SEED PROTEIN PROFILES IN THE NARROW-LEAVED SPECIES OF CHENOPODIUM OF THE WESTERN UNITED STATES: TAXONOMIC VALUE AND COMPARISON WITH DISTRIBUTION OF FLAVONOID COMPOUNDS

Water soluble seed proteins from 69 populations representing seven species of Chenopodium were separated electrophoretically. Very little or no intraspecific variation was detected. The use of seed proteins as taxonomic characters was evaluated and compared to data from flavonoid chemistry. Seed proteins are of value in distinguishing C. atrovirens and C. leptophyllum, something which could not be done with flavonoids. Proteins and flavonoid data demonstrated that C. hians and C. leptophyllum are distinct. An analysis of storage proteins failed to differentiate C. desiccatum from C. atrovirens and C. pratericola even though the species are distinct in flavonoids and other characters. Chenopodium atrovirens and C. pratericola produce similar or identical seed proteins, just as they are identical in flavonoids. Seed proteins indicated that plants referable to C. incognitum represent two biological entities, one apparently a minor morphological variant of C. atrovirens and the other conspecific with C. hians. The same interpretation had been given on the basis of flavonoid chemistry. The protein data suggest a close relationship between C. subglabrum on the one hand and C. atrovirens and/or C. desiccatum on the other.     

ALLOZYME VARIATION IN SEVERAL CLOSELY RELATED DIPLOID SPECIES OF CHENOPODIUM OF THE WESTERN UNITED STATES

Twelve allozyme loci were examined in a complex of closely related diploid (2n = 18) members of the genus Chenopodium occurring in the western United States. These plants are generally treated taxonomically as belonging to C. atrovirens, C. desiccatum, C. hians, C. leptophyllum, and C. pratericola. Also included were populations referable to C. incognitum. The enzymes examined and the allelic designations are given as follows: leucine aminopeptidase, Lap; phosphoglucoisomerase, Pgi-1, Pgi-2; glutamate-oxaloacetate transaminase, Got-1, Got-2, Got-3; glutamate dehydrogenase, Gdh; phosphoglucomutase, Pgm-1, Pgm-2; malate dehydrogenase, Mdh-1, Mdh-2; and malic enzyme, Me. All populations were fixed for the same allele at Gdh, Pgi-2, and Mdh-1. Chenopodium hians was fixed for a unique allele at Got-3 and contained two alleles at the Lap locus and two at Pgi-1 which were not detected elsewhere. Chenopodium leptophyllum likewise has unique alleles at Lap and Pgi-1. The other three taxa, C. atrovirens, C. desiccatum and C. pratericola, have alleles at Lap and Pgi-1 which were not found in C. hians or C. leptophyllum. The former three species have the same alleles in highest frequency at all polymorphic loci except Me, where C. desiccatum is consistently separable from C. atrovirens and C. pratericola. Allozyme data are concordant with information from morphology, flavonoid chemistry and seed protein profiles in suggesting that: (1) Chenopodium hians and C. leptophyllum are best regarded as distinct species; (2) C. atrovirens and C. pratericola are very similar and perhaps should not be recognized at the specific level; (3) C. desiccatum appears most closely allied to C. pratericola; (4) plants referable to C. incognitum represent two biological entities, one the same as C. atrovirens, and the other conspecific with C. hians; (5) little genetic variation is detectable in any taxon of these weedy annuals; (6) interspecific hybridization is not a cause of taxonomic difficulties in these plants.     

A numerical study of the common narrow-leaved taxa of chenopodium occurring in the Western United States

A numerical taxonomic study was conducted on the common narrow-leaved members of the genusChenopodium that occur in the western United States. As many as six and as few as two species have been recognized. Thirty-five individual popu lations were used as OTU’s, and 35 characters were considered. The data were subjected to cluster (both the weighted-pair group method and the within-group dispersion method) and principal component analysis. The results of both analyses are in general agreement and suggest phenetic relationships that differ from current interpretations in the literature. It is concluded thatC. desiccatum var.leptophylloides is much more closely related phenetically toC. atrovirens (and may not be distinct from it) than it is toC. desiccatum var.desiccatum. Chenopodium hians andC. leptophyllum appear to be phenetically distinct despite the fact that they have sometimes been viewed as conspecific.Cheno podium subglabrum is not very similar toC. leptophyllum, and should probably be treated as a separate species rather than as a variety of the latter. Popu lations referable toC. incognitum form a rather loose cluster that appears some what intermediate between populations ofC. desiccatum var.leptophylloides,C. atrovirens, C. hians, andC. leptophyllum.     

