Redefinition of the Odorrana versabilis Group,with a New Species from China(Anura,Ranidae,Odorrana)

Taxonomic studies of the Odorrana versabilis group have been consistently disorganized,and they have often been incorrectly associated with an abandoned subgenus or genus Bamburana in existing literature.In this study,we conducted an integrative taxonomic analysis using molecular phylogenetic analysis of two mitochondrial gene fragments(16S rRNA and CO1)and morphological examination of 41 specimens collected during herpetological surveys in southern China.Our results confirmed the monophyly of O.versabilis group which exhibited distinct morphological traits.We also identified a cryptic lineage sister with O.exiliversabilis.Additionally,our study revealed that O.trankieni was nested within O.nasuta.Consequently,we redefined the morphological characteristics of the O.versabilis group,described a new species in this group,O.confusa sp.nov.,and proposed that O.trankieni be considered a junior synonym of O.nasuta.One of the most significant findings of this study was the observation of distinct morphological changes in adult males across all species within the O.versabilis group between the non-breeding and breeding seasons.This study contributes to research on various aspects of Asian amphibian fauna,including taxonomy,ecology,evolution,and physiology.

Research on the Karyotype and Evolution of Drosophila melanogaster Species Group

Mitotic metaphase chromosomes of 34 species of Drosophila melanogaster species group were examined. Certain new karyotypes were described for the first time, and their evolutionary and interspecific genetic relationships among 8 subgroups of D. melanogaster species group were analyzed systematically. The results were as follows. The basic karyotype of elegans subgroup was type A. The karyotypes of eugracilis subgroup, melanogaster subgroup, and ficusphila subgroup were all type C. The karyotypes of takahashii subgroup and suzukii subgroup were both type C and type D. The montium subgroup had six kinds of karyotypes types B, C, C＇, D, D＇, and E. The ananassae subgroup had three kinds of karyotypes： types F, G, and H. Thus, the melanogaster species group was classified into five pedigrees based on the diversity of these karyotypes： 1） elegans; 2） eugracilis-melanogasterficusphila; 3） takkahashii-suzukii; 4） montium; 5） ananassae. The above-mentioned results in karyotypic evolution were consistent with those of DNA sequence analysis reported by Yang except for the elegans subgroup and this subgroup was considered as the ancestral subgroup. Karyotype analysis of the same drosophila from different isofemale lines indicated that the same Drosophila from different places showed karyotypic variation which might be due to different geographical environment and evolutionary degree or interaction between the two factors.

Phylogeny of melanogaster Species Group Inferred from ND4L and ND4 Genes

The relationships within Drosophila melanogaster species group are controversial from morphology, chromosomes and DNA sequences. This study utilises a molecular approach aimed at uncovering the phylogenetic relationships among 33 taxa representing 8 subgroups of D. melanogaster species groups. Mitocondrial ND4L-ND4 was sequenced in the all 8 subgroups covering a wide geographic area. MP and Bayesian analysis produced an identical tree topology with relatively strong support in most nodes. It reveals that the melanogaster species group clustered in three main lineages：1）montium subgroup; 2） ananassae subgroup; 3） Oriental subgroups （ melanogaster, ficsphila, eugracilis, elegans, syzukii and takahashii）. The montium subgroup branched off first, followed by the ananassae subgroup. In the third lineage, melanogaster is the most divergent subgroup followed by ficsphila, eugracilis, elegans in that order. The suzukii and takahashii sister subgroups are the last to branch off.

Karyotype Differentiation in Newly Discovered Members of the Drosophila obscura Species Group from Yunnan,China

We examined mitotic chromosomes of three newly found members of the Drosophila obscura species group,D.luguensis,D.dianensis and D.limingi from Yunnan and compared their karyotypes to those of respective related species.D.luguensis possessed a diploid number of 12 chromosomes,comprising 3 pairs of metacentrics (V-shaped),2 pairs of acrocentrics (rod-like) and 1 pair of micro-chromosomes (dot-like).Both the X and Y were metacentrics.D.dianensis and D.limingi possessed a diploid number of 10 chromosomes,comprising 1 pair of large V-shaped,1 pair of moderate-sized V-shaped,2 pairs of submetacentric (J-shaped) chromosomes,and 1 pairs of dot-like chromosomes,with their X chromosomes were J-shaped and Y chromosomes were short rod-like ones.Based upon the results of chromosomal comparisons,geographic information of the sinobscura subgroup,as well inter-specific phylogenetic relationship deduced elsewhere,D.luguensis was considered to retain an ancestral form of the karyotype within this subgroup.The present observations have also implied that D.sinobscura (2n=12:2V,1J,2R,1D) might have derived from a sub-lineage of a pre-“sinobscura-hubeiensis” lineage by pericentric inversion of moderate-sized metacentric autosomes and D.hubeiensis (2n=10:4V,1D) from another sub-lineage of the same lineage by centric fusion of 2 pairs of acrocentric autosomes.Similar chromosomal changes of centric fusion,centric fission and/or pericentric inversion might have occurred during the course of species divergences between D.dianensis and D.subsilvestris (2n=12:3V,2R,1D),an European member closely related to D.dianensis,and between D.limingi and D.tsukubaensis (2n=12:3V,2R,1D),an East Asian member near to D.limingi.

