scholarly journals Multivariate ratio analysis and DNA markers reveal a new Australian species and three synonymies in eucalypt-gall-associated Megastigmus (Hymenoptera: Megastigmidae)

2020 ◽  
Vol 110 (6) ◽  
pp. 709-724 ◽  
Author(s):  
Ngoc Hoan Le ◽  
Helen F. Nahrung ◽  
Jess A. T. Morgan ◽  
Simon A. Lawson
Keyword(s):  
Species Delimitation ◽  
Size Variation ◽  
First Record ◽  
Morphological Characters ◽  
Molecular Data ◽  
Species Discrimination ◽  
Ratio Analysis ◽  
Body Parts ◽  
Diagnostic Characters ◽  
Taxonomic Decision

AbstractThe genus Megastigmus Dalman, 1820 (Hymenoptera: Megastigmidae) contains potential biocontrol agents of the invasive eucalypt galling chalcid Leptocybe spp. (Hymenoptera: Eulophidae), with several species reported in various parts of the world. Species discrimination is challenging due to intraspecific morphological variation, difficulty in measuring sizes of body parts, and the lack of information regarding the global distribution of parasitic Megastigmus. We used two species commonly associated with Leptocybe in its native range to review taxonomic methods and determine the most reliable morphological characters in species delimitation. We examined size variation of body characters, and conducted species discrimination using multivariate ratio analysis, mitochondrial Cytochrome c oxidase subunit 1 (COI) and nuclear 28S rDNA (28S) sequences. Morphological traits were effective in species delimitation yet revealed high variation in several characters employed in current keys. Knowledge generated on morphology and DNA justified the description of a new species, M. manonae, sp. n., the first record of M. pretorianensis in Australia, and revised diagnostic characters for M. zvimendeli. Based on these diagnostic characters and molecular data, we synonymize three species (M. judikingae, syn. n., from Australia, M. sichuanensis, syn. n., from China and M. icipeensis, syn. n., from Kenya) with M. zvimendeli. Our findings highlight the importance of molecular markers in assisting taxonomic decision-making and the need for coordinated work in identifying Megastigmus associated with Leptocybe spp.

Intraspecific variability of morphological characters in the species-rich deep-sea genus Acantholaimus Allgén, 1933 (Nematoda: Chromadoridae)

Nematology ◽  
2016 ◽  
Vol 18 (4) ◽  
pp. 455-473 ◽  
Author(s):  
Dmitry M. Miljutin ◽  
Maria A. Miljutina
Keyword(s):  
Deep Sea ◽  
Intraspecific Variability ◽  
Morphological Characters ◽  
Molecular Data ◽  
Species Discrimination ◽  
Species Differentiation ◽  
Lateral Field ◽  
Operational Taxonomic Units ◽  
General Arrangement ◽  
Taxonomic Approach

Acantholaimusis a species-rich genus of deep-sea nematodes, often with dozens of species found at the same locality but each represented by single or few individuals. Species discrimination by morphological characters in this genus is therefore often difficult due to transitional forms that may be referred to several species because of lack of data on intraspecific variability. The aim of this study was to evaluate the intraspecific variability of morphological characters that are most often used inAcantholaimustaxonomy, in order to distinguish those which are most informative for species differentiation. A reverse taxonomic approach was applied for initial species discrimination. Two loci, one each from small and large subunits of rRNA, were sequenced for 59Acantholaimusspecimens from two deep-sea locations. Twenty-seven Molecular Operational Taxonomic Units (MOTU) were identified, of which 12 were represented by more than one individual. These were then analysed for intraspecific variability in morphological characters. Some of the examined characters showed high intraspecific variability; specifically: length of cephalic setae; distance from anterior end to amphid; shape of anterior setae; position and arrangement of cervical setae. In the absence of genetic data, these characters should be used with caution for differential diagnoses or species discrimination. Other characters were more conservative within the same MOTU: body proportions; length of outer labial setae; amphidial diam.; appearance of lateral field; general arrangement of cervical setae; and shape of tail. These characters may be successfully used for species discrimination in the absence of molecular data.