Phenetic studies in Nuphar Sm. (Nymphaeaceae):variation in sect. Nuphar

Previous taxonomic assessments of the hydrophytic genus Nuphar Sm. (Nymphaeaceae) have inadequately considered the range of morphological variation existing in the genus. A comprehensive statistical analysis of morphological features among the recognized taxa of Nuphar is presented here, first using 10 fruit characters to delimit the separation of two infrageneric groups of taxa, and secondly using 31 characters to quantify the morphological variation found within sect. Nuphar. Results from combined phenetic analyses provided empirical support for recognition of two infrageneric groups of species in the genus (largely by fruit, stigmatic disk margin, neck, and stigmatic disk size) and for separation of taxa within sect. Nuphar (by leaf size, and fruit disk and neck size). Statistical analyses demonstrate that extensive variation in ranges of character states exists among sect. Nuphar taxa. However, a suite of qualitative and quantitative characters can be used to recognize five species and three subspecies within this predominantly Old World assemblage.     

NUMERICAL TAXONOMY OF LIMNANTHACEAE

A numerical taxonomic study of the angiosperm family Limnanthaceae is presented. The 21 OTUs include all taxa recognized in a recent monograph of Limnanthes (Mason, 1952), plus Floerkea proserpinacoides, two undescribed Limnanthes species, and two artificial interspecific F₁ Limnanthes hybrids. One species (L. montana) was treated as two OTUs: measurements for one OTU were taken from field collections and for the other, from garden-grown plants. A maximum of 35 characters was used in the numerical analyses. Raw data for each character were given equal weighting by condensation. Coefficients of resemblance were established using the mean character difference (MCD) method. Tryon's clustering technique (called key communality cluster analysis) was used. Three numerical analyses of Limnanthaceae were made: one with all 35 characters (T analysis), one with 18 floral characters (F analysis), and one with 17 pre- or post-anthesis or vegetative characters (V analysis). Relative positions of OTUs in the T and F analyses are substantially different from those in a conventional taxonomic treatment of the family. The V analysis shows many differences from the T and F analyses. In all analyses the two OTUs representing L. montana were closer to other OTUs than to each other. The two hybrid OTUs showed greater resemblance to one parent than to the other and in two analyses one hybrid was not intermediate between the parents. Similarities between the T and F analyses are explained on the basis of the predominance of floral characters in both. The differences between these two analyses on the one hand and the V analysis and phylogenetic arrangement of the family on the other are attributed to parallelisms in the evolution of floral characters associated with iucreasing autogamy in each of the two phyletic lines in the family. Analyses emphasizing floral characters will place evolutionarily remotely related outcrossing OTUs together and unrelated, autogamous OTUs together. Using characters that are mostly unassociated with the breeding system the positions of OTUs in a numerical analysis are similar to their positions in a phylogenetic arrangement. The V analysis agrees best with suggestions concerning phylogenetic affinities among the taxa in the family, and provides a useful context for the generation of further evolutionary hypotheses.     

Application of FAME (fatty acid methyl ester) analysis in the numerical taxonomic determination of bacterial guild structure

Comparative numerical taxonomic analyses, using fatty acid methyl ester (FAME) profiles and phenetic characteristics, were conducted to examine bacterial guild structure in freshwater sediments. Both approaches were used to examine a subset of 60 OTUs obtained from a previously well characterized microbial community in sediments of a shallow fast flowing stream. For both classifications, greater than 80% of the OTUs were recovered in 11 and 12 major groups for FAME and phenetics approaches. However, there was not complete correspondence for the groupings of the 2 classifications, with most FAME groups being distributed among the phenetic groups and 2 phenetic groups not providing usable characteristics for FAME analysis. The results did demonstrate significant taxonomic variation in bacteria capable of occupying the same or a similar fundamental niche.     

