Catalogue of Organisms

Time 2020-12-14 06:03:45

Web Name: Catalogue of Organisms

WebSite: http://coo.fieldofscience.com

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Water mites of the clade Hydrachnidiae are one of the few groups of arachnids that have not only adopted an aquatic lifestyle but have thrived and diversified there. Over fifty families are currently recognised within this clade, some of which can be found in almost every body of fresh water worldwide. Others, however, are notable for their restricted ranges. One of these latter examples is the Omartacaridae.Ventral view of female Omartacarus elongatus, from Cook (1963).Omartacaridae is a small family currently recognised as including only two genera, Omartacarus and Maharashtracarus. They have a somewhat elongated body with a soft integument, contrasting with the more globular form of many other water mites. They are also distinguished by the arrangement of the coxae (the basal segments of the legs on the underside of the body) which are clustered together with the medial edges of the anterior pairs much longer than those of the posterior pairs (Walter et al. 2009) so the third pair of coxae are triangular in shape. As far as is known, omartacarids are restricted to interstitial habitats or the hyporheic zone of sediment beneath and alongside stream beds. I am unaware of any direct observations of omartacarid behaviour but they are presumably predators like other water mites. Most of the (rather limited) attention that has been given to omartacarids has focused on discussions of their distribution. Species of Omartacarus are found in South and southern North America, as well as in Australia. Maharashtracarus species are known from India and Costa Rica. It has been presumed that this reflects an ancestral Gondwanan distribution, spreading into North America from South America as the continents joined.The larval stage of omartacarids is, to date, unknown. Larvae of other water mites live as parasites of water-associated insects such as midges and omartacarid larvae are presumably also parasitic. But in what capacity? Do mature omartacarids emerge from their subterranean habitats at some particular time of year in search of a host for their eggs? Do they somehow manage to find a host while remaining safely sequestered underground? The secret remains to be uncovered.REFERENCEWalter, D. E., E. E. Lindquist, I. M. Smith, D. R. Cook & G. W. Krantz. 2009. Order Trombidiformes. In: Krantz, G. W., & D. E. Walter (eds) A Manual of Acarology 3rd ed. pp. 233-420. Texas Tech University Press.Central and South America are home to a remarkable diversity of frogs, coming in nearly all the shapes and sizes a frog can possibly come in. Among this diversity, probably the most famous representatives are the arrow-poison frogs of the Dendrobatidae.Two dendrobatid frogs of two different subfamilies: dyeing dart frog Dendrobates tinctorius (Dendrobatinae, left) and phantasmal poison frog Epipedobates tricolor (Colostethinae, right), copyright H. Krisp. Offhand, has someone been playing silly buggers with dendrobatid species names? Dendrobates auratus is green and black, not gold, and I'm sure I only see two colours on that E. tricolor.The Dendrobatidae are themselves a diverse family, with somewhere in the area of two hundred currently recognised species. Many of these have only recently been recognised: nearly half of the currently known species have been named since 1985 (Grant et al. 2006). There are also ninety or so species in the closely related family Aromobatidae that were historically treated as dendrobatids and still may be in some sources. The Dendrobatidae are currently divided between three subfamilies: about half the species belong to the subfamily Dendrobatinae, a bit less than a quarter to the Colostethinae, and close to sixty species are placed in the genus Hyloxalus that forms its own subfamily (Grant et al. 2006).Panama rocket frog Colostethus panamensis, copyright Brian Gratwicke.Members of the Dendrobatidae are best known, of course, for their remarkable toxicity, associated with bright, striking warning colours. The name 'arrow-poison frog' reflects this trait as an arrow scraped across a frog's skin would pick up some of the frog's own lethality. The toxin, comprising various alkaloids, is not produced directly by the frog itself but is instead acquired through its arthropod diet. Most of the alkaloids sequestered by arrow-poison frogs come from ants (Darst et al. 2005) but other potential sources include beetles, millipedes and oribatid mites. However, not all dendrobatids are toxic and colourful. In fact, these features are largely characteristic of the Dendrobatinae only. Members of the Colostethinae and Hyloxalus are mostly cryptic in coloration and largely do not sequester alkaloids. The distinction is not an unshakeable rule: some non-dendrobatine dendrobatids are quite colourful in their own right and a handful of colostethines (members of the genus Epipedobates) are toxic, having seemingly evolved the ability to secrete alkaloids independently of the dendrobatines. Laboratory studies indicate that at least some non-toxic colostethines are able to consume alkaloid-bearing prey without ill effects, suggesting that alkaloid resistance is ancestral for the family as a whole.Male Hyloxalus nexipus carrying tadpoles, copyright Santiago Ron.More characteristic of dendrobatids as a whole is their breeding behaviour. As a rule, dendrobatids are more or less terrestrial, not habitually living in water, though many species are found alongside the margins of water bodies and may dive into the water to escape