Ecological Species Groups and Interspecific Association of Dominant Tree Species in Daiyun Mountain National Nature Reserve

Abstract： Research on the ecological species groups and interspecific association of plant species are helpful to discover species coexistence processes and mechanisms, and to more fully understand plant community structure, function, and its taxonomy. However, little is known about the ecological species groups （ESG） and the interspecific association of dominant species in Daiyun Mountain National Nature Reserve of Fujian Province, China. Therefore, the main goal of this paper is to explore the ESG using maximal tree, and to analyze interspecific associations of 32 dominant species selected from lo2 sample plots using the chi-square test. The results show that： （1） 32 dominant species have a significant overall positive interspecific association, which indicates that the natural forest in Daiyun Mountain National Nature Reserve is stable, （a） The species pairs with weak associations, non-associations and positive associations account for lo.88%, 29.64% and 59.48% of the total 496 species pairs respectively, which suggests that the population distributions of the dominant species investigated are relatively independent, （3） The following species pairs may be useful for practical application, 〈Pinus taiwanensis, Rhododendron farrerae〉, 〈Castanopsis carlesii, Altingia chinensis〉, 〈C. carlesii, Castanopsis fargesii〉, 〈Castanopsis eyrei, C. fargesii〉, 〈P. taiwanensis, Fagus lucida〉 , 〈Machilus thunbergii, Castanopsis nigrescens〉, and （4） The results of clustering analysis based on the maximal tree method indicates that the 32 dominant species can be divided into 3 ESGs when A at o.6o, that is ESG I {Pinus massoniana, Cunning hamia lanceolata}, ESG II {P. taiwanensis, R. farrerae, Enkianthus quinqueflorus}, ESG III {C. carlesii, A. chinensis, C. eyrei, Castanopsis fabri, C. fargesii, Schima superba, Machilus thunbergii, Rhododendron latoueheae}. The results may be used for the selection of afforestation tree species in South China Forest Areas and guide the natural management of plantations.

Ecological species groups and interspecific association of vegetation in natural recovery process at Xiejiadian landslide after 2008 Wenchuan earthquake

Wenchuan earthquake on 12 May 2008 triggered numerous landslides, which disturbed vast areas of vegetation in northwest Sichuan. However, based on our primary field investigation at Xiejiadian landslide in July 2009, we found an obvious increase of the number of plant species and then we made a hypothesis that, after earthquake, vegetation at this landslide might recover by itself. In this paper, we conduct a newly field investigation at Xiejiadian landslide during November 2014 to verify this hypothesis. We investigated plant species composition at total 56 sites(trees 4, shrubs 16 and herbs 36, respectively), and calculated the Schluter's variance ratio, important values, x2 test, associationcoefficient, Ochiai index, Pearson's and Spearman's correlation coefficients, and Ecological species groups. Species sharply increased to 84 species belonging to 66 genera and 54 families, forming a complete life form containing trees, shrubs, herbs, and ground layers while only herbs detected in 2009. Moreover, an overall positive and moderately related interspecies association was detected for most of species pairs. Of total 84 species, twenty five were identified as dominant species and could be divided into four positive ecological species groups. This study verified our proposed hypothesis of self-recovery of vegetation in landslide triggered by the earthquake, and found Alnus cremastogyne, Rhus chinensis, Litsea cubeba, Vitis piasezkii and Anemone vitifolia would play a constructive role during the continuing succession of vegetation at Xiejiadian landslide.

