to resolve an accurate, supported phylogeny of Lamiales and elucidate the sister group relationships of isolated taxa such as Thomandersiaceae.

Published
2004

18. New insights into the origin of buckwheat cultivation in southwestern China from pollen data.

Author

Yao, Yi‐Feng, Song, Xiao‐Yan, Xie, Gan, Tang, Ye‐Na, Wortley, Alexandra H., Qin, Feng, Blackmore, Stephen, Li, Cheng‐Sen, and Wang, Yu‐Fei

Subjects
POLLEN, BUCKWHEAT, AGRICULTURE, AGRICULTURAL intensification, PALEOECOLOGY, HOLOCENE Epoch
Abstract

Summary: Buckwheat is an important crop which originated in China and spread widely across Eurasia. However, exactly where in China domestication took place remains controversial. Archaeological and palynological records suggest a longer cultivation history of buckwheat in northern China than in southwestern China, but this conflicts with phylogenetic evidence implicating southwestern China as the centre of origin and diversity of buckwheat.We investigate alternative methodologies for inferring the occurrence of buckwheat cultivation and suggest that relative abundance could provide a reliable measure for distinguishing between wild and cultivated buckwheat in both present‐day and fossil samples.Approximately 12 800‐yr palaeoecological record shows that Fagopyrum pollen occurred only infrequently before the early Holocene. As southwestern China entered the early agricultural period, c. 8000–7000 yr ago, a slight increase in abundance of Fagopyrum pollen was observed. Approximately 4000 yr ago, concurrent with the Pu minority beginning to develop dry‐land agriculture, the abundance of Fagopyrum pollen increased significantly, suggesting the cultivation of this crop. Fagopyrum pollen rose to a maximum value c. 1270 yr ago, suggesting an intensification of agricultural activity.These findings fill a gap in the Fagopyrum pollen record in southwestern China and provide new indications that early cultivation may have occurred in this region. [ABSTRACT FROM AUTHOR]

Published
2023
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19. Herbaria are a major frontier for species discovery

Author

Bebber, Daniel P., Carine, Mark A., Wood, John R. I., Wortley, Alexandra H., Harris, David J., Prance, Ghillean T., Davidse, Gerrit, Paige, Jay, Pennington, Terry D., Robson, Norman K. B., Scotland, Robert W., and Wake, David B.

Published
2010

33. EVOLUTION OF ANGIOSPERM POLLEN. 5. EARLY DIVERGING SUPERASTERIDAE (BERBERIDOPSIDALES, CARYOPHYLLALES, CORNALES, ERICALES, AND SANTALALES) PLUS DILLENIALES.

Author

Ying Yu, Wortley, Alexandra H., Lu Lu, De-Zhu Li, Hong Wang, and Blackmore, Stephen

Subjects
ANGIOSPERMS, POLLEN, BERBERIDOPSIDALES, CARYOPHYLLALES, UMBELLALES, DILLENIALES
Abstract

This study, the fifth in a series investigating palynological characters in angiosperms, aims to explore the distribution of states for 19 pollen characters on five early diverging orders of Superasteridae (Berberidopsidales, Caryophyllales, Cornales, Ericales, and Santalales) plusDilleniales. To illustrate the character states found in the pollen of this group, we examined pollen grains of 15 species exemplifying 15 families across all studied orders using light, scanning, and transmission electron microscopy.We reconstructed the phylogeny of the early diverging Superasteridae and related taxa with eight genetic markers for 172 genera, using maximumlikelihood (ML) analysis. Nineteen pollen characters were coded for the genera used in this phylogeny and compiled into two morphological matrices using two coding strategies. The characters were then optimized on the newly generated ML tree plus two constrained trees differing in the position of Dilleniales, using three methods of inference. Taxa in this grade show a striking diversity of pollen morphologies, particularly in certain characters such as size, tectum sculpture, and aperture number. The plesiomorphic condition for the early diverging Superasteridae is unambiguously and consistently inferred to comprise monad-dispersed, isopolar, spheroidal, circular in outline, equatorially arranged, tricolpate pollen grains with granular aperture membranes, a smooth tectum, and endexine present. We identify diagnostic character states and synapomorphies for several monophyletic groups, and explore the palynological evidence thatmay shed light on some unresolved relationships. For example, the hypothesis that Dilleniales is sister to Superrosidae is better supported than alternative hypotheses, being consistent with a number of shared palynological state changes including transitions to presence of costae, reticulate tectum, and columellar infratectumstructure. Across this part of the angiospermphylogeny, most state transitions occur repeatedly, and their frequency varies among both clades and characters. We discuss the impact of optimization method, tree topology, and coding strategy upon ancestral state reconstruction. [ABSTRACT FROM AUTHOR]

Published
2018
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34. Aframomum sericeum Dhetchuvi & D. J. Harris 2011, sp. nov

Author

Dhetchuvi, Jean-Baptiste, Wortley, Alexandra H., and Harris, David J.