danger. Others will be found among leaf litter or be completely arboreal. Eggs are laid in damp terrestrial locations such as under leaves; males may deposit their sperm before or after the female deposits her eggs. Hatching tadpoles are then carried on the back of one of the parents to a suitable body of water such as a pool or stream. In members of the Dendrobatinae, tadpoles are deposited in phytotelmata, water-filled hollows in vegetation (such as in the cenre of bromeliads or holes in trees). Adelphobates castaneoticus, found in Pará in Brazil, has a habit of using the fallen husks of Brazil nuts. In some species, tadpoles are transferred one at a time; in others, groups of tadpoles will be carried en masse. In most genera, the male parent is the primary or sole transporter of tadpoles. Females of some species may also carry tadpoles; in others, a female finding an unattended cache of eggs will simply eat them. In the dendrobatine genus Oophaga, tadpole transport is the sole responsibility of the female. Following deposition, developing tadpoles of many species live on a diet of detritus. Others, particularly among the phytotelm-inhabiting species, are carnivorous, feeding on insects and other aquatic vertebrates, or even on their own siblings. In the aforementioned Oophaga, the transporting female will also lay a deposit of unfertilised eggs at the same time as she drops off the tadpoles. As well as providing food for the developing larvae, these eggs may also carry a shot of alkaloids to provide a head start in developing their defenses.Strawberry poison-dart frogs Oophaga pumilio, two different colour morphs, copyright Pavel Kirillov.Despite their often bright colours, many dendrobatids are poorly known due to cryptic habits and many species are only found in restricted ranges. As well as the usual threats to their survival from habitat destruction and the like, many dendrobatid species are threatened by collection for the pet trade. Their bright colours make dendrobatids popular specimens and captive individuals lose their toxicity if not provided with the prey from which alkaloids are derived. Unfortunately, about a quarter of dendrobatid species are currently recognised as endangered, many severely so. The highest diversity of endangered species is in the northern Andean region, in Venezuela, Colombia and Peru, which is also the centre of diversity for the family as a whole (Guillory et al. 2019). Urgent action may be required if we are to preserve these tiny, shiny, toxic beauties.REFERENCESDarst, C. R., P. A. Menéndez-Guerrero, L. A. Coloma & D. C. Cannatella. 2005. Evolution of dietary specialization and chemical defense in poison frogs (Dendrobatidae): a comparative analysis. American Naturalist 165 (1): 56 69.Grant, T., D. R. Frost, J. P. Caldwell, R. Gagliardo, C. F. B. Haddad, P. J. R. Kok, D. B. Means, B. P. Noonan, W. E. Schargel & W. C. Wheeler. 2006. Phylogenetic systematics of dart-poison frogs and their relatives (Amphibia: Athesphatanura: Dendrobatidae). Bulletin of the American Museum of Natural History 299: 1-262.Guillory, W. X., M. R. Muell, K. Summers & J. L. Brown. 2019. Phylogenomic reconstruction of the Neotropical poison frogs (Dendrobatidae) and their conservation. Diversity 11: 126.Carrots are one of the staple vegetables in this part of the world as well as in a great many others. Indeed, Wikipedia informs us that about forty million tonnes of carrots and turnips were produced worldwide in 2018, and I would have to think that carrots accounted for the greater part of that number. Wild carrots are also a widespread weed that can commonly be seen growing in disturbed, open habitats such as roadside verges. This post is about the group of plants that carrots typify, the subtribe Daucinae.Wild carrot Daucus carota in flower, copyright Cwmhiraeth.Daucinae is a subgroup of the plant family Apiaceae, historically known as the Umbelliferae. The latter name refers to the characteristic production of flowers in dense, flat-topped inflorescences known as umbels. Anyone who is familiar with the appearance of carrot flower-heads is familiar with the form of an umbel; the wild form of carrot is often known as "Queen Anne's lace" in reference to said appearance. The fruit of Apiaceae species is a schizocarp, a dry fruit that splits at maturity into segments (called mericarps), each containing a single seed, that are dispersed independently. In Daucinae and related group of umbellifers, the mericarps carry longitudinal ribs, both primary ribs containing a vascular bundle and secondary ribs without. The secondary ribs of Daucinae are often modified to form broad wings or curved spines that function in the mericarp's dispersal.Broad-leafed sermountain Laserpitium latifolium seedheads, showing wings, copyright Krzysztof Ziarnek, Kenraiz.Historically, these differences in mericarp morphology have been used to assign the species bearing them to different tribes. However, more recent phylogenetic analyses have indicated that changes between wings and spines have occurred on multiple occasions due to changes in mode of dispersal (Wojewódzka et al. 2019). Mericarps bearing wings are generally anemochorous (dispersed by wind) whereas those bearing spines are epizoochorous (carried by animals, such as stuck to a mammal's fur). The distinction is not 100% immutable: winged seeds may sometimes get caught in fur, spined seeds may be carried slightly further by wind than smooth ones. Phylogenies indicate that anemochory was the ancestral condition for Daucinae, retained in genera such as Laserpitium and Thapsia. Epizoochorous species do not form a single clade within the Daucinae (indeed, the genus Daucus includes both anemochorous and epizoochorous species) but it is unclear to what degree epizoochory arose on multiple occasions versus reversions to anemochory from epizoochorous ancestors. Two species of Daucinae, Daucus dellacellae from the Cyrenaica region of northern Africa and Cryptotaenia elegans from the Canary Islands, have neither spines nor wings on their mericarps which are therefore dispersed by gravity alone. In the case of C. elegans, at least, it has been suggested that it evolved from epizoochorous ancestors that lost the spines because of the absence of suitable dispersing animals on the islands (Banasiak et al. 2016).Though the carrot Daucus carota is perhaps the most widely grown daucine umbellifer, it is not the only economically significant member of the group. Cumin Cuminum cyminum, whose seeds are widely used as a spice, is either a daucine or a close relative of daucines (Banasiak et al. 2016). Cuminum does differ from other daucine genera in that its mericarps lack appendages on the secondary keels, however. Gladich Laser trilobum is a perennial found growing in Europe and western Asia whose seeds are used as a condiment. Certain species of the deadly carrot genus Thapsia have a history of medicinal usage though, as their vernacular name suggests, their use does require caution. One species, T. garganica, is among the suggested candidates for the identity of the mysterious silphium of the Romans (used, among other things, as an abortifacient) though perhaps not the most likely contender. That, perhaps, is a story for another time.REFERENCESBanasiak, Ł., A. Wojewódzka, J. Baczyński, J.-P. Reduron, M. Piwczyński, R. Kurzyna-Młynik, R. Gutaker, A. Czarnocka-Ciecura, S. Kosmala-Grzechnik & K. Spalik. 2016. Phylogeny of Apiaceae subtribe Daucinae and the taxonomic delineation of its genera. Taxon 65 (3): 563 585.Wojewódzka, A., J. Baczyński, Ł. Banasiak, S. R. Downie, A. Czarnocka-Ciecura, M. Gierek, K. Frankiewicz & K. Spalik. 2019. Evolutionary shifts in fruit dispersal syndromes in Apiaceae tribe Scandiceae. Plant Systematics and Evolution 305: 401 414.In a previous post, I spoke of the radiolarians, marine protists renowned for their intricate skeletons, and the major radiolarian group known as the Spumellaria. Standing in contrast to the spumellarians is another major group, the Nassellaria. Like spumellarians, nassellarians have a skeleton of silica but whereas the basic shape of spumellarian skeleton is a sphere, that of nassellarians is a cone, bell or some similar shape, arranged along a longitudinal axis. The origination point of the skeleton is at or near the top of the cone and is known as the cephalis (from the Greek for 'head'). There may be an apical spine rising above the cephalis. Below it, the skeleton is commonly divided into recognisable sections referred to as the thorax, abdomen and post-abdominal segments (if present). The nucleus of the cell is more or less associated with the cephalis, contained within it at least during the juvenile stage of development though it may shift below the cephalis as the cell matures (Suzuki et al. 2009).Skeleton of a Eucyrtidium sp., copyright Picturepest.As is commonly the case with unicellular organisms, radiolarian taxonomy has been influenced by disagreements about which features should be regarded as more significant. Some would arrange taxa based on the overal formation of the skeleton. Others would focus on the development of the initial embryonic spicule around which the cephalis develops. A recent phylogenetic analysis of living nassellarians by Sandin et al. (2019), based on both morphological and molecular data, found that overall skeleton morphology was a much better indication of relationships than the internal structure. One well supported subgroup of the Nassellaria is the superfamily Eucyrtidioidea.Eucyrtidioids have a fossil record going back to the Triassic (Afanasieva et al. 2005). The cephalis is spherical and clearly distinguished from the following segments by a constricted basal aperture. The test is usually multi-segmented; members of the subfamily Theocotylinae may have just two segments but other members of Eucyrtidiidae have up to ten segments. Fossil families assigned to Eucyrtidioidea by Afanasieva et al. (2005) may have up to twenty (but as Afanasieva et al.'s concept of Eucyrtidioidea was not found to be monophyletic by Sandin et al., the affinities of these fossil families perhaps warrant re-investigation). Segments are commonly divided by distinct inner rings. The skeleton lacks feet, the term used for protruding spines around the basal aperture of the skeleton found in many other nassellarians.The phylogeny of nassellarians indicated by Sandin et al. (2019) places the Eucyrtidiidae as the sister taxon to other living nassellarians. Other living families included in the Eucyrtidioidea by Afanasieva et al. (2005) were placed in more nested positions. The implication is that the multi-segmented condition may be ancestral for crown Nassellaria. Segments are added progressively during the life of the radiolarian, leading the organism to look quite different at different ages. Indeed, this metamorphosis is pronounced enough that one of the earliest influential researchers on radiolarians, Ernst Haeckel (he of Kunstformen der Natur fame), made the mistake of classifying different ages as different species, genera and even families. Our understanding may be better than in Haeckel's time but there may still be a lot to learn about these intricate organisms.REFERENCESAfanasieva, M. S., E. O. Amon, Y. V. Agarkov & D. S. Boltovskoy. 