The larva of the genus Tolmerinus Bernhauer described: does it help to reveal a sister-group for the rove beetle subtribe Anisolinina (Coleoptera: Staphylinidae: Staphylininae)?

Szalay, F. S. (Department of Anthropology, Hunter College, City University of New York, 695 Park Avenue, New York, New York 10021; Department of Vertebrate Paleontology, American Museum of Natural History, New York, New York 10024) 1977. Ancestors, descendants, sister groups and the testing of phylogenetic hypotheses. Syst. Zool. 26:12-18. -It is argued that the practice of expressing all phylogenetic relationships as cladistic relationships (i.e. splittings, those expressed only in the form of dichotomous sister group relationships) gives an incomplete and therefore potentially misleading view of evolutionary history. Consequently such schemes tend to supply hypotheses that fail to mirror evolutionary descent. Application of shared derived characters to set up phylogenetic hypotheses is a mere consequence of establishing morphocline polarities. Therefore, the of a phylogenetic hypothesis lies in the soundness of biological (developmental, functional, etc.) investigations of character clines. challenging issue then is the testability of morphocline polarity hypotheses, rather than competing phylogenetic schemes. Age of any phenon is one of its attributes, its fourth dimension. In addition to those same considerations as are employed in dealing with sister group hypotheses (shared-derived characters), ancestordescendant hypotheses may also be tested by the temporal position of the taxon. According to the Popperian view of criteria, postulated ancestor-descendant relationships may be falsified by biostratigraphic evidence, and therefore such hypotheses are as scientific as those of a sister-group nature. Phylogenetic trees are preferred over cladograms because the former always contain more information since they can express both ancestor-descendant relationships (anagenesis) as well as sister group relationships (cladogenesis). A brief synopsis is offered for the procedure to establish historical relationships of taxa. [Phylogeny reconstruction; morphocline polarity hypotheses; ancestor-descendant relationships.] The relative age of different characters should in all cases be a prime object of research. This historical method (although open to many pitfalls) when judiciously applied seems more likely to lead to lasting phylogenetic results than the time-honored method of setting down all the resemblances and differences between two animals, without furtlher analysis, and then striking a balance at the end. The greatest stumbling blocks of the phylogenist lie: first in the difficulty of distinguishing between primitive and specialized characters, secondly in the tendency to assume relationship between two given forms on the basis of resemblances that may have been brought about by either parallel or convergent evolution. W. K. Gregory (1910) A genealogy or phylogeny involves both sister-group and ancester-descendant relationships. Increasingly, however, in what has become known as cladistic analysis, expression of all hypothesized phylogenetic relationships has become restricted to sister-group relationships even in instances when the fossil record is excellent (see for example, Eldredge and Tattersall, 1975). As evolution embraces the phenomenon of splitting as well as ancestor-descendant relationships, it is useful to briefly examine the exclusive practice of employing the concept of dichotomies without ancestordescendant relationships, the use of cladograms, and various claims as towhat really constitutes the test of a phylogenetic hypothesis. SISTER GROUPS AND ANCESTOR-DESCENDANT

We have taken a total-evidence approach to the phylogeny of 29 extant echinoids, combining data from larval morphology, adult morphology, small subunit rRNA complete gene sequence and large subunit rRNA partial gene sequence: a total of 176 morphological and 121 molecular phylogenetically informative characters. Also included are 13 extinct taxa for which we know only adult morphology. Parsimony analysis of the combined data generated 28 equally parsimonious solutions, differing primarily in the positioning of a few fossil taxa. We reduced these to a single working hypothesis of echinoid relationships by pruning fossil taxa and one extant species. Patterns of morphological evolution of larval and adult stages were compared by optimizing character sets onto the total evidence tree and assigning each character transformation to a branch. Branch nodes were dated by reference to the first appearance of one or other sister taxon in the fossil record. From this we demonstrate that larval and adult morphological evolution has proceeded in a mosaic-like fashion over the last 250 Ma. A similar comparison between morphological and molecular data finds equally weak correlation between rates of ribosomal RNA evolution and rates of morphological evolution, implying that morphology and ribosomal genes have also evolved largely independently. Larval characters appear to be more prone to homoplasy than adult characters, even when comparison is restricted to adult organs of similar size and structural complexity as the larvae. As morphological and molecular apomorphies accrue over time, there is a general correspondence between the duration of a particular branch and the number of apomorphies assigned to that branch. However, we found no evidence that overall molecular rates of evolution were any more strictly clock-like than morphological character transformations, although mapping transversions only improved the fit to a clock-like model for molecular data.

