Journal of Threatened Taxa | www.threatenedtaxa.org | 26 June 2020 | 12(9): 16064–16076

 

ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print) 

doi: https://doi.org/10.11609/jott.5004.12.9.16064-16076

#5004 | Received 12 April 2019 | Final received 11 May 2020 | Finally accepted 06 June 2020

 

 

Resolving taxonomic problems in the genus Ceropegia L. (Apocynaceae: Asclepiadoideae) with vegetative micromorphology

 

Savita Sanjaykumar Rahangdale 1  & Sanjaykumar Ramlal Rahangdale 2

 

1 Department of Botany, B.J. College, Ale, Pune District, Maharashtra 412411, India.

2 Department of Botany, A.W. College, Otur, Pune District, Maharashtra 412409, India.

1 gauriyana@yahoo.co.in, 2 rsanjay2@hotmail.com (corresponding author)

 

 

Editor: M.K. Vasudeva Rao, Shiv Ranjani Housing Society, Pune, India.   Date of publication: 26 June 2020 (online & print)

 

Citation: Rahangdale, S.S. & S.R. Rahangdale (2020). Resolving taxonomic problems in the genus Ceropegia L. (Apocynaceae: Asclepiadoideae) with vegetative micromorphology.  Journal of Threatened Taxa 12(9): 16064–16076. https://doi.org/10.11609/jott.5004.12.9.16064-16076

 

Copyright: © Rahangdale & Rahangdale 2020. Creative Commons Attribution 4.0 International License.  JoTT allows unrestricted use, reproduction, and distribution of this article in any medium by providing adequate credit to the author(s) and the source of publication.

 

Funding: Self-funded.

 

Competing interests: The authors declare no competing interests.

 

Author details: Savita S. Rahangdale is presently Assistant Professor in Botany with an experience of 20 years in teaching and research. Her major research areas are Angiosperm taxonomy and medicinal plants.  Sanjaykumar R. Rahangdale is Associate Professor in Botany. His research interests are, cytology, genetics, taxonomy and ecosystem conservation. Both are associated with State Department of Forests as Honorary Botanists towards diversity and conservation studies.

 

Author contribution: SSR has done the micro-morphology work of this study and presentation of the results. SRR has done the field work, collection and processing of samples, morphological characterization of the taxa, photography and manuscript editing. The work is done on a mutual benefit basis.

 

Acknowledgements: Authors are thankful to the authorities of BSI, Pune and ARI Pune for herbarium references.  The thanks are due to Dr. Aniket Gade, Department of Biotechnology, SGBAU, Amravati for cladistics analysis and help.  The authorities of respective institutions of authors are sincerely acknowledged for facilities & support.

 

 

Abstract: The genus Ceropegia L. of Family Apocynaceae, subfamily Asclepiadoideae comprises 213 accepted taxa distributed in tropical and sub-tropical regions of Africa, India, Australia and neighbouring regions. The taxa are mainly identified on the basis of flower morphology. A study was undertaken to reveal micromorphology of 26 taxa distributed in Western Ghats of India to solve the identity problems. The micromorphology is studied with standard microscopic methods in five replicates of each character and taxa to reveal the parameters, distribution of stomata, stomatal index, stomatal density, epidermal cell wall pattern and stomatal measurements. The data obtained was subjected to ANOVA to find out the experimental mean, standard deviation and standard error. A consensus phylogeny tree is constructed using the PAST on the basis of Jaccard similarity coefficient. Results of study revealed that, micro morphological characters, viz., type of stomata, number and characters of subsidiaries, anticlinal cell wall pattern, and stomatal index are very significant in delimitation of closely allied taxa. Beside ‘paracytic’ stomata, ‘tetracytic’, ‘isotricytic’, & ‘anomocytic’ stomatal types, and amphistomatic distribution are recorded for first time in Ceropegia. The taxa are separated easily from each other using vegetative micromorphology and can be identified even in absence of flowers. An identification key and phylogenetic tree is derived on the basis of vegetative micro-morphology and gross morphological characters.

 

Keywords: Epidermal cell wall pattern, identification key, phylogeny, stomata, stomatal index, subsidiaries.

 

Abbreviations: SD—Stomatal density | SI—Stomatal index | WG—Western Ghats.

 

 

 

 

INTRODUCTION

 

The genus Ceropegia L. of family Apocynaceae, subfamily Asclepiadoideae comprises many narrow endemic and threatened species distributed only in tropical and sub-tropical regions especially, Africa, India, Australia, and neighbouring region.  The genus comprises of 213 accepted species, eight unplaced, and 36 un-assessed taxa of species and infra-specific ranks (Plant list 2019; Plant of the World Online 2020).  Most of the taxa are endemic to the regions or locations from where they are described.  In India, it is represented by about 68 taxa comprising of 61 species, two subspecies and five varieties with recent descriptions by Diwakar & Singh (2011), Rahangdale & Rahangdale (2012), Kamble et al. (2012), Sujanapal et al. (2013), and Kumar et al. (2018).  Of these taxa, 40 species and six varieties are endemic to India, while 34 species and two varieties are endemic to Western Ghats (Jagtap & Singh 1999; Singh et al. 2015).

The taxa under this genus are mainly described on the basis of floral characters, while many vegetative characteristics are similar in many taxa.  The taxonomists in the world have tried to resolve systematic crises among these species or taxa below rank of species.  Since last decade many new taxa at specific and infra-specific rank are described (Singh et al. 2015).  Still, many of the Indian taxa are kept under unresolved categories by international databases (such as The Plant List (2019) as well as POWO  (2020)) due to insufficient data related to allied species and varieties.  In India, there are two major regions of distribution of this genus, viz., Himalaya and peninsular India.  Most species found in Western Ghats or peninsular India possess tubers, while those found in the Himalayan region do not have tubers and are non-succulent.  In general, all these taxa are described on the basis of morphological characters; especially on floral morphology as the allied taxa do have many similarities in vegetative characters.  The vegetative micro-morphology was neglected in most of the cases, may be because of morpho-similarities among the taxa in vegetative condition.  There is negligible literature available on microscopic characters of vegetative organs; and Ceropegia species are generally identified on the basis of habit and flower characters.  Therefore, it is a difficult task to identify the species without flowers.  So, there is need of micro-morphological as well as anatomical characters that would be helpful in identification of taxa at species and infra-specific level in vegetative state.  Considering these facts and lacunae in the literature a study was undertaken to reveal micro-morphological characters of taxa of this genus and provide identification key on the basis of vegetative and micro-morphological characters.

 

 

MATERIALS AND METHODS

 

Plant Materials

Materials for the present study comprise a total 26 taxa of the genus Ceropegia L. from Western Ghats.  Fresh materials were collected from wild plants as well as plants maintained in the nursery for study.  The locations of taxa included in the study range from Nashik in Maharashtra to Coimbatore in Tamil Nadu through Wayanad in Kerala.  A list of taxa under study with their status, distribution, and locations of collection for the present study is given in the Table 1.

In the present study, C. attenuata Hook. var. attenuata, C. attenuata Hook. var. mookambikae Diwakar & Singh, C. mahabalei Hemadri & Ansari var. hemalatae Rahangdale & Rahangdale, C. mahabalei Hemadri & Ansari var. mahabalei, C. maharashtrensis Punekar et al. are retained because these taxa are merged without any solid reasons and without comparing the characters said in original protologues of above mentioned taxa. As the present study is aimed to find out more stable characters for correct distinction between the taxa, the above mentioned taxa are accepted.