2005. Radiolarians in the geological record. Paleontological Journal 39 (Suppl. 3): S135 S392.Sandin, M. M., L. Pillet, T. Biard, C. Poirier, E. Bigeard, S. Romac, N. Suzuki & F. Not. 2019. Time calibrated morpho-molecular classification of Nassellaria (Radiolaria). Protist 170: 187 208.Suzuki, N., K. Ogane, Y. Aita, M. Kato, S. Sakai, T. Kurihara, A. Matsuoka, S. Ohtsuka, A. Go, K. Nakaguchi, S. Yamaguchi, T. Takahashi & A. Tuji. 2009. Distribution patterns of the radiolarian nuclei and symbionts using DAPI-fluorescence. Bulletin of the National Museum of Nature and Science, Series B 35 (4): 169 182.Tricolia pullus, copyright Ar rouz.Search among patches of seaweed along the shores of Africa, Australia or warmer parts of Eurasia and you may be able to find represents of the marine gastropod genus Tricolia. Tricolia are small shells, less than a centimetre in height, with shiny shells that may be smooth or spirally ribbed. Most species have a moderately high spire and an ovate shape but some are lower and more globose (Knight et al. 1960). The shell may or may not have an umbilicus, and there is a calcareous, externally convex operculum. Tricolia belongs to the Phasianellidae, commonly known as pheasant shells, presumably in reference to the bold, intricate colour patterns of many species. Species of Tricolia and the closely related genus Eulithidium, which replaces it in the Americas, have shell pigments containing porphyrin that fluoresce under ultraviolet light (Vafiadis & Burn 2020). Over forty species of Tricolia are currently recognised with the highest diversity in southern Africa (Nangammbi et al. 2016). However, the taxonomy of the genus has historically been confused due to polymorphic species being named multiple times; it is possible that at least some of the apparent African diversity is an artefact of the genus being largely unrevised in that region. An analysis of some of the southern African taxa by Nangammbi et al. (2016) found that some 'species' could not be distinguished genetically. They were, nevertheless, distinct geographically and the authors suggested that they may be variants of a single species responding to different environments.Variants of Tricolia kochii, copyright Brian du Preez.Like other members of the Vetigastropoda (the clade containing most of what used to be called the 'archaeogastropods'), Tricolia species have a simple life cycle without an actively feeding planktonic larva. The basic mode of reproduction is by broadcast spawning with separate males and females releasing gametes into the water column. After fertilisation, a brief non-feeding planktonic phase is nourished by yolk from the egg before the larva settles. The brevity of this phase is reflected by the resultant form of the protoconch which accounts for less than an entire whorl. In the Indo-West Pacific species T. variabilis, the male is smaller than the female and sits directly on her, waiting to fertilise her eggs as they are laid as gelatinous capsules rather than freely broadcasted. A temperate Australian species, T. rosea, takes things a step further as the female broods embryos (up to nearly fifty at a time) within the cavity of the last shell whorl (Vafiadis & Burn 2020). How the eggs are actually fertilised remains unknown but all embryos within a brood are about the samesize and stage of development, indicating a single fertilisation event; perhaps males associate with females as in T. variabilis. After the young pheasant shells hatch or settle, they initially feed on diatoms and other microalgae until they eventually grow enough to move onto the seaweed fronds that will comprise their adult diet.REFERENCESKnight, J. B., L. R. Cox, A. M. Keen, R. L. Batten, E. L. Yochelson & R. Robertson. 1960. Gastropoda: systematic descriptions. In: R. C. Moore (ed.) Treatise on Invertebrate Paleontology pt I. Mollusca 1. Mollusca general features, Scaphopoda, Amphineura, Monoplacophora, Gastropoda general features, Archaeogastropoda and some (mainly Paleozoic) Caenogastropoda and Opisthobranchia pp. I171 I351. Geological Society of America: Boulder (Colorado), and University of Kansas Press: Lawrence (Kansas).Nangammbi, T. C., D. G. Herbert & P. R. Teske. 2016. Molecular insights into species recognition within southern Africa's endemic Tricolia radiation (Vetigastropoda: Phasianellidae). Journal of Molluscan Studies 82: 97 103.Vafiadis, P., & R. Burn. 2020. Internal embryonic brooding and development in the southern Australian micro-snail Tricolia rosea (Angas, 1867) (Vetigastropoda: Phasianellidae: Tricoliinae). Molluscan Research 40 (1): 60 76.The digger wasps of the tribe Crabronini are a widespread group distinguished by a boxy head shape and relatively stout mesosoma. They are not dissimilar to hairless bees and indeed are close relatives of that group. There is a wide diversity of crabronins around the world; among their representatives here in Australia are members of the genus Podagritus.Podagritus cf. tricolor, from Insects of Australia.Podagritus species are medium-sized, elongate crabronins, generally in the region of a centimetre in length (give or take a few millimetres). The gaster is pedunculate (that is, the first segment of the metasoma is drawn into an elongate peduncle). Other, finer features distinguishing them from related genera of crabronins include a palpal formula of 5-3 (referring to the number of segments in the maxillary and labial palps, respectively; 5-3 indicates that both palps are slightly reduced from the ancestral count for crabronins) and often the presence of a sharp subvertical ridge, the omaulus, near the front of the mesopleuron (the median plate on the side of the mesosoma). If the