Subjects
Tracheophyta, Zingiberaceae, Liliopsida, Zingiberales, Biodiversity, Aframomum, Plantae, Aframomum sericeum, Taxonomy
Abstract

Aframomum sericeum Dhetchuvi & D.J.Harris, sp. nov. (Fig. 1) Aframomo sulcato similis sed pagina abaxiali foliorum dense tomentosa differt. Aframomum sp. D in Harris (2002: 247). Type:��� GABON. Mpassa Forest Reserve, Makokou, 0�� 34��� N, 12�� 52��� E, 18 November 1994, M. M . Dhetchuvi 1725 (holotype BR!, isotype WAG!). Clump-forming herbs to 6 m. Rhizomes to 15 mm in diameter, reddish-brown when dry. Stems often swollen up to 4 cm in diameter at base. Leaf sheaths with rounded and branched transverse and longitudinal ridges, glabrous, occasionally ciliate at edges. Ligules rounded, to 9 mm, bilobed towards tip, glabrous. Pseudopetioles to 10 mm, glabrous. Leaves narrowly elliptic, to 55 �� 11 cm, base slightly asymmetric, apex caudate, acumen ca. 10 mm, margin glabrous, glabrous adaxially, tomentose abaxially, with erect, swollenbased trichomes to 0.5 mm long on laminae, midribs tomentose, secondary veins usually obscured by strands of free hypodermal sclerenchyma adaxially when dry, clearly visible abaxially. Inflorescences arising at or close to the leaf bases, occasionally on rhizomes to 40 cm away, usually branched, each branch bearing ca. 2 flowers, peduncles to 20 cm, borne at or below ground level for most of their length. Flowers trumpet-shaped, delicate. Calyx tubular, greenish to purple. Corolla tubular, dark reddish purple, dorsal petal to 7 cm, lateral petals ca. 4 cm. Labellum pale purple, to 7 �� 5 cm, forming a tube with dorsal petal. Stamen included, anther crest to 5 mm, horns to 5 mm, sometimes forked at tips, anther thecae dehiscing for lower three-quarters of their length. Nectaries paired, free for most of their length. Fruits ellipsoid, to 6.0 �� 3.5 cm, distinctly ridged, greenish, ripening bright red, persistent calyx forming beak to 3 cm long, persistent bracts at base, pulp sweet and acidic to taste. Seeds ellipsoid, to 5 �� 3 mm, dark brown, smooth. Etymology:���Named for the dense covering of hairs on the leaves abaxially. Distribution:���Central and eastern Cameroon, central and northern Gabon, southern Central African Republic, northern Republic of Congo, on cleared land, around villages, fields and roads, occasionally in Gilbertiodendron dewevrei forests, at 350���620 m elevation. Additional specimens examined:��� CAMEROON. Mbalmayo, 3�� 31��� N, 11�� 30��� E, 24 March 1981, W . Meijer 15218 (BR!, MO!, P!, WAG!); Lomi��, 3�� 10��� N, 13�� 38, E, 590 m, 18 November 1965, A . J.M. Leeuwenberg 6785 (BR!, P!, WAG!); River Ja, 3�� 01��� N, 12�� 21��� E, G . L. Bates s.n. (BM!); Doum��, 4�� 14��� N, 13�� 26��� E, 11 September 1960, F . J. Breteler 225 (P!, WAG!); 48 km S of Yaound��, road to Mbalmayo, 3�� 25��� N, 11�� 30��� E, 22 November 1977, E . Westphal & J. M.C. Westphal-Stevels 9754 (WAG!); 15 km S of Mbalamayo, 3�� 25��� N, 11�� 30��� E, 25 November 1977, E . Westphal & J. M.C. Westphal-Stevels 9760 (WAG!); Yaound��, cultivated, 17 December 1976, E . Westphal & J. M.C. Westphal-Stevels 9370 (P!, WAG!); East of Yokadouma, road to Central African Republic, 3�� 25��� N, 15�� 10��� E, 17 March 1981, W . Meijer 15133 (MO!, WAG!); Nkolembembe, 65 km SE Akonolinga, 3�� 15��� N, 