 

Methods

Vegetative morphology

Total 14 vegetative morphological characters of each taxon are recorded by observation of living materials.  They are mentioned in the Table 4 to avoid repetition.  Only newly observed characters are mentioned in detail.

 

Micro-morphology

For epidermal study, five leaves per sample were picked at 4–6th nodes from base.  Epidermal peelings of suitable size were made from both upper and lower surfaces of each leaf.  Peelings were treated with 5% Sodium Hypochlorite for clearing.  Then epidermal debris was brushed off under observation using Lawrence and Mayo stereo-zoom microscope NSZ-606 and the peel was finally mounted in 50% Glycerine.  Thereafter, slides were observed under research microscope (Lawrence & Mayo Model No. XSZ-N107T) for epidermal details.  For this, five leaves were taken and from each leaf five different fields were observed and data was recorded, making total observation size of 25 sample areas.  The observed parameters are, type of stomata, distribution of stomata on leaf surface (hypostomatic/amphistomatic), stomatal density/mm2, stomatal Length (µ), Width (µ), pore length (µ), characters and number of subsidiaries and epidermal cell wall characters as per the techniques described by Dilcher (1974) and Kotresha & Seetharam (2000).  The classification of stomatal types given by Prabhakar (2004) was followed to recognize stomatal complex, with number and characteristics of subsidiaries.

 

Parameters studied

1.              Stomatal index (SI):

Stomatal index = [S ÷ (E+S)] × 100

where, E = no. of epidermal cells, S = no. of stomata in an unit (mm2) area taken for observation (0.022mm2 under 400X magnification).

2.              Stomatal Density (SD):

Stomatal Density = No. of stomata per unit area (1mm2)

For this, number of stomata in a unit area is recorded for total sample size as that for stomatal index observations.

3.              Stomatal length (μ):

The length of stomata is measured as the longitudinal end to end distance of guard cells, using ocular meter scale standardized for each magnification with the stage micrometer.

4.              Stomatal width (μ):

This is the maximum length in the middle transect of stoma with the ocular meter scale.

5.              Stomatal pore length (μ):

This is length of stomatal opening observed with the help of ocular meter scale.

Statistical analysis comprising of mean, variance, standard deviation, and standard error are applied for each parameter as per method given by Singh & Chaudhary (1985).

 

Phylogenetic analysis

Phylogenetic analysis was done on the basis of 42 vegetative morphological and micro-morphological characters (Table 4).  For phylogenetic analysis PAST ver.03 was used as per Harper (1999), Hammer et al. (2001), Hammer & Harper (2006).  In this, the characters were represented in the binary format (Table 5), which was used to generate a phylogenetic tree by Jaccard similarity coefficient model and data replication method - bootstrap method at 1,000 replications on the basis of a matrix of characters.

 

 

RESULTS

 

The observations regarding stomatal distribution, type, subsidiaries character & number, and the anticlinal wall characters of epidermal cells are presented in the Table 2 and Image 1.  The results are described under the subheads as mentioned below.

 

Distribution and type of stomata

The stomata are distributed only on lower surface of the leaf (hypostomatic) in all the taxa studied except in C. bulbosa.  In both varieties, C. bulbosa var. bulbosa and C. bulbosa var. lushii, the leaves are amphistomatic, i.e., stomata are present on both surfaces of the leaves.  Four types of stomata, i.e., paracytic, anomocytic, tetracytic, and isotricytic are recorded in the taxa under study.  Among these types, the paracytic stomata are most common and found in 16 taxa, the anomocytic are less common and recorded in four taxa; while the tetracytic stomata are observed in only C. elegans.  Five taxa have mixed stomata; of which, four taxa viz., C. anantii, C. attenuata var. attenuata, C. maharashtrensis, and C. sahyadrica have isotricytic and tetracytic intermixed with each other, while in C. rollae paracytic stomata were found along with anomocytic stomata.

 

Characters and number of subsidiaries

The subsidiaries in studied taxa are either distinct (different than epidermal cells) or indistinct (same as epidermal cells).  The stomatal complexes in 12 taxa have distinct subsidiaries while 13 taxa have indistinct ones.  Among the 16 taxa having paracytic stomata, 12 taxa have distinct subsidiaries while remaining four have indistinct ones.  In C. rollae, where stomata are of mixed type, i.e., paracytic and anomocytic, the subsidiaries were distinct along the paracytic stomata while with anomocytic stomata there were indistinct subsidiaries.  The number of subsidiaries is also variable from two to five, but generally showed a fixed number or a range in all the specimens of same taxon.  The number is fixed to two subsidiaries in nine taxa and four subsidiaries in two taxa.  In other 15 taxa, the number of subsidiaries ranges 2–3 in three taxa, 2–4 in three taxa, 3–4 in seven taxa, and 4–5 subsidiaries in two taxa with anomocytic stomata.  The taxa having mixed stomata with isotricytic and tetracytic types have indistinct subsidiaries.

 

Anticlinal wall pattern

The patterns of anticlinal walls of epidermal cells are observed and recorded in all the taxa under study.  There are three patterns, ‘straight’, ‘rounded (curved)’, and ‘undulate (wavy)’.  Out of all 26 taxa, 10 have undulate anticlinal walls, eight taxa have rounded walls, and remaining eight have straight anticlinal walls.  The results showed that, anticlinal wall pattern is not found to be associated with the other characters studied.  This character is independent of stomatal type, size or number and type of subsidiaries.  But, it is important for the differentiation between different taxa.

  

Stomatal characteristics

The experimental results about stomatal measurements are presented in Table 3 and described below.

 

Stomatal Index (SI)

The results revealed that, mean value of SI for the taxa under study (experimental mean) is 14.75±0.35.  The highest SI is found in C. attenuata var. attenuata (21.80) followed by C. mahabalei var. hemalatae (20.32), and C. sahyadrica (19.94); while the lowest value of SI is recorded in C. juncea (8.18) along with C. panchganiensis (11.24), C. vincifolia (11.81), and C. hirsuta (11.88).

 

Stomatal Density (SD)

The mean value for stomatal density/mm2 of leaf area is 252.31±8.50 with the highest value of 403.64±10.60 in C. maharashtrensis followed by C. anantii (390.91), and C. jainii (370.91), while the lowest SD 98.18±3.40 in C. juncea subtended by C. bulbosa var. lushii (105.45), C. bulbosa var. bulbosa (127.27), and C. hirsuta (152.73).  C. juncea is a succulent taxon with highly reduced leaves and also have lowest value of SI.

 

Stomatal Size

Regarding the stomatal dimensions, the largest stomata are recorded in Ceropegia juncea, while the smallest stomata in the C. attenuata var. mookambikae.  The experimental mean for stomatal length is 29.54±0.73µ, stomatal width 19.68±0.67µ and the pore length 19.68±0.64 microns.  The stomatal length is highest in C. juncea (39.0µ), followed by C. vincifolia (32.5µ), C. bulbosa (32.25µ), C. oculata (32.0µ), and C. candelabrum (31.5µ).  The succulent species C. juncea have largest stomata with respect to length 39.0±1.5µ, width 26.5±1.7µ, and pore length 27.0±0.97µ; while those values for C. attenuata var. mookambikae are 23.0±0.5µ, 15.0±0.79µ, and 12.0±0.5µ, respectively having the smallest stomata.  As per the ratio of length x width, the stomatal size is ranging from the smallest one of 345µ2 in C. attenuata var. mookambikae to 1033.5µ2 in C. juncea has largest stomata with the experimental mean value of 587.3µ2.

