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Research Article
Endiandra macrocarpa (Lauraceae), a new tree species from south-western China
expand article infoDian-yang Zou‡§, Guan-long Cao§|, Jin-guo Zhang, Lang Li‡, Jie Li‡
‡ Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
§ University of Chinese Academy of Sciences, Beijing, China
| Institute of Botany, Chinese Academy of Sciences, Beijing, China
¶ Administration Bureau of Maguan Gulinqing Provincial Nature Reserve, Wenshan, China

Corresponding author: Lang Li ( lilang@xtbg.ac.cn )

Corresponding author: Jie Li ( jieli@xtbg.ac.cn )

Academic editor: Andrés E. Ortiz-Rodriguez
© 2023 Dian-yang Zou, Guan-long Cao, Jin-guo Zhang, Lang Li, Jie Li.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation: Zou D-y, Cao G-l, Zhang J-g, Li L, Li J (2023) Endiandra macrocarpa (Lauraceae), a new tree species from south-western China. PhytoKeys 224: 183-192. https://doi.org/10.3897/phytokeys.224.102752
Open Access

Abstract

Endiandra macrocarpa, a new species of Endiandra (Lauraceae) from Yunnan Province of south-western China, is here described and illustrated, based on morphological evidence. Compared to other Endiandra species occurring in south China and the adjacent regions in Indochina, this species is mainly characterised by its much larger ellipsoidal fruits (up to 11 × 6 cm), as well as glabrous branchlets and puberulent inflorescences.

Keywords

Endiandra, morphology, taxonomy, tropical montane forest, Yunnan Province

Introduction

The genus Endiandra R. Br. of the Lauraceae family is widely distributed from south China, Indochina, Malesia and Australia to the Pacific Islands (Rohwer 1993; Arifiani 2001; van der Werff 2001). It has approximately 100 species and its diversity is strongly centred in south-eastern Malesia and Australia (Hyland 1989; Arifiani 2001; Cussan et al. 2007). Endiandra was first described by Brown (1810), based on the type species from Australia, Endiandra glauca. The species of the genus can be characterised by alternate, penninerved leaves; axillary or terminal panicles; bisexual flowers with three 2-celled fertile stamens and unprotected fruits on pedicels (Kostermans 1957; Rohwer 1993; van der Werff 2001; Cussan et al. 2007; Li et al. 2008).

According to previous studies of wood and bark anatomy, floral morphology, taxonomy and molecular phylogeny, Endiandra belongs to the basal lineages of the family, in the tribe Cryptocaryeae or the Cryptocarya group and is closely related to Beilschmiedia Nees (Richter 1981; Rohwer 1993; van der Werff and Richter 1996; Rohwer 2000; Chanderbali et al. 2001; Rohwer and Rudolph 2005; Rohwer et al. 2014; Li et al. 2020; Song et al. 2020). Vegetatively, Endiandra is very similar to Beilschmiedia, only flower characters can differentiate the two genera (van der Werff 2001; Arifiani et al. 2012). Typical flowers of Endiandra only have three fertile stamens in the third whorl, whereas Beilschmiedia has nine fertile stamens (Arifiani 2001; van der Werff 2001; Arifiani et al. 2012).

Without any comprehensive revision, Endiandra has so far only been treated in floras or local revisions (e.g. Hyland (1989); Kochummen (1989); Arifiani (2001); Cussan et al. (2007); Li et al. (2008)). In China, there are only three recognised Endiandra species (two endemic) and they are distributed in Yunnan, Guangxi, Hainan and Taiwan (Li et al. 1979; Li et al. 1982; Liang et al. 1985; Li et al. 2008; Yang and Da 2008; Yu et al. 2009). During recent field surveys in south-eastern Yunnan Province, we collected an unknown Lauraceae species with very large fruits. Further morphological study suggests that this species belongs to Endiandra and differs from its other species distributed in south China and the adjacent regions. As a result, we here describe this species as new to science.

Materials and methods

We conducted field surveys from 2020 to 2022. Morphological characters of the new Endiandra species were examined in detail, based on fresh and preserved materials, as well as dried specimens. We also compared the new species with possible relatives, based on specimens from the herbaria HITBC, IBK, IBSC, KUN, PE, SYS and SZ and images of specimens available on JSTOR Global Plants (www.plants.jstor.org) and GBIF (www.gbif.org).

