Unresolved Species Complex Research Articles

Assessment of nine markers for phylogeny, species and haplotype identification of Kappaphycus species and Eucheuma denticulatum (Solieriaceae, Rhodophyta)

ABSTRACT Molecular studies have contributed to the taxonomy of carrageenan-producing Kappaphycus spp. and Eucheuma denticulatum. However, unresolved species complexes and the lack of standardization in the use of genetic markers impede the identification of specimens and the delineation of a robust taxonomic framework. Here, nine molecular markers (cox1, cox2–3 spacer, cox2, cox3, COB, ITS, psbA, UPA and rbcL) were used to generate a multilocus phylogeny for 113 fresh eucheumatoid samples and four herbarium specimens. Analyses of species delineation and genetic distances confirmed the monophyly of currently accepted taxa. These analyses suggest that clades previously reported as K. striatus KS1 and KS2 are conspecific, and that E. denticulatum EDA ‘spinosum’ and EDB ‘endong/cacing’ are also conspecific. The results also unveiled possible new taxa from Hawaii and Indonesia. Each molecular marker and combinations thereof were assessed with regard to species identification, ease of amplification and sequencing, and haplotype characterization. All genetic markers recorded at least 94% success in the amplification and sequencing of fresh specimens, with cox1 being the most phylogenetically informative. Automatic partitioning, phylogenetic and tree-based assessments showed cox1, cox2–3 spacer, cox2 and rbcL were able to correctly identify species while cox1+ rbcL, COB+rbcL, cox2+ rbcL or cox1+ COB+rbcL trees best represented the phylogeny with consistently high nodal support. Among individual markers, cox1 identified the greatest number of haplotypes, while UPA, partial rbcL (750 bp), ITS, cox3 and cox2–3 spacer were able to retrieve information from herbarium specimens of 12–16 years of age. These molecular results provide a basis for a database essential for the taxonomic framework, cultivar development and germplasm conservation of eucheumatoids.

Evolutionary history of Magnolia sect. Talauma (Magnoliaceae) in Cuba

Abstract Evolutionary biologists recognize that understanding the phylogenetic history of closely related species is challenging without considering their population genetics history. The taxonomy of Magnolia sect. Talauma in Cuba has long been debated, with several changes in taxon delimitations. All these taxonomic revisions were based exclusively on leaf morphological characteristics of a few individuals, limiting their ability to elucidate taxon boundaries. Recent studies have focused on conservation genetics and species delimitation of Cuban magnolias, based on ecological, morphological and genetic data. Here, we use full plastome sequences and microsatellite data to infer phylogenetic relationships and potential historical migration events among species in Magnolia sect. Talauma in Cuba. Bayesian phylogeny and TreeMix were used to understand the phylogenetic relationships. Based on this, Magnolia sect. Talauma in Cuba does not comprise a monophyletic group. The data continue to show a highly supported unresolved species complex in the taxa of Magnolia subsect. Talauma from north-eastern Cuba. From a taxonomic point of view, our results do not entirely support the most recent taxonomic review proposed for the family in Cuba.

Revision of Litoria rothii (Anura: Pelodryadidae) from northern Australia.

Litoria rothii is a widespread pelodryadid frog with a charismatic laughing advertisement call, distributed across the Australian Monsoon Tropics and southern New Guinea. Given its large distribution spanning well-known biogeographic barriers, variation in male advertisement calls and the prevalence of unresolved species complexes in the Australian frog fauna, we examine the genetic, morphological and acoustic diversity in the species from across its range. Our analyses reveal the presence of a previously unrecognised species in western parts of the range of L. rothii sensu lato, which we describe herein as a new species. Litoria ridibunda sp. nov. is distinguished from L. rothii on the basis of paraphyly of nuclear gene trees with L. everetti from Indonesia, colour patterns on the posterior thigh and male advertisement calls. Compared to L. rothii, the new species has a less contrasting pattern on the posterior thigh and a male advertisement call with a greater number of notes per call and a greater call duration. In particular, the magnitude of call differences between the species is highest where the ranges of the two species are in proximity in north-western Queensland. Our study further emphasises the undiagnosed diversity that remains in Australian frogs, even in relatively large, charismatic, frequently encountered species that often share human dwellings.