Evidence is presented in support of the following phylogenetic hypotheses: (1) Sipuncula are the sister taxon of Mollusca; (2) the two aplacophoran taxa, Neomeniomorpha (= neomenioids) and Chaetodermomorpha (= chaetoderms), are monophyletic with a common neomenioid-like ancestor, and of the two taxa, Chaetodermomorpha are more derived; (3) Aplacophora and Polyplacophora are sister taxa and form a clade, Aculifera; (4) Aculifera are the sister group of the remaining extant mollusks, Conchifera; and (5) Aplacophora are progenetic Aculifera. The evidence is based on homologies of early and late embryological development, adult morphologies, and molecular analyses. Embryological development in sipunculans and mollusks shows a close relationship between them, and embryological development of the shell separates Aculifera and Conchifera. Adult morphologies indicate: (1) monophyly of Aplacophora; (2) sister-group relationship between Aplacophora and Polyplacophora; (3) a molluscan plesiomorphy of nonsegmented serial replication of organs; and (4) progenesis in Aplacophora. Molecular evidence supports the embryological and morphological relationships between Sipuncula and Mollusca. Mollusca are thus hypothesized to be coelomate Eutrochozoa, which share an ancestor that probably had serial replication of organs. Differences in size and structure of the coelom among Eutrochozoa are hypothesized to have been brought about by changes in the timing and the process of cavitation of the mesodermal bands that arise from cell 4d. Through the process of progenesis Aplacophora retained an ovoid embryological shape and several internal structures that, although they appear to be in a primitive state, are actually secondarily derived as is quadrant D specification during early cleavage.

The genus Antimerus Fauvel, 1878, endemic to eastern Australia and Tasmania and a phylogenetically enigmatic member of the large rove beetle tribe Staphylinini, is revised. The genus and each of its four previously known species are redescribed, and a lectotype is designated for Antimerus punctipennis Lea, 1906. Five species are described as new: Antimerus metallicus sp. n., Antimerus jamesrodmani sp. n., Antimerus gracilis sp. n., Antimerus bellus sp. n. and Antimerus monteithi sp. n., so that the number of known species in this genus now totals nine. For the first time Antimerus larvae are described, tentatively identified as Antimerus smaragdinus Fauvel, 1878, Antimerus punctipennis and Antimerus metallicus. Available distributional and bionomic data are provided for each species and summarized in the discussion. Adult and larval morphology of Antimerus and its distribution patterns are discussed in the broader context of new data on the evolution of the entire tribe Staphylinini, and with respect to the formation of the Australian fauna of this tribe. The phylogenetic position of Antimerus within Staphylinini remains unresolved pending a targeted formal study. However, a majority of currently available data suggests that it could be a basal member of the recently recovered monophyletic clade of Staphylinini tentatively called “Staphylinini propria”.

Abstract.This is the most comprehensive analysis of higher‐level relationships in Odonata conducted thus far. The analysis was based on a detailed study of the skeletal morphology and wing venation of adults, complemented with a few larval characters, resulting in 122 phylogenetically informative characters. Eighty‐five genera from forty‐five currently recognized families and subfamilies were examined. In most cases, several species were chosen to serve as exemplars for a given genus. The seven fossil outgroup taxa included were exemplar genera from five successively more distant odonatoid orders and suborders: Tarsophlebiidae (the closest sister group of Odonata, previously placed as a family within ‘Anisozygoptera’), Archizygoptera, Protanisoptera, Protodonata and Geroptera. Parsimony analysis of the data, in which characters were treated both under equal weights and implied weighting, produced cladograms that were highly congruent, and in spite of considerable homoplasy in the odonate data, many groupings in the most parsimonious cladograms were well supported in all analyses, as indicated by Bremer support. The analyses supported the monophyly of both Anisoptera and Zygoptera, contrary to the well known hypothesis of zygopteran paraphyly. Within Zygoptera, two large sister clades were indicated, one comprised of the classical (Selysian) Calopterygoidea, except that Amphipterygidae, which have traditionally been placed as a calopterygoid family, nested within the other large zygopteran clade comprised of Fraser's ‘Lestinoidea’ plus ‘Coenagrionoidea’ (both of which were shown to be paraphyletic as currently defined).Philogangaalone appeared as the sister group to the rest of the Zygoptera in unweighted cladograms, whereasPhiloganga + Diphlebiacomprised the sister group to the remaining Zygoptera in all weighted cladograms. ‘Anisozygoptera’ was confirmed as a paraphyletic assemblage that forms a ‘grade’ towards the true Anisoptera, withEpiophlebiaas the most basal taxon. Within Anisoptera, Petaluridae appeared as the sister group to other dragonflies.

