Taxonomic Relationships Research Articles

Complicated family relationships, or about taxonomic problems in the family Pyrenomonadaceae (Cryptophyceae)

Cryptophytes, to which the Pyrenomonadaceae family belongs, are interesting organisms that occur almost all over the world and they are an important element of trophic chains in many ecosystems. The development of research methods and techniques, including electron microscopy and molecular studies, allowed for a better understanding of taxonomic relationships in this group of organisms. The Pyrenomonadaceae family currently includes three genera: Rhodomonas, Rhinomonas, and Storeatula, but their validity is being debated in the light of the latest data. The state of knowledge and the problems faced in the taxonomic revision of this family of cryptophytes are summarized in this article.

Pollen morphology of Ipomoea L. from Garhwal Himalaya, India

Pollen morphology serves as a valuable tool for identification, phylogenetic analysis and evolutionary studies. The present study aims to investigate the pollen morphology of 12 species of the genus Ipomoea L. (a diverse and economically important genus within the family Convolvulaceae) from Garhwal Himalaya, India. Fresh flower buds were collected from the study area and pollen preparation completed using the acetolysis method. The morphology of the pollen grains were examined using light microscopy and scanning electron microscopy. Pollen grains of all the studied species were apolar, spheroidal, pantoporate, subtectate with fine reticulation and echinate, but they differed from one another in their size, number of spines and pores, spine length and spine types. The size of grains ranged from 53.3 to 128.7 μm. Cluster analysis was performed based on pollen characters to show the relationship among the species; a key was prepared and is discussed. The observed variation in pollen morphological traits gives important taxonomic information that is useful for distinguishing Ipomoea species and establishing taxonomic and phylogenetic relationships.

Pollen Morphology in Sorbus L. (Rosaceae) and Its Taxonomic Implications.

The genus Sorbus L. in the Rosaceae family is taxonomically challenging due to its morphological variation, polyploidy, and interspecific hybridization. In this study, we used scanning electron microscopy (SEM) to observe the pollen morphology of eighty species, representing six subgenera, in order to assess the differences within the genus Sorbus and its pollen characteristics. We conducted a cluster analysis on three qualitative and four quantitative characteristics. The results demonstrated that the pollen grains of the studied Sorbus species are isopolar and tricolporate. We identified five types of pollen shapes: suboblate, spheroidal, subprolate, prolate, and perprolate. The pollen ornamentation of the investigated species could be classified into five types: striate-perforate, striate, cerebroid-perforate, cerebroid, and foveolate. Interestingly, within the same subgenera, different species exhibited multiple types of characters. The cluster analysis indicated that all 80 species could be divided into six groups, with group B consisting exclusively of species from the subgenus Sorbus. Although pollen micro-morphologies alone do not provide sufficient evidence to establish the taxonomic relationships of the subgenera within Sorbus, they do offer valuable information for species-level taxonomic treatment.

Reclassification of Streptomyces griseostramineus as a synonym of Streptomyces griseomycini based on a polyphasic taxonomic approach.

In the present work, the taxonomic relationship between Streptomyces griseomycini and Streptomyces griseostramineus was reevaluated by a comprehensive comparison of phenotypic, chemotaxonomic and genomic characteristics, as well as phylogeny. Phylogenetic analysis based on 16S rRNA gene sequences and whole-genome sequences indicated that Streptomyces griseostramineus JCM 4385T was clustered together with Streptomyces griseomycini JCM 4382T, suggesting they were closely related to each other. However, the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between their genomes were 99.7 and 97.5 %, respectively, much larger than the recommended threshold values of 96.7 % ANI and 70 % dDDH for Streptomyces species delineation. In addition, the morphological, cultural, physio-biochemical and chemotaxonomic features of these two species further demonstrated that they belonged to the same genome species. Based on the above data and the principle of priority in nomenclature, it is proposed that S. griseostramineus (Preobrazhenskaya et al. 1957) Pridham et al. 1958 (Approved Lists 1980) is a later heterotypic synonym of S. griseomycini (Preobrazhenskaya et al. 1957) Pridham et al. 1958 (Approved Lists 1980).

Host-specific adaptation drove the coevolution of leek yellow stripe virus and Allium plants.

