Salpidobolus

The photo above (copyright Dmitry Telnov) shows a millipede of the genus Salpidobolus, photographed in West Papua. Salpidobolus is a genus of the family Rhinocricidae (in the order Spirobolida) that is found over a range from the Philippines, Sulawesi and Lombok in the west to Fiji in the east and Queensland in the south. There are also a handful of species that have been described from northern South America as part of Polyconoceras, a genus now regarded as synonymous with Salpidobolus, but Hoffman (1974) expressed the expectation on biogeographical grounds that future revision will show these species to be misplaced. Salpidobolus species are scavengers of vegetable matter and most active at night. When threatened, they can release a caustic spray from glands on the body segments that can cause irritation if it contacts mucous membranes such as around the eyes (Hudson & Parsons 1997). There are also reports (albeit unconfirmed) of production of bioluminescence by Salpidobolus (see here); observations on other millipedes suggest such bioluminescence could be related to the aforementioned caustic spray.

As has been mentioned in an earlier post, most millipedes tend not to be extravagant in their external variation, and spirobolidan millipedes look about as millipede-y as you can get. Notable features of the spirobolids as a whole include the presence of only a single pair of legs on each of the first five body rings, and modification of the eight and ninth pairs of legs into the gonopods (Milli-PEET). The Rhinocricidae are characterised by a broad collum (the first segment behind the head) with a rounded ventrolateral margin, and the anterior gonopods forming a single, more or less triangular, transverse plate. Sensory pits called scobinae are often present on the dorsal segments (Marek et al. 2003). Below the family level, as with other millipedes, it all comes down to genitalia. In Salpidobolus, the distal section of the posterior gonopods is flagellate and divided into two branches, one branch carrying the seminal channel (Hoffman 1974).

Gonopods of Salpidobolus meyeri, from Hoffman (1974).

The status of Salpidobolus was most recently reviewed by Hoffman (1974). The majority of species now included in the genus had previously been placed in the separate genera Dinematocricus or Polyconoceras. Salpidobolus was initially restricted to the type species, S. meyeri from Sulawesi, which differs from other species in the presence on the first three pairs of legs of distinct processes on some of the leg segments. Dinematocricus and Polyconoceras were supposed to differ on the basis of the number of sensilla at the end of each antenna: four in Dinematocricus, more than four in Polyconoceras. Hoffman felt that none of these differences warranted generic separation in light of the consistency of gonopod structure between the three 'genera', and united them all under the oldest available name.

REFERENCES

Hoffman, R. L. 1974. Studies on spiroboloid millipeds. X. Commentary on the status of Salpidobolus and some related rhinocricid genera. Revue Suisse de Zoologie 81(1): 189–203.

Hudson, B. J., & G. A. Parsons. 1997. Giant millipede ‘burns’ and the eye. Transactions of the Royal Society of Tropical Medicine and Hygiene 91: 183–185.

Marek, P. E., J. E. Bond & P. Sierwald. 2003. Rhinocricidae systematics II: a species catalog of the Rhinocricidae (Diplopoda: Spirobolida) with synonymies. Zootaxa 308: 1–108.

Stunning Central American Millipedes

Blue cloud forest millipede Pararhachistes potosinus, copyright Luis Stevens.

For my semi-random selection of taxon to write about this week, I drew the millipede family Rhachodesmidae. Rhachodesmids are members of the millipede group called the Polydesmida, characterised by the presence of lateral keels on each segment of the body. The presence of these keels had lead to platydesmidans sometimes being referred to as 'flat-backed millipedes' though depending on how strong the keels are, not all species are necessarily 'flat-backed'.

In an earlier post on millipedes, I stressed the importance of genitalia in characterising millipedes, and the Rhachodesmidae are no exception. In polydesmidans, it is the front pair of legs on the seventh segment that is modified into the gonopods in males (with one notable exception that I may refer to later). Gonopods of rhachodesmids lack the solenite or coxal spur found in many other polydesmidans, and the inner side of the gonopod has a distinct elongate or oval concavity that is densely setose. Other noteworthy features of rhachodesmids are that they are often relatively large, with a conical terminal segment and more or less thickened rims to the lateral keels (Loomis 1964).