A New Brown Frog of the Genus Rana(Anura,Ranidae)from North China,with a Taxonomic Revision of the R.chensinensis Species Group

The Rana chensinensis species group is widely distributed throughout North China.However,its taxonomy and composition remain controversial.In recent field investigations of the Taihang Mountains,a series of Rana specimens were collected,which were once identified as R.chensinensis.However,these samples showed significant differences from R.chensinensis of the type locality(Shaanxi Province in the Qinling Mountains)in both morphology and genetics.In this paper,based on analyses of seventeen geographic populations from the Taihang and Qinling Mountains,we describe a new species(namely R.taihangensis sp.nov.)in the R.chensinensis species group.A phylogenetic analysis of the R.chensinensis species group based on mitochondrial genes—COI,16S rRNA and Cytb—revealed the monophyly of the cryptic species,which formed the sister taxon to R.kukunoris.Morphological comparisons indicated that the cryptic species can be distinguished from its congeners by a combination of characteristics.Additionally,the distribution patterns of the Rana species in North China were clarified.The populations of the southwestern Taihang Mountains,Xiaoqinling Mountains,and Funiu Mountains in Henan Province remain R.chensinensis,whereas the populations recorded as R.chensinensis in Beijing City,Hebei Province,and the southeastern Taihang Mountains of Henan Province should be revised as R.taihangensis sp.nov.

Phylogeography and Cryptic Species Diversity of Paramesotriton caudopunctatus Species Group(Salamandridae: Paramesotriton) in Guizhou, China

The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary relationships and divergence-time of members of this species group as a whole remain unexplored. In this study, we report the sequencing of one protein coding mitochondrial gene fragment(ND2) and one nuclear gene(POMC), and use a combination of phylogenetic analyses and coalescent simulations to explore the cryptic diversity and evolutionary history of the P. caudopunctatus species group. Phylogenetic relationships revealed that the P. caudopunctatus species group is composed of two major groups, i. e., East Clade and Western-South Clade. The divergence-time and ancestral area estimation suggested that the P. caudopunctatus species group likely originated in the Doupeng Mountains in Guizhou, China at 12.34 Ma(95% HPD: 8.30–14.73), and intraspecific divergence began at about 2.17 Ma(95% HPD: 1.39–2.97). This timing coincides with the orogenesis of the Miaoling Mountains during the Late Miocene to early Pleistocene. The delimitation of species in the P. caudopunctatus species group supports the existence of the currently identified species, and consensus was confirmed across methods for the existence of least to two cryptic species within what has been traditionally considered to be P. caudopunctatus species group. This study is of significance for understanding the species formation, dispersal, and diversity of the tailed amphibians in the karst mountains ecosystem of Guizhou and the role of the Miaoling Mountains as a geographical barrier to species dispersal.

Developing allometric equations to estimate forest biomass for tree species categories based on phylogenetic relationships

The development of allometric biomass models is important process in biomass estimation because the reliability of forest biomass and carbon estimations largely depends on the accuracy and precision of such models.National Forest Inventories(NFI)are detailed assessments of forest resources at national and regional levels that provide valuable data for forest biomass estimation.However,the lack of biomass allometric equations for each tree species in the NFI currently hampers the estimation of national-scale forest biomass.The main objective of this study was to develop allometric biomass regression equations for each tree species in the NFI of China based on limited biomass observations.These equations optimally grouped NFI and biomass observation species according to their phylogenetic relationships.Significant phylogenetic signals demonstrated phylogenetic conservation of the crown-to-stem biomass ratio.Based on phylogenetic relationships,we grouped and matched NFI and biomass observation species into 22 categories.Allometric biomass regression models were developed for each of these 22 species categories,and the models performed successfully(R^(2)=0.97,root mean square error(RMSE)=12.9​t·ha^(–1),relative RMSE=11.5%).Furthermore,we found that phylogeny-based models performed more effectively than wood density-based models.The results suggest that grouping species based on their phylogenetic relationships is a reliable approach for the development and selection of accurate allometric equations.

