[Botany • 2024] Megastigma acarrilloi (Rutaceae) • A New Species from Sinaloa, Mexico, with the northernmost distribution of the genus

Megastigma acarrilloi Pío-León,

in Pío-León, 2024. 

DOI: doi.org/10.21829/abm131.2024.2406 

Abstract

Background and Aims: The genus Megastigma has six described species of shrubs distributed from Colima, Mexico, to Nicaragua. Through a routine review of the iNaturalistMX platform in 2023, a record of an individual of the Megastigma genus was observed, although in a very disjunct locality with respect to known species. The collection and subsequent review of the specimens allowed us to determine that it was a new species for science.

Methods: Botanical explorations and collections were carried out during 2023 and 2024 in the Sierra de Barobampo, municipality of Ahome, Sinaloa, Mexico. The identity of the species was determined by the review of specialized literature. A map with the distribution of each species of the genus was elaborated using the available data in digital repositories and specimens in the MEXU herbarium. The conservation status of the new species was evaluated and proposed according to the IUCN criteria. An identification key is provided for all species of the genus Megastigma.

Results: Megastigma acarrilloi is endemic to northern Sinaloa, Mexico, and has the northernmost distribution of the genus. The species with the closest morphological affinity is M. morenoi, which is endemic to Colima, from which M. acarrilloi differs because it is glabrous and has fewer leaflets per leaf. During the explorations, Lepidopteran larvae of the genus Papilio were observed feeding on its leaves. It is recommended to include M. acarrilloi as a Vulnerable species (VU) on the IUCN Red List.

Conclusions: With the new species, the genus Megastigma is now integrated by seven species, all present in Mexico, and of which six are endemic to the country. Megastigma acarrilloi also represents the first record of the genus for Sinaloa and north of the Trans-Mexican Volcanic Belt.

Keywords: Barobampo mountains, endemism, iNaturalist, iNaturalistMX, Megastigma morenoi, Megastigma skinnerii

Megastigma acarrilloi Pío-León, sp. nov.

Juan Fernando Pío-León. 2024. Megastigma acarrilloi (Rutaceae), A New Species from Sinaloa, Mexico, with the northernmost distribution of the genus.  Acta Botanica Mexicana. 131; DOI: doi.org/10.21829/abm131.2024.2406 

[Botany • 2023] Glycosmis kanburiensis (Rutaceae: Clauseneae) • A New Species from Thailand

Glycosmis kanburiensis  W. Aiyakool & S. Vajrodaya,

in Aiyakool & Vajrodaya, 2023.

เขยตายเมืองกาญจน์  ||  DOI: 10.11110/kjpt.2023.53.1.25

Abstract

Glycosmis kanburiensis (Rutaceae) from Kanchanaburi Province, southwestern Thailand is described as a new species. It is similar to G. esquirolii (H. Lév.) Tanaka in its dendriform habit, terminal inflorescences, and large leaflets, but several easily recognizable differences in floral features, including triangular sepals with rust-colored indumentum (vs. broadly ovate villose sepals), globose, glabrous (vs. subglobose, villosus) ovary, cylindrical and attenuate (vs. stout) style, and ellipsoid (vs. globose) fruit. A taxonomic description, illustration, photographs, geographical distribution, ecological data, and conservation status are provided.

Keywords: Glycosmis, Kanchanaburi, Rutaceae, Taxonomy, Thailand

Illustrations of Glycosmis kanburiensis
A. Flowering branch. B. Flower. C. Androecium. D. Petal. E. Pistil. F. Antisepalous stamen.

 Illustration by W. Aiyakool.

Photographs of Glycosmis kanburiensis
A. Habit. B. Flowering branch. C. Bark of stem. D. Young terminal bud. E. Flower and immature fruit. F. Flower. G. Pistil. H. Androecium. I. Antisepalous stamen. J. Petal. K. Fruit.

Photo A–D and F–K by W. Aiyakool, E by U. Veesommai.