 

Phylogeny

A consensus phylogenetic tree based on 42 morphological and micro-morphological characters obtained after 1,000 replications revealed that the dendrogram is divided into three clusters (Figure 1).  Cluster I comprises seven taxa: C. maccannii, C. panchganiensis, C. rollae, C. attenuata var. attenuata, C. sahyadrica, C. maharashtrensis, and C. anantii.  All these taxa are clustered with unit distance of 0.2–0.8.

Cluster II comprises total 15 taxa with unit distance of 0.2–0.7.  All the taxa of this cluster have paracytic stomata.  This cluster further has two sub-clusters.  The sub-cluster IIa comprises eight taxa: C. attenuata var. mookambikae, C. mahabalei var. mahabalei, C. media, C. candelabrum, C. evansii, C. fantastica, C. oculata, and C. lawii.  Taxa in this sub-cluster have two distinct subsidiaries in all the taxa.  From the dendrogram it is observed that the taxa, C. evansii, C. fantastica, C. oculata, and C. lawii are closely related having unit distance of 0.2–0.4.  Another sub-cluster IIb comprises seven taxa having indistinct and variable subsidiaries: C. hirsuta, C. vincifolia, C. odorata, C. anjanerica, C. jainii, C. mahabalei var. hemalatae, and C. concanensis.

The Cluster III is an externally linked group having four taxa with unit distance of 0.2–0.8.  It comprised two varieties of C. bulbosa, C. elegans, and C. juncea.

 

DISCUSSION

 

As the genus Ceropegia is considered to be xerophytic because of its escape mechanism against the hot period by perennial tubers.  It should be preferably hypostomatic and the results are in corroboration with the concept, but the exceptions are both the varieties of C. bulbosa as they have amphistomatic leaves.  Both the varieties of this taxon are usually distributed in dry rain-shadowed area of the Western Ghats, even though they are amphistomatic; this may be due to more succulent leaves than other taxa.  Metcalfe & Chalk (1950) reported isobilateral leaves in the species of Ceropegia and Hoya R.Br. having fleshy leaves.  Therefore, present results also confirm the amphistomatic nature of some taxa in Ceropegia which have fleshy leaves.  The presence of stomata only on lower surface of leaf is an adaptation to reduce the rate of transpiration.  It is interesting to note that except C. candelabrum, C. elegans, and C. juncea, all the taxa have tubers and their vegetative growth is confined to the rainy season only, but still they have hypostomatic leaves.  This is an interesting fact and raises further curiosities towards the taxa.  The taxa C. candelabrum, C. elegans, and C. juncea generally remain in their active growth during summer season also and therefore their hypostomatic nature is justified, but for other taxa which grow in high rainfall area and escape the dry spell, especially about 8–9 months of year except rainy season and still have the hypostomatic leaves.  This fact is interesting and the hypostomatic leaves must be a qualitative character governed by genes only; because in the present study beside C. bulbosa three more taxa, viz., C. candelabrum, C. elegans and C. juncea, have succulent leaves but have only hypostomatic nature unlike C. bulbosa. 

The type of stomata is paracytic in most of the taxa (16 out of 26) under study.  Rubiaceous type (paracytic) stomata are reported to be common feature of many genera of Asclepiadaceae (present Asclepiadoideae of Apocynaceae) (Metcalfe & Chalk 1950; Paliwal et al. 1980).  The results of present study showed similar observations about the type of stomata in Ceropegia, but besides paracytic stomata, tetracytic, anomocytic and mixed stomata of isotricytic + tetracytic, & paracytic + anomocytic are also found.  Thus, the variations of type of stomata occur in the genus.  

The results revealed that, mean value of stomatal index for the taxa under study, i.e., experimental mean is 14.75±0.35.  The highest SI is found in C. attenuata var. attenuata while the lowest value for SI is observed in C. juncea (8.18±0.37).  The mean value for stomatal density/mm2 of leaf area is 252.31±8.50 with the highest value of 403.64±10.60 in C. maharashtrensis and the lowest 98.18±3.40 in C. juncea.  There is no correlation observed among the taxa with respect to SI values, but for SD the taxa occurring in the dry climates and with succulent habits have relatively lower values for the parameter.  The SI remain unchanged even in different seasons in soybean cultivars (Rahangdale 2003) suggesting true genetic nature of this parameter.  The SD is the lowest in C. juncea a succulent taxon with highly reduced leaves and increasing to some extent in C. bulbosa var. lushii, C. bulbosa var. bulbosa, and C. hirsuta.  Low SD helps these taxa to retain more water in plant body and survive during dry spell of the year.  On the other hand, taxa growing under high rainfall conditions, viz., C. attenuata, C. anantii, C. jainii, C. media, C. mahabalei, C. anjanerica, and C. maharashtrensis, have high stomatal density ranging from 325 to 403 stomata/mm2, thereby adapting to the high annual rainfall of about 2,000–4,000 mm.  It is interesting to note that, C. concanensis found in the Konkan region, on lateritic rock plateaux with very negligible soil have intermediate value of stomatal density.  This is in accordance with it’s relatively broader leaves and habitat because the rain water never remain on the sloppy plateaux.  Such plateaux show relatively dry conditions as compared to the little more soil rich habitats where C. anantii and C. attenuata occur.

Present study revealed that on the basis of micro-morphological characters, the taxa with overlapping vegetative characters can be easily identified.  The type of stomata, number and nature of subsidiary cells and anticlinal wall pattern are important characters to differentiate between very closely allied taxa at species as well as infraspecific ranks.  This has been shown in an artificial key as well as the morphological phylogeny tree derived in the present study.  These results are in corroboration of the previous studies in different angiosperm taxa.  Metcalfe & Chalk (1988) reported that stomatal index is independent of the changes in epidermal cell size brought by the environmental factors, and therefore, the SI is generally considered as a taxonomic character along with the others.  Many of the works have considered SI as a strong taxonomic character to delimit the allied taxa of family Vitaceae (Patil & Patil 1983, 1984), in Bauhinia L. (Kotresha & Seetharam 1995), and Cassia L. species (Kotresha & Seetharam 2000).  The leaf micromorphological characters are very significant to compare the fossil taxa with the allied species of extant taxa (Dilcher 1974).  Doyle & Endress (2000) observed that, the morphological evidences overcome the weak molecular evidences while assigning the phylogeny of angiosperms.  Kotresha & Seetharam (2000) studied epidermal micromorphology of Cassia L. species and delimited the species within the genus on the basis of stomatal index, size, and epidermal cell wall structure (especially the anticlinal wall pattern) and the type of stomata.  Thus, stomatal characters and micro-morphology can play a very significant role in resolving the taxonomic ambiguities.  Present study is also showing similar outcomes giving significant information in delimitation of Ceropegia species and varieties on the basis of micromorphological characters.  For example, two varieties of C. mahabalei, viz., var. mahabalei and var. hemalatae, are different with respect to many characters including stem scandant, undulate leaf margins, 2–4 indistinct subsidiaries and rounded anticlinal walls of epidermal cells in latter, whereas var. mahabalei have erect stout stem, straight leaf margins, two distinct subsidiaries, and undulate epidermal anticlinal walls.  These characters are other than the characters which are provided in original protologue.  Variety hemalatae does not match in any characters with C. oculata.  Similar is the case of varieties of C. attenuata, viz., var. attenuata and var. mookambikae.  The later variety has paracytic stomata with two distinct subsidiaries and SI 15.05, while the variety attenuata has mixed stomata of isotricytic and tetracytic types with 3–4 indistinct subsidiaries stomatal index 21.80.  As per the key provided in the present study variety mookambikae is more allied to C. concanensis than with C. attenuata var. attenuata.