Results

Taxonomic treatment

Endiandra macrocarpa D.Y.Zou, Lang Li & J.Li, sp. nov.

urn:lsid:ipni.org:names:77317221-1
Figs 1, 2

Diagnosis

Compared to other Endiandra species occurring in south China and the adjacent regions in Indochina, this species is mainly characterised by its much larger ellipsoidal fruits (up to 11 × 6 cm), as well as glabrous branchlets and puberulent inflorescences.

Type

China. Yunnan Province: Maguan County, Gulinqing Town, Houcao Village, in tropical montane forest near the village and is strongly disturbed by human activities, ca. 800 m a.s.l., 12 May 2022, flowering, Lang Li and Dian-yang Zou, 2022028 (Holotype: HITBC!; Isotypes: HITBC!).

Description

Trees evergreen, up to 15 m tall (Fig. 1A). Bark brownish-grey. Branchlets brown, terete, with blunt ridges and striate when dry, glabrous, slightly warty. Leaves alternate; petiole 1–1.5 cm, concave-convex, glabrous; leaf blade greenish and opaque abaxially, green and shiny adaxially, elliptic or oblong-elliptic, 5–16 × 3–7 cm, thinly leathery. Mid-rib elevated on both surfaces, but rather conspicuous abaxially, lateral veins 5–8 pairs, slightly elevated abaxially, conspicuous adaxially, veins and veinlets reticulate, base cuneate to obtuse, mostly asymmetric, apex acuminate with obtuse acumen or obtuse with acute acumen. Panicle axillary, 4–8(10) cm, puberulent (Fig. 1B). Pedicels slender, 1–3 mm, thickened after anthesis. Flowers yellow, scented, ca. 3 mm. Perianth fleshy, unequal, outer ones slightly larger, broadly ovate, 3 × 2 mm (Fig. 2A), adaxially pilose; inner ones smaller, ovate, 2.5 × 1.8 mm, adaxially densely villous (Fig. 2B). Fertile stamens 3, triangular, ca. 2 mm, eglandular, puberulent; anthers thick, stalkless, 2-celled, cells extrorse, tightly adnate to each other; staminodes absent (Fig. 2C, E). Ovary ovoid, ca. 1.2 mm; style short; stigma punctate (Fig. 2D). Fruit ellipsoid or long ellipsoid, up to 11 × 6 cm, immature fruit green, yellow when mature, smooth, glabrous, apex bluntly apiculate (Fig. 1C, D). Seed endocarp light brown with a darker brown network of both broad and fine, slightly raised veins. Fruit stalk brown, up to 5 mm in diam. at apex, glabrous.

Figure 1. 

Morphology of Endiandra macrocarpa A tree habit B flowering branchlet C fruiting branchlet displaying immature fruit D mature fruits. Photographed by Lang Li and Guan-long Cao.

Figure 2. 

Morphology of a flower of Endiandra macrocarpa. A outer tepals, abaxial and adaxial side B inner tepals, abaxial and adaxial side C stamen, abaxial side D pistil E flower, top view F flower, longitudinal section. Photographed by Dian-yang Zou.

Phenology

Flowering from April to May and fruiting from July to October.

Distribution and habitat

Currently known only from the type locality in Maguan County, Yunnan Province, south-western China (Fig. 3). Tropical montane forest in valley, on clay loam soil mixed limestone; ca. 800 m a.s.l.

Figure 3. 

Distribution of E. macrocarpa (black triangle), E. hainanensis (red dot), E. dolichocarpa (green dot) and E. coriacea (yellow dot) in China.

Etymology

The specific epithet “macrocarpa” of the new species refers to its very large fruits compared to the other species within the genus Endiandra.

Preliminary conservation status

Currently, E. macrocarpa is only known from the type locality in Maguan County, Yunnan Province, south-western China with only one mature individual. It is located in tropical montane forest near the village, which is strongly disturbed by human activities. So far, no other occurrence of this species in south-eastern Yunnan and the adjacent regions has been found or reported. Further in-depth field surveys are suggested in order to find more individuals and locations of the species. Thus, the preliminary conservation status of E. macrocarpa is not assessed in the present study.

Additional specimen examined

China. Yunnan Province: Maguan County, Gulinqing Town, Houcao Village, in tropical montane forest near the village, strongly disturbed by human activities, ca. 800 m a.s.l., 26 August 2020, fruiting, Lang Li and Guan-long Cao, 2020158 (HITBC!); 25 April 2021, flowering, Lang Li and Guan-long Cao, 2021029 (HITBC!); 28 October 2021, mature fruits, Lang Li and Dian-yang Zou, 2021081 (HITBC!).