Phenetic and cladistic relationships among tenebrionid beetles (Coleoptera)

Abstract. The higher classification of Tenebrionidae is analysed using numerical phenetic, numerical cladistic and traditional Hennigian methods. In all, eighty characters are examined for about 335 taxa; definitive analyses are made on combinations of eighteen to seventy characters for thirty-three OTUs. At lower levels of relationship (genera and closely related tribes) phenetic and cladistic classifications are shown to be congruent, but at higher levels (tribes and subfamilies) there is marked discordance with phenetic results being more stable. A consensus classification is more similar to the Hennigian cladogram than is any single computer generated cladogram. Two main tribal groups – the Lagrioid and Tenebrionoid groups – are suggested which differ in defensive glands, female anatomy, wing and mouthpart morphology, larval characters and other features. The Tenebrionoid group consists of three main subdivisions – the tenebrionine, coelometopine and diaperine lineages. Changes in classificatory position are recommended for eighty-seven genera and tribes (listed in Appendix E) and implied for numerous others.     

The arctic-alpine polyploids Cerastium alpinum and C. nigrescens (Caryophyllaceae) in a sympatric situation: breakdown of species integrity?

 The high polyploids Cerastium alpinum (8x) and C. nigrescens (12x) were investigated in a mixed population in central Norway to evaluate whether hybridisation has resulted in continuous variation in morphology and genetic markers, a hypothesis previously proposed to account for the extensive taxonomic confusion in this species group. Isozyme, fertility, and morphological (37 characters) variation were examined among 347, 265, and 237 plants, respectively. A PCO analysis based on 23 quantitative morphological characters identified two main groups, corresponding to C. alpinum and C. nigrescens. The groups were also clearly separated in isozyme markers, several qualitative morphological characters, and chromosome numbers. Only 20 plants (8.4%) were more or less intermediate in the PCO analysis. These plants had a parental or hybrid isozyme multilocus phenotype and typically few well-developed anthers, low pollen stainability, and no seed set. Several plants within the C. nigrescens group also had reduced pollen stainability. These results indicate that later-generation hybrids and/or backcrosses towards C. nigrescens are formed. Thus, interspecific, interploidal gene flow probably occurs, but at rates that are insufficient to break down species integrity. Received July 5, 2000 Accepted August 2, 2001     

The influence of spatial scale on the congruence of classifications circumscribing morphological units of biodiversity

Aim The ‘taxonomic impediment’ has led to a growing trend in ecology and conservation biology to use operational surrogates for species within the context of a particular research project. Because such ‘parataxonomic’ classifications are typically spatially limited in scope, we examined the influence of increasing spatial scale on the congruence of two such approaches with a more traditional taxonomic classification. Location Sturt National Park, north‐western New South Wales, Australia. Methods Specimens of two ant genera, Camponotus and Rhytidoponera, were classified by three independent methods. The ‘parataxonomic’ classification assigned specimens to morphospecies without specialist taxonomic expertise; the ‘taxonomic’ classification assigned specimens to either described species or, where this was not possible, to operational taxonomic units (OTUs) using specialist taxonomic expertise; the ‘phenetic’ classification assigned specimens to putative species using a K‐means partitioning algorithm on basic morphometric data. Specimens of each genus were pooled into ‘assemblages’, which were defined at multiple spatial scales using a nested sampling design. Congruence in the interspecimen relationships of the different classifications was tested for each assemblage using pair‐wise Mantel correlations. Results Classification congruence tended to decrease with increasing spatial scale. There were, however, clear differences between the genera. Parataxonomic–taxonomic congruence was consistently greater for Camponotus, while phenetic–taxonomic congruence showed the opposite pattern. Conclusions Observed patterns in classification congruence are attributed to two principal causes: (i) within‐species morphological variation, including ecotypic variation in Rhytidoponera and caste polymorphism in Camponotus; and (ii) a limit to the morphological similarity of potentially competing species at small spatial scales. Regardless of cause, the decline in agreement as the spatial scale of observation is increased has important implications for the measurement of biodiversity, particularly when comparing samples over regional, continental, and global scales.     

Discordance between morphological and molecular species boundaries among Caribbean species of the reef sponge Callyspongia

Sponges are among the most species‐rich and ecologically important taxa on coral reefs, yet documenting their diversity is difficult due to the simplicity and plasticity of their morphological characters. Genetic attempts to identify species are hampered by the slow rate of mitochondrial sequence evolution characteristic of sponges and some other basal metazoans. Here we determine species boundaries of the Caribbean coral reef sponge genus Callyspongia using a multilocus, model‐based approach. Based on sequence data from one mitochondrial (COI), one ribosomal (28S), and two single‐copy nuclear protein‐coding genes, we found evolutionarily distinct lineages were not concordant with current species designations in Callyspongia. While C. fallax, C. tenerrima, and C. plicifera were reciprocally monophyletic, four taxa with different morphologies (C. armigera, C. longissima, C. eschrichtii, and C. vaginalis) formed a monophyletic group and genetic distances among these taxa overlapped distances within them. A model‐based method of species delimitation supported collapsing these four into a single evolutionary lineage. Variation in spicule size among these four taxa was partitioned geographically, not by current species designations, indicating that in Callyspongia, these key taxonomic characters are poor indicators of genetic differentiation. Taken together, our results suggest a complex relationship between morphology and species boundaries in sponges.     