Glycosmis kanburiensis W. Aiyakool & S. Vajrodaya, sp. nov.

Diagnosis: Glycosmis kanburiensis is most similar in morphology to G. esquirolii but differs in having triangular sepals covered with rust-colored indumentum (vs. broadly ovate villose sepals), ovary globose and glabrous (vs. subglobose and villose), style cylindrical and attenuate (vs. stout) and fruit ellipsoid (vs. globose).

Etymology: the specific epithet refers to Kanburi which is a dialectal name of Kanchanaburi Province.

Vernacular name: Khoei Tai Mueang Khan -

 เขยตายเมืองกาญจน์, the name given by us.

ส้มชื่นเมืองกาญจน์

Wichai AIYAKOOL and Srunya VAJRODAYA. 2023. Glycosmis kanburiensis: A New Species of Rutaceae from Thailand. Korean J. Pl. Taxon. 53(1); 25-31. DOI: 10.11110/kjpt.2023.53.1.25

 twitter.com/mio03829/status/1643456989933244416

[Botany • 2023] Ruta museocanariensis • Can Material of A putatively Extinct New Species of Ruta (Rutaceae), preserved with Mummies, provide New Knowledge About Evolution in the Canary Islands Flora?

 

Ruta museocanariensis Marrero Rodr., Vidal Matutano, Delgado Darias & Jaén Molina,   

in Marrero-Rodríguez, Vidal-Matutano, Delgado-Darias, Jaén-Molina, Morales-Mateos, Alberto-Barroso & Velasco-Vázquez, 2023. 

 DOI: 10.3372/wi.53.53101 

Abstract 

Based on analyses carried out with plant material found in mummy shrouds preserved in the archaeological museum El Museo Canario, a putatively extinct new species of Ruta (Rutaceae) was identified and is described here as Ruta museocanariensis. The mummies were found in the funerary sites of Acusa and the Barranco de Guayadeque on Gran Canaria, Canary Islands, Spain. This article discusses taxonomic relationships with other species of the genus, aspects of colonization and evolutionary processes on islands. The archaeological plant material consists of vegetative and reproductive branches with leaves, remains of flowers and capsules. Several morphological traits, especially the type of fruits, establish a clear difference between Ruta species from Gran Canaria and the mainland (dehiscent) and species from the W Canary Islands (indehiscent). The discovery of R. museocanariensis, with dehiscent fruits, suggests that indehiscence is a post-colonization evolutionary process in the Canary Islands. It also supports a stepping-stone model of inter-island colonization with Gran Canaria as its starting point, in agreement with the age of the islands and to some extent with their distance from the mainland.

KEYWORDS: archaeobotany, Canary Islands, El Museo Canario, evolutionary process, extinct new species, mummy shrouds, Ruta, Rutaceae

Ruta museocanariensis 
 A: habit, terminal branch; B: pinna on one side of rachis, adaxial view; C: pedicel, calyx and ovary; D: terminal infructescence twig with open, star-shaped fruit, persistent calyces, bracteoles and immature fruit still closed; E: mature capsules showing dehiscence of valves, basal (left) and apical (right) views. – Image reconstructed from various twigs and fruits in different maturation stages extracted from infant mummy EMC no. 49991 (holotype and isotype) and branches and leaves extracted from adult mummy EMC no. 10 (paratypes).

– Drawn by Á. Marrero.

A: infant mummy EMC no. 49991, from which holotype and isotype specimens of Ruta museocanariensis were extracted;
B: adult mummy EMC no. 10, from the shroud (wrapped in layers of leather) of which the two paratype specimens were extracted;
C: branch bundle EMC no. 46558.

– Photographs by T. Delgado, El Museo Canario.

Ruta museocanariensis Marrero Rodr., Vidal Matutano, Delgado Darias & Jaén Molina, sp. nov. 

Etymology — The specific epithet refers to the scientific entity of El Museo Canario, the institution where the mummies, branch bundle and type specimens are deposited.