omaulus is not present as such, there is still a distinct curve where it would have been so the planes of the mesopleuron on either side are more or less perpendicular. Females have a well defined triangular, flat pygidial plate and males often have one as well (Bohart & Menke 1976).Thirty species of Podagritus were recognised from Australia by Leclercq (1998). Other species of the genus are known from New Zealand and South America. Historically, the Australian species have been treated as a distinct subgenus Echuca from Podagritus elsewhere, based on features such as a well defined, flat prepectus and a weakly sculpted metapleuron. Leclercq, however, questioned the value of this distinction, noting the existence of a couple of Australian species sharing notable features in common with species found elsewhere, and suggested abandoning subgenera until the genus could be revised as a whole.The natural history of Podagritus species in Australia remains poorly known. One species found in the east of the continent, P. leptospermi, has been found nesting in a sloping gravel bank (Bohart & Menke 1976). Burrows were near vertical and close to a foot deep, and contained two or three cells placed at the ends of lateral galleries (one cell per gallery). Entrances were surrounded by flat mounds of sand six to ten centimetres wide and were not closed while the female was out hunting. Cells were stocked with flies (Tachinidae and Therevidae, so presumably reasonably large) that were initially stored at the bottom of the burrow before being placed in the cell head inwards and belly up, in lots of four to six. The egg was attached to a fly between the head and thorax, so when the larva hatched it would find itself already in place on a welcoming bed of food.REFERENCESBohart, R. M., & A. S. Menke. 1976. Sphecid Wasps of the World. University of California Press: Berkeley.Leclercq, J. 1998. Hyménoptères sphécides crabroniens d'Australie du genre Podagritus Spinola, 1851 (Hymenoptera, Sphecidae). Entomofauna 19 (18): 285 308.Diving beetles of the family Dytiscidae are a distinctive component of the freshwater environment in most regions of the world. They have an oval, streamlined body form and powerful hind legs, usually with fringes of stiff setae, that are ill-suited for movement on land but make them adept swimmers. They are also almost always capable fliers, allowing them to find their way to water bodies of any size from large lakes to small, temporary pools. Both adults and larvae are active hunters, preying on other aquatic arthropods or even small vertebrates. Most diving beetles are fairly dull in coloration but exceptions are found among members of the tribe Aciliini.Sunburst diving beetle Thermonectus marmoratus, from Insectarium de Montréal, René Limoges.Members of the Aciliini are moderately sized diving beetles, generally between one or two centimetres in length. Dorsally they have a yellow to red base coloration with contrasting dark markings. The hind legs are robust with the hind tibia short and broad. Males have the base of the tarsus of the front legs broadened into a round palette with setae on the underside modified into sucking discs, used to hang onto the females when mating; this discs may be present on the tarsus of the mid pair of legs as well. They are strong swimmers, often venturing into the open waters of lakes and pools, and contrast with other diving beetles in that they may be found in pools lacking submerged vegetation (Roughley & Larson 2001; Bergsten & Miller 2006). Larvae have a distinctive arched body shape with a small head (Bukontaite et al. 2014), kind of shrimp-like, and also tend to be more pelagic than the larvae of other diving beetles. Females have gonocoxae (the appendages at the end of the abdomen that function as the ovipositor) that are relatively long with a broadened, spoon-like ending (Miller 2001); these are used to insert eggs into damp moss or under loose bark of vegetation lying just above the waterline. There is usually just one generation per year and adults in cold regions overwinter in larger water bodies that remain unfrozen.Alternate morphs of female Graphoderus zonatus with granular (left) and smooth elytra, from Holmgren et al. (2016).Perhaps the most intriguing aspect of aciliin diving beetles regards their sexual dimorphism. As noted above, males have a set of suckers on the fore legs for hanging onto females when mating. However, females of some species have sculpted elytra rather than the smooth elytra of males, such as a granular surface in Graphoderus species or long, setose sulci in female Acilius. The uneven surface produced by these features presumably functions to reduce the efficacy of the males' suckers, allowing the females more control when selecting a mate. That such a conflict exists is supported by the observation that the more developed the males' sucker arrays in a population, the more likely the females are to have repellent sculpturing. Males of some diving beetle species have been observed grabbing at any female they encounter, followed by the female swimming rapidly and erratically in an attempt to shake the male off or knock him off against the substrate or objects in the water (Miller 2003). Where this becomes really interesting is that some species have dimorphic females with some females in the population having sculpted elytra whereas others are smooth. What could be the reason for such variation? The presence of both forms in the population suggests that neither has a complete advantage over the other. It may be that smooth-backed females trade reduced defenses for improved swimming ability. Alternatively, a defensive female may be able to ensure that only the strongest and most resilient males can mate with her, but runs the risk of not mating at all if she never encounters a male who can overcome her defenses. A less defensive female may be more vulnerable to any male she encounters but at least she's bound to be fertilised at some point.REFERENCESBergsten, J., & K. B. Miller. 