The consensus phylogenetic tree has three clusters.  The type of stomata is defining character for these three clusters and supported by the number & nature of subsidiary cells.  Cluster I is having anomocytic and mixed type of stomata with indistinct variable number of (two/three/four/five) subsidiary cells.  All the taxa in this cluster are erect ones.  Cluster II comprises total 15 taxa having paracytic stomata.  This cluster further has two sub-clusters.  Sub-cluster IIa comprises eight taxa having two distinct subsidiaries in all.  From the dendrogram it is observed that the taxa, C. evansii, C. fantastica, C. oculata, and C. lawii are closely related having unit distance of 0.2–0.4.  Along these C. candelabrum is separated from others on the basis of having fascicled roots and undulate anticlinal epidermal walls.  Sub-cluster IIb comprises seven taxa having indistinct and variable subsidiaries.  C. mahabalei var. hemalatae is separated from others on the basis of scandant habit, undulate leaf margins and high SI value.  The cluster III is an externally linked group has four taxa clustered with unit distance of 0.2–0.8.  It comprised two varieties of C. bulbosa, C. elegans, and C. juncea.  This is the group of taxa having succulent stems and leaves.  Among them C. juncea is placed as distinct taxon as it has highly reduced leaves.  Among these C. elegans has tetracytic stomata while others have paracytic ones and therefore, it is placed little distantly.  The dendrogram depicts clear differences among related taxa on the basis of micromorphology, especially the type of stomata, anticlinal wall pattern, SI and supported by gross morphology.  In the present study, the grouping of C. maccannii, C. panchganiensis, C. sahyadrica, and C. rollae in first cluster, as well as C. anjanerica, C. mahabalei, C. jainii, C. media, and C. odorata in second cluster is in corroboration with the molecular phylogeny done by Surveswaran et al. (2009) where these taxa were placed in two separate clusters. 

It is necessary to discuss here the delimitation of some of the taxa in present study.  C. mahabalei var. mahabalei and C. mahabalei var. hemalatae are distinct in gross morphology of stem, leaves, inflorescence and the corolla beak, in a similar way they also differ in having indistinct 2–4 subsidiaries, rounded anticlinal walls and higher SI in the later variety.  In the dendrogram they are also placed apart from each other on the basis of above characters.  Similarly, two varieties of C. attenuata, viz., var. attenuata and var. mookambikae, are also placed distantly in the dendrogram in two different clusters.  This is because of the type of stomata, number & characters of subsidiaries, size of stomata and SI.  The most confusing taxa in terms of vegetative and floral morphology are C. rollae and C. lawii, as they are morphologically very similar to each other.  Results of the present study separated them in the dendrogram as well as in the identification key on the basis of type of stomata, number and feature of subsidiaries, anticlinal wall pattern, and size of stomata.  Thus, their identity can be confirmed on the basis of micro-morphology even in vegetative state.  Similarly, all the above mentioned taxa are separated on the basis of micro-morphological characters in the artificial key also.  Thus, micro-morphological characters when combined with the gross morphological characters give better opportunity for correct identification of the taxa.  The inter-specific variations in the stomatal characters such as stomatal index and stomatal frequency in Vitis L., Cissus L., and Leea D. Royen ex L. were studied by Patil & Patil (1984) and the taxa within these three genera were delimited on the basis of the stomatal characters and relationship among them was also established.  Stomatal size and frequency was used to delimit between 56 species of genera of family Vitaceae by Patil & Patil (1983) and opined that, the stomatal data is supporting other characters to delimit the species and also to establish phylogenetic relationship to some extent.  The results of present study show a similar trend in the genus Ceropegia. 

Therefore, on the basis of studied micromorphological characters combined with other vegetative characters 26 taxa of Ceropegia at species and infraspecific level are delimited and an identification key is being provided for easy identification.  These characters provide a very easy way of identification even in absence of flowers of these taxa.  

 

 

CONCLUSION

 

The micro-morphology of taxa in the genus Ceropegia L. is revealed and is determinative for the identification of taxa even in a vegetative state in combination with the other general morphological characters.  The type of stomata, number and nature of subsidiary cells, anticlinal epidermal wall pattern and stomatal index are key characters for differentiation of the taxa.  Besides paracytic stomata, anomocytic, tetracytic and mixed, isotricytic + tetracytic and paracytic + anomocytic stomata are found in the genus Ceropegia.  These characters are crucial in correct identification of the taxa at species and infraspecific level.  Occurrence of tetracytic and mixed stomata is a first report in the genus by this study.  It is also confirmed that, C. mahabalei var. hemalatae and C. attenuata var. mookambikae are distinct taxa from their allied taxa, respectively.

 

 

Key for identification of species on the basis of vegetative and micro-morphological characters

 

1. Plants erect ………………………… ……………………………………………………………………………………………………………………………....……………. 2

1. Plants twiner ...…………………………………… ………………………………………………………………………………………………………………………………..... 3

2. Leaves broadly ovate ..………………………………………………… ……………………………………………………………………………………………………… 4

2. Leaves lanceolate/linear ...………………………………………………… ………………………………………………………………………………………………… 5

4. Stomata paracytic or anomocytic ……………………………………………………………………… …………………………………………………………………… 6

4. Stomata mixed ...……………………………………………………………………………… …………………………………………………………………………………….. 7

6. Stomata paracytic, subsidiaries 2 distinct, epidermal cell wall undulate …………………………………………………………………. C. lawii

6. Stomata anomocytic, subsidiaries 4–5 indistinct, epidermal cell wall straight / rounded ……………… ………………………………….. 8

7. Stomata para & anomocytic, subsidiaries 2–4, epidermal cell wall straight ……………………………… …………………………….... C. rollae

7. Stomata isotricytic & tetracytic, subsidiaries 3–4 indistinct ……………………………..………  ……………………………… ………………….… 9

8. Epidermal cell wall straight, SI 17.36 ………………………………………………….………… … ………………………………………………... C. maccannii

8. Epidermal cell wall rounded, SI 11.24 ……………………………………………………… ………………………………………………… C. panchganiensis

9. Epidermal cell wall rounded, SI 19.94, SD 285.45 …………………………… ………………………………………………………………… C. sahyadrica

9. Epidermal cell wall straight, SI 15.48, SD 403.64 ……………………………… …………………………………………………………… C. maharashtrensis

5. Plants robust up to 1m tall, stomata paracytic ...………………………………………………………… …………………… ……………………………… 10

5. Plants small / delicate, shorter than 0.5m tall, stomata paracytic / other types ..........………………………………........……………… …. 11

10. Stem stout, leaf margin straight, subsidiary 2, distinct, epidermal cell wall undulate ..................... C. mahabalei var. mahabalei

10. Stem scandant, leaf margin undulate, subsidiary 2–4, indistinct, epidermal cell wall rounded …… C. mahabalei var. hemalatae