Águedo Marrero-Rodríguez, Paloma Vidal-Matutano, Teresa Delgado-Darias, Ruth Jaén-Molina, Jacob Morales-Mateos, Verónica Alberto-Barroso and Javier Velasco-Vázquez. 2023. Can Material of A putatively Extinct New Species of Ruta (Rutaceae), preserved with Mummies, provide New Knowledge About Evolution in the Canary Islands Flora? Willdenowia. 53 (1); 5-23. DOI: 10.3372/wi.53.53101 

[Botany • 2022] Vepris teva (Rutaceae) • Chemistry, Taxonomy and Ecology of the potentially Chimpanzee-dispersed Vepris endangered in Coastal Thicket in the Congo Republic

Vepris teva Cheek,  

in Langat, Kami & Cheek​, 2022. 

 DOI: 10.7717/peerj.13926

Abstract 

Continuing a survey of the chemistry of species of the largely continental African genus Vepris, we investigate a species previously referred to as Vepris sp. 1 of Congo. From the leaves of Vepris sp. 1 we report six compounds. The compounds were three furoquinoline alkaloids, kokusaginine (1), maculine (2), and flindersiamine (3), two acridone alkaloids, arborinine (4) and 1-hydroxy-3-methoxy-10-methylacridone (5), and the triterpenoid, ß-amyrin (6). Compounds 1–4 are commonly isolated from other Vepris species, compound 5 has been reported before once, from Malagasy Vepris pilosa, while this is the first report of ß-amyrin from Vepris. This combination of compounds has never before been reported from any species of Vepris. We test the hypothesis that Vepris sp. 1 is new to science and formally describe it as Vepris teva, unique in the genus in that the trifoliolate leaves are subsessile, with the median petiolule far exceeding the petiole in length. Similar fleshy-leathery four-locular syncarpous fruits are otherwise only known in the genus in Vepris glaberrima (formerly the monotypic genus Oriciopsis Engl.), a potential sister species, but requiring further investigation to confirm this phylogenetic position. We briefly characterise the unusual and poorly documented Atlantic coast equatorial ecosystem, where Vepris teva is restricted to evergreen thicket on white sand, unusual in a genus usually confined to evergreen forest. This endemic-rich ecosystem with a unique amphibian as well as plants, extends along the coastline from the mouth of the Congo River to southern Rio Muni, a distance of about 1,000 km, traversing five countries. We map and illustrate Vepris teva and assess its extinction risk as Endangered (EN B1ab(iii)+B2ab(iii)) using the IUCN, 2012 standard. Only three locations are known, and threats include port and oil refinery construction and associated activities, with only one protected location, the Jane Goodall Institute’s Tchimpounga Reserve. Initial evidence indicates that the seeds of Vepris teva are dispersed by chimpanzees, previously unreported in the genus.

Vepris teva Cheek sp. nov.
Shrub with mature (yellow) and immature (green) fruits. Note the sessile leaves.

From Mpandzou et al., 1198 (IEC, K). 

Photo by M. Cheek.

Vepris teva Cheek sp. nov.
 (A) Habit, fruiting stem; (B) detail of leaflet blade showing oil gland dots and nervation, lower surface of blade in foreground; (C) detail of male inflorescence; (D) male flower, side view; (E) as (D), two petals removed to show stamens; (F) pistil of male flower, four-lobed, viewed from above; (G) male flower, two petals and three stamens removed to show pistil; (H) mature fruit, side view (seed on right); (I) fruit, plan view; (J) fruit, transverse section, showing four locules, three aborted and one with seed.

(A and H–J) from Mpandzou et al., 1198, (B and G) from Kami, T. et al 1356; (C–F) from Kami, T. et al., 1227. 

Drawn by Juliet Williamson, CC-BY-NC-ND.

Vepris teva Cheek sp. nov.