Ploidy variation in Rhododendron subsection Maddenia and its implications for conservation.

Polyploidy, which is common in plants, can confound taxon recognition and hence conservation assessments. In the taxonomically complex genus Rhododendron, 25 % of the over 1,300 taxa are considered under threat and 27 % Near Threatened or Data Deficient, with their taxonomy needing to be resolved urgently. Although ploidy levels of Rhododendron taxa range from diploid (2x) to dodecaploid (12x) according to previous reports, the extent of polyploidy across the genus has not been examined. We first summarized the taxonomic distribution of polyploids in the genus based on the literature. Then as a case study, we estimated ploidy levels of 47 taxa in subsection Maddenia (subgenus Rhododendron, section Rhododendron) using flow cytometry, together with verification of meiotic chromosome counts for representative taxa. The summary of reported ploidy in Rhododendron indicates that polyploidy is most common in subgenera Pentanthera and Rhododendron. In subsection Maddenia, all examined taxa are diploids except for the R. maddenii complex that shows a high ploidy variation (2-8x, 12x). We investigated ploidy level of 12 taxa in subsection Maddenia for the first time, and estimated genome sizes of two Rhododendron species. Knowledge of ploidy levels will inform phylogenetic analysis of unresolved species complexes. Overall, our study of subsection Maddenia provides a model for examining multiple issues including taxonomic complexity, ploidy variation and geographic distribution in relation to biodiversity conservation.

Phylogenomic inference of two widespread European leaf miner species complexes suggests mechanisms for sympatric speciation (Lepidoptera: Nepticulidae: Ectoedemia)

AbstractLeafmining insects have extraordinarily intimate relationships with their host plants and are therefore prime candidates for potential ecological speciation in sympatry, but how commonly this mode of speciation occurs in any group of life remains debated. Prior research on the pygmy moth (Nepticulidae) genus Ectoedemia using morphology, DNA barcoding, and multi‐marker phylogenetic approaches left two unresolved species complexes, each with each four described species. In this study, we thoroughly sampled each complex across a range of host plants and localities across Europe. We used a double digest restriction‐site associated DNA (ddRAD) sequencing approach to clarify species boundaries. In the E. rubivora complex, ddRAD data resolved all four species, contrary to morphological and COI data, which supports a potential scenario of host plant‐driven speciation where the host plant specialization provides an ecological barrier to hybridization. However, we found no indication of host race formation within the oligophagous E. atricollis (Stainton). In the E. subbimaculella complex, SNP data only partly distinguishes between the parapatric E. subbimaculella (Haworth) and E. heringi (Toll), but with some statistical overlap, suggesting incomplete lineage sorting which may represent early phases of host‐based ecological speciation, or admixture following a period of isolation.