2006. Taxonomic revision of the Holarctic diving beetle genus Acilius Leach (Coleoptera: Dytiscidae). Systematic Entomology 31: 145 197.Bukontaite, R., K. B. Miller & J. Bergsten. 2014. The utility of CAD in recovering Gondwanan vicariance events and the evolutionary history of Aciliini (Coleoptera: Dytiscidae). BMC Evolutionary Biology 14: 5.Holmgren, S., R. Angus, F. Jia, Z. Chen & J. Bergsten. 2016. Resolving the taxonomic conundrum in Graphoderus of the east Palearctic with a key to all species (Coleoptera, Dytiscidae). ZooKeys 574: 113 142.Miller, K. B. 2003. The phylogeny of diving beetles (Coleoptera: Dytiscidae) and the evolution of sexual conflict. Biological Journal of the Linnean Society 79: 359 388.Roughley, R. E., & D. J. Larson. 2001. Dytiscidae Leach, 1815. In: Arnett, R. H., Jr & M. C. Thomas (eds) American Beetles vol. 1. Archostemata, Myxophaga, Adephaga, Polyphaga: Staphyliniformia pp. 156 186. CRC Press: Boca Raton.I'm an entomologist and taxonomist, currently based in Perth, Western Australia. 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One rather sad ...*Ctenomorpha gargantua* Brock Hasenpusch, the Gargantuan Stick-Insect, is no doubt one of the world s longest insects. Females measure more than 50 cm...Meridian Hill Park is one of the subunits of Rock Creek Park, in Washington, D.C., having joined it in 1910. It is a roughly rectangular parcel bounded o...Michael Denton is a New Zealand biochemist, a Senior Fellow at the Discovery Institute, and the author of two Intelligent Design Creationist books: *Evol...There are a large number of companies out there selling a large number of different scanners employing all kinds of methods for 3D scanning. LIDAR scanners...I am excited to announce the return of the Holiday Insect Print Sale, now in its 9th year! I have selected 35-ish photographs that will be available at 70%...While there is an oft-mentioned quote by evolutionary biologist JBS Haldane that God has an "Inordinate Fondness For Beetles", it is becoming apparent that...Tweedy's pussypaws has long challenged plant taxonomists. Should they abandon Darwinian evolution for an alternative? Photo by Hike395.Tweedy's pussypaw...With the COVID-19 pandemic, many of us are working at home, instead of in the field. In spite of this, I think that I have made a taxonomic discovery that ...It's funny how some images stick in the mind. A few years ago Chris Freeland (@chrisfreeland), then working for Biodiversity Heritage Library (BHL), crea...Four years ago I met with the designers for the new gallery spaces for the large redevelopment project for Plymouth City Museum and Art Gallery (rebranded ...If you hunt around the right bits of various websites, you can still find adverts for a book called The Pterosauria that doesn t exist. Conceived as a pt...The only diagram in the Origin is famously the hypothetical series of species forming a tree structure, but it isn t an actual classification based on his Dear me, it s been awhile, hasn t it? My tardiness in keeping this blog going has not bee...Our special guest post this week comes from Dr. Liz Clark of Yale University in New Haven, Connecticut, USA. She continues to bring biomechanics-fu to echi...Subject: Young Mantids Geographic location of the bug: Campbell, Ohio Date: 08/02/2020 Time: 6:05 PM EDT Last November, while in Ohio, Daniel cleared s...Having just completed one book manuscript, with another one due at the end of this year, I don t have time for the angst and depression that grips me curre...Whenever it was that our city joined the polychromatic bin revolution, we were given a choice of 4 different green (kitchen waste and garden trimmings) b...by Richard Conniff/Yale Environment 360 On the perpetual campaign trail, Donald Trump likes to brag that his regulatory rollbacks will save Americans from ...The deep sea, areas of the ocean below 200 meters, is the largest biome on Earth vast, remote, and inhospitable. These conditions create unique challenges...This week saw the release of a new paper that has implications for dinosaur metabolism. Dawson, R.R., Field, D.J., Hull, P.M., Zelenitsky, D.K., Therrien, ...January 20th is Penguin Awareness Day (one of two annual penguin themed holidays, the other being World Penguin Day on April 25th). To celebrate, why not t...So. I'm coming back after a long hiatus because this paper dropped not long ago and I've got feelings. Here's the press release.A quick summary: Sarah Mei...Beetles are often pretty good botanists, and when it comes beetle botanists there are none finer than species in the family Chrysomelidae. Members of this ...London, UK. Remarkably, a UK university with student approval ratings lower than the Mariana trench has announced plans to improve the student experience ...