Diagnosis: differs from all known trifoliolate species of Vepris in the median petiolule far exceeding the petiole in length (usually by a factor of 2–4 times) on reproductive stems, especially near the stem apex (vs petiole exceeding petiolule in length in all other species). Most similar to Vepris glaberrima (Engl.) J.B.Hall ex D.J. Harris in the soft, leathery-fleshy, four-loculed, and slightly lobed, subverrucate syncarpous fruit, differing in the inflorescences exceeding the petiole in length (vs shorter than the petioles), the secondary nerves (10–)11–16(–18) on each side of the midrib (vs 20–30), the leaflet apices shortly rounded-acuminate (vs long, acutely acuminate) and other characters shown in Table 1 above.

Etymology. Named for Teva Kami, lead collector of the type specimen, who played a key role in the discovery of this species and further research upon it concerning interactions with chimpanzees (see below).

 

Moses K. Langat, Teva Kami and Martin Cheek​. 2022. Chemistry, Taxonomy and Ecology of the potentially Chimpanzee-dispersed Vepris teva sp.nov. (Rutaceae) endangered in Coastal Thicket in the Congo Republic.  PeerJ. 10:e13926. DOI: 10.7717/peerj.13926

 

[Botany • 2021] Luvunga subanense (Rutaceae) • A New Species from Mindanao, southern Philippines

Luvunga subanense K.R. Mazo & Tahil,

in Mazo & Tahil, 2021. 

DOI: 10.3100/hpib.v26iss2.2021.n7 

 huh.harvard.edu

  twitter.com/Kean_Roe 

 Abstract

 After 113 years since the only Luvunga species was described from the Philippines and after 36 years since the latest species of the genus was formally described from Sabah, Borneo, a species new to science of Luvunga from Zamboanga del Norte, Southern Philippines, L. subanense, is described and illustrated. The new species differs from similar species, L. philippinensis and L. crassifolia, by having longer thorns, longer petioles and an inflorescence of four-flowered cymes. It further distinguishes from its most similar species, L. philippinensis, by having nine stamens (vs. 10), shorter filaments (4–4.5 mm vs. 6 mm) and ovoid ovary (vs. oblong) which is globular in cross-section (vs. quadrangular). Figures, a table of comparing the new species to L. philippinensis and L. crassifolia, notes on distribution, habitat and conservation status are provided. This novelty brings the total number of Luvunga species to 15 of which four are found in the Philippines. 

Keywords: Luvunga philippinensis, Mindanao, morphology, Rutaceae, taxonomy, Zamboanga

Luvunga subanense K.R. Mazo & Tahil, sp. nov.

A similar species to both L. philippinensis Merr. and L. crassifolia Tan. by having generally oblongate leaflets and pubescent filaments, but differing in the length of thorns (2.5–3.0 vs. 1.2–1.5 vs. 2.0–2.5 cm) and petioles (14–24 vs. 9–13 vs. 11–14.5 cm) and the number of flower being produced in each cyme (4 vs. 3 vs. 6). It is further distinguished from a much closer species, L. philippinensis, by having nine stamens (vs. 10), shorter filaments (4–4.5 vs. 6 mm) and ovoid ovary (vs. oblong) which is globular in cross-section (vs. quadrangular).

Etymology: This taxonomic novelty is named in honor of the indigenous Subanen people of Zamboanga Peninsula. 

Distribution and habitat: Luvunga subanense is only known in the disturbed tropical lowland forest of barangay Tinuyop, Leon B. Postigo, Zamboanga del Norte, the Philippines along the river at elevation from 300–330 m elevation.

Kean Roe F. Mazo and Arkady A. Tahil. 2021. Historic Discovery of A New Species of Luvunga (Rutaceae) from Mindanao, southern Philippines. Harvard Papers in Botany. 26(2); 427–431. DOI: 10.3100/hpib.v26iss2.2021.n7 

 huh.harvard.edu/pdf-downloads

  twitter.com/Kean_Roe/status/1517697104063655936

[Botany • 2021] Glycosmis albicarpa (Rutaceae: Clauseneae) • A New Species from southern Western Ghats, India

  Glycosmis albicarpa Sujana & Vadhyar, 

 

in Sujana & Vadhyar, 2022. 