Discussion

South-eastern Yunnan is biogeographically located in a transitional zone from tropical Southeast Asia to subtropical East Asia (Zhu and Yan 2009). The flora of this region is suggested to be a marginal part of the tropical Asian flora, but contains more subtropical and temperate elements than other floras of the adjacent regions, for example, southern Yunnan, south-western Guangxi and northern Vietnam (Zhu and Yan 2009; Zhu 2013). As one of the world’s biodiversity hotspots, south-eastern Yunnan is of extreme interest to botanists not only for its richness of primitive angiosperm taxa, such as species of Lauraceae and Magnoliaceae, but also for being a centre of plant endemism in China (Myers et al. 2000; Zhu and Yan 2009; López-Pujol et al. 2011). A recent study conducted by Zhou et al. (2023) further revealed that south-eastern Yunnan is an endemism centre of Lauraceae with significantly high species richness (SR), phylogenetic diversity (PD), corrected weighted endemism (CWE) and phylogenetic endemism (PE). Recent field surveys in this region also discovered several new endemic species of Lauraceae, for example, Beilschmiedia turbinata Bing Liu & Y. Yang, Caryodaphnopsis malipoensis Bing Liu & Y. Yang, Phoebe hekouensis Bing Liu, W.Y. Jin, L.N. Zhao & Y. Yang and Phoebe jinpingensis Bing Liu, Y. Yang, W.Y.Jin & Zhi Yang (Liu et al. 2013a, b, 2020; Yang et al. 2021).

Far away from its diversity centre in the south-eastern part of Malesia and Australia, Endiandra species are very rare in China. Besides the newly-discovered E. macrocarpa, only three recognised Endiandra species (two endemic) are distributed in Yunnan, Guangxi, Hainan and Taiwan (Li et al. 2008, Fig. 3). Considering the possible endemism of the new species, we firstly compared E. macrocarpa with the other three Endiandra species occurring in China, which possess much smaller fruits (detailed in Table 1). Fruits of E. coriacea Merr. are ovoid, up to 2 × 1 cm. Fruits of E. hainanensis Merr. et F.P. Metcalf ex Allen are narrowly ellipsoid, up to 3.8 × 1.4 cm. Fruits of E. dolichocarpa S. Lee et Y. T. Wei are cylindrical and larger, up to 8 × 2.3 cm, but still much smaller than the fruits of E. macrocarpa. Additionally, E. macrocarpa has glabrous branchlets and puberulent inflorescences, while twigs are puberulent in E. coriacea and panicles are glabrous in E. hainanensis (Li et al. 2008). We also compared E. macrocarpa with three other Endiandra species occurring in the adjacent regions of south-eastern Yunnan in Indochina, for example, Vietnam, Laos and Thailand (detailed in Table 1). Endiandra firma Nees differs from E. macrocarpa by its smaller fruits with rounded tips (Hooker 1875). Endiandra macrophylla (Blume) Boerl. differs from E. macrocarpa by its smaller fruits and much larger leaves (Arifiani 2001). Endiandra rubescens Blume ex Miq. differs from E. macrocarpa by its smaller fruits and pubescent branchlets (Arifiani 2001). Species with giant fruits are uncommon in Endiandra. Endiandra insignis (F.M.Byailey) F.M.Byailey and E. sulavesiana Kosterm., endemic to Australia and Sulawesi, respectively, are the two Endiandra species that possess fruits with comparable size to those of E. macrocarpa (Kostermans 1955; Cussan et al. 2007). However, other fruit characters of these two species are quite different. Endiandra insignis has globular, ribbed fruits (6–8 × 6.5–10.1 cm) and E. sulavesiana has long cylindrical, ribbed fruits (up to 13 × 2.5 cm), while E. macrocarpa has ellipsoidal, smooth fruits (up to 11 × 6 cm). As a result, morphological evidence supports the recognition of E. macrocarpa as a distinct species in the genus Endiandra.

Table 1.
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Comparative morphology, habitat and geographic distribution of Endiandra macrocarpa and its possible relatives.