12�� 32��� E, 5 June 1981, J . N. Asonganyi 188 (P!); 18 km from Yaound�� to Mbalmayo, 3�� 41��� N, 11�� 31��� E, 10 April 1973, R . Letouzey 12247 (P!, YA!). GABON: Lop��, 0�� 10��� S, 11�� 35��� E, 8 November 1993, M . M. Dhetchuvi 1144 (BR!, BRLU!), 1146 (BRLU!), 1148 (BR!); 9 November 1993, M . M. Dhetchuvi 1161 (BRLU!); 12 November 1993, M . M. Dhetchuvi 1212 (BR!, BRLU!); Lop��, 16 July 1997, J . Lejoly 93/141 (BRLU!); Makand��, 0�� 41���' S, 11�� 54��� E, 17 November 1993, M . M. Dhetchuvi 1260 (BRLU!); 11 November 1994, M . M. Dhetchuvi 1715 A (C!); Lop�� ��� Okanda Reserve, ca. 38 km WSW of Boou��, 0�� 15��� S, 11�� 35��� E, September 1984, M . E. Rogers 151 (E!), 152 (E!); Makokou, 0�� 34��� N, 12 ��52��� E, 500 m, 15 May 1985, L . Dorr & Barnett 4277 (K!, P!, WAG!); Belinga, 1�� 08��� N, 13�� 12��� E, May 1982, C . Tutin 5 (K!); Ogoou�����Ivindo, 7 km on road from Makokou to Okondja, 0�� 32��� N, 12�� 55��� E, 550 m, 23 December 2001, J . J. Wieringa, C. C.H. Jongkind, J. G. Schoonhoven, & M. Mbombet 3527 (WAG!). REPUBLIC OF CONGO: 55 km SW of Souank��, 1�� 56��� N, 13�� 54��� E, 25 November 1991, D. J . Harris 3266 (E!); 52 km SW Souank��, road to Garabinzam, 1�� 56��� N, 13�� 54��� E, 9 November 1991, D. W . Thomas 8797 (MO!); Souank�� Airport, 2�� 00��� N, 14�� 10��� E, 2 December 1991, D. J . Harris 3280 (E!). CENTRAL AFRICAN REPUBLIC: Bayanga, 2�� 55��� N, 16�� 12��� E, 17 November 1997, D. J . Harris 5633 (E!), 5634 (E!), 5635 (E!); 2 December 1997, D. J . Harris 5653 (E!); Babongo Stream, confluence with Sangha River, 2�� 59��� N, 16�� 13��� E, 10 November 1997, D. J . Harris 5614 (E!); Ndakan, 2�� 21��� N, 16�� 09��� E, 350 m, 9 October 1988, D. J . Harris 1366 (MO!); 2�� 23��� N, 16�� 09��� E, 350 m, 20 October 1988, D. J . Harris 1444 (MO!); 12 km S of Lidjombo, 2�� 34��� N, 16�� 05��� E, 350 m, 28 March 1994, D. J . Harris 4851 (E!). EQUATORIAL GUINEA: Asoc Inselberg, 15 km from Mongomo, 1�� 27��� N, 11�� 20��� E, 620 m, 5 June 2002, I . Parmentier & Esono 3725 (BRLU!), 3688 (BRLU!). Aframomum sericeum may be recognised in the field by its large leaves with erect hairs on the lamina and midrib below, dark red corolla and large, ridged fruits. In the herbarium additional useful characters for identification include free strands of hypodermal sclerenchyma cells (Lock & Hall 1975) which can be observed using a ��10 lens on air-dried leaves, and transverse ridging of the leaf sheath. There is some variability in vegetative characters within A. sericeum: occasionally the transverse ridges on the leaf sheath are absent and some specimens (e.g. Tutin 5 and Rogers 151), have almost sessile young leaves. The midrib can also become glabrous towards the base of the leaf with age., Published as part of Dhetchuvi, Jean-Baptiste, Wortley, Alexandra H. & Harris, David J., 2011, A new species of Aframomum (Zingiberaceae) from Central Africa, pp. 31-34 in Phytotaxa 28 on pages 31-33, DOI: 10.11646/phytotaxa.28.1.4, http://zenodo.org/record/4894254, {"references":["Harris, D. J. (2002) The vascular plants of the Dzanga-Sangha Reserve, Central African Republic. National Botanic Garden (Belgium), Meise, 274 pp.","Lock, J. M. & Hall, J. B. (1975) Taxonomic studies in the genus Aframomum (Zingiberaceae). Boissiera 24: 225 - 231."]}