Species delimitation of colour polymorphic Cladophorus (Coleoptera: Lycidae) from New Guinea

Zootaxa ◽  
2017 ◽  
Vol 4320 (3) ◽  
pp. 505 ◽  
Author(s):  
ROMANA KALOUSOVA ◽  
LADISLAV BOCAK
Keyword(s):  
Phylogenetic Analysis ◽  
Mitochondrial Dna ◽  
Related Species ◽  
Species Delimitation ◽  
Morphological Differentiation ◽  
Morphological Characters ◽  
Molecular Data ◽  
Closely Related Species ◽  
Dna Fragment ◽  
Colour Patterns

Cladophorus Guérin-Méneville, 1830 are endemic Papuan net-winged beetles which take part in highly diverse Müllerian mimicry rings. Available specimens were sequenced for cox1–tRNA-Leu–cox2 mitochondrial DNA fragment and the species delimitations were based on the genetic distance, phylogenetic analysis, and morphology. Three earlier described species were identified in the recently collected material and further 10 species are described: C. pallescens sp. nov., C. bicolor sp. nov., C. craterensis sp. nov., C. motykai sp. nov., C. mindikensis sp. nov., C. kailakiensis sp. nov., C. manokwarensis sp. nov., C. haiaensis sp. nov., C. humeralis sp. nov., and C. boceki sp. nov. DNA-based identifications provided some ambiguous results and closely related species could not be robustly delimited using solely molecular data. Additionally, the species limits were based on clearly defined morphological characters and the morphological differentiation was found unlinked from the genetic divergence. Colour patterns cannot be used for identification because all species available in more specimens were polymorphic and followed various local co-mimics. The Papuan fauna of Cladophorus is very diverse and the closely related species regularly occur in limited regions. Differentiation within restricted ranges is therefore considered as the main speciation mode. 

scholarly journals DNA Barcoding: Mixed results for big-headed flies (Diptera: Pipunculidae)

Zootaxa ◽  
2007 ◽  
Vol 1423 (1) ◽  
pp. 1-26 ◽  
Author(s):  
JEFFREY H. SKEVINGTON ◽  
CHRISTIAN KEHLMAIER ◽  
GUNILLA STÅHLS
Keyword(s):  
Dna Barcoding ◽  
Sequence Data ◽  
Phylogenetic Signal ◽  
Morphological Characters ◽  
Molecular Data ◽  
Morphological Data ◽  
Base Pairs ◽  
Data Set ◽  
Taxonomic Decision ◽  
Morphological Species

Sequence data from 658 base pairs of mitochondrial cytochrome c oxidase I (cox1) were analysed for 28 described species of Pipunculidae (Diptera) in an effort to test the concept of DNA Barcoding on this family. Two recently revised but distantly related pipunculid lineages with presumed different evolutionary histories were used for the test (Clistoabdominalis Skevington, 2001 and Nephrocerus Zetterstedt, 1838). An effort was made to test the concept using sister taxa and morphologically similar sibling species swarms in these two genera. Morphological species concepts for Clistoabdominalis taxa were either supported by cox1 data or found to be too broad. Most of the discordance could be accounted for after reassessing morphological characters. In these cases, the molecular data were invaluable in assisting taxonomic decision-making. The radiation of Nearctic species of Nephrocerus could not be diagnosed using cox1. The ability of cox1 to recover phylogenetic signal was also tested on Clistoabdominalis. Morphological data for Clistoabdominalis were combined with the molecular data set. The pipunculid phylogeny from molecular data closely resembles the published phylogeny based on morphology. Partitioned Bremer support is used to localize areas of conflict between the datasets.

