Field of Science

Platybunus: the Wide-Eyed Harvestmen of Europe

The western Palaearctic region (that is, Europe and the immediately adjacent parts of Asia and northern Africa) is home to a diverse and distinctive fauna of harvestmen. Among the various genera unique to this part of the world are the forest- and mountain-dwellers of the genus Platybunus.

Platybunus pinetorum, copyright Donald Hobern.


Platybunus species are moderate-sized long-legged harvestmen of the family Phalangiidae, the central body in larger individuals being about eight millimetres long (Martens 1978). Their most characteristic feature is a relatively large eye-mound, distinctly wider than long and occupying a large section of the anterior carapace. As with other European phalangiids, they eye-mound is ornamented with a row of denticles each side though the body lacks denticles over the remainder of the dorsum. The body is often comparatively slender, tapering towards the rear (particularly in males), and is marked on the dorsum by a darker median band. The pedipalps have a pair of well-developed setose apophyses on the inner distal ends of the patella and tibia, and a series of long spine-like tubercles on the underside of the femur. These tubercles presumably function in the capture of prey, forming a basket that can be closed around the harvestman's victims. External sexual dimorphism in Platybunus is fairly minimal though females are overall larger and fatter. The penis is notably long and slender with a relatively small glans, offset from the shaft by a more or less marked constriction.

Platybunus bucephalus, copyright Adrian Tync.


Martens (1978) recognises four species of Platybunus found in higher altitude regions of central Europe with the species P. bucephalus and P. pinetorum occupying much of the genus' range. Platybunus bucephalus may be distinguished from P. pinetorum by, among other features, its relatively shorter legs. Platybunus pallidus is endemic to the Carpathians, and the tiny P. alpinorelictus inhabits the Garda Mountains of northern Italy. Another species, P. anatolicus, was described from Turkey by Roewer (1956)*. In general, Platybunus species inhabit alpine and subalpine forests, being found among the herbaceous undergrowth, under bark or on rock faces. Where their ranges overlap, P. bucephalus is more accustomed to extending beyond the forest margins than P. pinetorum and may be found above the tree-line. In recent years, the range of P. pinetorum has extended northwards, being first recorded from the UK in 2010 and Sweden in 2015 (Fritzén et al. 2015). At least some populations of P. pinetorum are capable of reproducing parthenogenetically and this may have played a part in its spread.

*Platybunus mirus was described by Loman (1892) on the basis of two male specimens that supposedly came from Sumatra. Though the identity of this species has never been resolved (Loman's illustration of the penis is at least suggestive of a true Platybunus), the claimed locality seems almost certain to be an error of some kind.

The internal classification of the Phalangiidae remains in need of further investigation. Platybunus has been recognised by some authors as forming a subfamily Platybuninae with a cluster of other western Palaearctic genera bearing similar ventrally spined pedipalps (Zhang & Zhang 2012). However, other authors have not separated this group from the subfamily Phalangiinae. The platybunines may represent a phylogenetically coherent grouping, or their shared features may reflect adaptations to a similar life style. The genital morphology of Platybunus is recognisably distinct from that of other platybunines which may argue against any relationship (Martens 1978). On the other hand, platybunines might possibly be distinguished from phalangiines by the chemical composition of their repugnatorial gland secretions (Raspotnig et al. 2015). A formal analysis of the family's evolution would be a welcome advance.

REFERENCES

Fritzén, N. R., V. Rinne, M. Sunhede, A. Uddström, S. Van de Poel & P. De Smedt. 2015. Platybunus pinetorum (Arachnida, Opiliones) new to Sweden. Memoranda Soc. Fauna Flora Fennica 91: 37–40.

Loman, J. C. C. 1892. Opilioniden von Sumatra, Java und Flores. In: M. Weber (ed.) Zoologische Ergebnisse einer Reise in Niederländisch Ost-Indien vol. 3 pp. 1–26, pl. 1. E. J. Brill: Leiden.

Martens, J. 1978. Spinnentiere, Arachnida: Weberknechte, Opiliones. Gustav Fischer Verlag: Jena.

Raspotnig, G., M. Schaider, P. Föttinger, V. Leutgeb & C. Komposch. 2015. Benzoquinones from scent glands of phalangiid harvestmen (Arachnida, Opiliones, Eupnoi): a lesson from Rilaena triangularis. Chemoecology 25: 63–72.