Description of a New Species of Amolops (Anura:Ranidae) from Tibet,China

A new species,Amolops pallasitatus sp.nov.is described based on specimens collected from Chentang Town,Dinggyê County,southern Tibet,China.The new species can be distinguished from other known congeners by mitochondrial divergence and morphological characteristics including:(1)medium body size,SVL 70.6–72.3 mm in adult females;(2)skin smooth over the entire body;(3)absence of dorsolateral fold;(4)tympanum small,edge indistinct,less than half of eye diameter;(5)vomerine teeth in two short oblique;(6)circummarginal and transverse grooves absent on disk of the first finger;(7)presence of inner metacarpal tubercle;(8)toes fully webbed,webbing formula Ⅰ0-0^-Ⅱ0-1/2Ⅲ0-1^+Ⅳ1^+-0Ⅴ;(9)absence of outer metatarsal tubercle and tarsal glands;(10)tibiotarsal articulation of the hind limb reaches posterior corners of the eye;(11)dorsum yellow-green,with irregular dark brown blotches without margins;(12)blotches concentrated on the dorsum,less on the flanks.In morphology,Amolops pallasitatus sp.nov.is similar to A.himalayanus and A.formosus,the difference between them is length of hind limbs,web of toe and dorsal colour pattern.The systematic placement of the new species within the genus is unresolved and it is not assigned to any recognized species group,for the lack of convictive evidences.

A taxonomic review of the genus Stenolechia Meyrick(Lepidoptera:Gelechiidae:Litini)from China,with descriptions of three new species

Species of Stenolechia Meyrick,1894 from China are reviewed,including three new species:Stenolechia longivalva sp.nov.,Stenolechia curvativalva sp.nov.and Stenolechia cuneata sp.nov.,and three new records to China:Stenolechia kodamai Okada,1962,Stenolechia insulalis Park,2016 and Stenolechia notomochla Meyrick,1935.The previously unknown female of Stenolechia insulalis Park,2016 is described.Photographs of adults and genitalia are provided,along with two keys to the Chinese species based on the male and female genitalia.

Three new species and a new record species of the genus Homoneura(Diptera:Lauxaniidae) from the Qinling Mountains, China

Three species from the Qinling Mountains are described as new to science: Homoneura(Homoneura) fopingensis Gao & Shi sp. nov. in the H.(H.) quinquenotata group, and H.(H.) aliena Gao & Shi sp. nov. and H.(H.) heilongtanensis Gao & Shi sp. nov. in the H.(H.) sauteri group. H.(H.) stigmata Papp, 1984 in the H.(H.) quinquenotata group is recorded from China for the first time. The diagnosis of two species groups is presented. Keys to divide these two species groups and separate known species from the new species are provided.

DNA Barcoding and Systematic Review of Minervaryan Frogs(Dicroglossidae:Minervarya) of Peninsular India:Resolution of a Taxonomic Conundrum with Description of a New Species

The genus Minervarya is among the most widely distributed,commonly occurring,and taxonomically confusing groups of dicroglossid frogs in India.Recent studies have provided evidence that this genus contains complexes of morphologically conserved but genetically divergent taxa—some widely distributed across South and Southeast Asia,and many particularly restricted to the Western Ghats region of the Indian Peninsula—posing several challenges in resolving long-standing taxonomic confusions.Here,we present a systematic review of minervaryan species found in Peninsular India,based on extensive DNA barcoding with nearly 400 samples from the entire range of the genus,including 277 new samples and topotypic material for most available names from the study area,combined with detailed morphological studies.As a result,we recognise 18 species in Peninsular India,including a new species described herein as Minervarya pentali sp.nov.Due to the comprehensive nature of the study,including comparisons with all available types,certain long-standing taxonomic uncertainties on the status of ten previously known taxa are resolved Rana(Tomopterna)parambikulamana Rao,1937(=Minervarya parambikulamana),Rana(Hylorana)sauriceps Rao,1937(=Minervarya sauriceps),and Fejervarya kudremukhensis Kuramoto,Joshy,Kurabayashi,and Sumida,2008"2007"(=Minervarya kudremukhensis),are considered as junior subjective synonyms of Rana(Rana)limnocharis mysorensis Rao,1922(=Minervarya mysorensis);Nyctibatrachus sanctipdustris var.modestus Rao,1920(=Minervarya modesta)is proposed to be a synonym of Rana limnocharis syhadrensis Annandale,1919(=Minervarya syhadrensis);while Rana murthii Pillai,1979(=Minervarya murthii)and Fejervarya mudduraja Kuramoto,Joshy,Kurabayashi,and Sumida,2008"2007"(=Minervarya mudduraja)are considered as junior subjective synonyms of Rana nilagirica Jerdon,1853(=Minervarya nilagirica).At the same time,Rana brevipalmata Peters,1871(=Minervarya brevipalmata),previously known only from its original description and the type specimen,is recognised as a distinct species referable to live populations in the Western Ghats.The study results in taxonomic stability of all the currently recognised members of the genus in Peninsular India.Significant geographical range extensions of species previously known from single localities are also provided based on morphologically and genetically confirmed records.Additionally,we classify all the recognised species into eight species-groups,with the aim of facilitating a better working taxonomy and future systematic studies on minervaryan frogs across their entire known range in Asia.