Published
2011
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35. A new species of Aframomum (Zingiberaceae) from Central Africa

Author

Dhetchuvi, Jean-Baptiste, Wortley, Alexandra H., and Harris, David J.

Subjects
Tracheophyta, Zingiberaceae, Liliopsida, Zingiberales, Biodiversity, Plantae, Taxonomy
Abstract

Dhetchuvi, Jean-Baptiste, Wortley, Alexandra H., Harris, David J. (2011): A new species of Aframomum (Zingiberaceae) from Central Africa. Phytotaxa 28: 31-34, DOI: 10.11646/phytotaxa.28.1.4, URL: http://biotaxa.org/Phytotaxa/article/view/phytotaxa.28.1.4

Published
2011

49. Phylogenetic relationships in the Pterygiella complex ( Orobanchaceae) inferred from molecular and morphological evidence.

Author

Dong, Li-Na, Wang, Hong, Wortley, Alexandra H., Lu, Lu, and Li, De-Zhu

Subjects
OROBANCHACEAE, PLANT phylogeny, PLANT morphology, MOLECULAR biology, PLANT classification, SEEDS, SCANNING electron microscopy
Abstract

The Pterygiella complex, i.e. Pterygiella, Phtheirospermum, Pseudobartsia and Xizangia, is controversial in terms of both its relationships and taxonomic status. The genera of the complex are all species-poor and endemic to eastern Asia. In this study, we sampled all taxa in the complex for seven genic regions [ atpB- rbcL, atpH- I, psbA- trnH, rpl16 intron, trnL- F, trnS- G and internal transcribed spacer ( ITS)], which were analysed separately and in combination. We examined capsule and seed morphology of these genera using scanning electron microscopy ( SEM). Our results indicate that the complex is polyphyletic and comprises two clades. The first, designated ' Pterygiella complex I', includes only Phtheirospermum japonicum. This clade is uniquely diagnosed by its papery yellow capsule and reticulate secondary thickening on the seed coat. The second clade, ' Pterygiella complex II', includes Phtheirospermum tenuisectum, P. parishii, P. muliense, Pseudobartsia, Xizangia and Pterygiella. These taxa share a coriaceous capsule. Pterygiella is monophyletic and is characterized by eglandular, unicellular, pilose hairs on the capsule and hook-like protuberances on the horizontal ridges of the striate or reticulate seed coat. Excluding P. japonicum, the remaining taxa of Phtheirospermum cluster together and are sister to Pterygiella. Xizangia bartschioides and Pseudobartsia yunnanensis are separated from Pterygiella and Phtheirospermum, respectively, and are supported as genera by molecular and morphological evidence. © 2013 The Linnean Society of London [ABSTRACT FROM AUTHOR]

Published
2013
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50. Efficiency of DNA barcodes for species delimitation: A case in Pterygiella Oliv. (Orobanchaceae).

Author

Li-Na DONG, WORTLEY, Alexandra H., Hong WANG, De-Zhu LI, and Lu LU

Subjects
*CASE studies, *DNA, *BAR codes, *CULTIVARS, *PLANT species
Abstract

DNA barcoding is becoming an increasingly popular means to identify species. The obscure discrimination in the genus Pterygiella calls into question the re-assessment of the criterion for species delimitation. We collected 20 individuals, representing all five described species of this genus in its distributional range. The aim was to use three proposed barcode DNA regions ( rbcL, matK, and ITS) to diagnose Pterygiella species, and examine which barcode is more suitable for discerning the congeneric and related species. The results showed that the core barcodes matK and rbcL were comparatively less effective. However, the ITS region, especially ITS-1 and ITS-2, successfully identified all species in the genus. Furthermore, the secondary structure of ITS-2 RNA, especially compensatory base changes, appears complementary to classical primary sequence analysis for DNA barcoding. [ABSTRACT FROM AUTHOR]

Published
2011
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