A new species of the genus Lucasioides Kwon, 1993 (Isopoda, Oniscidea, Agnaridae) from Siberia, Russia

Zootaxa ◽  
2021 ◽  
Vol 4903 (1) ◽  
pp. 140-150
Author(s):  
KONSTANTIN B. GONGALSKY ◽  
PAVEL S. NEFEDIEV ◽  
ILYA S. TURBANOV
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
First Record ◽  
Morphological Characters ◽  
Molecular Data ◽  
Altai Mountains ◽  
The Family ◽  
Southwestern Siberia ◽  
A New Species ◽  
Preliminary Phylogenetic Analysis

A new species of the family Agnaridae, Lucasioides altaicus sp. nov., is described from the Altai Mountains, southwestern Siberia, based both on morphological characters and molecular data. This species is the first record of Lucasioides from Russia, whose location is the northernmost habitat of terrestrial isopods in indigenous habitats presently known to Eurasia. The diagnostic characters of the new species and a preliminary phylogenetic analysis within Agnaridae are provided. 

scholarly journals Which morphological characters are influential in a Bayesian phylogenetic analysis? Examples from the earliest osteichthyans

2019 ◽  
Vol 15 (7) ◽  
pp. 20190288 ◽  
Author(s):  
Benedict King
Keyword(s):  
Bayesian Analysis ◽  
Tooth Enamel ◽  
Simple Procedure ◽  
Phylogenetic Analyses ◽  
Morphological Characters ◽  
Molecular Data ◽  
Body Parts ◽  
Bayesian Phylogenetic Analysis ◽  
Recent Debate ◽  
Phylogenetic Hypotheses

There has been much recent debate about which method is best for reconstructing the tree of life from morphological datasets. However, little attention has been paid to which characters, if any, are responsible for topological differences between trees recovered from competing methods on empirical datasets. Indeed, a simple procedure for finding characters supporting conflicting tree topologies is available in a parsimony framework, but an equivalent procedure in a model-based framework is lacking. Here, I introduce such a procedure and apply it to the problem of the ‘psarolepid’ osteichthyans. The ‘psarolepids’, which include the earliest known osteichthyans, are weakly supported as stem osteichthyans under parsimony but strongly supported as sarcopterygians in Bayesian analysis. The Bayesian result is driven by just two characters, both of which relate to the intracranial joint of sarcopterygians. Important characters that support a stem osteichthyan affinity for ‘psarolepids’, such as the absence of tooth enamel, have virtually no effect in a Bayesian framework. This is because of a bias towards characters with relatively complete sampling, a bias that has previously been reported for molecular data. This has important implications for Bayesian analysis of morphological datasets in general, as characters from different body parts commonly have different levels of coding completeness. Methods to critically appraise character support for conflicting phylogenetic hypotheses, such as that used here, should form an important part of phylogenetic analyses.

Species delimitation of the praying mantis Hierodula patellifera (Audinet-Serville) based on morphological and molecular characters (Mantodea: Mantidae)

Zootaxa ◽  
2021 ◽  
Vol 4951 (1) ◽  
pp. 147-158
Author(s):  
JAEIL SHIM ◽  
HAECHUL PARK ◽  
SEONGHYUN KIM ◽  
HO-JONG JU ◽  
JEONG-HUN SONG
Keyword(s):  
Species Delimitation ◽  
Male Genitalia ◽  
Gene Tree ◽  
Distinct Species ◽  
Morphological Characters ◽  
Molecular Data ◽  
Neighbor Joining ◽  
Praying Mantis ◽  
Taxonomic Analysis ◽  
Molecular Characters

An integrative taxonomic analysis of Hierodula patellifera (Audinet-Serville) is presented based on morphological and molecular characters (COI, 28S rDNA). During repeated trips to the Korean peninsula, we collected unusual specimens from Wanju-gun. They were similar to H. patellifera, but can be distinguished by a larger body size, the number and shape of spines on foreleg, and the shape of male genitalia. To examine the phenotypes and delimit H. patellifera from fourteen sampled populations, we used forecoxal spines and male genitalia as key morphological characters, as well as molecular data including gene tree monophyly and genetic divergence data. The molecular analyses (p-distance, neighbor-joining, and parsimony analyses) did not separate the specimens as two distinct species. The diagnostic characters of H. patellifera are illustrated with habitus images. 

scholarly journals First Report of Crown Rot Caused by Cylindrocladium pauciramosum on Scarlet Honey Myrtle in Italy