Infection of papaya (Carica papaya) by four powdery mildew fungi

Papaya (Carica papaya L.) is an important fruit crop in many tropical and subtropical countries. Powdery mildew commonly affects this host, causing premature leaf loss, reduced yields and poor fruit quality. At least fifteen different fungi have been identified as the causal agents of papaya powdery mildew. Powdery mildew symptoms were detected on potted papaya plants growing in two locations in Hungary. This study aimed to identify the causal agents. Morphology of powdery mildew samples was examined, and sequences of two loci were used for molecular taxonomic identifications. Only anamophs were detected in all samples, and four morphological types were distinguished. Most samples had Pseudoidium anamorphs, while some were of the Fibroidium anamorph. Based on morphology and molecular taxonomy, the Fibroidium anamorph was identified as Podosphaera xanthii. The Pseudoidium anamorphs corresponded to three different Erysiphe species: E. cruciferarum, E. necator and an unidentified Erysiphe sp., for which molecular phylogenetic analyses showed it belonged to an unresolved species complex of E. malvae, E. heraclei and E. betae. Infectivity of P. xanthii and E. necator on papaya was verified with cross inoculations. A review of previous records of powdery mildew fungi infecting papaya is also provided. Podosphaera xanthii was known to infect, and E. cruciferarum was suspected to infect Carica papaya, while E. necator was recorded on this host only once previously. No powdery mildew fungus belonging to the E. malvae/E. heraclei/E. betae species complex is known to infect papaya or any other plants in the Caricaceae, so the unidentified Erysiphe sp. is a new record on papaya and the Caricaceae. This study indicates host range expansion of this powdery mildew fungus onto papaya.

Taxonomic clarification of two Cercospora spp. causing leaf spots on Neomarica spp. in Brazil

Neomarica is a genus of the Iridaceae with several ornamental species, including Neomarica caerulea (walking iris) and N. longifolia (yellow iris). Little is known about fungal diseases of members of the genus Neomarica. In June 2017, N. longifolia plants growing in a garden at Antonio Carlos were observed bearing leaf spots symptoms. A cercosporoid hyphomycete was associated with the necrotic tissues. It was conjectured that the fungus involved might be the same described causing leaf spots on N. caerulea in Brazil. Examination of the type of the species concerned (Cercospora neomaricae) revealed that this specimen was in very poor condition and inadequate for comparison. This prompted us to re-collect the fungus from the type locality for epitypification. Besides designating an epitype, a pure culture of C. neomaricae was obtained (ex-epitype culture) and a molecular study of this isolate together with the molecular and morphological analysis of the fungus on N. longifolia was performed. The fungus on N. longifolia was found to be morphologically and genetically clearly distinct from C. neomaricae. Analyses of the ITS, CAL and ACT regions indicated that the fungus on N. longifolia belongs to the Cercospora sp. H, which is an unresolved species complex, including several isolates obtained from various hosts.

Corallite skeletal morphological variation in Hawaiian Porites lobata

Due to their high morphological plasticity and complex evolutionary history, the species boundaries of many reef-building corals are poorly understood. The skeletal structures of corals have traditionally been used for species identification, but these structures can be highly variable, and currently we lack knowledge regarding the extent of morphological variation within species. Porites species are notorious for their taxonomic difficulties, both morphologically and genetically, and currently there are several unresolved species complexes in the Pacific. Despite its ubiquitous presence and broad use in coral research, Porites lobata belongs to one such unresolved species complex. To understand the degree of intraspecific variation in skeletal morphology, 120 corallites from the Hawaiian P. lobata were examined. A subset of samples from two genetically differentiated populations from contrasting high- and low-stress environments in Maunalua Bay, Hawaii, were then quantitatively analyzed using multivariate morphometrics. Our observations revealed high intraspecific variation in corallite morphology, as well as significant morphological differences between the two populations of P. lobata. Additionally, significant correlation was found between the morphological and genetic distances calculated from approximately 18,000 loci generated from restriction site-associated DNA sequencing. The unique morphological characters observed from the genetically differentiated population under environmental stress suggest that these characters may have adaptive values, but how such traits relate to fitness and how much plasticity they can exhibit remain to be determined by future studies. Relatively simple morphometric analyses used in our study can be useful in clarifying the existing ambiguity in skeletal architecture, thus contributing to resolving species issues in corals.