Geometric and traditional morphometrics for the assessment of character state identity: multivariate statistical analyses of character variation in the genus Arrenurus (Acari,Hydrachnidia, Arrenuridae)

Geometric and traditional morphometric approaches are tested to describe and reveal taxonomic characters and character states in variation of shape and size of idiosoma morphology in the Arrenuridae. Patterns of variation of idiosoma and glandularia features of males from 11 Mexican species of Arrenurus (Megaluracarus) and two species of subgenus Dadayella were explored with five landmark configurations and three sets of interlandmark distances. Separate principal component analyses (PCA) and canonical variate analyses (CVA) were performed for each data set. The eight multivariate analyses of variance among 13 a priori groups (species) detected significantly different morphometric variants, which were interpreted as different taxonomic character states. Patterns of character state similarity among species were examined with unweighted‐pair grouping method using averages (UPGMA) cluster analyses on Mahalanobis distances. Analyses of five landmark configurations revealed important taxonomical variation in the anterior idiosoma outline (10 character states), the outline of the posterior region or cauda (13 states), the distribution of postocularia, and the second and third pairs of dorsoglandularia (nine states), the fourth pair of dorsoglandularia (three states), and ventroglandularia on the posterior side of idiosoma (nine character states). Multivariate analyses of three sets of distance measurements also resulted in the detection of potential taxonomic characters related to idiosoma size (12 character states), postocularia and dorsoglandularia (13 states), and ventroglandularia (nine character states). Morphometric analyses of distances and shapes provide a formal basis for the interpretation of taxonomic characters, and for the discovery of character states. These characters should be investigated further in a wider sample of species for the phylogenetic systematics of these water mites. In the meantime, idiosoma regions and structures were tested for congruence in a phylogenetic analysis, and were proposed as homologous among the species sampled.     

Numerical taxonomic studies of the genus Notholca

The genus Notholca has been subjected to taxonomic analysis, using cluster analysis and ordination by principal coordinates analysis, based on 67 phenetic characters. All analyses converge on essentially identical groupings, but fail to inject new hypotheses to remedy the confusing and overlapping taxonomy of the genus. This shortcoming is ascribed to the incompleteness of the character set which currently lacks biochemical and genetic parameters. We suggest to invalidate the subspecies' of N. striata into a single species and consider the pros and cons combining N. haueri and N. latistyla.     

Major lineages within Apiaceae subfamily Apioideae: a comparison of chloroplast restriction site and DNA sequence data

Traditional sources of taxonomic characters in the large and taxonomically complex subfamily Apioideae (Apiaceae) have been confounding and no classification system of the subfamily has been widely accepted. A restriction site analysis of the chloroplast genome from 78 representatives of Apioideae and related groups provided a data matrix of 990 variable characters (750 of which were potentially parsimony-informative). A comparison of these data to that of three recent DNA sequencing studies of Apioideae (based on ITS, rpoCl intron, and matK sequences) shows that the restriction site analysis provides 2.6–3.6 times more variable characters for a comparable group of taxa. Moreover, levels of divergence appear to be well suited to studies at the subfamilial and tribal levels of Apiaceae. Cladistic and phenetic analyses of the restriction site data yielded trees that are visually congruent to those derived from the other recent molecular studies. On the basis of these comparisons, six lineages and one paraphyletic grade are provisionally recognized as informal groups. These groups can serve as the starting point for future, more intensive studies of the subfamily.     