Roewer, C. F. 1956. Über Phalangiinae (Phalangiidae, Opiliones Palpatores). (Weitere Weberknechte XIX). Senckenbergiana Biologica 37 (3–4): 247–318.

Zhang, C., & F. Zhang. 2012. On the subfamilial assignment of Platybunoides (Opiliones: Eupnoi: Phalangiidae), with the description of a new species from China. Zootaxa 3190: 47–55.

Voley, Voley, Voley

Over a third of all living mammal species are rodents. In cooler regions of the Northern Hemisphere, the rodent fauna is often dominated by the Microtinae, the group of mouse-like rodents including voles and lemmings. And in North America, the most widespread of all microtine species is the eastern meadow vole Microtus pennsylvanicus.

Eastern meadow vole Microtus pennsylvanicus, copyright Gilles Gonthier.


The eastern meadow vole is found over most of Canada and a large part of the northern and eastern United States, with the subspecies M. p. chihuahuensis known from Chihuahua in northern Mexico. This species is about the size of a small rat, being from 14 to 20 cm in length with about three to six centimentres of that length being tail (Reich 1981). They are generally yellowish-brown in colour with black tips on the hairs though individuals vary significantly in brightness and shade. Western populations are supposed to be lighter in coloration than eastern, and southern individuals tend to be larger than northern. As an indication of this species' variability, Reich (1981) recognised 28 recognised subspecies.

Eastern meadow voles are primarily inhabitants of grasslands, with a preference for damper habitats, though they may also be found in woodlands. They mostly live in burrows underground, emerging to the surface to forage for food. Eastern meadow voles are generalist feeders, browsing on most available forms of low vegetation: grasses, sedges and herbs. When populations reach their peak, they may cause significant damage to woody plants by ringbarking their trunks. Individuals may seemingly be active at just about any time of day.

Eastern meadow vole in a state of danger, copyright David Allen.


Like other small rodents, meadow voles are short-lived animals with estimates of average lifespan ranging from just two or three months to ten to fourteen months (Reich 1981). Studies of movement patterns indicate that mature females generally maintain distinct, non-overlapping ranges whereas males range further and with less concern for others (Madison 1980). Mating behaviour appears generally promiscuous: males will range over the territories of multiple females and litters with mixed paternity are not uncommon (Boonstra et al. 1993). Paternal behaviour has been observed among eastern meadow voles in laboratory populations but all indications are that wild males do not remain with females after mating. Males often bear wounds indicative of intra-species conflict. These may be the result of males fighting over access to females but Madison (1980) suggested a potential alternative. Less dominant males might be more likely to attempt to approach females earlier or later in their oestrus cycle as the females are more likely to be guarded by dominant males when at their peak. While avoiding attacks from their dominant brethren, these minor males might find themselves violently rebuffed by a female who is just not yet in the mood.

After mating, gestation lasts for about three weeks, usually resulting in a litter of four to six babies. Weaning then takes place after about two weeks. Females forage far less while lactating than at other times. It might seem counter-intuitive for a female to reduce feeding when her energy demands are presumably at their peak but again Madison (1980) suggests an explanation: perhaps her energy needs are such that she simply lacks the capacity for extensive wandering. Young may potentially remain with their mother for some time after weaning but eventually they will be forced out of the parental burrow, leaving to face the wide world on their own. And when you're the size of a vole, that's a very wide world indeed.

REFERENCES

Boonstra, R., X. Xia & L. Pavone. 1993. Mating system of the meadow vole, Microtus pennsylvanicus. Behavioral Ecology 4: 83–89.

Madison, D. M. 1980. Space use and social structure in meadow voles, Microtus pennsylvanicus. Behavioral Ecology and Sociobiology 7: 65–71.

Reich, L. M. 1981. Microtus pennsylvanicus. Mammalian Species 159: 1–8.

Anchor Sponges

Sponges are, by their very nature, a challenging group taxonomically. At the macroscopic level, they are often amorphous and indeterminate in appearance. As one taxonomist complained in 1842 (as quoted in Hooper & Van Soest 2002): "there is so much that is in common to them, and each adapts itself so readily to circumstances and assumes a new mask, that it requires a tact, to be gained only by some experience, to recognize them under their guises; while we labour, perhaps in vain, to devise phrases which shall aptly portray to others the characteristics of objects that have no fixed shape, and whose distinctive peculiarities almost cheat the eye". Reliable identification typically requires the close examination of microscopic details, in particular the conformation and arrangement of the mineralised spicules that make up the skeleton of many sponges.