BackgroundA skewed assemblage of two epi-, meso- and bathypelagic fish families makes up the order Myctophiformes – the blackchins Neoscopelidae and the lanternfishes Myctophidae. The six rare neoscopelids show few morphological specializations whereas the divergent myctophids have evolved into about 250 species, of which many show massive abundances and wide distributions. In fact, Myctophidae is by far the most abundant fish family in the world, with plausible estimates of more than half of the oceans combined fish biomass. Myctophids possess a unique communication system of species-specific photophore patterns and traditional intrafamilial classification has been established to reflect arrangements of photophores. Myctophids present the most diverse array of larval body forms found in fishes although this attribute has both corroborated and confounded phylogenetic hypotheses based on adult morphology. No molecular phylogeny is available for Myctophiformes, despite their importance within all ocean trophic cycles, open-ocean speciation and as an important part of neoteleost divergence. This study attempts to resolve major myctophiform phylogenies from both mitogenomic sequences and corroborating evidence in the form of unique mitochondrial gene order rearrangements.ResultsMitogenomic evidence from DNA sequences and unique gene orders are highly congruent concerning phylogenetic resolution on several myctophiform classification levels, corroborating evidence from osteology, larval ontogeny and photophore patterns, although the lack of larval morphological characters within the subfamily Lampanyctinae stands out. Neoscopelidae is resolved as the sister family to myctophids with Solivomer arenidens positioned as a sister taxon to the remaining neoscopelids. The enigmatic Notolychnus valdiviae is placed as a sister taxon to all other myctophids and exhibits an unusual second copy of the tRNA-Met gene – a gene order rearrangement reminiscent of that found in the tribe Diaphini although our analyses show it to be independently derived. Most tribes are resolved in accordance with adult morphology although Gonichthyini is found within a subclade of the tribe Myctophini consisting of ctenoid scaled species. Mitogenomic sequence data from this study recognize 10 reciprocally monophyletic lineages within Myctophidae, with five of these clades delimited from additional rearranged gene orders or intergenic non-coding sequences.ConclusionsMitogenomic results from DNA sequences and unique gene orders corroborate morphology in phylogeny reconstruction and provide a likely scenario for the phylogenetic history of Myctophiformes. The extent of gene order rearrangements found within the mitochondrial genomes of myctophids is unique for phylogenetic purposes.

Phylogenetic analyses testing the monophyly of the tribe Hydrobiusini and the relationships among its genera are performed based on a data matrix including characters of larval morphology and morphometrics, larval chaetotaxy and adult morphology, including eight of the nine hydrobiusine genera plus 15 outgroup taxa. The head chaetotaxy of six genera of the tribe Hydrobiusini is described (Ametor, Hybogralius, Hydramara, Limnohydrobius, Limnoxenus and Sperchopsis). Morphometric characters derived from the head capsule and mouthparts are included. All characters are illustrated in detail. The analyses performed on the above datasets and their combinations reveal the monophyly of the Hydrobiusini except for Hybogralius, and reconstruct the internal topology of the tribe, largely corresponding to results of previous molecular analyses. Hybogralius groups with genera having larvae adapted to underwater feeding in all analyses. The position of the genus Tritonus within the Laccobiini is questioned by our analyses, which suggest a closer relationship with the tribes Hydrophilini or Hydrobiusini. Larval characters are revealed as highly homoplastic, with chaetotaxic characters performing slightly worse than usual larval morphology. Nonetheless, they are phylogenetically informative and useful for testing phylogenetic hypotheses resulting from analyses of molecules or adult morphology. A key to larvae of the genera of the Hydrobiusini is presented.