A TAXONOMIC STUDY ON COENOSIA TIGRINA SPECIES-GROUP(DIPTERA: MUSCIDAE) IN CHINA

The Chinese species of Coenosia tigrina species-group of the genus Coenosia Meigen, 1826 are treated . One new species, C.albisquama sp.nov., and two new subspecies, C. attenuata brunnea subsp.nov. and C. strigipes bannaensis subsp. nov., are described. A key to Chinese species is given to seperate the species. The types specimens are deposited in the Institute of Entomology, Shenyang Normal University.

Impact of summer moratorium on set-net fi shery in Haizhou Bay,China

The set-net fi shery resources in Haizhou Bay,China have been over-exploited because of over-fi shing and environmental deterioration.To better understand the current situations and the development trends of fi shery resources,the temporal change of biological characteristics and community compositions were analyzed from 2011 to 2018.Meanwhile,we evaluated the impact of the summer moratorium of marine fi shing(SMMF)on the set-net fi shery.Results show that the mean total length of the six principal species showed varying degrees of decreasing trends,while the changing patterns for the mean weight proportion of the six groups varied.For the whole communities,the similarities of the inter-annual community diversities and compositions were high.SMMF is meaningful to help reproductive success and support recruitment.Every year,the catch per unit eff orts of the six principal species after SMMF were signifi cantly higher than before SMMF except for Octopus ocellatus.The target groups showed a higher mean weight proportion after SMMF than before SMMF in eight years,while the non-target groups were converse.Therefore,the resources of the set-net fi shery are changing in the study periods;and SMMF is an important factor infl uencing biological characteristics and community structure.Despite some challenges,SMMF is still one of the most appropriate policy tools to protect the set-net fi shery resources under the reality of China.

Predicting the dynamics of a native Araucaria forest using a distance- independent individual tree-growth model

Background： In recent decades, native Araucaria forests in Brazil have become fragmented due to the conversion of forest to agricultural lands and commercial tree plantations. Consequently, the forest dynamics in this forest type have been poorly investigated, as most fragments are poorly structured in terms of tree size and diversity. Methods; We developed a distance-independent individual tree-growth model to simulate the forest dynamics in a native Araucaria forest located predominantly in southern Brazil. The data were derived from 25 contiguous plots （1 ha） established in a protected area left undisturbed for the past 70 years. The plots were measured at 3-year intervals from their establishment in 2002. All trees above a l O-cm diameter at breast height were tagged, identified as to species, and measured. Because this forest type comprises hundreds of tree species, we clustered them into six ecological groups： understory, subcanopy, upper canopy shade-tolerant, upper canopy light-demanding, pioneer, and emergent. The diameter increment, survival, and recruitment sub-models were fitted for each species group, and parameters were implemented in a simulation software to project the forest dynamics. The growth model was validated using independent data collected from another research area of the same forest type. To simulate the forest dynamics, we projected the species group and stand basal areas for 50 years under three different stand-density conditions： low, average, and high. Results： Emergent species tended to grow in basal area, irrespective of the forest density conditions. Conversely, shade-tolerant species tended to decline over the years. Under low-density conditions, the model showed a growth tendency for the stand basal area, while under average-density conditions, forest growth tended to stabilize within 30 years. Under high-density conditions, the model indicated a decline in the stand basal area from the onset of the simulation, suggesting that under these conditions, the forest has already reached its maximum-stock capacity. Conclusions： The model validation using independent data indicated close agreement between the observed and estimated values, suggesting the model is consistent in projecting species-group and stand growth. The methodology used in this study for developing the growth model should be tested in other species-rich forests.