Myxilla incrustans, copyright B. E. Picton.


The Myxillidae are a family of marine sponges that, so far as we currently know, are most diverse in temperate and frigid waters. Like other members of the class Demospongiae, the most diverse of the recognised sponge classes, they have a skeleton of spicules constructed from silica. Different arrangements of spicules allow the body of the sponge to be divided into two layers. In the outer ectosoma, which can be thought of as the 'skin' of the sponge, elongate spicules are vertically radiating or placed in 'bouquet' arrangements with a palisade of vertical spicules surmounted by radiating clusters. These spicules generally have each end similar and may be smooth or spiky. In the inner choanosoma, within which are placed the feeding chambers of the sponge, elongate spicules are placed in a reticulate arrangement. These spicules generally have one end pointed and the other blunt.

Skeletal arrangements and individual spicules from various Myxillidae, from Hooper & Van Soest (2002).


Mixed in amongst these larger megasclere spicules are smaller microscleres that do not form part of the main structural skeleton, though presumably they do help hold the sponge body together. In myxillids, the microscleres generally take the form of anchorate chelae, small curved structures with incurved rounded prongs at each end. Members of the boreal genus Melonanchora have a mixture of chelae and a different type of microsclere shaped like a ribbed rugby ball (Santín et al. 2021). In the Indo-West Pacific genus Psammochela, growing sponges will also incorporate sand from the surrounding environment to supplement the microscleres (de Voogd 2012).

Growth habit of Myxillidae can vary from encrusting to massive to branching. The species Stelodoryx procera, found around the Azores, has a distinctive growth habit with a flattened main body at the end of an elongate stalk. On the whole, though individual species may be distinguished by growth habit, species within a single genus may differ greatly in form. For determining genera, examination of spicules is really the only way to go.

REFERENCES

Hooper, J. N. A., & R. W. M. Van Soest. 2002. Systema Porifera: A guide to the classification of sponges vol. 1. Kluwer Academic/Plenum Publishers.

Santín, A., M.-J. Uriz, J. Cristobo, J. R. Xavier & P. Ríos. 2021. Unique spicules may confound species differentiation: taxonomy and biogeography of Melonanchora Carter, 1874 and two new related genera (Myxillidae: Poecilosclerida) from the Okhotsk Sea. PeerJ 9: e12515.

Voogd, N. J. de. 2012. On sand-bearing myxillid sponges, with a description of Psammochela tutiae sp. nov. (Poecilosclerida, Myxillina) from the northern Moluccas, Indonesia. Zootaxa 3155: 21–28.

Succulent Orchids

With over 1200 known species found in Asia and Australasia, Dendrobium is one of the largest currently recognised genera of orchids. As with other examples of such 'super-genera', the question of how to best handle such a monster has been fiercely debated. In 2003, Australian botanist M. Clements proposed dividing Dendrobium between numerous segregate genera, noting (among other reasons) that the genus as previously recognised was not monophyletic. However, Clements' system does not seem to have garnered widespread usage with other orchid systematists preferring to retain a broad concept of Dendrobium (excluding some of the more egregious outliers) that largely corresponds with its established usage (e.g. Schuiteman 2011). Nevertheless, many of the subdivisions promoted by Clements remain recognised as well delimited groups. One such cluster is the assemblage of species recognised as Dendrobium section Aporum.

Growth habit of Dendrobium sect. Aporum, copyright Tony Rodd.


Species of section Aporum are epiphytes found in lowland forests of south-east Asia, extending eastwards to New Guinea and the Solomon Islands. Members of this section have thin stems that are erect at first but tend to become pendulous as they lengthen. Leaves are fleshy and equitant: that is, they are folded longitudinally with what would otherwise be the two sides of the dorsal surface fused, except at the base where they overlap with opposing leaves. The stem may be more or less completely concealed by the leaf bases. Tips of the leaves end in a point. Flowers are borne singly or in clusters, arising laterally on the stem between leaf nodes or at the tip of the stem alongside a terminal scale. The flowers may be subtended by persistent chaffy bracts. They are generally small and fleshy and tend to be short-lived, wilting after just a few days.

Flowers of Dendrobium anceps, copyright Aqiao HQ.