Morphological character Endiandra macrocarpa Endiandra hainanensis Endiandra dolichocarpa Endiandra coriacea Endiandra firma Endiandra macrophylla Endiandra rubescens
Leaf elliptic or oblong-elliptic, 5–16 × 3–7 cm, thinly leathery, lateral veins 5–8 pairs, petiole 1–1.5 cm, glabrous lanceolate to oblong-elliptic, 9–15 × 3–6 cm, papery, lateral veins 6–8 pairs, petiole 1–1.5 cm, glabrous oblong, 13–25(30) × (4)5–7.5(11) cm, leathery, lateral veins 6–8 pairs, petiole robust, up to 2 cm, glabrous elliptic or obovate, 9–12 × 4.5–6 cm, thickly leathery, lateral veins 5 or 6 pairs, petiole 1–1.2 cm, puberulent initially, but soon glabrate oblong-elliptic, 15–20 × 4 cm, glabrous, lateral veins 10–11 pairs, petiole 1.2 cm elliptic to slightly obovate, 16–30 × 5–13 cm, lateral veins 8–13 pairs, petiole 1.2–2.5 cm, glabrous elliptic, 6.5–15 × 2–7 cm, lateral veins 7–11 pairs, petiole 0.8–1.5 cm, nearly glabrous
Branchlet glabrous glabrous glabrous puberulent – glabrous pubescent
Fruit ellipsoid or long ellipsoid, up to 11 × 6 cm, yellow when mature, glabrous, apex bluntly apiculate narrowly ellipsoid, up to 3.8 × 1.4 cm, purple-brown when mature, glabrous, obtuse at both ends cylindrical when dry, up to 8 × 2.3 cm, black-brown when mature, glabrous, obtuse on both ends ovoid, up to 2 × 1 cm, glabrous, base subrounded, apex acute elliptic-ovoid, up to 6.4 cm long, quite smooth, tip rounded ellipsoid, 4–7.5 × 1.7–2.5 cm, base obtuse ellipsoid, green, 2–5 × 1.3–2.5 cm, base obtuse
Inflorescence axillary, 4–8(10) cm, puberulent axillary, 2–6 cm, few flowered, glabrate – axillary or terminal, up to 8 cm, few flowered, puberulent 2.5–5 cm, obscurely puberulent axillary, 6–15 cm, with a sparse or dense, short, erect indument axillary, 4–13 cm, with a sparse or dense, short, erect indument
Habitat tropical montane forest in valley, on clay loam soil mixed limestone; ca. 800 m mixed forests in valleys, thickets on open land; ca. 400–1100 m forests; ca. 500 m. low hill forests; ca. 20–200 m montane rain forest on sandy loam soil;
ca.100–1800 m		 primary rain forest or peat swamp-forest on clay loam soil or sandy soil; ca. 50–1100 m primary rain forest on sandy loam or acid soils along streams; ca. 20–1500 m
Distribution SW China (Yunnan) S China (Hainan) SW China (Guangxi, Yunnan) SE China (Taiwan), Philippines Bangladesh, India, Vietnam, Malaysia, Indonesia Thailand,Vietnam, Laos, Malaysia, Singapore, Philippines, Indonesia Vietnam, Malaysia, Indonesia, Papua New Guinea, Australia

Note: “–” represents unknown morphological characters.

Acknowledgements

Special thanks to Mr. Xi-bing Guo for his kind help during the field survey. We are also grateful to L. Hurtado and J. G. Rohwer for their valuable suggestions on the manuscript. This work was financially supported by grants from the National Natural Science Foundation of China (No. 31970222) and Yunnan Fundamental Research Projects (No. 202101AT070067).