 DOI: 10.1111/njb.03501

 

Abstract

A new species, Glycosmis albicarpa Sujana & Vadhyar from Kanyakumari wildlife sanctuary of southern Western Ghats, India is described and illustrated. It differs from all other species of Glycosmis by its short and broadly lanceolate leaves, short (3–5 mm long) peduncles, clawed petals and broadly ovoid white fruits. The description is complemented with color photographs, micromorphology of pollen and seed under SEM.

Keywords: endemic, Kanyakumari wildlife sanctuary, micromorphology, pollen, SEM

Kanjiraparambil Arjunan Sujana and Rakesh G. Vadhyar. 2022. Glycosmis albicarpa (Rutaceae: Clauseneae), A New Species from southern Western Ghats, India. Nordic Journal of Botany. DOI: 10.1111/njb.03501

[Botany • 2018] Haplophyllum ermenekense (Rutaceae) • A New Species from Turkey

Haplophyllum ermenekense Ulukuş & Tugay

in Ulukuş & Tugay, 2018.

 DOI: 10.3897/phytokeys.111.24241 

Abstract

A new species of Haplophyllum, Haplophyllum ermenekense (Rutaceae) is described and illustrated in line drawing. It grows on stony slopes of Ermenek town, Karaman province, in southern Turkey. It is compared with the closely related species H. myrtifolium. H. ermenekense is distinguished from the morphologically similar H. myrtifolium chiefly by sepal shape, petal size, capsule size, presence of capsule hair and appendage form. On the other hand, the seed coat and pollen grains surface of H. ermenekense and H. myrtifolium are demonstrated in SEM photographs. In addition to the detailed description, the illustration, distribution map, conservation status and ecology of the new species are also provided.

Keywords: Endemic, Haplophyllum, Karaman, Rutaceae, taxonomy

Figure 2. Line drawing of Haplophyllum ermenekense.
A habit B petal of H. ermenekense C petal of H. myrtifolium D calyx of H. ermenekense E calyx of H. myrtifolium F stamen of H. myrtifolium G stamen H. ermenekense H capsule of H. myrtifolium I capsule of H. ermenekense J flower of H. ermenekense (Drawn from the holotype by O.Tugay).

Figure 3. General view of habit and flowers: A, B Haplophyllum ermenekense C, D H. myrtifolium.

Haplophyllum ermenekense Ulukuş & Tugay, sp. nov.

Diagnosis: Haplophyllum ermenekense most resembles the closely related H. myrtifolium. It differs from H. myrtifolium by its inflorescence usually lax form (versus dense), sepals ovate or ovate-oblong (versus lanceolate or lanceolate-oblong) and deciduous in fruit (versus persistent in fruit), petals 4–5.5 × 1.5–2.5 mm (versus 6.5–9.5 × 3.5–4.5 mm), capsule 2–2.5 × 3–4 mm (versus 3–3.5 × 5–6 mm) and glabrous (in contrast to not glabrous), with a conspicuous usually erect appendage on the outer upper surface (versus incurved appendage on the outer upper portion).

Etymology: The name of Ermenek town where new species found is given to the species epithet.

Proposed Turkish name for the new species: Ermenek sedosu.

Ecology: Haplophyllum ermenekense is endemic to Turkey. It grows at altitudes between 980 and 1200 m on limestone slopes amongst bushes (e.g. Quercus coccifera L., Juniperus oxycedrus L., Pistacia terrebinthus M.Bieb. etc.). Plant diversity in this place is mainly composed of herbaceous and suffruticose plants including Adonis flammea Jacq., Aegilops cylindrica Host, Aethionema stylosum DC., Capsella bursa-pastoris (L.) Medik., Centaurea virgata Lam., Digitalis cariensis Boiss. ex Jaub. & Spach, Ebenus plumosa Boiss. & Bal. subsp. speciosa Boiss.& Bal., Glaucium corniculatum (L.) Rud. subsp. corniculatum, Glaucium leiocarpum Boiss., Hyoscyamus aureus L., Hyoscyamus niger L., Isatis ermenekense Yıld., Micromeria cristata (Hampe) Griseb. subsp. cristata, Salvia albimaculata Hedge & Hub-Mor. and Salvia aucheri Bentham var. canescens Boiss. & Heldr.