Host adaptation plays a crucial role in virus evolution and is a consequence of long-term interactions between virus and host in a complex arms race between host RNA silencing and viral RNA silencing suppressor (RSS) as counterdefense. Leek yellow stripe virus (LYSV), a potyvirus causing yield loss of garlic, infects several species of Allium plants. The unexpected discovery of an interspecific hybrid of garlic, leek, and great-headed (GH) garlic motivated us to explore the host-adaptive evolution of LYSV. Here, using Bayesian phylogenetic comparative methods and a functional assay of viral RSS activity, we show that the evolutionary context of LYSV has been shaped by the host adaptation of the virus during its coevolution with Allium plants. Our phylogenetic analysis revealed that LYSV isolates from leek and their taxonomic relatives (Allium ampeloprasum complex; AAC) formed a distinct monophyletic clade separate from garlic isolates and are likely to be uniquely adapted to AAC. Our comparative studies on viral accumulation indicated that LYSV accumulated at a low level in leek, whereas LYSVs were abundant in other Allium species such as garlic and its relatives. When RSS activity of the viral P1 and HC-Pro of leek LYSV isolate was analyzed, significant synergism in RSS activity between the two proteins was observed in leek but not in other species, suggesting that viral RSS activity may be important for the viral host-specific adaptation. We thus consider that LYSV may have undergone host-specific evolution at least in leek, which must be driven by speciation of its Allium hosts. IMPORTANCE Potyviruses are the most abundant plant RNA viruses and are extremely diversified in terms of their wide host range. Due to frequent host switching during their evolution, host-specific adaptation of potyviruses may have been shaped by numerous host factors. However, any critical determinants for viral host range remain largely unknown, possibly because of the repeated gain and loss of virus infectivity of plants. Leek yellow stripe virus (LYSV) is a species of the genus Potyvirus, which has a relatively narrow host range, generally limited to hosts in the genus Allium. Our investigations on leek and leek relatives (Allium ampeloprasum complex), which must have been generated through interspecies hybridization, revealed that LYSV accumulation remained low in leek as a result of viral host adaptation in competition with host resistance such as RNA silencing. This study presents LYSV as an ideal model to study the process of host-adaptive evolution and virus-host coevolution.

Morphology, Histology, and Cytology of the Testis and Accessory Glands of Bolua turkiyae (Orthoptera, Tettigoniidae)

There are many morphological and histological studies in the world to investigate the structure of the external and internal organs of insects. These studies not only serve to illuminate the biology of insect species, but also to reveal taxonomic relationships. For this purpose, the detailed structure of the testis and accessory glands that are the main organs of the male reproductive system of Bolua turkiyae Ünal, 1999 (Orthoptera: Tettigoniidae) was searched with a light microscope, scanning electron microscope, and transmission electron microscope techniques in 2019-2020 in Gazi University, Prof. Dr. Zekiye Suludere Electron Microscope Center in this study. B. turkiyae is an endemic species distributed around Bolu province in Turkey. The reproductive system of male B. turkiyae is comprised of testis, vas deferens, and accessory glands. When the cross-sections of the oval and yellow testis were examined, it was observed that they contain many follicles. There are cysts in these follicles that have the developmental stages of the sperm. From the distal ends of the follicles to the proximal ends, the germarium, growth zone, maturation zone, and transformation zone are located respectively. In these stages, spermatogonium, spermatocyte, spermatids, and finally spermatozoa are formed. Accessory glands are hollow tubular structures of two different sizes and diameters. Single-layered cubic or pyramidal cells surround the lumen in both groups of accessory glands. It is hoped that these new data will contribute to our understanding of the structure of the male reproductive system of B. turkiyae.

Comparative mitogenomic analysis confirms that the southern African long-snout pipefish Syngnathus temminckii is distinct from the northern hemisphere Syngnathus acus

Sequencing of mitochondrial genomes is a powerful tool to resolve taxonomic relationships between closely related taxa with high confidence. Syngnathus temminckii is a pipefish species endemic to Southern Africa. The taxonomic status of this species and the phylogenetic relationship with its widely distributed northern hemisphere congener Syngnathus acus has been subject to uncertainty. The current study is the first to assemble, annotate and describe the complete mitochondrial genome of this species, and investigate phylogenetic relationships with its northern hemisphere sister taxa. The mitogenome assembly pipeline reconstructed a circular contig 16,452 bp in length, with an average GC content of 44.8%. A total of 37 mitogenomic features, including 13 protein-coding genes, 22 tRNAs, two rRNAs and a putative control region, were annotated. A Bayesian phylogenetic analysis confirmed that S. temminckii is a distinct southern African species that diverged from a northern hemisphere clade of pipefishes that includes its congener S. acus approximately seven million years ago.