Species complexes within epiphytic diatoms and their relevance for the bioindication of trophic status

The popularity of aquatic bioassessments has increased in Europe and worldwide, with a considerable number of methods being based on benthic diatoms. Recent evidence from molecular data and mating experiments has shown that some traditional diatom morphospecies represent species complexes, containing several to many cryptic species. This case study is based on epiphytic diatom and environmental data from shallow fishponds, investigating whether the recognition and use of fine taxonomic resolution (cryptic species) can improve assessment of community response to environmental drivers and increase sharpness of classification, compared to coarse taxonomic resolution (genus level and species level with unresolved species complexes). Secondly, trophy bioindication based on a species matrix divided into two compartments (species complexes and remaining species) was evaluated against the expectation that species complexes would be poor trophy indicators, due to their expected wide ecological amplitude. Finally, the response of species complexes and their members (cryptic species) to a trophic gradient (phosphorus) were compared.Multivariate analyses showed similar efficiency of all three taxonomic resolutions in depicting community patterns and their environmental correlates, suggesting that even genus level resolution is sufficient for routine bioassessment of shallow fishponds with a wide trophic range. However, after controlling for coarse taxonomic matrices, fine taxonomic resolution (with resolved cryptic species) still showed sufficient variance related to the environmental variable (habitat groups), and increased the sharpness of classification, number of indicator species for habitat categories, and gave better separation of habitat categories in the ordination space. Regression analysis of trophic bioindication and phosphorus concentration showed a weak relationship for species complexes but a close relationship for the remaining taxa. GLM models also showed that no species complex responded to phosphorus concentration. It follows that the studied species complexes have wide tolerances to, and no apparent optima for, phosphorus concentrations. In contrast, various responses (linear, unimodal, or no response) of cryptic species within species complexes were found to total phosphorus concentration. In some cases, fine taxonomic resolution to species level including cryptic species has the potential to improve data interpretation and extrapolation, supporting recent views of species surrogacy.

Novel species of Gliocladiopsis (Nectriaceae, Hypocreales, Ascomycota) from avocado roots (Persea americana) in Australia

Root rot of avocado (Persea americana) is an important disease in seedling nurseries as well as in the field in eastern and southern Australia. During an investigation into the causal organisms of avocado root rot, 19 isolates of Gliocladiopsis were obtained from necrotic lesions on avocado roots and examined by morphology and comparison of DNA sequences from three gene loci (the internal transcribed spacer region of the nuclear rDNA, Histone H3 and β-tubulin). Three new species of Gliocladiopsis are described as a result of phylogenetic analysis of these data. One of the new species, G. peggii, formed a monophyletic group that may represent an unresolved species complex as it contained a polytomy that included a well-supported clade comprising two subclades. Gliocladiopsis peggii is sister to G. mexicana, which is known from soil in Mexico. The remaining two new species, G. whileyi and G. forsbergii, formed a clade sister to G. curvata, which is known from Ecuador, Indonesia and New Zealand.

A New Species of Genus Plakortis Schulze 1880 (Porifera: Homoscleromorpha) from Badabalu, Andaman and Nicobar Islands, India.

Vibha V. Ubare and PM. Mohan (2016) Recently revealed Class: Homoscleromorpha play a significant role in sponge systematics. The smaller size, cryptic habits and unresolved species complex are greater obstacles for the taxonomic identification of this class. Out of < 100 species, only 6 species have been described from the Indian region. Till date, only one species of the genus Plakortis, that is, P. simplex has been described from this region. The present study provides a detailed description of new species of the genus Plakortis, Schulze 1880. P. badabaluensis sp. nov. is characterized by the two size classes of diods (one is thick and the other is thin), triods and smooth microrhabds; with well differentiated ectosome, presence of subectosomal lacunae and confused choanosome. The identification of this new species has increased the number of plakinid species from one to two in the Andaman and Nicobar Islands, India. Further detailed studies are required to explore this type of cryptic species in this region.