BackgroundDNA barcoding of life using a standardized COI sequence was proposed as a species identification system, and as a method for detecting putative new species. Previous tests in birds showed that individuals can be correctly assigned to species in ~94% of the cases and suggested a threshold of 10× mean intraspecific difference to detect potential new species. However, these tests were criticized because they were based on a single maternally inherited gene rather than multiple nuclear genes, did not compare phylogenetically identified sister species, and thus likely overestimated the efficacy of DNA barcodes in identifying species.ResultsTo test the efficacy of DNA barcodes we compared ~650 bp of COI in 60 sister-species pairs identified in multigene phylogenies from 10 orders of birds. In all pairs, individuals of each species were monophyletic in a neighbor-joining (NJ) tree, and each species possessed fixed mutational differences distinguishing them from their sister species. Consequently, individuals were correctly assigned to species using a statistical coalescent framework. A coalescent test of taxonomic distinctiveness based on chance occurrence of reciprocal monophyly in two lineages was verified in known sister species, and used to identify recently separated lineages that represent putative species. This approach avoids the use of a universal distance cutoff which is invalidated by variation in times to common ancestry of sister species and in rates of evolution.ConclusionClosely related sister species of birds can be identified reliably by barcodes of fixed diagnostic substitutions in COI sequences, verifying coalescent-based statistical tests of reciprocal monophyly for taxonomic distinctiveness. Contrary to recent criticisms, a single DNA barcode is a rapid way to discover monophyletic lineages within a metapopulation that might represent undiscovered cryptic species, as envisaged in the unified species concept. This identifies a smaller set of lineages that can also be tested independently for species status with multiple nuclear gene approaches and other phenotypic characters.

Species of the genus Himalopsyche (Trichoptera, Rhyacophilidae) inhabit alpine to montane environments in Central and East Asia and North America. Diversity of the genus is concentrated primarily in the Himalayas and surrounding mountain ranges. Phylogenetic hypotheses have hitherto been proposed based on morphological data. Here, we present the first molecular phylogeny of Himalopsyche based on six gene fragments, using three methods of phylogenetic inference. Based on the phylogenetic analyses, we re‐evaluated species groups suggested by previous authors based on adult male morphology. We found that the previously defined groups are largely supported by molecular evidence as well as larval and adult morphology. However, we modify the species groups so that Himalopsyche phryganea and Himalopsyche lepcha constitute monotypic groups, and so that the tibetana group and anomala group sensu Schmid & Botosaneanu are merged to a single group, here defined as the tibetana group. Thus, we propose that Himalopsyche can be divided into five groups: kuldschensis group, lepcha group, navasi group, phryganea group, and tibetana group. We also provide a biogeographic synthesis of Himalopsyche distributions.

Taxonomy: DNA barcodes: recent successes and future prospects

Abstract. Larvae of the staphylinid subfamily Trichophyinae are described for the first time based on larvae of a new species of Trichophya from the southwestern United States. Adults and larvae of the new species, Trichophya texana Ashe & Newton (type locality Texas, Brewster Co., Big Bend National Park), are described and illustrations of both provided. Also given are a key for separation of the Nearctic species of Trichophya , a checklist of the known World fauna of the Trichophyinae (including first report of the genus from Mexico and Guatemala), and a characterization of the subfamily Trichophyinae based on both larvae and adults. The relationships of major genera and higher taxa in the tachyporine group of staphylinid subfamilies are analysed cladistically using larval characters. No larval characters were found that provide evidence for the monophyly of the tachyporine group; no evidence was found for the monophyly of the Tachyporinae; Charhyphus, Olisthaerus and Phloeocharis (Phloeocharinae + Olisthaerinae) form a monophyletic group; the Trichophyinae and Habrocerinae are sister groups and together probably are the sister group to the Aleocharinae; the Aleocharinae are confirmed to be monophyletic based on larval characters; and Gymnusa + Deinopsis form the sister group to the remainder of the Aleocharinae.

Apiomithrax violaceus (A. Milne Edwards, 1868) is a pisid majoid crab occurring in tropical and subtropical coastal waters of the eastern and western South Atlantic. Larval development consists of two zoeal stages and a megalopa. Beginning with the first zoea, the duration of each larval stage at 24°C was 3–8 (5±1), 3–5 (4±0.5) and 9–15 (11±2) days, the megalopa and first crab instar appearing 9–11 (10±1) and 20–27 (23±2) days after hatching, respectively. Larval characters agree with those proposed for the Majoidea, in having nine or more setae on the scaphognathite in the first zoea and well-developed pleopods in the second zoea. However, larvae of A. violaceus do not fit larval pisid features. Zoeal stages differ from most other Pisidae in having lateral spines, a long rostral spine extending beyond the antenna, two spines per telson fork and a dorsolateral process on the third abdominal somite. The megalopa differs in having a spine dorsally on the carapace and on the basial segment of the second pereiopod. Two characters that are potentially unique to Apiomithrax include a zoeal antenna with an exopod that is much longer than the protopod, and a rostral spine that is longer than the dorsal spine. These characters should facilitate the identification of this taxon and could also be useful for phylogenetic studies. A review of larvae of 28 species among 14 genera indicated that there is no apparent single larval character that differentiates the Pisidae, with more limited phylogenetic analyses suggesting that this is a paraphyletic group. Apiomithrax, Eurynolambrus, Pisoides, Rochinia and Scyra have the most divergent morphological characters within the family. The analysis and inclusion of additional taxa is likely to shed more light on the sister-group relationships of the Pisidae. However, based on the extent of morphological interspecific variability of known larvae it is likely that the group, as presently defined by adult morphology, is not monophyletic.