Model of Taxonomy for Accessibility Ontology

Digital accessibility to educational and informational resources for people with disabilities is an important part of contemporary life. Semantic organization of knowledge in the domain of accessibility provides a convenient way of extracting and organizing data. The paper focuses on semantic design techniques and related taxonomy models that could be used in the digitization process of resources intended of people with disabilities usage.

The Holocene record of the slow loris (Nycticebus sp.) in Java (Indonesia).

(Sub)fossil lorises are rare in Southeast Asia. Their taxonomic relationship with extant populations, and the extent to which their distribution and morphology are influenced by changing environmental conditions, remains poorly understood. This study provides a synthesis of Nycticebus occurrences in Holocene Java. A morphometric analysis of a sample of craniodental remains aims to improve our understanding of their taxonomic status. Morphometrics were also used to explore potential size changes during the Holocene. Based on the literature and a review of museum catalogs, a synthesis was compiled of (sub)fossil slow loris occurrences in Java. Morphometric data on the mandible and maxilla of 10 (sub)fossil lorises were compared with a dataset of extant specimens to assess variation in size and shape. Five Holocene Nycticebus occurrences were identified in eastern Java. All specimens fall in the range of N. javanicus and N. coucang. The specimens from Hoekgrot, Gua Jimbe, and Sampung suggest an affinity to N. javanicus. The remains from Gua Jimbe and Hoekgrot gave values close to the largest N. javanicus specimens, but the (presumably older) Song Terus specimen was of average size. The distribution of Nycticebus suggests that it originally occurred throughout the island. The remains are probably best identified as N. javanicus or N. coucang, but the Neolithic finds from Hoekgrot and Gua Jimbe are presumably N. javanicus. Size variation in Nycticebus was clinal, but although some large specimens were present, no evidence was found for size diminution during the Holocene.

Three new taxa and two noteworthy species of Peliosanthes (Asparagaceae, Convallarioideae) from Laos and Vietnam

Two new species, Peliosanthes annamensis and P. virescens from Dak Lak Province in southern Vietnam, are described and illustrated. The former is morphologically similar to P. crassicoronata, while the latter to P. argenteostriata. We also describe and illustrate one new variety, P. nivea var. acutiloba from Khammouane Province, central Laos. Peliosanthes divaricatanthera, formerly known from central Vietnam (Da Nang City) and SW China (Yunnan), was rediscovered in southern Vietnam (Dak Lak Province). Its illustrations and amended description based on new materials are provided. We also report P. micrantha, so far known from central and southernVietnam, as a new addition to the flora of Laos. Notes on their morphological and ecological aspects, taxonomic relationships to the respective congeners, and data on their habitats are provided as well.

Genome-wide and constrained ordination-based analyses of EC code data support reclassification of the species of Massilia La Scola et al. 2000 into Telluria Bowman et al. 1993, Mokoshia gen. nov. and Zemynaea gen. nov.

Based on genome-wide data, Massilia species belonging to the clade including Telluria mixta LMG 11547T should be entirely transferred to the genus Telluria owing to the nomenclatural priority of the type species Telluria mixta. This results in the transfer of 35 Massilia species to the genus Telluria. The presented data also supports the creation of two new genera since peripherally branching Massilia species are distinct from Telluria and other related genera. It is proposed that 13 Massilia species are transferred to Mokoshia gen. nov. with the type species designated Mokoshia eurypsychrophila comb. nov. The species Massilia arenosa is proposed to belong to the genus Zemynaea gen. nov. as the type species Zemynaea arenosa comb. nov. The genome-wide analysis was well supported by canonical ordination analysis of Enzyme Commission (EC) codes annotated from genomes via pannzer2. This new approach was performed to assess the conclusions of the genome-based data and reduce possible ambiguity in the taxonomic decision making. Cross-validation of EC code data compared within canonical plots validated the reclassifications and correctly visualized the expected genus-level taxonomic relationships. The approach is complementary to genome-wide methodology and could be used for testing sequence alignment based data across genetically related genera. In addition to the proposed broader reclassifications, invalidly described species 'Massilia antibiotica', 'Massilia aromaticivorans', 'Massilia cellulosiltytica' and 'Massilia humi' are described as Telluria antibiotica sp. nov., Telluria aromaticivorans sp. nov., Telluria cellulosilytica sp. nov. and Pseudoduganella humi sp. nov., respectively. In addition, Telluria chitinolytica is reclassified as Pseudoduganella chitinolytica comb. nov. The use of combined genome-wide and annotation descriptors compared using canonical ordination clarifies the taxonomy of Telluria and its sibling genera and provides another way to evaluate complex taxonomic data.