A synopsis of the exindusiate species of Cyathea (Cyatheaceae-Polypodiopsida) with bipinnate-pinnatifid or more complex fronds, with a revision of the C. lasiosora complex

A summary of the Neotropical exindusiate species of Cyathea with bipinnate-pinnatifid or more complex fronds is presented. It is a polyphyletic group containing species of the obsolete genera Trichipteris and Sphaeropteris subg. Sclephropteris with several unresolved species complexes, like Cyathea lasiosora and C. pilosissima from the eastern Andean foothills and the Amazonian lowland. This study shows that their confusion is mainly due to intraspecific variability in the abundance of laminar hairs in C. lasiosora, which overlaps with that of C. pilosissima, and that the latter species is less frequently collected than the former. With sufficient material at hand, both stand clearly apart in petiolar characters, e.g., C. lasiosora lacking hairs here vs. C. pilosissima with hairs 1–3 mm long. A close relationship of C. pilosissima with species of the obsolete, artificial Sphaeropteris senilis group (C. senilis, C. parianensis, C. lockwoodiana) is discussed. Cyathea lasiosora (Amazon basin) forms a parapatric species complex with C. wendlandii (Central America and Chocó), C. schlimii (northern Andes) and C. atrocastanea (eastern Brazil). A taxon that shares the petiole morphology with C. lasiosora and the laminar morphology with C. lockwoodiana is separated as a new species: Cyathea calamitatis. Further described are C. diabolica from southern Ecuador and C. margarita from western Colombia and Ecuador.

Delimiting the species within the genus Austroplebeia, an Australian stingless bee, using multiple methodologies

Austroplebeia Moure is an Australian stingless bee genus. The current descriptions for the species within this genus are inadequate for the identification of specimens in either the field or the laboratory. Here, using multiple diagnostic methodologies, we attempted to better delimit morphologically identified groups within Austroplebeia. First, morphological data, based on worker bee colour, size and pilosity, were analysed. Then, males collected from nests representing morphologically similar groups were dissected, and their genitalia were imaged using light microscopy and scanning electron microscopy. Next, data for the geometric morphometric analysis of worker wing venations were obtained. Finally, molecular analysis, using mitochondrial 16S ribosomal RNA (16S rDNA), was conducted on workers from representative nests for each group which displayed morphological similarities. Data deriving from the four different diagnostic approaches were compared, resulting in the separation of two groups, plus an unresolved species complex.

Using DNA taxonomy to investigate the ecological determinants of plankton diversity: explaining the occurrence of Synchaeta spp. (Rotifera, Monogononta) in mountain lakes

Summary1. The occurrence of unresolved complexes of cryptic species may hinder the identification of the main ecological drivers of biodiversity when different cryptic taxa have different ecological requirements.2. We assessed factors influencing the occurrence of Synchaeta species (monogonont rotifers) in 17 waterbodies of the Trentino‐South Tyrol region in the Eastern Alps. To do so, we compared the results of using unresolved complexes of cryptic species, as is common practice in limnological studies based on morphological taxonomy, and having resolved cryptic complexes, made possible by DNA taxonomy.3. To identify cryptic species, we used the generalised mixed Yule coalescent (GMYC) model. We investigated the relationship between the environment and the occurrence of Synchaeta spp. by multivariate ordination using two definitions of the units of diversity, namely (i) unresolved species complexes (morphospecies) and (ii) putative cryptic species (GMYC entities). Our expectation was that resolving complexes of cryptic species could provide more information than using morphospecies.4. As expected, DNA taxonomy provided greater taxonomic resolution than morphological taxonomy. Further, environmental‐based multivariate ordination on cryptic species explained a significantly higher proportion of variance than that based on morphospecies. Occurrence of GMYC entities was related to total phosphorus (TP), whereas no relationship could be found between morphospecies and the environment. Moreover, different cryptic species within the same morphospecies showed different, and even opposite, preferences for TP. In addition, the wide geographical distribution of haplotypes and cryptic species indicated the absence of barriers to dispersal in Synchaeta.