Leptopeltus trogloxenus López-Prada Chani-Posse, a new species of the subtribe Philonthina (tribe Staphylinini) from the Andes of Colombia, is described and illustrated. A dataset of 49 morphological characters scored for 10 taxa, including all currently known species of Leptopeltus Bernhauer and its putative sister group, Leptopeltoides Chani-Posse Asenjo, was prepared and analysed by maximum parsimony. Our analysis unambiguously placed L. trogloxenus within Leptopeltus in a sister-group relationship with a clade of four species. A revised key to species and an updated phylogeny of Leptopeltus are also provided.

The differences in adult morphology of the denticles and tip of spicules revealed by the use of Scanning Electron Microscope,, and the difference in number of larvae recovered from the same number of eggs in the two species suggest they are different species, i.e. Ascaris lumbricoides Linnaeus, 1758 and Ascaris suum Goeze, 1782. In both species it was confirmed that two moults occur in the egg with the time interval elapsing between the two moults. It was concluded that the so-called second moult observed in the tissue of experimentally infected animals by various investigators represents a delayed process which commences in the egg and usually is completed before migration commences. The growth, development, distribution and migratory behaviour of the larvae of the two species are similar. The third-stage larvae of 8 species of Ophidascaris occurring in pythons were distinguished morphologically corresponding with differences in their growth and migratory behaviour in the tissue of mice. These differences in larval morphology and behaviour support their status as separate species.Toxocara hippopotami is described from a hippopotamus and found to have affinities with Toxocara vitutorum. A previous key to species of Toxocara is revised. Ophidascaris solitaria is redescribed from a closely related host collected from, the same locality as the original specimen. The species is compared with others in colubrine snakes. The status of Ophidascaris amucronata Schuurrnans-Stekhoven, 1937 was studied by a comparison with O. filaria sensu stricto (Dujardin, 1845) Sprent, 1969 on the basis of adult morphology and differentiation of larvae. Specimens of Polydelphis anoura from various hosts and locations did not show any morphological difference in adults or larval stages, suggesting that one species is involved in pythons. The three species of Hexametra occurring in Africa, South America, and Southeast Asia were compared in relation to adult morphology and larval characters and it was concluded that the three species, quadricornis, hexauterina and sewelli should be upheld.

Staphylinidae, or rove beetles, are one of the mega-diverse and abundant families of the ground-living terrestrial arthropods that is taxonomically poorly known even in the regions adjacent to Europe where the fauna has been investigated for the longest time. Since DNA barcoding is a tool to accelerate biodiversity research, here we explored if the currently-available COI barcode libraries are representative enough for the study of rove beetles of West Siberia. This is a vast region adjacent to Europe with poorly-known fauna of rove beetles and from where not a single DNA barcode has hitherto been produced for Staphylinidae. First, we investigated the faunal similarity between the rove beetle faunas of the climatically compatible West Siberia in Asia, Fennoscandia in Europe and Canada and Alaska in North America. Second, we investigated barcodes available for Staphylinidae from the latter two regions in BOLD and GenBank, the world's largest DNA barcode libraries. We conclude that the rather different rove beetle faunas of Fennoscandia, on the one hand and Canada and Alaska on the other hand, are well covered in both barcode libraries that complement each other. We also find that even without any barcodes originating from specimens collected in West Siberia, this coverage is helpful for the study of rove beetles there due to the significant number of widespread species shared between West Siberia and Fennoscandia and due to the even larger number of shared genera amongst all three investigated regions. For the first time, we compiled a literature-based checklist for 726 species of the West Siberian Staphylinidae supplemented by their occurrence dataset submitted to GBIF. Our script written for mining unique (i.e. not redundant) barcodes for a given geographic area across global libraries is made available here and can be adopted for any other regions.