The functional significance of the Aporum section's distinctive leaves remains uncertain. As noted by Carlsward et al. (1997), the fleshy leaves might be taken as an adaptation to water retention. However, though access to water is a consistent concern for epiphytes, the humid rainforests in which Aporum species are found hardly seem the driest of places. Conversely, the effective even distribution of stomata on both sides of leaf resulting from their equitant condition may make it easier for excess water to be released from the plant.

Dendrobium distichum, photographed by Ronny Boos.


Orchids in general are, of course, most often considered by people as ornamental plants. My impression is that the various Aporum species tend not to be among the most widely grown of species though their unusual growth habit might attract interest. This may be due to them not being the easiest of orchids to maintain; they appear to require high humidity and warm temperatures to thrive with a cooler, drier period in the non-growing season. Among the more popular species are Dendrobium anceps and D. keithii, both of which produce small greenish flowers. Those of D. anceps have been described as having a distinct "apple pie" fragrance. Of course, if you happen to be wandering through the jungles of south-east Asia, you might well discover these plants growing of their own accord.

REFERENCES

Carlsward, B. S., W. L. Stern, W. S. Judd & T. W. Lucansky. 1997. Comparative leaf anatomy and systematics in Dendrobium, sections Aporum and Rhizobium (Orchidaceae). International Journal of Plant Sciences 158 (3): 332–342.

Clements, M. A. 2003. Molecular phylogenetic systematics in the Dendrobiinae (Orchidaceae), with emphasis on Dendrobium section Pedilonum. Telopea 10 (1): 247–298.

Schuiteman, A. 2011. Dendrobium (Orchidaceae): to split or not to split? Gardens' Bulletin Singapore 63 (1–2): 245–257.

The Huenellidae

Researchers who deal with the modern marine fauna are used to thinking of brachiopods as a marginal group, their diversity greatly overshadowed on a global scale by the superficially similar bivalves. However, modern brachiopods are but a shadow of their former selves; for much of the Palaeozoic era, their relationship with the bivalves was the inverse of today. Many are the brachiopod lineages that came and went over this time.

External views of ventral (left) and dorsal valves of Huenella triplicata, from Walcott (1924).


The Huenellidae were an assemblage of brachiopods that lived during the late Cambrian and early Ordovician (Amsden & Biernat 1965). They represent early representatives of the Pentamerida, a Palaeozoic order of fairly generalised-looking brachiopods. Within the Pentamerida, they fall within the suborder Syntrophiidina. Syntrophiidinans as a whole are rarely found in the fossil record and as a result remain poorly known. Members of the suborder share a distinctive shape with biconvex valves marked by a dorsal fold and ventral sulcus. That is, the midline of the shell is raised above either side with the ventral valve forming a 'valley' to match the raised 'hill' of the dorsal valve. What, if anything, was the purpose of this arrangement I wouldn't know but modern brachiopods often inhabit locations with a lot of organic silt and/or fine sediment. Perhaps the uneven level of the syntrophiidinan shell helped protect it from burial by a shifting substrate.

Interior view of ventral valve of Radkeina taylori, from Laurie (1997), with scoop-shaped spondylium at upper midline.


Families of Syntrophiidina may be distinguished based on the development of the spondylium, an internal projection at the base of the ventral valve that provided an attachment site for the shell muscles. Members of the Huenellidae possessed either a sessile spondylium or a pseudospondylium, a spondylium-type structure rising from the internal surface of the valve itself rather than from the hinge. Amsden & Biernat (1965) recognised a division of the huenellids between two subfamilies based on the development of the brachiophore plates, projections on the inside of the dorsal valve that would have supported the lophophore. Members of the Huenellinae possessed more developed brachiophores than members of the Mesonomiinae. Outer ornament of the huenellid shell varied from more or less smooth with weak concentric ridges to costate with distinct radiating ridges.

Phylogenetic relationships within the Syntrophiidina do not seem to have been established in detail but the early appearance in the fossil record of huenellids at least raises the question of whether they included the ancestors of later families. As well as other families of the Syntrophiidina, candidates for descent would include members of the suborder Pentameridina as well as of the related order Rhynchonellida. This latter order includes species which survive to the present day so the possibility exists that while the huenellids themselves may be long gone, their legacy may yet live on.

REFERENCE

Amsden, T. W., & G. Biernat. 1965. Pentamerida. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt H. Brachiopoda vol. 2 pp. H523–H552. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas Press: Lawrence (Kansas).