11. Stomata paracytic, subsidiaries distinct .……………………….…………………………… …………………………………………………………… 12

11. Stomata isotricytic & tetractytic, subsidiaries 3–4 indistinct ……………………….……… ……………………………………………………… ... 13

12. Subsidiaries 2 or 4, epidermal cell wall undulate ....……………………………………………………………………………………… ………………. 14

12. Subsidiaries 2–3, epidermal cell wall rounded / undulate .……………………………………………………………………………………… ……………… 15

14. Subsidiaries 2, SI 15.05, SD 329.09 ………………………………………  ……………………………………………… C. attenuata var. mookambikae

14. Subsidiaries 4, SI 12.11, SD 258.18 …………………………………………………  …… ………………………………………………………… C. concanensis

15. Leaves hirsute, epidermal cell wall undulate, SI 14.69, SD 338.18 ………………… … …………………………………………………. C. anjanerica

15. Leaves sparsely hairy, epidermal cell wall rounded, SI 12.26, SD 370.91 ……………… ……………………………………………………… C. jainii 

13. Epidermal cell wall undulate, SI 21.80, SD 300.0 ……………………………………… … …………………………….. C. attenuata var. attenuata

13. Epidermal cell wall rounded, SI 16.71, SD 390.91 ……………………………………… …………………………………………………………… C. anantii

3. Plants succulent, leaves ovate/lanceolate/linear/minute, epidermal cell wall straight ........……………………………………… ......……… 16

3. Plants non succulent, leaves ovate/ lanceolate, epidermal cell wall otherwise ………………….........……………… ……………………....... 17

16. Leaves minute, hypo-stomatic, stomata paracytic, subsidiaries 2–4 distinct ……………… ………………………………………………. C. juncea

16. Leaves conspicuous, amphi-stomatic, stomata anomocytic, subsidiaries 3–4 indistinct …....…………………… ....…..................... 18

18. Leaves ovate-lanceolate, SI 15.60, SD 127.27 …………………………………………… ………………………………………… C. bulbosa var. bulbosa

18. Leaves linear, SI 13.10, SD 105.45 ……………………………………………… …………………………………………………………. C. bulbosa var. lushii

17. Leaves lanceolate, stomata paracytic ………………………………………………………...………………………………… …………………………………. 19

17. Leaves broadly ovate, stomata otherwise ……………………………………………………………………………………………… ………..…………… 20

19. Leaves minutely hairy, veins winged below, epidermal cell wall straight, SI 14.85, SD 314.55 ……………… ………………….. C. media

19. Leaves glabrous, veins not winged, epidermal cell wall rounded, SI 13.51, SD 250.91 ………… …………………………………… C. odorata

20. Plants almost glabrous, stomata para or tetracytic ………………………………………………………………………………… ………………………. 21

20. Plants hairy, stomata paracytic …………………………………………………………………………………………………………………………… …………….. 22

21. Stomata paracytic, subsidiaries 2 distinct, epidermal cell wall undulate ………………… …………………………………… C. candelabrum

21. Stomata tetracytic, subsidiaries 4 indistinct, epidermal cell wall rounded ………………………..…………………………… C. elegans

22. Epidermal cell wall rounded / straight, subsidiaries distinct ………………………………………………………………… ……………... 23

22. Epidermal cell wall undulate, subsidiaries distinct / indistinct …….………………………………………...……………………………… ……. 24

23. Subsidiaries 2, epidermal cell wall straight ………………………………… ………………………………………………………………. C. fantastica

23. Subsidiaries 2–4, epidermal cell wall rounded …………………………………………………………………………………………… …………………… 25

25. Plants densely hirsute, SI 11.88, SD 152.73 ……………………………………………………… ……………………………………………………… C. hirsuta

25. Plants sparsely hirsute, especially on leaves, SI 14.76, SD 230.91 ……………… …………………………………………………………… C. oculata

24. Subsidiaries 2 distinct …………………………………………………………………… ………………………………………………………........………. C. evansii

24. Subsidiaries 2–3 indistinct …………………………………………………………....... ..............................................................………… C. vincifolia

 

 

 

Table 1. Plant materials (taxa) used in the present study.

 

 

Taxa name

Status*

Distribution*

Locality of collection

Specimen number

1

Ceropegia anantii Yadav et al.

EN

Endemic; MS

Konkan, Ratnagiri, MS

1122

2

C. anjanerica Malpure et al.

CR

Endemic; MS

Anjaneri, Nashik, MS

23926

3

C. attenuata Hook. var. attenuata

EN

Endemic; MS, Goa, KA, Raj.

Junnar, Pune, MS

907, 1116, 21441 (AHMA)

4

C. attenuata Hook. var. mookambikae Diwakar & Singh

EN

Endemic; MS, KA

Konkan, Ratnagiri, MS

1112

5

C. bulbosa Roxb. var. bulbosa

Common

Asia & Africa

Junnar, Pune, MS

18544, 18545 (AHMA)

6

C. bulbosa Roxb. var. lushii (Grah.) Hook. f.

Common

India, Pakistan

Junnar, Pune, MS

21685, 24312 (AHMA)

7

C. candelabrum L.

VU

India, Sri Lanka

Waynad, KL

23924

8

C. concanensis Kamble et al.

EN

Endemic; MS

Konkan, Ratnagiri, MS

1120, 1121

9

C. elegans Wall.

Occasional

India, Sri Lanka

Coimbatore, TN

23923

10

C. evansii McCann

EN

Endemic; MS

Ambegaon, Pune, MS

139, 1117, 1118

11

C. fantastica Sedgwick

CR

Endemic; MS, KA, Goa

Amboli, Sindhudurg, MS

23920

12

C. hirsuta Wight & Arn.

Common

India, Thailand

Junnar, Pune, MS

0466, 23908, 23909, 23910,  23911,

13

C. jainii Ansari & Kulkarni

EN

Endemic; MS

Kas, Satara, MS

23927

14

C. juncea Roxb.

Occasional

India, Sri Lanka

Coimbatore, TN

23925

15

C. lawii Hook. f.

EN

Endemic; MS

Junnar, Pune, MS

0316

16

C. maccannii Ansari

EN

Endemic; MS

Simhagarh, Pune, MS

0832

17

C. mahabalei Hemadri & Ansari var. hemalatae Rahangdale & Rahangdale

CR

Endemic; MS

Junnar, Pune, MS

0136, 0137 (Types), 1114

18

C. mahabalei Hemadri & Ansari var. mahabalei

CR

Endemic; MS

Junnar, Pune, MS

0138, 0908, 23915, 23916, 23918

19

C. maharashtrensis Punekar et al.

CR

Endemic; MS

Junnar, Pune, MS

23222

20

C. media (Huber) Ansari

EN

Endemic; MS

Junnar, Pune, MS

0774, 1119, 22735X, 23917

21

C. oculata Hook.

VU

Endemic; MS, KL, TN

Junnar, Pune, MS

23902, 23903, 23904, 23914

22

C. odorata Nimmo ex. Hook f.

CR

Endemic; MS, Raj, Guj.

Junnar, Pune, MS

22922

23

C. panchganiensis Blatt. & McCann

CR

Endemic; MS

Junnar, Pune, MS

18549 (AHMA)

24

C. rollae Hemadri

CR

Endemic; MS

Junnar, Pune, MS

1123, 23209, 23334, 23912, 23913

25

C. sahyadrica Ansari & Kulkarni

CR

Endemic; MS

Ambegaon, Pune, MS

0188, 23907

26

C. vincifolia Hook.

VU

Endemic; MS

Junnar, Pune, MS

0313

CR—Critically Endangered | EN—Endangered | VU—Vulnerable | Guj—Gujarat | KA—Karnataka | KL—Kerala | MS—Maharashtra | Raj—Rajastha | TN—Tamil Nadu | *—as per Singh et al. (2015).  Specimens are deposited at AHMA—Agharkar Research Institute, Pune and Herbarium of Hon. Balasaheb Jadhav College, Ale.