Faecalibacterium hominis Liu et al. 2023 is a later heterotypic synonym of Faecalibacterium duncaniae Sakamoto et al. 2022.

A strain of the recently validated species Faecalibacterium hominis shares 99.0 % 16S rRNA gene sequence similarity with the type strain of Faecalibacterium duncaniae. The aim of this study was to evaluate the taxonomic relationship between F. hominis and F. duncaniae. F. duncaniae JCM 31915T showed 73.0 % digital DNA-DNA hybridization (dDDH) value with F. hominis JCM 39347T. The average nucleotide identity (ANI) value between these two strains was 96.7 %. These results indicate that F. duncaniae JCM 31915T and F. hominis JCM 39347T represent members of the same species. Based on these data, we propose Faecalibacterium hominis as a later heterotypic synonym of Faecalibacterium duncaniae. An emended description is provided.

Palynology of Philippine Amorphophallus Blume ex Decne. (Araceae) and its taxonomic implications

Abstract. Fontarum-Bulawin NF, Medecilo-Guiang MMP, Calaramo MA, Alejandro GJD. 2023. Palynology of Philippine Amorphophallus Blume ex Decne. (Araceae) and its taxonomic implications. Biodiversitas 24: 4095-4109. Amorphophallus is one of the genera of Araceae with diverse pollen characters. This study aimed to investigate the pollen morphological characters of Amorphophallus in the Philippines for inferring taxonomical relationships. Light microscopy (LM) and scanning electron microscopy (SEM) were employed to investigate pollen morphology of 14 accessions of Amorphophallus. Both acetolyzed and unacetolyzed pollens were studied to compare the outward aspect of pollens and the pollen characters were subjected to cluster analysis. Results revealed that pollen grains were mostly spheroidal, prolate-spheroidal, and subspheroidal in shape. The pollen sizes vary from 3.0 to 50 µm and exhibit very small to medium sizes. The ornamentations of unacetolyzed pollens were psilate and striate, whereas ornamentations in acetolyzed pollens are varied from psilate, rugulate, rugulate hamulate, reticulate, scabrate, striateto verrucate ornamentations. All pollens were inaperturate and monad. Cluster analysis using Euclidean generated 2 major clusters, namely Cluster I consists of Amorphophallus adamsensis Magtoto, Mones, Ballada, Austria, R.M.Dizon, Alangui, Regina, Amorphophallus sp.3 (Samar), Amorphophallus yaoi A.Galloway, Hett. & Medecilo, Amorphophallus flammeus Calaramo, Batuyong, Bulawin & Alejandro, Amorphophallus urceolatus Hett. et al. (Ilocos), Amorphophallus rayongii Hett. & Medecilo, Amorphophallus sp.2 (Romblon), and Amorphophallus urceolatus Hett., A.Galloway & Medecilo (Cavite); and cluster 2 consists of Amorphophallus paeoniifolius (Dennst.) Nicolson, Amorphophallus fontarumii Bulawin, Medecilo & Alejandro, Amorphophallus rostratus Hett., Amorphophallus longispathaceus Engl.& Gehrm., and Amorphophallus sp.1 Based on this study, pollen shape, size, and ornamentation can be used as supplemental characters for the taxonomic identification of Amorphophallus in the Philippines.

Life Cycle Plasticity in Typhula and Pistillaria in the Arctic and the Temperate Zone.