Arranging Nautiloids

For years, the higher taxonomy of cephalopods was expressed as a division between three subclasses: the Nautiloidea, the Ammonoidea and the Coleoidea. Coleoids were the clade of cephalopods that had lost the external shell, ammonoids were a Mesozoic lineage with complex septa dividing the chambers of the shell, and nautiloids were... the rest. From the tiny, possibly benthic, curved cones of the Cambrian where the class began, to gigantic straight-shelled monsters of the later Palaeozoic, to the modern chambered nautilus, all were lumped together as 'nautiloids'. The nautiloid subclass was explicitly understood to include the ancestors of the others but recognition of more phylogenetically coherent subgroups has been hampered by poor understanding about how the various nautiloid lineages were interrelated. And part of the problem in this regard has been uncertainty about just what features of their fossils we should be paying attention to.

Diorama reconstruction of Beloitoceras oncocerids, from the Burpee Museum.


One factor that has drawn attention in recent years has been the arrangement of muscle scars on the shell. Large muscle attachment scars appear as raised annular elevations on the inside of the shell towards the rear end of the body chamber (in practice, they are more often observed in fossils as depressions on the internal mould). In the living nautilus, the muscles attached to these scars function in the retraction of the head (King & Evans 2019). Modern nautilus possess a pair of large lateral scars in an arrangement that has been labelled 'pleuromyarian'. However, many of the earliest cephalopods possessed a ring of numerous small scars, an arrangement referred to as 'oncomyarian'. Other cephalopods might have scars restricted to the dorsal ('dorsomyarian') or ventral ('ventromyarian') midline.

Primary types of muscle scar in nautiloids, from King & Evans (2019). 'D' and 'V' indicate dorsal and ventral, respectively, and arrows indicate direction of aperture.


Another feature that has been called out has been the structure of the connecting rings around the siphuncle. Shelled cephalopods, you will recall, have the shell divided into chambers separated by septa. Though the bulk of the animal is found in the final body chamber, a fleshy cord called the siphuncle runs back through the remaining chambers. In life, the siphuncle is used to control the levels of fluid in the chambers, which in turn controls the animal's buoyancy. The boundary between the siphuncle and the surrounding chamber is marked a toughened sheath, referred to as the connecting ring. In the modern nautilus, the connecting ring is comprised of two layers, an outer calcareous layer and an inner chitinous layer. In comparable fossils, the latter chitinous layer has decomposed after death so only the outer layer is preserved. However, some extinct cephalopod groups preserve evidence of calcification in the inner as well as the outer layer. Based on the distinction between these two siphuncle types, Mutvei (2015) supported dividing most of the nautiloids between two major lineages, the Nautilosiphonata (with a nautilus-type siphuncle) and the Calciosiphonata (with the internally calcified connecting rings).

A couple of years earlier, the same author (Mutvei 2013) had proposed recognition of a superorder Multiceratoidea for nautiloids that combined multiple muscle scars with a nautilus-type siphuncle. Examples of nautiloid orders with such a combination included the Ellesmeroceratida (small nautiloids with densely placed septa), the Oncoceratida (often short, squat nautiloids) and the Discosorida (similarly squat forms with complex bulging connecting rings). All of these were found in the earlier part of the Palaeozoic with the oncoceratids dieing off in the early Carboniferous. Mutvei (2013) also included the coiled Tarphyceratida and the egg-shaped Ascoceratida in this group. Later, King & Evans (2019) redefined this grouping as the Multiceratia, excluding the Tarphyceratida and Ascoceratida on the grounds that they had ventromyarian rather than oncomyarian muscle scars. Mutvei (2013) suggested that, rather than representing retractor muscles, these smaller repeated scars were associated with an outgrowth of the mantle, either as tentacles or a muscular 'skirt', that was used to capture micro-plankton.

Phylogeny of 'nautiloids' supported by King & Evans (2019). Though not shown on this diagram, the majority of authors have suggested that ammonoids and coleoids are descended from Orthoceratida.


King & Evans (2019) proposed a reclassification of the subclass Nautiloidea between five subclasses defined primarily by muscle structure. Apart from the earliest oncomyarian Plectronoceratia, most 'nautiloids' could be divided between two lineages. On one side were the dorsomyarian Orthoceratia (usually thought to include the ancestors of the ammonoids and coleoids). On the other, the oncomyarian Multiceratia would eventually give rise to the ventromyarian Tarphyceratia which in turn included the ancestors of the pleuromyarian Nautilida. Note that many of the reocognised subclasses (and orders) remain paraphyletic but we are at least approaching a more informative picture of cephalopod evolution than the earlier unceremonious dumping into 'Nautiloidea' (I should probably also remind you that, for various reasons, most invertebrate palaeontologists still don't regard strict monophyly as a taxonomic requirement in and of itself).