An unidentified rhachodesmid, copyright Sergio Niebla.

Beyond that, rhachodesmids become a little more difficult to characterise. Though they are not a widespread group, being restricted to Mexico and Central America, they are very diverse in appearance. Loomis & Hoffman (1962) commented that, "Rhachodesmoids collectively are members of a group notable for great variability and the development of bizarre features. Among their ranks we find millipeds which are bright blue, green, orange, and even pure white as adults; here the gonopod structure ranges from the normal polydesmoid appearance down to monoarticular fused remnants. Body form varies from a slender juliform shape to broad, flat, limaciform contour. Within the limits of this so-called single family occurs more variation than in all of the remaining polydesmoids." They also noted that the group was in need of review, something that apparently remains undone to this day (though there is someone working on it). If the photographs I've commandeered in this post are any indication, this is definitely a group that deserves more love.

Paratype of Tridontomus procerus, from Loomis & Hoffman (1962).

Loomis & Hoffman (1962) made their comments in comparing the Rhachodesmidae to another Central American polydesmidan family they were then describing as new, the Tridontomidae, and if I'm referring to the rhachodesmids then I should probably give a shout-out to these remarkable beasts as well. So far as I've found, this family is still only known from two species, Tridontomus procerus and Aenigmopus alatus, from Guatemala. Not only is the appearance of tridontomids striking, with long spinose processes on either side of the body, but the genital morphology of one species, A. alatus, is especially bizarre: it doesn't have any where it should. Where males of other polydesmidans have the legs of the seventh segment modified into gonopods, those of A. alatus have a perfectly ordinary pair of walking legs. In normal polydesmidans, the gonopods are used to transfer sperm from seminal processes on the coxae of the second pair of legs to the female's genital opening (more details are available here), but obviously Aenigmopus must do things differently. The seminal processes are still present, and the second legs themselves are thickened compared to other millipedes; it is possible that they are somehow used to transfer sperm directly from process to female without the use of gonopods. However it does it, there is no question that Aenigmopus is unique in the world of polydesmidans.

REFERENCES

Loomis, H. F. 1964. The millipeds of Panama (Diplopoda). Fieldiana: Zoology 47 (1): 1-136.

Loomis, H. F., & R. L. Hoffman. 1962. A remarkable new family of spined polydesmoid Diplopoda, including a species lacking gonopods in the male sex. Proceedings of the Biological Society of Washington 75: 145-158.

Giant Centipedes (That Aren't All Giants)

Scolopendra morsitans, copyright Jiri Lochman/Lochman Transparencies.

It was a dark night, but not stormy (nights tend to be dark, as a rule). We were out collecting for our regular survey when we encountered a large centipede (the same species as in the photo above) crossing the road, and decided to add it to our collection. Taking out the large 20-cm forceps that we had on hand for dealing with venomous animals, one of us used them to grab the centipede.

The response was electric. Rather than trying to escape its attacker, the centipede instantly whipped back and lashed itself around the forceps, doing its best to bite into them. Had the actual wielder of the forceps been within its reach, they would have been in for a world of pain. When dealing with scolopendrid centipedes, you should always remember three things: they are big, they are fast, and they are mean.

Scolopendridae are unmistakeable. They include the giants of the centipede world, with the largest species (the South American Scolopendra gigantea) reaching up to a foot in length. Even the smaller species are relatively robust compared to other centipedes. Like all centipedes, the first pair of legs is modified into a robust pair of 'fangs' used for delivering venom (when I referred above to a centipede 'biting', this is what I was properly referring to). Large scolopendrids have the most dangerous centipede stings, potentially causing intense pain, though fatalities are very rare (Bush et al., 2001, noted that no centipede fatalities were known from the US, though they did refer to a single known child fatality in the Philippines). Their hunting prowess is amply demonstrated in this video of a large scolopendrid hunting bats by quite literally snatching them out of the air:


But lest you think that scolopendrids are all venom and viciousness, let me point out that they also have their endearing qualities. Female scolopendrids make devoted mothers, coiling around their egg clutches and regularly cleaning them to prevent fungal attack. Even after the eggs hatch, the female continues to coddle and groom her young. Brunhuber (1970) recorded that females of Cormocephalus anceps spent at least three months (from late September to late December) caring for young before they struck out on their own. Even after becoming independent, the young do not reach sexual maturity until they are at least two years old. Other scolopendrids may mature more quickly, at about one year (Lewis 1972). Individual centipedes may live for several years.