Distribution and conservation status: Haplophyllum ermenekense is endemic to Karaman province. It is an element belonging to the east Mediterranean phytogeographic region (Fig. 1). The range of this new species is limited to a single locality and its area of occupancy is estimated to be less than 5 km or 5 km2. The number of mature individual plants is estimated to be less than 250. As it is perennial, this new species has a crucial advantage for its future as destruction of the bushes by local people, road construction and deterioration of habitats may cause some threats. Thus, according to criterion D, it can be included in the EN (Endangered) category (IUCN 2001; 2016).

 Deniz Ulukuş and Osman Tugay. 2018. Haplophyllum ermenekense (Rutaceae), A New Species from Turkey.  PhytoKeys. 111: 119-131. DOI: 10.3897/phytokeys.111.24241

   

[Botany • 2018] Vepris bali (Rutaceae) • A New Critically Endangered (possibly Extinct) Cloud Forest Tree Species from Bali Ngemba, Cameroon

Vepris bali Cheek

in Cheek, Gosline & Onana, 2018

  DOI:  10.3372/wi.48.48207 

Abstract 

Vepris bali is the first known species of Vepris in WC Africa with opposite, trifoliolate leaves and is further unusual for its long petiolules. Known only from Bali Ngemba Forest Reserve, a remnant of submontane forest under great pressure of degradation in the Bamenda Highlands of Cameroon, it may already be extinct due to tree cutting and agricultural incursions. Here, V. bali is compared with other endemic cloud forest Vepris of the Cameroon Highlands and is described, illustrated, mapped and assessed as Critically Endangered (Possibly Extinct) using IUCN 2012 criteria.

Fig. 1. Vepris bali. A: habit, flowering stem with male inflorescence; B: stem detail showing indumentum and lenticels; C: abaxial leaf surface showing oil glands; D: portion of partial-inflorescence showing bracts; E: male flower, side view; F: male flower, 2 sepals and petals removed and staminal filaments truncated; G: cross-section of rudimentary pistil.

 Drawn from the holotype, Ujor FHI 30422 (K), by Hazel Wilks.

Vepris bali Cheek, sp. nov. 

– Toddaliopsis ebolowensis sensu Letouzey (1963: 108), non Engl. (1917: 305).

– Vepris cf. heterophylla sensu Mziray (1992: 73), non (Engl.) Letouzey (1966: 246).

– “Vepris sp. B” Cheek in Harvey & al. (2004: 55 [fig. 7], 124); Onana & Cheek (2011: 309).

Diagnosis — Differing from Vepris ebolowensis (Engl.) Onana in being a submontane tree, with a trunk c. 28 cm in diam, at 1.5 m from ground, leaves opposite, and median petiolules 9–14 mm long (whereas V. ebolowensis is a shrub of lowland forest, with leaves alternate, and median petiolules c. 0 mm long).

Holotype: Cameroon, Northwest Region, “Bamenda District, Bali-Ngemba Forest Reserve, in high forest on ... at the height of  1700 m. alt. with Uapaca sp., Garcinia sp., and Aningeria”, male fl., Mar 1951, Ujor FHI 30422 (K; isotype: FHI n.v.).

....

Etymology — The specific epithet is a noun in apposition, from the town and people of Bali in the Bamenda Highlands of the Northwest Region of Cameroon, near which, in the Bali Ngemba Forest Reserve, the only known locality for this tree is found.