 

 

Table 2. Epidermal and stomatal characters observed in the taxa under study.

 

Name of taxon

Stomatal distribution

Type of Stomata #

Subsidiary cells

Anticlinal cell wall pattern (Epidermal Cell outline) $

Number

Character

1

Ceropegia anantii

Hypostomatic

Isotricytic & Tetracytic

3–4

Indistinct

Rounded

2

C. anjanerica

Hypostomatic

Paracytic

2–3

Distinct

Undulate

3

C. attenuata var. attenuata

Hypostomatic

Isotricytic & Tetracytic

3–4

Indistinct

Undulate

4

C. attenuata var. mookambikae

Hypostomatic

Paracytic

2

Distinct

Undulate

5

C. bulbosa var. bulbosa

Amphistomatic

Anomocytic

3–4

Indistinct

Straight

6

C. bulbosa var. lushii

Amphistomatic

Anomocytic

3–4

Indistinct

Straight

7

C. candelabrum

Hypostomatic

Paracytic

2

Distinct

Undulate

8

C. concanensis

Hypostomatic

Paracytic

4

Indistinct

Undulate

9

C. elegans

Hypostomatic

Tetracytic

4

Indistinct

Rounded

10

C. evansii

Hypostomatic

Paracytic

2

Distinct

Undulate

11

C. fantastica

Hypostomatic

Paracytic

2

Distinct

Straight

12

C. hirsuta

Hypostomatic

Paracytic

3–4

Distinct

Rounded

13

C. jainii

Hypostomatic

Paracytic

2–3

Distinct

Rounded

14

C. juncea

Hypostomatic

Paracytic

2–4

Distinct

Straight

15

C. lawii

Hypostomatic

Paracytic

2

Distinct

Undulate

16

C. maccannii

Hypostomatic

Anomocytic

4–5

Indistinct

Straight

17

C. mahabalei var. hemalatae

Hypostomatic

Paracytic

2–4

Indistinct

Rounded

18

C. mahabalei var. mahabalei

Hypostomatic

Paracytic

2

Distinct

Undulate

19

C. maharashtrensis

Hypostomatic

Isotricytic & Tetracytic

3–4

Indistinct

Straight

20

C. media

Hypostomatic

Paracytic

2

Distinct

Straight

21

C. oculata

Hypostomatic

Paracytic

2

Distinct

Undulate

22

C. odorata

Hypostomatic

Paracytic

2

Indistinct

Rounded

23

C. panchganiensis

Hypostomatic

Anomocytic

4–5

Indistinct

Rounded

24

C. rollae

Hypostomatic

Paracytic & Anomocytic

2–4

Distinct & Indistinct

Straight

25

C. sahyadrica

Hypostomatic

Isotricytic & Tetracytic

3–4

Indistinct

Rounded

26

C. vincifolia

Hypostomatic

Paracytic

2–3

Indistinct

Undulate

#—as per Prabhakar (2004) | $—as per Dilcher (1974) | Curved—Rounded | Wavy—Undulate.

 

 

Table 3. The stomatal measurements recorded in the taxa.

 

Name of taxon

Stomatal index

Stomatal density/mm2

Stomatal length (µ)

Stomatal width (µ)

Stomatal pore length (µ)

Size of stomata (µ2)

Mean

SE ±

Mean

SE ±

Mean

SE ±

Mean

SE ±

Mean

SE ±

1

C. anantii

16.71

0.28

390.91

10.50

26.00

0.61

18.50

0.61

17.50

1.12

481.0

2

C. anjanerica

14.69

0.16

338.18

9.85

31.00

0.61

21.00

1.00

22.00

0.94

651.0

3

C. attenuata var. attenuata

21.80

0.47

300.00

12.03

28.50

1.00

20.50

0.50

16.50

0.61

584.3

4

C. attenuata var. mookambikae

15.05

0.16

329.09

7.99

23.00

0.50

15.00

0.79

12.00

0.50

345.0

5

C. bulbosa var. bulbosa ˄

14.04

1.64

101.82

2.40

33.5

1.7

21.5

1.00

23.5

0.61

 

 

C. bulbosa var. bulbosa ˅

17.15

1.05

152.73

2.68

31.0

1.0

18.5

1.27

19.0

1.27

 

 

C. bulbosa var. bulbosa *

15.60

0.60

127.27

7.41

32.25

1.35

20.00

1.13

21.25

0.94

645.0

6

C. bulbosa var. lushii ˄

13.80

1.04

96.36

1.70

31.5

0.61

20.0

0.0

20.5

0.5

 

 

C. bulbosa var. lushii ˅

12.41

1.13

114.55

2.19

29.5

0.50

19.5

0.5

19.5

0.5

 

 

C. bulbosa var. lushii *

13.10

0.48

105.45

4.17

30.50

0.55

19.75

0.25

20.00

0.50

602.4

7

C. candelabrum

14.39

0.28

145.45

3.71

31.50

0.61

20.50

0.50

20.00

0.00

645.8

8

C. concanensis

12.11

0.30

258.18

9.36

26.00

0.61

15.50

0.50

13.00

0.50

403.0

9

C. elegans

12.39

0.23

198.18

5.80

30.00

0.79

21.00

0.61

20.50

0.50

630.0

10

C. evansii

15.04

0.52

209.09

12.03

33.00

0.50

19.50

0.50

19.50

0.50

643.5

11

C. fantastica

16.94

0.46

269.09

7.84

28.50

1.27

23.00

1.22

16.00

0.61

655.5

12

C. hirsuta

11.88

0.40

152.73

5.17

30.00

0.00

22.00

1.46

19.50

0.50

660.0

13

C. jainii

12.26

0.30

370.91

8.58

31.50

1.00

20.00

0.00

20.50

0.50

630.0

14

C. juncea

8.18

0.37

98.18

3.40

39.00

1.50

26.50

1.70

27.00

0.94

1033.5

15

C. lawii

14.49

0.46

263.64

11.13

29.00

1.00

15.50

0.94

18.50

0.61

449.5

16

C. maccannii

17.36

0.41

254.55

8.30

28.00

0.50

23.00

0.50

18.50

0.61

644.0

17

C. mahabalei var. hemalatae

20.32

0.33

341.82

10.54

30.50

0.50

20.00

0.00

24.00

1.00

610.0

18

C. mahabalei var. mahabalei

16.50

0.12

325.45

10.05

29.50

0.50

19.50

0.50

24.50

0.94

575.3

19

C. maharashtrensis

15.48

0.18

403.64

10.60

28.00

1.46

21.00

0.61

15.50

0.50

588.0

20

C. media

14.85

0.46

314.55

17.39

28.00

1.66

16.25

1.12

16.25

1.12

455.0

21

C. oculata

14.76

0.52

230.91

8.27

32.00

0.94

16.75

0.50

20.00

1.37

536.0

22

C. odorata

13.51

0.43

250.91

8.35

28.00

0.94

21.50

0.61

21.00

0.61

602.0

23

C. panchganiensis

11.24

0.28

205.45

5.33

29.50

0.50

21.00

0.61

19.50

0.50

619.5

24

C. rollae

12.99

0.22

201.82

4.61

30.00

0.00

18.50

0.61

19.00

0.61

555.0

25

C. sahyadrica

19.94

0.60

285.45

15.19

30.00

0.00

16.00

0.61

20.00

0.00

480.0

26

C. vincifolia

11.81

0.20

189.09

3.40

32.50

0.00

20.00

0.00

22.50

0.00

650.0

 

Experimental mean @ 25df

14.75

0.35

252.31

8.50

29.84

0.73

19.68

0.67

19.40

0.64

587.3

*—the data of amphistomatic taxa are taken from mean of both the surfaces and then the experimental mean is calculated | ˄—upper surface of leaf | ˅—lower surface of leaf.