Female Scolopendra morsitans cleaning her eggs, copyright H. J. B..

The Scolopendridae belong to a larger centipede group called the Scolopendromorpha. Most scolopendromorphs have bodies with 21 or 23 leg-bearing segments, except for one remarkable scolopendrid species from central Brazil that has 39 or 43 leg-bearing segments (Chagas-Junior et al. 2008). Non-scolopendrid species are often much smaller than the Scolopendridae, with some being only about 10 mm in length. These smaller scolopendromorphs also differ in eye morphology: Scolopendridae have a patch of four ocelli on either side of the head, but other scolopendromorphs are mostly blind and lack ocelli. In the past the blind scolopendromorphs have been treated as a single family Cryptopidae, but recent authors have mostly recognised three separate families Cryptopidae, Scolopocryptopidae and Plutoniumidae in light of uncertainty about the monophyly of a broader Cryptopidae. Nevertheless, a recent phylogenetic analysis by Vahtera et al. (2012) combining both morphological and molecular data did support a single blind clade. Unfortunately, no phylogenetic analysis to date has been able to include Mimops orientalis, an odd scolopendromorph known from a single specimen collected in China in 1903 and placed by Lewis (2006) in its own distinct family. Mimops possesses but a single ocellus on either side of the head, potentially making it very intriguing for the question of whether blindness has evolved in scolopendromorphs more than once.

The blind scolopendromorph Scolopocryptops sexspinosus, copyright Troy Bartlett.

REFERENCES

Brunhuber, B. S. 1970. Egg laying, maternal care and development of young in the scolopendromorph centipede, Cormocephalus anceps anceps Porat. Zoological Journal of the Linnean Society 49 (3): 225-234.

Bush, S. P., B. O. King, R. L. Norris & S. A. Stockwell. 2001. Centipede envenomation. Wilderness and Environmental Medicine 12 (2): 93-99.

Chagas-Junior, A., G. D. Edgecombe & A. Minelli. 2008. Variability in trunk segmentation in the centipede order Scolopendromorpha: a remarkable new species of Scolopendropsis Brandt (Chilopoda: Scolopendridae) from Brazil. Zootaxa 1888: 36-46.

Lewis, J. G. E. 1972. The life histories and distribution of the centipedes Rhysida nuda togoensis and Ethmostigmus trigonopodus (Scolopendromorpha: Scolopendridae) in Nigeria. Journal of Zoology 167 (4): 399-414.

Lewis, J. G. E. 2006. On the scolopendromorph centipede genus Mimops Kraepelin, 1903, with a description of a new family (Chilopoda: Scolopendromorpha). Journal of Natural History 40 (19-20): 1231-1239.

Vahtera, V., G. D. Edgecombe & G. Giribet. 2012. Evolution of blindness in scolopendromorph centipedes (Chilopoda: Scolopendromorpha): insight from an expanded sampling of molecular data. Cladistics 28: 4-20.

The Importance of Genitalia

Take a look at the figure above (taken from Mauriès 2003). What you're looking at is the intimate business of a male millipede, in this case a Bosnian millipede called Fagina silvatica. And if you ever had the pleasure of finding yourself working on millipede taxonomy, you'd be looking at a lot of these.