Plant Disease ◽  
2009 ◽  
Vol 93 (11) ◽  
pp. 1217-1217 ◽  
Author(s):  
G. Polizzi ◽  
D. Aiello ◽  
I. Castello ◽  
G. Parlavecchio ◽  
A. Vitale ◽  
...  
Keyword(s):  
Plant Root ◽  
Intergenic Spacer ◽  
Soil Surface ◽  
First Record ◽  
Morphological Characters ◽  
Molecular Data ◽  
Crown Rot ◽  
Centraalbureau Voor ◽  
Potted Plants ◽  
Plant Pathol

Scarlet honey myrtle (Melaleuca fulgens R. Br.), native to Australia, is an evergreen colorful shrub (Myrtaceae) and grown in Italy as an ornamental plant. During November 2008, a widespread disease was noticed on ~90% of 3,000 6-month-old M. fulgens cv. Red potted plants. Plants were obtained from cuttings and produced by a commercial nursery in Catania Province. Symptomatic plants showed a crown rot and longitudinal sections of tissues revealed a brown discoloration of the basal stem. As a consequence, leaves gradually became necrotic and abscised, followed by death of the entire plant. Root rots and leaf spots were not observed. M. gibbosa, M. ericifolia, M. thymifolia, and M. elliptica, cultivated in the same nursery, did not show disease symptoms. A Cylindrocladium sp. was consistently isolated from the crown and basal stem of symptomatic plants on potato dextrose agar (1). Ten Cylindrocladium isolates obtained from infected basal stems and crowns were selected and cultured for 8 days at 25°C on carnation leaf agar (CLA). Macroconidiophores consisted of a stipe, a penicillate arrangement, and a stipe extension terminating in an obpyriform to ellipsoidal vesicle (6 to 10 μm in diameter). Cylindrical conidia were rounded at both ends, straight, 1-septate, and 42 to 60 × 4 to 5 μm. All single-conidial isolates were mated with opposite tester strains of C. pauciramosum on CLA and produced fertile perithecia (3). Perithecia were solitary or in groups, orange to red-brown, subglobose to ovoid, and 270 to 400 μm high × 180 to 290 μm in diameter. Further confirmation of species was obtained by amplification and sequencing of the intergenic spacer (IGS) region of rDNA with the M13 forward (-20) and M13 reverse primers. On the basis of the complete IGS sequence, two primer sets (218F/218R and 106F/106R) were designed and successfully used in a nested-PCR protocol for the detection of C. pauciramosum from tissues of infected plants (2). On the basis of morphological characters, mating type, and molecular data, the isolates were identified as C. pauciramosum C.L. Schoch & Crous. One representative isolate (DISTEF-MFR2; CBS 124657) was deposited at Centraalbureau voor Schimmelcultures open fungi collection (Fungal Biodiversity Centre, Utrecht, the Netherlands). Pathogenicity tests were performed by adding sterile water to CLA cultures of C. pauciramosum from a single-conidial isolate and incorporating the resulting spore suspension (105 conidia per ml) on the soil surface of 20 3-month-old M. fulgens cv. Red potted plants. The same number of plants served as uninoculated controls. Following inoculation, plants were well irrigated and maintained in a growth chamber at 25 ± 1°C and 90 to 95% relative humidity. All inoculated plants developed crown rot symptoms identical to those observed in the nursery 2 months after inoculation. Control plants remained symptomless. C. pauciramosum was always reisolated from the infected plants and identified as previously described. C. pauciramosum was previously detected in Italy as being responsible for a leaf spot on M. hypericifolia (3). To our knowledge, this is the first record in the world of crown rot of scarlet honey myrtle caused by C. pauciramosum. References: (1) P. W. Crous. Taxonomy and Pathology of Cylindrocladium (Calonectria) and Allied Genera. The American Phytopathological Society, St. Paul MN, 2002. (2) F. Nigro et al. J. Plant Pathol. 88:S22, 2006. (3) G. Polizzi and P. W. Crous. Eur. J. Plant Pathol. 105:407, 1999.