Taxonomic confusion of two tramp ant species: Iridomyrmex anceps and Ochetellus glaber are really species complexes

Abstract Many invasive invertebrates belong to unresolved species complexes, and have a history of misidentification and inappropriate management. Here we detail confusion surrounding the taxonomy and identification of two dolichoderine ant species, Iridomyrmex anceps Roger and Ochetellus glaber Mayr, which are commonly cited in the literature as having been spread widely by human commerce. We provide morphometric data and images strongly suggesting that these two “species” are instead complexes of species that are likely native to many regions where they are purportedly introduced. We take particular interest in the status of species referred to as I. anceps and O. glaber in China, as this is the most northerly distribution of both genera. We conclude by suggesting that many identifications of both species are likely to be unreliable, and we recommend against any management action aimed at controlling these species under the assumption that they are exotic.

Systematics of the Onychoteuthidae Gray, 1847 (Cephalopoda: Oegopsida)

Squids in the family Onychoteuthidae Gray, 1847, have been reported from every ocean but the Arctic, are taken frequently in deep-sea fisheries bycatch, and are ecologically important in the diets of many marine predators including cetaceans, pinnipeds, sharks, and seabirds. However, the diversity and systematics of the family have remained poorly understood. Of the 60+ nominal species, 12–14 have generally been accepted in recent studies. Challenges to clarity include insufficient species descriptions, original descriptions published in eight languages and often based solely on early life stages, non-designation or subsequent loss of type material, and the existence of several unresolved species complexes. In light of the general systematic disarray of the Onychoteuthidae, a global revision of the family follows, based on ~1500 specimens examined from 19 repositories. Type material has been examined wherever possible (although, for some species, photographs of type specimens, original illustrations, and/or the original descriptions have provided the only information available). For all 25 species treated in this revision, descriptions and illustrations are provided to a consistent standard that will enable their reidentification. External and internal morphological characters and states are described for subadult to adult stages of most species, with external characters reported through ontogeny as permitted by available material. Historically important characters are treated (general external morphology, body proportions, tentacle clubs, photophores, gladius, lower beak, radula), augmented by several more recently recognised characters (palatine teeth, detailed morphology of the tentacular hooks in adults, tentacular suckers in paralarvae, chromatophore patterns). The systematic value of both historical and new morphological characters at the generic and species levels is discussed; at all ontogenetic stages, tentacular club and hook morphology are considered the most valuable characters, although body proportions and gladius also prove useful. In the interest of systematic stability, neotypes are also designated for four species in which type specimens were not previously designated [Onykia (Onykia) loennbergii Ishikawa &amp; Wakiya, 1914; Onychoteuthis borealijaponica Okada, 1927] or have been subsequently lost [Onykia (Onykia) carriboea Lesueur, 1821; Onykia (Onykia) robsoni Adam, 1962]. Partial resolution of the Onychoteuthis banksii complex has been possible in the Pacific and Atlantic Oceans, resulting in: the resurrection of Onychoteuthis bergii Lichtenstein, 1818, and Onychoteuthis aequimanus Gabb, 1868; the description of two new species in an earlier publication (Onychoteuthis lacrima Bolstad &amp; Seki, and Onychoteuthis prolata Bolstad, Vecchione &amp; Young, in Bolstad, 2008) and another herein, Onychoteuthis horstkottei sp. nov.; and the expansion of one species’ recognised distribution (Onychoteuthis compacta Berry, 1913) to include the Atlantic Ocean. The genus Moroteuthis Verrill, 1881, is considered a junior synonym of Onykia Lesueur, 1821, in accordance with the findings of several earlier authors. However, morphological differences in the species ‘Moroteuthis’ ingens Smith, 1881, necessitate the resurrection of the subgenus Moroteuthopsis Pfeffer, 1908, with all other Onykia species placed into the nominate subgenus Onykia (Onykia). Sexual dimorphism is reported in the beaks of Onykia (Moroteuthopsis) ingens (new comb.). Morphological and historical genetic data suggest a more distant relationship between Onykia and the species ‘Moroteuthis’ knipovitchi Filippova, 1972, than was suggested by earlier classifications. This species is therefore placed into Filippovia gen. nov., described herein. ‘Onykia’ rancureli (Okutani, 1981) and C. youngorum sp. nov. are placed into Callimachus gen. nov., according to morphological and genetic data. Given that the majority of available onychoteuthid material was collected after 1950, resulting in the descriptions of over half of the generally accepted genera and species since 1960, ongoing collection programmes are necessary to further resolve onychoteuthid systematics.