Fagina silvatica belongs to a superfamily of millipedes called the Neoatractosomatoidea, which is in turn part of the order Chordeumatida in the clade Helminthomorpha. Helminthomorph millipedes (as indicated by their name, which means 'worm-like') all cleave pretty closely to the classic image of their kind, with an elongate body bearing large numbers of relatively short legs. Chordeumatida are characterised by having silk-spinning glands on the telson, the very end segment of the body, and three pairs of strong bristles on the top of each body segment. Male chordeumatidans also have the eighth and ninth pairs of legs modified into the gonopods, the copulatory structures. Because millipedes are generally not extravagant animals in overall appearance, it is the gonopods that have become the primary structures for identifying them, and many millipede species cannot be reliably distinguished without examining them. In the Neoatractosomatoidea, the eighth pair of legs forms the gonopods proper that deliver the male's sperm to the female's vulvae, while the ninth pair form protective structures called paragonopods. The gonopods proper are divided into two branches that fold around each other, usually to guide a whip-like flagellum or other extended structure passing between them (one genus, Guizhousoma, lacks the flagellum—Mauriès 2005). One neoatractosomatoid genus, Osellasoma, also has the seventh pair of legs modified into protective structures (Mauriès 2003). Neoatractosomatoids have 28 or 30 body segments. Some neoatractosomatoids have the sides of the body extended into flattened processes called paraterga; others have the body more or less cylindrical. And no, I haven't been able to find a single photograph or illustration showing a neoatractosomatoid in its entirety. You'll have to content yourself with looking at their genitals (Wikipedia has photos of other Chordeumatida).

As defined by Mauriès (2003, 2005), the Neoatractosomatoidea only includes about 25 known species, mostly found in southern Europe. A single species, the aforementioned Guizhousoma latellai, is known from caves in China. Mauriès (2003) separated three families previously placed in the Neoatractosomatoidea into a separate superfamily Mastigophorophylloidea; if the mastigophorophylloids are included with the neoatractosomatoids, then the group includes further species found in northern Asia. Mauriès separated the two superfamilies on the basis that mastigophorophylloids possessed a flagellum on both the gonopods and the paragonopods, instead of only on the gonopods. The subsequent discovery of the entirely flagellum-less Guizhousoma could raise questions about the significance of this character, and the flagellum appears much reduced if not entirely absent on the paragonopods of at least one putative mastigophorophylloid, Kirkayakus pallidus, as illustrated by Mikhaljova (2004)*. However, I have to admit to having absolutely zero experience with interpreting millipede gonopods, so I am hardly one to be voicing an opinion.

*Mikhaljova (2004) illustrates this species under the name of Altajella pallida, but it has since been renamed by Özdikmen (2008) (yes, that Özdikmen) due to the original genus being preoccupied).

REFERENCES

Mauriès, J.-P. 2003. Schizmohetera olympica sp.n. from Greece, with a reclassification of the superfamily Neoatractosomatoidea (Diplopoda: Chordeumatida). Arthropoda Selecta 12 (1): 9-16.

Mauriès, J.-P. 2005. Guizhousoma latellai gen.n., sp.n., de Chine continentale, type d'une nouvelle famille de la superfamille des Neoatractosomatoidea (Diplopoda: Chordeumatida). Arthropoda Selecta 14 (1): 11-17.

Mikhaljova, E. V. 2004. The Millipedes (Diplopoda) of the Asian Part of Russia. Pensoft: Sofia.

Özdikmen, H. 2008. New family and genus names, Kirkayakidae nom. nov. and Kirkayakus nom. nov., for the millipedes (Diplopoda: Chordeumatida). Munis Entomology & Zoology 3 (1): 342-344.

The Terrestrial Fauna of Barrow Island

Nihara R. Gunawardene, Jonathan D. Majer, Christopher K. Taylor & Mark S. Harvey (eds) 2013. The Terrestrial Invertebrate Fauna of Barrow Island, Western Australia. Records of the Western Australian Museum, Supplement 83. 406 pp.