A REANALYSIS OF NEST STRUCTURE IN THE WEAVERS (PLOCEINAE) USING NUMERICAL TAXONOMIC TECHNIQUES

Variables of nest architecture and construction behaviour of 62 species of ploceine finches studied by Crook (1963) were reanalysed using multivariate statistical techniques. Phenetic assessments were based on 38 two-state characters for 48 OTUs. Product moment correlation coefficients and average distance coefficients were used as measures of similarity, and species were clustered using the unweighted pair-group method with arithmetic averages. A three-dimensional model was constructed of species plotted with respect to the first three principal components extracted from a matrix of correlations among characters. Principal component and factor analytic techniques were employed to determine trends in character variation. The phenetic affinities expressed in the 3-D model and two phenograms show many similarities to the phenetic groupings deduced by Crook. However, there were also some differences in interpretation. Crook's Modes C and D were shown as distinct clusters in my analyses, but Modes A and B did not separate completely. In particular, the globular nest of P. baglafecht of Mode A, Type IV, grouped with kidney-shaped nests of species of Mode B, Type Va. The treatment of P. pelzelni, P. madagascariensis, and P. philippinus in my analysis differed somewhat from Crook's. The resulting cluster of F. sechellarum and M. malimbicus brought out some effects of standardising data on resulting interpretations of similarity. Species within the subtypes of Crook usually remained close together, but the affinities between subtypes (and types) often differed between our studies. The results of factor and principal component analyses indicate that the main trends in character variation concern those traits found together in (a) M. rubriceps; (b) A. unicolor and Pa. superciliosus; (c) forest birds; and (d) non-forest birds. These groups also are the main clusters. Differences in Crook's and my results are discussed and some of the advantages of utilising numerical techniques to describe similarity are mentioned.     

Phenetic relationships inClerodendrum (Verbenaceae) and some phylogenetic considerations

Cluster analyses by different methods and a minimum spanning tree were used to study phenetic relationships in the genusChlerodendrum. 129 species were scored for 52 morphological characters corresponding to 119 character states. The phenetic results suggest a classification into 7 distinct groups, which may be grouped into two subgenera. This classification is supported by the iridoid distribution as well as by some phylogenetic considerations.     

THE QUANTIFICATION OF SOME PLANT-TAXA CIRCUMSCRIPTIONS

Intrataxon variability is estimated by the technique of numerical taxonomy. Taxa which had been determined by orthodox taxonomic methods are subjected to analyses by numerical phenetics. Comparisons are made of the amounts of cohesion among the members of different taxa in the Bromeliaceae at several taxonomic levels by computing the degrees of similarities between members of the same taxon and of different taxa. Results of these comparisons with several taxa reveal that the variability of a taxon in terms of phenetic distance computed with a large number of characters does not necessarily agree with a subjective appraisal of variability. The method facilitated difficult taxonomic determinations and provided an estimate of the relative evolutionary ages of different taxonomic groups.     

Cryptic diversity,intraspecific phenetic plasticity and recent geographical translocations in Branchiomma (Sabellidae,Annelida)

The importance of identifying biological diversity accurately and efficiently is becoming more evident. It is therefore critical to determine the species boundaries between closely related taxa and to establish diagnostic characters that allow us to define species. This is not an easy task when species exhibit high intraspecific phenotypic plasticity or when distinct evolutionary lineages with an unusually large amount of genetic distinctiveness show no apparent morphological diversity (cryptic species). These phenomena appear to be common in the genus of fan worms Branchiomma (Sabellidae, Annelida), and consequently, taxonomic errors are widespread in the group. Moreover, some Branchiomma species have been unintentionally translocated outside the area where natural range extension is expected, increasing the taxonomic problems. We have performed a range of analytical methods including genetic distances, Bayesian inference, maximum likelihood, maximum parsimony, statistical parsimony analyses and general mixed Yule coalescent model to clarify the taxonomic status and assess the species boundaries of Branchiomma in Australia. This study shows that the traditional diagnostic morphological features are greatly homoplastic. Results also indicate that the diversity of Branchiomma in Australia is higher than previously reported and evidence some cases of high phenetic plasticity (in features previously considered as stable within species), high intraspecific genetic variability, cryptic species and several unexpected cases of translocations.     

A multivariate analysis of geographic variation in morphology inPersoonia mollis (Proteaceae)

This study highlights the utility and limitations of multivariate procedures for the analysis and taxonomic interpretation of geographic variation within a complex species. Morphological data from herbarium specimens ofPersoonia mollis (Proteceae) were analyzed by two ordination procedures, multidimensional scaling (MDS) and canonical variate analysis (CVA). Support for the earlier recognition of nine infraspecific taxa was found. However, plots of canonical variate scores against latitute or longitude across parapatric subspecies boundaries revealed unexpected phenetic homogeneity within subspecies with sharp transitions between subspecies. The geographic variation in morphology withinP. mollis can be best described as a mosaic of nine recognisably distinct and internally homogeneous allopatric or parapatric taxa, where neighbouring taxa share surprisingly narrow zones of morphological transition at ecotones. The utility of these procedures was highlighted by the recovery of unexpected patterns of variation. However, questions of rank remain unresolved by phenetic analysis alone.     