 

Table 4. List of characters and character state used for phylogenetic analysis.

 

Character with character state

1

Tuber:  Absent (0), Present (1)

2

Stem erect: Absent (0), Present (1)

3

Stem twining: Absent (0), Present (1)

4

Stem scandant: Absent (0), Present (1)

5

Stem: Non succulent (0), Succulent(1)

6

Leaves: Large (0), Minute (1)

7

Plant habit:  Small (0), Robust (1)

8

Leaves ovate: Absent (0), Present (1)

9

Leaves lanceolate: Absent (0), Present (1)

10

Leaves linear: Absent (0), Present (1)

11

Leaves: Non succulent (0), Succulent (1)

12

Leaves: Non hairy (0), Hairy (1)

13

Leaf margin: Straight (0),  Undulate (1)

14

Leaf veins winged on lower surface: Not winged (0), Winged (1)

15

Leaf: Amphi-stomatic (0), Hypo-stomatic (1)

16

Epidermal cell anticlinal wall, Straight: Absent (0), Present (1)

17

Epidermal cell anticlinal wall, Rounded: Absent (0), Present (1)

18

Epidermal cell anticlinal wall, Undulate: Absent (0), Present (1)

19

Stoma: Mixed types (0), Single type (1)

20

Stoma paracytic: Absent (0), Present (1)

21

Stoma anomocytic: Absent (0), Present (1)

22

Stoma tetracytic: Absent (0), Present (1)

23

Stoma isotricytic & tetracytic: Absent (0), Present (1)

24

Stoma paracytic & anomocytic: Absent (0), Present (1)

25

Subsidiary cells: Indistinct (0), Distinct (1)  

26

Subsidiary cell number two: Absent (0), Present (1)

27

Subsidiary cell number four: Absent (0), Present (1)

28

Subsidiary cell number 2–3:  Absent (0), Present (1)

29

Subsidiary cell number 3–4: Absent (0), Present (1)

30

Subsidiary cell number 4–5: Absent (0), Present (1)

31

Size of stoma 300–450 μ: Out of range (0), Within range (1)

32

Size of stoma 450–600 μ: Out of range (0), Within range (1)

33

Size of stoma 600–750 μ: Out of range (0), Within range (1)

34

Size of stoma 750–1100 μ: Out of range (0), Within range (1)

35

Stomatal index (SI) range value 8–11 : Out of range (0), Within range (1)

36

Stomatal index (SI) range value 11–14: Out of range (0), Within range (1)

37

Stomatal index (SI) range value 14–17: Out of range (0), Within range (1)

38

Stomatal index (SI) range value 17–22: Out of range (0), Within range (1)

39

Stomatal density (SD) range value <100:  Out of range (0), Within range (1)

40

Stomatal density (SD) range value 100-200: Out of range (0), Within range (1)

41

Stomatal density (SD) range value 200-300: Out of range (0), Within range (1)

42

Stomatal density (SD) range value 300-400: Out of range (0), Within range (1)

 

 

Table 5. Character state of taxa under study (Character no. as per Table 4).

Sno

Character No.