Lactarius volemus sensu lato (Russulales) from northern Thailand: morphological and phylogenetic species concepts explored

Lactarius volemus (Fr.: Fr.) Fr. is a well known and morphologically easily recognizable milkcap of the Northern hemisphere, forming ectomycorrhiza with both deciduous and coniferous trees. It was originally described from Europe, but is also reported in other continents. Although it is characterized by several unique macro- and micromorphological features, substantial variation in colour, lamellae spacing and changing and staining of the latex has been recorded and it is therefore considered as a putatively unresolved species complex. This study explores the concordance between morphological and phylogenetic species concepts within L. volemus sensu lato of northern Thailand, combining a critical morphological scrutiny with a multiple gene genealogy based on LSU, ITS and rpb2 nuclear sequences. Twelve strongly supported monophyletic clades and six terminal branches are discernable in all phylogenetic trees and represent 18 phylogenetic species. Six of the monophyletic clades can be morphologically distinguished and are described as new species: L. acicularis, L. crocatus, L. distantifolius, L. longipilus, L. pinguis and L. vitellinus. Five other clades also show some morphological differences, but these are too subtle and do not allow for a clear-cut species delimitation without the corroboration of molecular data. Lactarius volemus sensu lato of northern Thailand is therefore still considered as a partially cryptic species complex. Pleurolamprocystidia, pileipellis hairs and to a lesser degree also pileus colour are important diagnostic characteristics. Spore morphology, latex discoloration and pileus surface texture are less useful as diagnostic features. Whether this rich diversity is the result of in situ Pleistocene survival or post-glacial expansion and subsequent radiation, has yet to be revealed.

A revision of the Australian handfishes (Lophiiformes: Brachionichthyidae), with descriptions of three new genera and nine new species

The family Brachionichthyidae is represented by at least 14 small, Australian endemic, lophiiform fishes distributed from central eastern Australia to the Great Australian Bight. All but three of these species occur in the seas off Tasmania. The group is comprised of two recognised genera, Brachionichthys Bleeker and Sympterichthys Gill, and three new genera, Brachiopsilus gen. nov., Pezichthys gen. nov. and Thymichthys gen. nov. Nine of the 14 species are undescribed. The type genus, Brachionichthys, consists of B. hirsutus (Lacepède) and B. australis Last, Gledhill &amp; Holmes. These species, which are covered with long, unicuspid spinules and a strong colour pattern of dark spots and streaks, typically have 7 pectoral-fin rays. The genus Sympterichthys includes one of Australia’s earliest described fishes, S. unipennis (Cuvier), and a new taxon S. moultoni sp. nov. Members of the genus lack warts and dermal appendages on the skin but are covered in small embedded scales with adpressed, unicuspid and bicuspid spinules originating from the posterior margin of their bases. Brachiopsilus contains three new species: B. dianthus sp. nov., B. dossenus sp. nov. and B. ziebelli sp. nov. These handfishes, which are amongst the largest members of the family (reaching 117 mm SL), are smooth skinned (without spinules, dermal appendages or fleshy warts), are vividly coloured in life (without extensive blackish markings), and have 9–10 pectoral-fin rays. A fourth genus, Pezichthys, is not fully resolved and may be polyphyletic. It provisionally consists of five undescribed species: P. amplispinus sp. nov., P. compressus sp. nov., P. eltanini sp. nov., P. macropinnis sp. nov. and P. nigrocilium sp. nov. These species are variably covered in erect, bicuspid spinules, and all have 7 pectoral-fin rays. Thymichthys contains two old species-level taxa, T. politus (Richardson) and T. verrucosus (McCulloch &amp; Waite), both previously placed in Sympterichthys. Members of the genus Thymichthys have an ornate skin variably covered with wart-like protuberances, dermal appendages and a sparse coverage of scales with their spinules not or barely penetrating the skin surface. Regional morphs exist for Thymichthys verrucosus which may represent an unresolved species complex. New study material and a molecular study of these populations across their ranges are needed to determine their relationships. Other characters useful in defining the brachionichthyid genera, and distinguishing species, include illicial morphology, coloration, characteristics of the skin, including the form and degree of coverage and exposure of spiny scales, and selected morphometrics and meristics. Historical and current ecological data confirms that these fishes have specialised habitat requirements, patchy distributions and poor dispersal capabilities, making them amongst the most vulnerable of marine fishes. The fossil record suggests that the group was once much more widespread and their restricted extant distribution in Australia may be linked to regional extinction due to their life history strategy.