Species composition and correlation of understory woody plants in Chinese fir plantation in the lower subtropical area

There are 71 species in the shrub layer of the Cunninghamia lanceolata plantation after natural succession.The species richness and diversity have increased with slight anthropogenic disturbance.The status and function of understory woody species were judged by the analysis of the important value(IV).χ2 statistics and r test were used for testing the significance of interspecific association and correlation among 25 main understory woody plants selected from the woody population.The results clearly showed their interspecific relationships and their differences in resource utilization.Species-pairs of positive association were in the majority.Most species were accommodated in the shady habitat.There was a positive correlation between the IV of the species and the interspecific association.The higher the IV of the species,the closer and more significant was the interspecific association.Based on analytical results of interspecific association and correlation,25 woody plants in the shrub layer could be divided into four ecological species groups:I.Ficus hispida+Antidesma bunius+Mallotus barbatus+Ficus cunia+Saurauia tristyla+Mallotus philippinensis+Maesa japonica+Ficus hirta+Alchornea rugosa+Ficus fulva+Mallotus apelta;II.Cudrania tricuspidata+Schefflera octophylla;III.Cunninghamia lanceolata+Clerodendron cytophyllum+Millettia semicastrata+Randia spinosa+Litsea cubeba+Litsea pungens;IV.Ardisia japonica+Psychotria rubra+Vitex quinata+Cephalanthus occidentalis+Pithecellobium lucidum+Mycetia sinensis.If species group III or II is the advantaged species in the shrub layer,the community would change from a coniferous forest to a sparse evergreen broad-leaved forest.For group IV,the community would be relatively stable.For group I,the coniferous forest would be mixed with coniferous-broad leaved forest.The classification of ecological species groups would provide a theoretical basis on judging its ecological function,adjusting the stand structure of the plantation and directing the suitable natural vegetation type through the close-natural restoration process.

Current status of greenhouse gas emissions from aquaculture in China

Aquaculture and mariculture are becoming an increasingly important source of food supply in many countries and regions.However,with the expansion of aquaculture and mariculture comes increasing emissions of greenhouse gases(GHG)which contribute to global warming and climate change.China leads the world in aquaculture and mariculture production,but there are no studies that systematically assess China's overall carbon footprint from these industries.This study quantified GHG emissions from aquaculture and mariculture by four source phases(feed,energy use,nitrous oxide and fertilizers),and then analyzed the carbon footprint of each of these phases for GHG production of nine major species groups over the past ten years to show the spatial distribution of GHG emissions from aquaculture and mariculture in China.Our results showed that the production of feed materials contributed most to the GHG emissions and found that crop energy use,crop land use changes(LUC),fertilizer production,crop nitrous oxide production and rice methane production were the main sources of feed emissions.The total GHG emissions of the nine species groups were 112 Mt(10^(9) kg)CO_(2)e,the nine species accounting for approximately 86%of aquaculture and mariculture production.GHG emissions of cyprinids had the highest contribution at 47%.Spatial analysis based on our study showed Guangdong,Hubei,Jiangsu and Shandong had the highest GHG emissions of all the provinces in this study,and they accounted for approximately 46%of all emissions.The regional Gross Domestic Product(GDP)was significantly positively correlated with GHG emissions in every province,with a correlation coefficient higher than 0.6.Our results showed for the first time the relationship between the relative production by species composition and spatial distribution of GHG emissions from aquaculture and mariculture in China.Our findings provide the scientific basis for reduction of GHG emissions within a broader context of expanding aquaculture in the future.

Identification of characteristic plant co-occurrences in neotropical secondary montane forests

Aims Inferring environmental conditions from characteristic patterns of plant co-occurrences can be crucial for the development of conservation strategies concerning secondary neotropical forests.However,nomethodological agreement has been achieved so far regarding the identification and classification of characteristic groups of vascular plant species in the tropics.This study examines botanical and,in particular,statistical aspects to beconsidered in such analyses.Based on these,we propose a novel data-driven approach for the identification of characteristic plantco-oc currences in neotropical secondary mountain forests.Methods Floristic inventory data were gathered in secondary tropical mountain forests in Ecuador.Vegetation classification was performed by coupling locally adaptive isometric feature mapping,a non-linear ordination method and fuzzy-c-means clustering.This approach was designed for dealing with underlying non-linearities and uncertainties in the inventory data.Important Findings The results indicate that the applied non-linear mapping in combination with fuzzy classification of species occurrence allows an effective identification of characteristic groups of co-occurring species as fuzzy-defined clusters.The selected species indicated groups representing characteristic life-form distributions,as they correspond to various stages of forest regeneration.Combining the identified‘characteristic species groups’with meta-information derived from accompanying studies indicated that the clusters can also be related to habitat conditions.In conclusion,we identified species groups either characteristic of different stages of forest succession after clear-cutting or of impact by fire or a landslide.We expect that the proposed data-mining method will be useful for vegetation classification where no a priori knowledge is available.