Semenovia torilifolia is conspecific with S. malcolmii (Apiaceae) based on morphology and molecular data

Phytotaxa ◽  
2017 ◽  
Vol 321 (3) ◽  
pp. 225 ◽  
Author(s):  
QUN-YING XIAO ◽  
HAO-YU HU ◽  
FEN TONG ◽  
MIN-JIE LI ◽  
XING-JIN HE
Keyword(s):  
Tibetan Plateau ◽  
Morphological Traits ◽  
Phylogenetic Analyses ◽  
Morphological Characters ◽  
Molecular Data ◽  
Diagnostic Characters ◽  
Field Investigations ◽  
Literature Reviews ◽  
Nuclear Its ◽  
The Relationship

Semenovia torilifolia and S. malcolmii have been recorded to co-occur in Qinghai-Tibetan Plateau and adjacent regions. However, there were no available diagnostic characters to distinguish them. In the present study, we reconstructed the phylogeny based on nuclear ITS and ETS regions, and explored valid morphological traits through extensive fieldwork, specimen examinations and literature reviews, to determine the relationship between S. torilifolia and S. malcolmii. Our field investigations found that the morphological characters between S. torilifolia and S. malcolmii are continuous. Phylogenetic analyses revealed that S. torilifolia and S. malcolmii are nested together and formed a well-supported monophyletic taxa (90% BS, 1.00 PP) within Semenovia clade. It is thus sweeping concluded that S. torilifolia is conspecific with S. malcolmii.

A new species of the genus Kodaianellissus Wang, Bourgoin & Zhang (Hemiptera: Issidae) with morphological and molecular data

Zootaxa ◽  
2020 ◽  
Vol 4731 (2) ◽  
pp. 270-274
Author(s):  
KAMRAN SOHAIL ◽  
WEIJIAN HUANG ◽  
YALIN ZHANG
Keyword(s):  
New Species ◽  
Molecular Analysis ◽  
Male Genitalia ◽  
First Record ◽  
Morphological Characters ◽  
Molecular Data ◽  
Morphological And Molecular Data ◽  
A New Species

Kodaianellissus gibbusis sp. nov. is described from Rawlakot, Azad Jammu & Kashmir (Pakistan), which is first record of the genus Kodaianellissus Wang, Bourgoin & Zhang, 2017 from the country. Morphological characters including male genitalia structure are described and illustrated. A checklist and key to all species of Kodaianellissus are provided. A molecular analysis with morphological characters indicates its placement into the Kodaianellissus. 

scholarly journals A molecular phylogenetic approach to the New Zealand species of Enantiobuninae (Opiliones : Eupnoi : Neopilionidae)

2014 ◽  
Vol 28 (6) ◽  
pp. 565 ◽  
Author(s):  
Sebastián Vélez ◽  
Rosa Fernández ◽  
Gonzalo Giribet
Keyword(s):  
New Zealand ◽  
Sexual Dimorphism ◽  
Morphological Characters ◽  
Molecular Data ◽  
Soil Arthropods ◽  
Diagnostic Validity ◽  
Diagnostic Characters ◽  
Molecular Phylogenetic ◽  
Taxonomic Implications ◽  
Historical Issues

Members of the New Zealand Enantiobuninae constitute some of the most charismatic soil arthropods of the archipelago, and a striking example of sexual dimorphism, with nondescript females but colourful males boasting exaggerated chelicerae many times longer than their bodies. The genera Forsteropsalis and Pantopsalis recently underwent revision, but many questions remained about the validity of species designations owing to historical issues of characters of dubious taxonomic value, female specimens designated as holotypes despite the males holding all the diagnostic characters, and the suspected presence of more than one male form within some species. We present the first phylogeny based on molecular data for the New Zealand species in the genera Forsteropsalis, Pantopsalis and Mangatangi, and comment on the taxonomic implications of our results, including the diagnostic viability of important morphological characters. Our analyses reject the monophyly of Neopilionidae and Forsteropsalis, but support the monophyly of Pantopsalis. Finally, we comment on the taxonomic implications of the results, including the diagnostic validity of morphological characters traditionally used on the groups.

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