Molecular and morphological evidence for the delimitation of Xylaria hypoxylon

Xylaria hypoxylon, the type species of Xylaria (Xylariaceae, Sordariomycetes), was first described by Linnaeus as Clavaria hypoxylon from Sweden. Saccardo and other mycologists assumed a cosmopolitan distribution for this species. However, contradictory reports in the literature on its morpho-anatomical characters and strongly inconsistent rDNA sequence data attributed to this species in GenBank suggested the existence of an unresolved species complex. To address this lack of clarity, molecular and morphological characters of numerous specimens and corresponding cultures of X. hypoxylon and related taxa from Europe were studied. Newly obtained 5.8S/ITS nrDNA sequence data were compared with published data and sequences of reference strains. European populations of X. hypoxylon from various hosts exhibited consistent rDNA sequence data and a relatively uniform holomorphic morphology, except for one specimen from Sweden that deviated in its ascospore morphology. Some samples from western United States showed DNA sequence data being identical to those of specimens from Europe, confirming a North American occurrence of X. hypoxylon. DNA sequences and morphology of other extra-European material however showed substantial deviations. Definitely not conspecific with the European material examined in this study is a strain, assigned to X. hypoxylon, the DNA sequence data of which have been used in various phylogenetic studies as a representative of Xylariaceae and Xylariales respectively. This material probably represents X. longiana.

Monocotylids (Monogenea: Monopisthocotylea) from Aetobatus cf. narinari off New Caledonia, with a description of Decacotyle elpora n. sp.

Four species of monocotylid monogeneans were found on a spotted eagle ray Aetobatus cf. narinari caught off Noumea, New Caledonia, South Pacific. The host is illustrated for future possible identification, because it belongs to a currently unresolved species complex. Decacotyle octona (Young, 1967) Chisholm & Whittington, 1998, from the secondary gill lamellae, is figured and previously unreported details of the reproductive system are described. D. elpora n. sp. is described from numerous specimens found between the secondary gill lamellae. The new species, 780-1650 microm in body length, is smaller than D. octona, but has a longer sclerotised male copulatory organ. It is characterised by two dorsal haptoral accessory structures, each with three bumps, and a 9-shaped sclerotised male copulatory organ 240-290 microm in length. D. octona and Clemacotyle australis Young, 1967, both from the branchial cavity, and Thaumatocotyle pseudodasybatis Hargis, 1955, from the nasal tissue, are new geographical records for New Caledonia. It is suggested that differences in the monocotylid fauna between the Atlantic and Indo-Pacific forms of Aetobatus cf. narinari could be of interest for the systematic status of the ray, but the sporadic nature of the sampling probably casts doubt on the usefulness of the currently available data.