Typhulaceae Jülich is one of the cold-adapted fungal families in basidiomycetes. The representative genera, Typhula (Pers.) Fr. and Pistillaria Fr., are distinguished by the discontinuity between stems and hymenia in the former and the continuity in the latter (Fries 1821). This taxonomic criterion is ambiguous, and consequently, the view of Karsten (1882) has been widely accepted: Typhula develops basidiomata from sclerotia, while basidiomata develop directly from substrata in Pistillaris. However, Corner (1970) observed basidiomata of Pistillaria petasitis S. Imai developing from sclerotia in Hokkaido, Japan. We later recognized that P. petasitis basidiomata also emerged directly from substrates on the ground in Hokkaido. An aberrant form of Typhula hyperborea H. Ekstr. was found in Upernavik, West Greenland. This specimen had a stem-like structure on a Poaceae plant, and sclerotia developed on its tip. Similar phenomena were found in other Typhula species in Japan. In this study, we aimed to elucidate the life cycle plasticity in the genera Typhula and Pistillaria through the interactions between their ecophysiological potential and environmental conditions in their localities. We collected and prepared strains of the above fungi from sclerotia or basidiomata, and we elucidated the taxonomical relationship and determined the physiological characteristics of our strains. Our findings imply that both Typhula and Pistillaria have the potential to produce sclerotia as well as the capacity for mycelial growth at ambient air temperatures in each locality where samples were collected. These findings suggest that Typhula spp. develope basidiomata not only from the sclerotia dispersed by the basidiospores but also from mycelia generated by the spore germination, which formed basidiomata multiple times, depending on their growth environments.

Application of High-Resolution Melting and DNA Barcoding for Discrimination and Taxonomy Definition of Rocket Salad (Diplotaxis spp.) Species.

Nuclear and cytoplasmic DNA barcoding regions are useful for plant identification, breeding, and phylogenesis. In this study, the genetic diversity of 17 Diplotaxis species, was investigated with 5 barcode markers. The allelic variation was based on the sequences of chloroplast DNA markers including the spacer between trnL and trnF and tRNA-Phe gene (trnL-F), the rubisco (rbcl), the maturase K (matk), as well as the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA. A highly polymorphic marker (HRM500) derived from a comparison of cytoplasmic genome sequences in Brassicaceae, was also included. Subsequently, a real-time PCR method coupled with HRM analysis was implemented to better resolve taxonomic relationships and identify assays suitable for species identification. Integration of the five barcode regions revealed a grouping of the species according to the common chromosomal set number. Clusters including species with n = 11 (D. duveryrieriana or cretacea, D. tenuifolia, D. simplex and D. acris), n = 8 (D. ibicensis, D. brevisiliqua and D. ilorcitana), and n = 9 (D. brachycarpa, D. virgata, D. assurgens, and D. berthautii) chromosomes were identified. Both phylogenetic analysis and the genetic structure of the collection identified D. siifolia as the most distant species. Previous studies emphasized this species' extremely high glucosinolate content, particularly for glucobrassicin. High-resolution melting analysis showed specific curve patterns useful for the discrimination of the species, thus determining ITS1 as the best barcode for fingerprinting. Findings demonstrate that the approach used in this study is effective for taxa investigations and genetic diversity studies.

Taxonomic and stratigraphic remarks on Placites urlichsi Bizzarini, Pompeckjites layeri (Hauer), Carnites floridus (Wulfen) and Sageceras haidingeri (Hauer)

Investigations of an Lower Carnian Wettersteinkalk ammonoid fauna found in the Hochobir massif (Carinthia/Austria) gave rise to problems in the taxonomic relationship within the Triassic ammonoid Family Pinacoceratidae. The morphological parameters of the ammonoid genus Pompeckjites are rather unclear. Morphological variation of at least two ammonoid species as Pompeckjites layeri Hauer on one end, Placites urlichsi Bizzarini on the other end have to be take into account. Numerous field surveys, studies and excavations on upper Wettersteinkalk sites within the Karavank Mountains and Hallstatt-facies sites in the Northern Calcareous Alps were implemented and compared with the reference sites in the Dolomites. As a consequence of our investigations, the Hochobir Wettersteinkalk ammonite assemblage is thought to be equivalent in time to the ammonoid fauna of the Upper San Cassian Formation. The frequent occurrence of the Julian (Lower Carnian) ammonoid Placites urlichsi Bizzarini may be a powerful tool in field investigations for a refined correlation of the upper Wettersteinkalk reef limestone to the coeval basinal facies of the Upper San Cassian Formation (Lower Carnian/upper Trachyceras aonoides Zone). As a result of this study Placites urlichsi was included in the genus Pompeckjites. This paper could be an attempt to recognize the differences in juvenile forms of Pompeckjites layeri and Placites urlichsi and other similar disciform ammonoid genera like Carnites floridus and Sageceras sp. based on suture lines, polished transversal-sections and morphological features.

Ottia, a new ennomine genus of moth from Tajikistan (Lepidoptera: Geometridae).