Taxonomic significance of biométric characters and the consequences for classification and biostratigraphy, exemplified through moussoneliform daonellas (Daonella, Bivalvia; Triassic)

The middle Triassic bivalve genusDaonella Mojsisovics, 1874 would be an ideal guide fossil (worldwide distribution, high evolutionary rates); however, the classification of daonellas is difficult. Most daonellas lack distinct characters and have a wide range of morphologic variation. A new taxonomic attempt was necessary to get a coherentDaonella classification. The new taxonomic concept proposed herein consists of four steps. (1) Biometric characters are defined unambiguously, based on landmarks and pseudolandmarks. (2) The taxonomic significance of biometric characters is analyzed. Several characters depend significantly on growth stage of specimens or on the lithology of fossil localities. In addition, the intercorrelations between biometric characters are studied to exclude weighting in some morphologic features. The study of the taxonomic significance of biometric characters shows, how important a careful selection of taxonomic characters is. (3) Most daonellas are not determinable by univariate or bivariate methods. The principle component analysis (PCA) is applied to detect groups of similar holomorphs in multivariate space. (4) The interpreted groups from PCA are applied to a canonical discriminant function analysis. This analysis helps in deciding whether two groups are sufficiently distinct to be separated as different species. This new taxonomic concept was applied to moussoneliform daonellas of the middle Triassic from the Southern Alps. Three different forms were used for the study herein:Daonella moussoni (Mérian, 1853) from the Varenna Limestone (Perledo-Varenna Formation, Grigna, Italy),D. aff.moussoni (Mérian)Rieber, 1969 from the lower Meride Limestone (Monte San Giorgio, Switzerland) andD. pseudomoussoni Rieber, 1969 from the Grenzbitumenzone (Monte San Giorgio, Switzerland). The new classification shows thatD. pseudomoussoni is a separate species and distinguishable fromD. moussoni andD. aff.moussoni, which belong to the same species. A coherent systematics ofDaonella becomes possible on the basis of newly defined taxonomic characters. Daonellas can now be used as relevant guide fossils for the middle Triassic. The presented example demonstrates a biostratigraphic correlation between the lower Meride Limestone at Monte San Giorgio and the Varenna Limestone at Grigna. The stratigraphic distribution ofD. moussoni can be assigned to thegredleri Zone.     

Metabarcoding of freshwater invertebrates to detect the effects of a pesticide spill

Biomonitoring underpins the environmental assessment of freshwater ecosystems and guides management and conservation. Current methodology for surveys of (macro)invertebrates uses coarse taxonomic identification where species‐level resolution is difficult to obtain. Next‐generation sequencing of entire assemblages (metabarcoding) provides a new approach for species detection, but requires further validation. We used metabarcoding of invertebrate assemblages with two fragments of the cox1 “barcode” and partial nuclear ribosomal (SSU) genes, to assess the effects of a pesticide spill in the River Kennet (southern England). Operational taxonomic unit (OTU) recovery was tested under 72 parameters (read denoising, filtering, pair merging and clustering). Similar taxonomic profiles were obtained under a broad range of parameters. The SSU marker recovered Platyhelminthes and Nematoda, missed by cox1, while Rotifera were only amplified with cox1. A reference set was created from all available barcode entries for Arthropoda in the BOLD database and clustered into OTUs. The River Kennet metabarcoding produced matches to 207 of these reference OTUs, five times the number of species recognized with morphological monitoring. The increase was due to the following: greater taxonomic resolution (e.g., splitting a single morphotaxon “Chironomidae” into 55 named OTUs); splitting of Linnaean binomials into multiple molecular OTUs; and the use of a filtration‐flotation protocol for extraction of minute specimens (meiofauna). Community analyses revealed strong differences between “impacted” vs. “control” samples, detectable with each gene marker, for each major taxonomic group, and for meio‐ and macrofaunal samples separately. Thus, highly resolved taxonomic data can be extracted at a fraction of the time and cost of traditional nonmolecular methods, opening new avenues for freshwater invertebrate biodiversity monitoring and molecular ecology.