*Wang, W., Li, C., Scheyer, T. M., and Zhao, L. 2019. A new species of Cyamodus (Placodontia, Sauropterygia) from the early Late Triassic of south-west C...https://ars.els-cdn.com/content/image/1-s2.0-S1342937X16300041-gr6_lrg.jpg]Strict consensus tree from three most parsimonious trees of Bai *et al....Humans have been exercising selection in dogs since the domestication of the wolf. In the first instance we found a natural and quite gradual selection in ...A kingsnake eating a rattlesnakeKingsnakes get their name because they eat other snakes, including venomous snakes like copperheads, cottonmouths, and rat...I wrote about Point Impossible, near Torquay on Victoria's coast several years ago, but I was back there again today looking for more sand dune vegetation....Photo by Karen OsbornSo, Every July 1st is the, now posthumous, birthday of NMNH curator Kristian Fauchald, who was one of the most prolific taxonomists p...Before human settlement, the forests of New Zealand were full of Kakapos, meaning night parrot in the Maori language. These bizarre birds are unlike......It has been over a year since I last posted. I m still trying to figure out what to do with the blog going into the future. In the meantime, I visited Texa...Territorial male Common DarterOne of the commonest dragonflies in the UK, especially in the south, is the Common Darter *Sympetrum striolatum*. One of at ...Ants really like sugar. This fact is obvious to anyone who has encountered a discarded lollipop on a summer sidewalk. Of course, this sweet tooth makes sen...I am so very behind on getting data from the Dragonfly Swarm Project shared here, but I wanted to get the data from this year so far up! Here s what I ve ...Some general reading on mites of possible educational interest. The story can be freely used for educational purposes if properly referenced to the author ...Lately I ve been thinking a lot about the future. It s partly that the Peabody is engaged in a large-scale planning exercise that, when implemented, will c...Earlier today I reflected on my start as a Blogger over on Twitter, which is basically where I blog now (hashtag blogging is dead or something). Stephen H...Very little is known about the lifespan and reproductive biology of the ocean sunfish, Mola mola, after which this blog is named. They can live to be at le...I m pleased to announce that I have been appointed as the Dean of Students at McGill! This appointment will start on 1 August, and will certainly involve a...A few posts ago I presented a puzzle what were the strange arthropod-like creatures I found in a KOH-dissolved slurry of eastern gray squirrel skin? I ca...Today I step away from something that has occupied my life for over two decades now. I have no idea if I will ever return. It saved my life when I needed...Greetings to you all So you may be thinking that myself and Chris have died or forgotten about this little spot in the giant ocean that is the internet. We...Habrocerus capillaricornis for some reason waggles it s abdomen up and down quite frequently. I have absolutely no idea why, but they do and it s absolutel...*Xenoturbella*, Acoela, and Nemertodermatida are worm-like simple bilateral animals, which might give insights into the earliest steps in the evolution of ...*A scene from one of my favorite movies, The Goonies - with Haystack Rock (a Neogene igneous intrusion) and Cannon Beach in the background, and typical ...Cane toads are toxic because their bodies are loaded with cardiac glycosides, deadly toxins that can stop a predator s heart. Because the toads are non-nat...*Hibiscus rosa-sinensis* 'Boreas Yellow' in a bed of basil.Summer is rapidly approaching in the Austral Home Bug Garden and I've been distracted by all of...Last week I wrote about mites that live alongside honey bees, eating and reproducing within their hives. There are many tiny animals that associate with so...As readers might detect, I have a soft spot for highly derived taxa of obscure origins that appear to be perched atop long branches. Tarsiers, pangolins, E...Giant clams typically present viewers with a prominent gape, which is enhanced in living animals by a colourful and fleshy mantle filled with photosyntheti...Little has changed since I last touched upon Meganthropus in 2007. Google results are still dominated by Internet-kitsch connecting the name to fallen an...There arose a need for a new tree for a parasitology meeting, so after almost five years, I finally updated the tree of eukaryotes. There are still things ...I put out a call on Twitter for volunteers to go out looking for winter millipedes for me, and people responded! Totally cool! So this post will serve as a...Okay, everybody knows how plants can cope with adverse conditions, especially when it comes to dormant organs just waiting to resprout when spring or whate...This has been coming for a while, but I needed a push to make it official. I m not much of a blogger anymore (four posts a year doesn t quite cut it), so i...You can apply at the "Careers" section of the Masrani website, but I suggest you take a look around while you're there, too. I just got accepted!Hold on...A guest post by Jen Guyton In my lap was a specter, one of the most elusive animals in sub-Saharan Africa. I d been waiting years to see it, and now it was...Shaw s *Lophius monopterygius* from *The Naturalist s Miscellany*. After initially classifying it as an anglerfish, Shaw had doubts and wondered if it ...As of right about today, I m moving both Denim and Tweed and my professional site to a new domain: jbyoder.org. I ve imported the complete D T archive to i...After over 7 years here on the excellent Blogger platform, The Flying Trilobite has moved!Come visit me at the new glendonmellow.com! If that link ha...Many thanks to Dave Hone for posting the great photos from Steve Cohen of the new AMNH Exhibit. I have been meaning to post about the exhibit over a month ...No, not an April Fool s joke. From today, the Raffles Museum officially becomes Lee Kong Chian Natural History Museum. Since our public gallery closed a ye...The Mesozoic (the so-called 'age of dinosaurs') is not only famous for the terrestrial dinosaurs