An ennomine species, described earlier as Plagodis ochraceata Viidalepp, 1988, is transferred from Plagodis Hbner, [1823]1816 to a genus of its own: Ottia ochraceata (Viidalepp, 1988) (gen. nov., comb. nov.). The morphology of the adult moth, of its male and female genitalia, phenology and spatial distribution are described and its taxonomic relationships are analyzed.

Phylogenetic, cytogenetic and morphological evidences are critical for recognizing a new genus: Valdesiana, an Iberian intergeneric allopolyploid between Schenkia and Exaculum

The present taxonomic status of Schenkia elegans, endemism recently described in the Iberian Peninsula, and its relationship with the sympatric and the nearest morphological species Schenkia spicata and Exaculum pusillum is revaluated. Different kinds of evidence based on plant morphology, ploidy estimation by flow cytometry, karyotype characterisation, and phylogenetic data have been analysed. Two maternally inherited plastid DNA regions (trnL intron and trnL-F spacer) and biparentally inherited nuclear ribosomal DNA sequence region (nrDNA ITS) have been used. Comparative multivariate analyses show an intermediate morphology of the S. elegans plants between the other two species studied. Flow cytometry and karyotype analyses in S. elegans point to an allopolyploid origin, with the latter constituted by a mixture of those of the diploids S. spicata and E. pusillum. Phylogenetic analyses based on plastid and nuclear DNA regions cluster S. elegans in two different clades, those of S. spicata and E. pusillum, suggesting a possible hybrid origin of S. elegans between both species, acting as maternal or paternal progenitors. In consequence, taking in consideration the taxonomic relationships among genera (Exaculum, Schenkia and the closely related genus Zeltnera found in America), a monotypic genus Valdesiana gen. nov. is proposed to accommodate the allopolyploid species, combined as V. elegans, for which immediate conservation measures must be evaluated.

Phylogenetic and taxonomic relationships between morphotypes related to Elymus caninus (Poaceae) based on sequence of a nuclear gene GBSS1 (waxy) and sexual hybridization

AbstractWe represent a comparative analysis of GBSS1 gene fragment sequences for a number of species related to Elymus caninus: Elymus prokudinii, Elymus viridiglumis, Elymus goloskokovii, as well as a number of morphologically deviating biotypes, inhabiting Russia and Kazakhstan. Microevolutionary relationships between species were assessed from dendrograms derived from sequences of exons and introns. In all taxa, the St subgenome was represented by St2 variants, rather typical of the North American ancestral line of Pseudoroegneria spicata than of the Asian line descending from Pseudoroegneria strigosa. All putative relatives of E. caninus had H1 subgenome variants linked around the Asian diploid carrier of the H genome from Hordeum jubatum and were divided into two subclades. One of them (H1‐1) contained most of the closely related E. caninus clones, including Elymus uralensis. Another subclade (H1‐2) consisted of five variants phylogenetically related to Elymus mutabilis. We have also studied reproductive relationships between species E. goloskokovii, E. prokudinii, and E. viridiglumis and the degree of their integration into the E. caninus complex. Biotypes included in sexual hybridization formed a single recombination gene pool, within which slight differences in reproductive compatibility were observed. A comprehensive study of microevolutionary differentiation of taxa showed the expediency of taxonomic revision. The species mentioned should probably be relegated to the infraspecific rank within E. caninus s. l.

Using text mining and multilevel association rules to process and analyze incident reports in China

Incident investigation reports provide information on defects related to the system safety and indications for improvements. Currently, the analysis of these reports relies heavily on expert’ experience. The foreseeable work-load and lack of understanding about the importance of near misses have created a situation where severe accidents are rigorously investigated, and minor incidents are often omitted. Consequently, incident reports have not been fully analyzed to provide sufficient solutions.The aim of this research is to propose a framework that uses text mining and multilevel association rules to efficiently structure Chinese incident reports and identify important incident patterns, providing an analysis of trends, rectification strategies, and guidance for safety management.A case study of a construction company in China was conducted using two years of incident data dated 2018–2019, including accidents and near misses. To identify incident elements, a pattern extraction workflow involving TextRank, and domain pertinence was devised based on the linguistic and writing styles of Chinese reports. A concept hierarchy was applied to determine the taxonomic relationships within the risk factors. Multilevel association rule mining was adopted and proven to deliver more comprehensive pattern indications. Comparative and cross-analysis of patterns in different time periods revealed the severity and temporal features of incidents as well as the effectiveness of preventive and precautionary measures. The results also highlight the importance of learning from near miss events. Decision makers can formulate countermeasures and management policies based on these results to improve safety performance.