The usage of muscle scars and connecting rings as classificatory keys is handicapped by the difficulty of observing them. As internal structures, they each require careful preparation of a specimen to observe. And once you've gotten to a position where you can see them, it seems not to be particularly easy to tell just what you're looking at. As a result, muscle scarring and siphon structure remains undescribed for the majority of nautiloid species. Judging the structure of connecting rings seems to be particularly challenging and some have gone so far as to suggest that purported different structures may be the result of post-mortem taphonomic processes (King & Evans 2019). Nevertheless, what we do know suggests that such features remain reasonably consistent within each of the well-recognised nautiloid orders. And Mutvei's (2015) concept of Calciosiphonata vs Nautilosiphonata does largely line up with King & Evans' (2019) dorsomyarian vs oncomyarian-ventromyarian lineages. There are, of course, some notable exceptions. Whether these will cause the developing structure to collapse, or whether they indicate mistakes in interpretation, only continued research will tell.

REFERENCES

King, A. H., & D. H. Evans. 2019. High-level classification of the nautiloid cephalopods: a proposal for the revision of the Treatise Part K. Swiss Journal of Palaeontology 138: 65–85.

Mutvei, H. 2013. Characterization of nautiloid orders Ellesmerocerida, Oncocerida, Tarphycerida, Discosorida and Ascocerida: new superorder Multiceratoidea. GFF 135 (2): 171–183.

Mutvei, H. 2015. Characterization of two new superorders Nautilosiphonata and Calciosiphonata and a new order Cyrtocerinida of the subclass Nautiloidea; siphuncular structure in the Ordovician nautiloid Bathmoceras (Cephalopoda). GFF 137 (3): 164–174.

A Brief Spotlight on Scopariines

The moths of the Pyraloidea are perhaps one of the more under-appreciated sectors of lepidopteran diversity. With many thousands of species, they comprise a significant proportion of the order in terms of both taxonomic and ecological diversity. Nevertheless, with most species being small and dull in coloration, many Lepidoptera enthusiasts will tend to lump them in the too-hard basket for study. One subgroup of the pyraloids to which this issue definitely applies is the subfamily Scopariinae.

Scoparia spelaea, copyright Donald Hobern.


Close to 600 species of Scopariinae are known from around the world with the highest diversity found on tropical mountains and islands (Léger et al. 2019). They are mostly a mottled greyish in coloration, blending in among the rocks and tree trunks on which they settle during the day. Like other pyraloids, they have large palps that extend in front of the head; pyraloids as a whole are sometimes referred to as 'snout moths' in reference to the appearance this gives them. Forewing venation is characterised by clear separation of vein R2 from R3+4 and absence of CuP (Nielsen & Common 1991).

Meadow grey Scoparia pyralella, copyright Hectonichus.


The majority of scopariine species feed as larvae on mosses, living concealed within a slight silk web. A smaller number feed on dicotyledons or lichens. One New Zealand species, the sod webworm Eudonia sabulosella, has been known to cause economic damage to pasture during sporadic outbreaks. Other species generally do not cause significant impact to humans.

Eudonia lacustrata, copyright Tony Morris.


Identification of scopariines is notoriously difficult with many species closely approximating each other in pattern or exhibiting confounding intra-specific variation. The two largest genera Scoparia and Eudonia can only be reliably separated by examination of the genitalia. Two genera, the Indo-Australian Micraglossa and the Neotropical Gibeauxia, are distinguished by the presence of shiny golden scales on head, thorax and abdomen. With such significant challenges to their study, it would not be surprising if 600 species should turn out to be a marked under-estimate of their true diversity.

REFERENCES

Léger, T., B. Landry & M. Nuss. 2019. Phylogeny, character evolution and tribal classification in Crambinae and Scopariinae (Lepidoptera, Crambidae). Systematic Entomology 44: 757–776.

Nielsen, E. S., & I. F. B. Common. 1991. Lepidoptera (moths and butterflies). In: CSIRO. The Insects of Australia: A textbook for students and research workers 2nd ed. vol. 2 pp. 817–915. Melbourne University Press: Carlton (Victoria).