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

Taxa

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

C. anantii

1

1

0

0

0

0

0

0

0

1

0

1

0

0

1

0

1

0

0

0

0

0

1

0

0

0

0

0

1

0

0

1

0

0

0

0

1

0

0

0

0

1

2

C. anjanerica

1

1

0

0

0

0

0

0

1

0

0

1

0

0

1

0

0

1

1

1

0

0

0

0

1

0

0

1

0

0

0

0

1

0

0

0

1

0

0

0

0

1

3

C. attenuata var. attenuata

1

1

0

0

0

0

0

0

0

1

0

1

0

0

1

0

0

1

0

0

0

0

1

0

0

0

0

0

1

0

0

1

0

0

0

0

0

1

0

0

1

0

4

C. attenuata var. mookambikae

1

1

0

0

0

0

0

0

1

0

0

1

0

0

1

0

0

1

1

0

0

0

0

0

1

1

0

0

0

0

1

0

0

0

0

0

1

0

0

0

0

1

5

C. bulbosa var. bulbosa

1

0

1

0

1

0

1

1

0

0

1

0

0

0

0

1

0

0

1

0

1

0

0

0

0

0

0

0

1

0

0

0

1

0

0

0

1

0

0

1

0

0

6

C. bulbosa var. lushii

1

0

1

0

1

0

1

0

0

1

1

0

0

0

0

1

0

0

1

0

1

0

0

0

0

0

0

0

1

0

0

0

1

0

0

1

0

0

0

1

0

0

7

C. candelabrum

0

0

1

0

1

0

1

1

0

0

1

0

0

0

1

0

0

1

1

1

0

0

0

0

1

1

0

0

0

0

0

0

1

0

0

0

1

0

0

1

0

0

8

C. concanensis

1

1

0

0

0

0

0

0

0

1

0

1

0

0

1

0

0

1

1

1

0

0

0

0

0

0

1

0

0

0

1

0

0

0

0

1

0

0

0

0

1

0

9

C. elegans

0

0

1

0

1

0

1

1

0

0

1

0

0

0

1

0

1

0

1

0

0

1

0

0

0

0

1

0

0

0

0

0

1

0

0

1

0

0

0

1

0

0

10

C. evansii

1

0

1

0

0

0

1

1

0

0

0

1

0

0

1

0

0

1

1

1

0

0

0

0

1

1

0

0

0

0

0

0

1

0

0

0

1

0

0

0

1

0

11

C. fantastica

1

0

1

0

0

0

1

1

0

0

0

1

0

0

1

1

0

0

1

1

0

0

0

0

1

1

0

0

0

0

0

0

1

0

0

0

1

0

0

0

1

0

12

C. hirsuta

1

0

1

0

0

0

1

1

0

0

0

1

0

0

1

0

1

0

1

1

0

0

0

0

1

0

0

0

1

0

0

0

1

0

0

1

0

0

0

1

0

0

13

C. jainii

1

1

0

0

0

0

0

0

1

0

0

1

0

0

1

0

1

0

1

1

0

0

0

0

1

0

0

1

0

0

0

0

1

0

0

1

0

0

0

0

0

1

14

C. juncea

0

0

1

0

1

1

1

0

1

0

1

0

0

0

1

1

0

0

1

1

0

0

0

0

1

0

0

1

0

0

0

0

0

1

1

0

0

0

1

0

0

0

15

C. lawii

1

1

0

0

0

0

1

1

0

0

0

1

0

0

1

0

0

1

1

1

0

0

0

0

1

1

0

0

0

0

1

0

0

0

0

0

1

0

0

0

1

0

16

C. maccannii

1

1

0

0

0

0

1

1

0

0

0

1

0

0

1

1

0

0

1

0

1

0

0

0

0

0

0

0

0

1

0

0

1

0

0

0

0

1

0

0

1

0

17

C. mahabalei var. hemalatae

1

0

0

1

0

0

1

0

0

1

0

1

1

0

1

0

1

0

1

1

0

0

0

0

0

0

0

1

0

0

0

0

1

0

0

0

0

1

0

0

0

1

18

C. mahabalei var. mahabalei

1

1

0

0

0

0

1

0

0

1

0

1

0

0

1

0

0

1

1

1

0

0

0

0

1

1

0

0

0

0

0

1

0

0

0

0

1

0

0

0

0

1

19

C. maharashtrensis

1

1

0

0

0

0

1

1

0

0

0

1

0

0

1

1

0

0

0

0

0

0

1

0

0

0

0

0

1

0

0

1

0

0

0

0

1

0

0

0

0

1

20

C. media

1

0

1

0

0

0

1

0

1

0

0

1

0

1

1

1

0

0

1

1

0

0

0

0

1

1

0

0

0

0

1

0

0

0

0

0

1

0

0

0

0

1

21

C. oculata

1

0

1

0

0

0

1

1

0

0

0

0

0

0

1

0

0

1

1

1

0

0

0

0

1

1

0

0

0

0

0

1

0

0

0

0

1

0

0

0

1

0

22

C. odorata

1

0

1

0

0

0

1

0

1

0

0

1

0

0

1

0

1

0

1

1

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

1

0

0

0

0

1

0

23

C. panchganiensis

1

1

0

0

0

0

1

1

0

0

0

1

0

0

1

0

1

0

1

0

1

0

0

0

0

0

0

0

0

1

0

0

1

0

0

1

0

0

0

0

1

0

24

C. rollae

1

1

0

0

0

0

1

1

0

0

0

1

0

0

1

1

0

0

0

0

0

0

0

1

0

0

0

1

0

0

0

1

0

0

0

1

0

0

0

1

0

0

25

C. sahyadrica

1

1

0

0

0

0

1

1

0

0

0

1

0

0

1

0

1

0

0

0

0

0

1

0

0

0

0

0

1

0

0

1

0

0

0

0

0

1

0

0

1

0

26

C. vincifolia

1

0

1

0

0

0

1

1

0

0

0

1

0

0

1

0

0

1

1

1

0

0

0

0

0

0

0

1

0

0

0

0

1

0

0

1

0

0

0

1

0

0

 

 

For image - - click here

 

 

REFERENCES

 

Dilcher, D.L. (1974). Approaches to the identification of angiosperm leaf remains. Botanical Review 40(1): 1–159.

Diwakar, P.G. & R.Kr. Singh (2011). A new variety of Ceropegia attenuata Hook. (Asclepiadaceae) from Mookambika Wildlife Sanctuary, Karnataka, India. Indian Journal of Forestry 34: 209–212.

Doyle, J.A. & P.K. Endress (2000). Morphological phylogenetic analysis of basal angiosperms: comparison and combination with molecular data. International Journal of Plant Sciences 161(S6): S121–S153. https://doi.org/10.1086/317578

Hammer, Ø. & D.A.T. Harper (2006). Paleontological data analysis. Blackwell Publishing, Oxford, 351pp.

Hammer, Ø., D.A.T. Harper & P.D. Ryan (2001). PAST: Paleontological Statistics software package for education and data analysis. Palaentologia Electronica 4(1): 1–9.

Harper, D.A.T. (1999). Numerical Paleobiology. John Wiley & Sons, Inc, 478pp.

Jagtap, A.P. & N.P. Singh (1999). Ceropegia L, pp. 211–241. In: Fascicles of Flora of India, Fascicle 24. Botanical Survey of India, Kolkata, 332pp.

Kamble, S.S., A.N. Chandore & S.R. Yadav (2012). Ceropegia concanensis, a new species (Apocynaceae: Ceropegieae) from Western Ghats, India. Kew Bulletin 67: 1–6.

Kotresha, K. & Y.N. Seetharam (1995). Epidermal studies in some Bauhinia L. (Caesalpinoideae). Phytomorphology 45: 127–137.

Kotresha, K. & Y.N. Seetharam (2000). Epidermal micromorphology of some species of Cassia L. (Caesalpiniaceae). Phytomorphology 50(3&4): 229–237. 

Kumar, S.R., Sharma & M.D. Dwivedi (2018). Ceropegia mizoramensis and C. murlensis (Asclepiadaceae) – two new species from Northeast India with phylogenetic and morphological evidence support. Taiwania 63(2): 163–170.                                          

Metcalfe, C.R. & L. Chalk (1950). Anatomy of the Dicotyledons: leaves, stem, and wood in relation to taxonomy, Vol. 1 & 2. Oxford University Press, Amen House, London, pp. 476–487 & pp. 917–919. (Available at http://archive.org/details/in.ernet.dli.2015.231112. 21/January/2017)

Metcalfe, C.R. & L. Chalk (1988). Anatomy of Dicotyledons, 2nd edition, Vol. 1. Clarendon Press, Oxford, 276pp.

Paliwal, G.S., C.B. Malasi & U. Rajput (1980). Multiplicity of stomatal types in Calotropis procera R.Br. Proceedings of Indian National Science Congress B46(5): 667–672.

Patil, S.G. & V.P. Patil (1983). Stomatal studies in family Vitaceae. Biovigyanum 9: 97–104.

Patil, S.G. & V.P. Patil (1984). Inter-specific variations in stomatal characters in Vitis, Cissus and Leea. Biovigyanum 10: 13–20.

Plant List (2019). http://www.theplantlist.org (accessed 13 March 2019).

POWO (2020). http://www.plantsoftheworldonline.org/ (accessed 10 April 2020).

Prabhakar, M. (2004). Structure, delimitation, nomenclature and classification of stomata. Acta Botanica Sinica 46(2): 242–252.

Rahangdale, S.R. (2003). Genetic studies and stability analysis in soybean (Glycine max (L.) Merrill). PhD Thesis. Agharkar Research Institute, Pune; University of Pune, 273pp.

Rahangdale, S.S. & S.R. Rahangdale (2012). Variety Novae of Ceropegia mahabalei Hemadri et Ansari [Apocynaceae: Asclepiadoideae]. The Indian Forester 138(2): 201–203.

Singh, P., K. Karthigeyan, P. Lakshminarasimhan & S.S. Dash (2015). Endemic Vascular Plants of India. Botanical Survey of India, Kolkata, i-xvi+339pp.

Singh, R.K. & B.D. Chaudhary (1985). Biometrical Methods in Quantitative Genetic Analysis. Kalyani Publishers, New Delhi, 318pp.

Sujanapal, P., P.M. Salim, N.A. Kumar & N. Sasidharan (2013). A new species of Ceropegia (Apocynaceae: Asclepiadoideae) from India with notes on rare and threatened Ceropegia in Nilgiris of Western Ghats. Journal of Botanical Research Institute Texas 7(1): 341–345.

Surveswaran, S., M.Y. Kamble, S.R. Yadav & M. Sun (2009). Molecular phylogeny of Ceropegia (Asclepiadoideae, Apocynaceae) from Indian Western Ghats. Plant Systematics and Evolution 281: 51–63. https://doi.org/10.1007/s00606-009-0182-8