Martin Cheek, George Gosline and Jean-Michel Onana. 2018. Vepris bali (Rutaceae), A New Critically Endangered (possibly Extinct) Cloud Forest Tree Species from Bali Ngemba, Cameroon. Willdenowia. 48(2); 285-292. DOI:  10.3372/wi.48.48207

New Tree Species Discovered — and Declared Extinct   therevelator.org/tree-discovered-extinct/

[Botany • 2018] Genomics of the Origin and Evolution of Citrus

Proposed origin of Citrus and ancient dispersal routes. Arrows suggest plausible migration directions of the ancestral citrus species from the centre of origin—the triangle formed by northeastern India, northern Myanmar and northwestern Yunnan. The proposal is compatible with citrus biogeography, phylogenetic relationships, the inferred timing of diversification and the paleogeography of the region, especially the geological history of Wallacea and Japan. The red star marks the fossil location of C. linczangensis. Citrus fruit images in c and d are not drawn to scale.

Wu, Terol, Ibanez, et al., 2018. 

   DOI: 10.1038/nature25447

Abstract

The genus Citrus, comprising some of the most widely cultivated fruit crops worldwide, includes an uncertain number of species. Here we describe ten natural citrus species, using genomic, phylogenetic and biogeographic analyses of 60 accessions representing diverse citrus germ plasms, and propose that citrus diversified during the late Miocene epoch through a rapid southeast Asian radiation that correlates with a marked weakening of the monsoons. A second radiation enabled by migration across the Wallace line gave rise to the Australian limes in the early Pliocene epoch. Further identification and analyses of hybrids and admixed genomes provides insights into the genealogy of major commercial cultivars of citrus. Among mandarins and sweet orange, we find an extensive network of relatedness that illuminates the domestication of these groups. Widespread pummelo admixture among these mandarins and its correlation with fruit size and acidity suggests a plausible role of pummelo introgression in the selection of palatable mandarins. This work provides a new evolutionary framework for the genus Citrus.

Figure 1: Genetic structure, heterozygosity and phylogeny of Citrus species.  a, Principal coordinate analysis of 58 citrus accessions based on pairwise nuclear genome distances and metric multidimensional scaling. The first two axes separate the three main citrus groups (citrons, pummelos and mandarins) with interspecific hybrids (oranges, grapefruit, lemon and limes) situated at intermediate positions relative to their parental genotypes. b, Violin plots of the heterozygosity distribution in 58 citrus accessions, representing 10 taxonomic groups as well as 2 related genera, Poncirus (Poncirus trifoliata, also known as Citrus trifoliata) and Chinese box orange (Severinia). White dot, median; bar limits, upper and lower quartiles; whiskers, 1.5× interquartile range. The bimodal separation of intraspecies (light blue) and interspecies (light pink) genetic diversity is manifested among the admixed mandarins and across different genotypes including interspecific hybrids. Three-letter codes are listed in parenthesis with additional descriptions in Supplementary Table 2. c, Chronogram of citrus speciation. Two distinct and temporally well-separated phases of species radiation are apparent, with the southeast Asian citrus radiation followed by the Australian citrus diversification. Age calibration is based on the citrus fossil C. linczangensis16 from the Late Miocene (denoted by a filled red circle). The 95% confidence intervals are derived from 200 bootstraps. Bayesian posterior probability is 1.0 for all nodes. d, Proposed origin of citrus and ancient dispersal routes. Arrows suggest plausible migration directions of the ancestral citrus species from the centre of origin—the triangle formed by northeastern India, northern Myanmar and northwestern Yunnan. The proposal is compatible with citrus biogeography, phylogenetic relationships, the inferred timing of diversification and the paleogeography of the region, especially the geological history of Wallacea and Japan. The red star marks the fossil location of C. linczangensis. Citrus fruit images in c and d are not drawn to scale.