References

  • Arifiani D (2001) Taxonomic revision of Endiandra (Lauraceae) in Borneo. Blumea 46(1): 99–124.
  • Arifiani D, Basukriadi A, Chikmawati T (2012) The phylogenetic study of new guinean species of Endiandra (Lauraceae) and its relationships with Beilschmiedia based on morphological characters. Floribunda 4(4): 93–102. https://doi.org/10.32556/floribunda.v4i4.2012.96
  • Chanderbali AS, van der Werff H, Renner SS (2001) Phylogeny and Historical Biogeography of Lauraceae: Evidence from the Chloroplast and Nuclear Genomes. Annals of the Missouri Botanical Garden 88(1): 104–134. https://doi.org/10.2307/2666133
  • Kochummen KM (1989) Lauraceae. In: Ng FSP (Ed.) Tree Flora of Malaya, A Manual for Foresters. Longman, Kuala Lumpur 4: 98−144.
  • Kostermans AJGH (1955) Endiandra sulavesiana Kosterm. New Crit. Malaysian Pl. 3: 8.
  • Li SK, Wei FN, Wei YT, Li HW (1979) Materiae ad floram lauracearum sinicarum (III). Acta Phytotaxonomica Sinica 17(2): 45–47.
  • Li HW, Pai PY, Lee SK, Wei FN, Yang YC, Huang PH et al. (1982) Lauraceae. In: Li HW (Ed.) Flora Reipublicae Popularis Sinicae, Vol. 31. Science Press, Beijing, China 3: 1–211.
  • Li HW, Li J, Huang PH, Wei FN, van der Werff H (2008) Lauraceae. In: Wu ZY, Raven PH, Hong DY (Eds) Flora of China, Vol. 7. Science Press, Beijing, China and Missouri Botanical Garden Press, St. Louis, USA.
  • Li HW, Liu B, Davis CC, Yang Y (2020) Plastome phylogenomics, systematics, and divergence time estimation of the Beilschmiedia group (Lauraceae). Molecular Phylogenetics and Evolution 151: 106901. https://doi.org/10.1016/j.ympev.2020.106901
  • Liang CF, Liang JY, Liu LF, Mo XL (1985) A report on the exploration of the flora of Longgang. Guihaia 5(3): 191–209.
  • Liu B, Yang Y, Xie L, Zeng G, Ma KP (2013b) Beilschmiedia turbinata: A newly recognized but dying species of Lauraceae from tropical Asia based on morphological and molecular data. PLoS ONE 8(6): e67636. https://doi.org/10.1371/journal.pone.0067636
  • López-Pujol J, Zhang FM, Sun HQ, Ying TS, Ge S (2011) Centres of plant endemism in China: Places for survival or for speciation Journal of Biogeography. Journal of Biogeography 38(7): 1267–1280. https://doi.org/10.1111/j.1365-2699.2011.02504.x
  • Myers N, Mittermeier RA, Mittermeier CG, da Fonseca GAB, Kent J (2000) Biodiversity hotspots for conservation priorities. Nature 403(6772): 853–858. https://doi.org/10.1038/35002501
  • Richter HG (1981) Anatomie des sekundären Xylems und der Rinde der Lauraceae. Sonderbände des Naturwissenschaftlichen Vereins in Hamburg 5: 1–148.
  • Rohwer JG (2000) Toward a Phylogenetic Classification of the Lauraceae: Evidence from matK Sequences. Systematic Botany 25(1): 60–71. https://doi.org/10.2307/2666673
  • Rohwer JG, Rudolph B (2005) Jumping genera: The phylogenetic positions of Cassytha, Hypodaphnis, and Neocinnamomum (Lauraceae) based on different analyses of trnK intron sequences. Annals of the Missouri Botanical Garden 92(2): 153–178.
  • Rohwer JG, Moraes PL, Rudolph B, van der Werff H (2014) A phylogenetic analysis of the Cryptocarya group (Lauraceae), and relationships of Dahlgrenodendron, Sinopora, Triadodaphne, and Yasunia. Phytotaxa 158(2): 111–132. https://doi.org/10.11646/phytotaxa.158.2.1
  • Song Y, Yu WB, Tan YH, Jin JJ, Wang B, Yang JB, Liu B, Corlett RT (2020) Plastid phylogenomics improve phylogenetic resolution in the Lauraceae. Journal of Systematics and Evolution 58(4): 423–439. https://doi.org/10.1111/jse.12536
  • van der Werff H (2001) An annotated key to the genera of Lauraceae in the flora Malesiana region. Blumea 46: 125–140.
  • van der Werff H, Richter HG (1996) Toward an Improved Classification of Lauraceae. Annals of the Missouri Botanical Garden 83(3): 409–418. https://doi.org/10.2307/2399870
  • Yang Y, Da L (2008) Endiandra R.Br. – A Newly Recorded Genus of Yunnan, China. Acta Botanica Boreali-Occidentalia Sinica 28(6): 1271–1273.
  • Yu ZY, Chen WH, Shui YM (2009) Chrysophyllum and Endiandra, Two Genera New to Yunnan, China. Plant Diversity 31(1): 21–23. https://doi.org/10.3724%20SP.J.1143.2009.08132
  • Zhou R, Ci XQ, Hu JL, Zhang XY, Cao GL, Xiao JH, Liu ZF, Li L, Thornhill AH, Conran JG, Li J (2023) Transitional areas of vegetation as biodiversity hotspots evidenced by multifaceted biodiversity analysis of a dominant group in Chinese evergreen broad-leaved forests. Ecological Indicators 147: 110001. https://doi.org/10.1016/j.ecolind.2023.110001
  • Zhu H, Yan LC (2009) Biogeographical Affinities of the Flora of Southeastern Yunnan, China. Botanical Studies (Taipei, Taiwan) 50: 467–475.
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