but a host of large to gigantic reptiles living full time ...Wow, it's been a long time since I wrote something here. Let's see if I can remember how this goes: I find a weird-looking bug and take some photos. Then...The name of this blog will live on as a tumblr consisting of all sorts of odds and ends and kinda-copyrighted things (hooray for havens), but it is time to...I am now writing at The Lord Geekington (WordPress) and Biological Marginalia (tumblr). I really need to stop doing this.I don't know if anybody out there is still following, but I am now writing at The Lord Geekington (WordPress) and Biological Marginalia (tumblr). Some of t...Bell et al. report on a new Edmontosaurus fossil with soft-tissue impressions around the skull and neck, including a structure they interpret as a cockscom...I would tell you more about this specimen but Animal Collective thinks it might be grammy material so I have to exercise discretion.I ve had a lot of life changes since my last activity her. I ve gotten married, defended my PhD, and moved to Lund, Sweden to do my postdoctoral research w...Giant Fanged Death Maggots that Spit Glowing Green Snot, plus epically bad 1970s couture.The 15th meeting of the Mid-Atlantic Malacologists took place yesterday at the Delaware Museum of Natural History (DMNH) in Wilmington, Delaware. I counted...In August, 2012 I guided a five-day abridged version of my Absolute Birding tour. It was with Ron and Ben Barkley, a farther son duo from the U.S.A. Ben is...This post is mostly a note to myself so that I remember how to do this next time I upgrade or reinstall my system. But, perhaps it will be of use to others...Dusting off the old blog to help out a good cause. Below is a message from the good folks at Pipestone Creek Dinosaur Initiative (PCDI). They have started ...The "First human ancestor", which the ABC reports looked "like a squirrel" is of course not to be mixed up with the "Human Family's Earliest ancestor", nam...This year, the *Hennig meeting* was held at *Riverside*, California, and I'm fortunate enough to be able to be there (in great part thanks to the *Kurt Pic...So I'm still not dead. But I am posting far less often, as you can probably notice. The good news first, though: I am "stable" in terms of health. I'm stil...Tropical fish keeping as a hobby can be a wonderful way to appreciate the fascinating creatures that live beneath the waves. But we want to see hobbyists...What a remarkable 150th birthday year it s been for Archaeopteryx! Sesquicentennial celebrations, commemorative coins and stamps, historical articles, and ...[image: i-123d9fb0d5588d4fef6a86f590077043-Tet-Zoo-ver-3-banner-200-px-135-px-Oct-2011.jpg]You are currently at the old, defu...Trying to keep both this and my new sciam blog going has been a bit of a strain. I've decided therefore that from now on all my science writing will be hos...After a few weeks of denial, I ve decided that I need to announce a blog vacation. I ve just started graduate school and need a bit of time to get settled ...Wednesday was the final day of the IBCM California workshop. The weather forecast had been marginal, however we woke to a gloriously sunny day as we heade...What a month for publications it has been, it seems that all the fruits of my major paper-writing push last year, which incidentally explains the quiescenc...My first day of retirement , I took the Trifecta to school, ran some errands and then wanted to get out. It was a cold, windy day, with intermittent sno...The word gull probably has the ability to elicit the widest range of emotion among birders and non-birders alike of any bird name. To some birders, gull...There are still quite a few people who have not updated their RSS feeds for Arthropoda s new RSS address. Get with the program, slackers!There s no getting around it, science is a social enterprise. Go ahead, try and do some by your lonesome. Oh, you may putter and dial-twirl and churn out s...This week, I was graciously invited to join the Southern Fried Science blog network. I accepted, and so will be relocating to www.cephalove.southernfrieds...Please update your bookmarks and feeds. This blog has moved to http://myrmecos.net/ . The new RSS feed is: http://myrmecos.net/feed/ If that URL looks fami...Tour de France time! Amazed it has come around again already doesn t seem like a year since all those late nights watching the cycling on SBS. Anyway, ins...I thought of these a couple of years ago and haven't gotten around to publicly deploying them. I decided I'd better tell someone so that if I'm killed in o...No one at Duke seems to know what this is. Southern Fried Scientist has allowed me to copy verbatim his post in the hopes that maybe someone out there in T...The email (from a reliable source) advises that the photo was recently taken during a fly......is not meant to be a blog, but a gallery of mosses and liverworts. The pictures are meant to be helpful for species identification both in the field and...Yes, that s a bonnethead shark (Sphyrna tiburo) and yes, that s the Detroit River. The photo was taken on July 21, 2006, by area resident Richard Kik IV ...Just in time for the holidays, I m happy to announce the grand opening of Cthulhu s Bar Grill! It s a one-stop shop for vaguely Cthulhu-related t-shirts a...Finally back for some discussion of saber-tooth cats, nimravids, and barbourofelids. There are two complementary articles that appeared almost simultaneous...When discussing the macroevolution of scorpions, little of interest can be discussed about the tail! However, in lower level classification, keels...

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