Guohong Albert Wu, Javier Terol, Victoria Ibanez, Antonio López-García, Estela Pérez-Román, Carles Borredá, Concha Domingo, Francisco R. Tadeo, Jose Carbonell-Caballero, Roberto Alonso, Franck Curk, Dongliang Du, Patrick Ollitrault, Mikeal L. Roose, Joaquin Dopazo, Frederick G. Gmitter, Daniel S. Rokhsar and Manuel Talon. 2018. Genomics of the Origin and Evolution of Citrus.  Nature.   DOI: 10.1038/nature25447

  

The Citrus Family Tree  on.natgeo.com/2AQGWMo   @NatGeoMag

  

[Botany • 2017] Melicope stonei section Pelea (Rutaceae) • A New Species from Kaua‘i, Hawaiian Islands: with Notes on Its Distribution, Ecology, Conservation Status, and Phylogenetic Placement

Melicope stonei K.R. Wood, Appelhans & W.L. Wagner

 DOI:  10.3897/phytokeys.83.13442 

Abstract

Melicope stonei K.R. Wood, Appelhans & W.L. Wagner (section Pelea, Rutaceae), a new endemic tree species from Kaua‘i, Hawaiian Islands, is described and illustrated with notes on its distribution, ecology, conservation status, and phylogenetic placement. The new species differs from its Hawaiian congeners by its unique combination of distinct carpels and ramiflorous inflorescences arising on stems below the leaves; plants monoecious; leaf blades (5–)8–30 × (4–)6–11 cm, with abaxial surface densely tomentose, especially along midribs; and very long petioles of up to 9 cm. Since its discovery in 1988, 94 individuals have been documented and are confined to a 1.5 km2 region of unique high canopy mesic forest. Melicope stonei represents a new Critically Endangered (CR) single island endemic species on Kaua‘i.

Keywords: Rutaceae, Melicope, M. section Pelea, new species, conservation, Hawaiian Islands, Kaua‘i, Critically Endangered

Among the most striking characters of Melicope stonei are the ramiflorous inflorescences, meaning that the flowers spring directly from the branches below the leaves.

photo: Kenneth R. Wood

Figure 1. Melicope stonei  K.R. Wood, Appelhans & W.L. Wagner.
A Flowering branch B Adaxial leaf surface near margin toward apex C Abaxial leaf surface near margin toward apex D Ramiflorous inflorescence arising below leaves on stem E Female flower, lateral view F Immature fruit and flowers G Dehisced fruit, showing seeds.

 A-C from Wagner & Wood 6891 (US) D from Wood 8431 (US) E from Wood 15101 (PTBG) F from Wood & Lee 16729 (photo) G from Lorence et al. 6454 (photo) (Illustration by Alice Tangerini).

Melicope stonei K.R.Wood, Appelhans & W.L.Wagner, sp. nov.

Diagnosis: Differs from Hawaiian congeners by its combination of distinct carpels and ramiflorous inflorescence; plants monoecious; leaf blades (5–)8–30 × (4–)6–11 cm, with abaxial surface tomentose, especially along midribs; and very long petioles of up to 9 cm.

Etymology: We are pleased to name Melicope stonei in honor of Benjamin Clemens Masterman Stone, British-American botanist, born in Shanghai, China in 1933 and passed in 1994 while working at the Philippine National Museum on the Flora of the Philippines Project. He contributed over 300 publications to science during his career, including taxonomic monographs of Hawaiian Pelea (Stone 1969) and Platydesma (Stone 1962). For all his contributions, especially his keen insights into Hawaiian Melicope, we gratefully extend him due recognition.

....

 Kenneth R. Wood, Marc S. Appelhans and Warren L. Wagner. 2017. Melicope stonei, section Pelea (Rutaceae), A New Species from Kaua‘i, Hawaiian Islands: with Notes on Its Distribution, Ecology, Conservation Status, and Phylogenetic Placement.
  PhytoKeys. 83: 119-132.  DOI:  10.3897/phytokeys.83.13442

A new critically endangered tree species depends on unique habitat found only on Kaua'i  phy.so/422107940 @physorg_com

A new critically endangered tree species depends on unique habitat found only on Kaua'i  blog.pensoft.net/2017/08/16/a-new-critically-endangered-tree-species-depends-on-unique-habitat-found-only-on-kauai/