For several years now, my colleagues and I have been monitoring terrestrial invertebrates on Barrow Island here in Western Australia. Some of you will have already heard of Barrow Island; for anyone that hasn't, Barrow is the second-largest island off the coast of WA (it's about 25 km long and 12 km wide). It has two main claims to fame: (a) it has been a recognised nature reserve for over 100 years, with thriving populations of a number of animals that are rare or extinct elsewhere, and (b) for the last 50 years, it has also been a working oil field, most recently managed by the oil company Chevron. It also lies close to large offshore natural gas deposits, and in 2003 Chevron and its associates were given permission to build a processing plant on Barrow Island for extraction of the gas. This permit, however, carried strong caveats: development of the plant is not to compromise the value of Barrow as a nature reserve. That's where we come in: on a regular basis, we travel to the island to look for any undesirables that may have managed to slip through the stringent quarantine requirements that have been placed on transport to Barrow (nothing so far, touch wood). Before plant development was begun, a large-scale survey was also conducted to identify the pre-existing invertebrate fauna of Barrow Island: before you can say whether something isn't there, you need to be able to say what is.

Over the course of these surveys, a sizeable collection of material has been accumulated from an area that had previously been only sporadically sampled. Over two dozen taxonomic experts were consulted in the process of identifying this material, a lot of which represented species potentially new to science. And so, some time in 2012, we asked the people who had been involved with the project if they would like to contribute to a collection of papers on Barrow Island invertebrates. The response was mostly positive, and The Terrestrial Invertebrate Fauna of Barrow Island, Western Australia was released to the world a couple of weeks ago.

We're very pleased with how it turned out. Some of the contributors provided overviews of their taxon of interest; others provided descriptions of new species. Authors came from both the academic and private sectors, and we're grateful to everyone who put time and effort into answering our calls. In the end, we had 22 chapters on hand, including material on animals from arachnids to isopods to ants, and 25 new species: one snail, two spiders, a silverfish and 21 flies. Not all of these new species were from Barrow Island alone: the chapter on Dolichopodidae (long-legged flies) by Dan Bickel represents a review of the fauna of the entire Pilbara region.

The book is available for purchase from the Western Australian Museum, but I've noticed that their site doesn't provide an article listing. Therefore, I'm including one below, with the abstracts for each article. Contact details for the corresponding authors have been included as hyperlinks, if you want to ask them about their articles. And again, thank you to everyone involved.

The camaenid snail Rhagada barrowensis. The identity of Barrow Island's common Rhagada species has been subject to a bit of confusion over the years; Johnson et al. describe it as a new species in this book.

Dorian Moro and Russell Lagdon, pp. 1-8.
History and environment of Barrow Island

Barrow Island represents a unique island ecosystem off north-western Australia. It has ecological affinities to the Cape Range region of the Australian mainland, and it also supports an oil and gas resource industry. The island hosts a long-unburnt vegetation complex, and a diverse community of vertebrate and invertebrate fauna occupy the disturbed and undisturbed habitats of the island. In the absence of non-indigenous predators or herbivores, without extensive land clearing, and with an instituted level of island quarantine, these environmental values have persisted to make Barrow Island an important environmental asset for Australia, and an example where island ecology functions in the presence of resource extraction. To date, almost 2,800 species of terrestrial and subterranean species have been consistently recorded from Barrow Island. These include 378 native plant species, 13 mammal species (including two species of bats), at least 119 species of terrestrial and migratory birds, 43 species of terrestrial reptiles, one species of frog, three subterranean vertebrates, at least 34 species of subterranean invertebrates, and the most speciose of all, over 2,200 terrestrial invertebrates.

Russell Lagdon and Dorian Moro, pp. 9-11.
The Gorgon gas development and its environmental commitments

Chevron has made an important contribution to our knowledge and understanding of the Barrow Island flora and fauna, and to the Australian economy. This knowledge has been primarily founded from the investigations and commitments of joint venture partners associated with the environmental impact assessment for the Gorgon Gas Development. The Gorgon Gas Development is one of the world’s largest natural gas projects and the largest single natural gas project in Australia’s history. Development has been balanced between energy needs and environmental management. Through plans, procedures, programs and research, Chevron Australia and its joint venture participants have established a benchmark for environmental management of this important island reserve. Furthermore, the Gorgon Joint Ventures have contributed to one of the largest biodiversity offset and Net Conservation Benefit programs in Western Australia.

Jonathan D. Majer, Shae K. Callan, Karl Edwards, Nihara R. Gunawardene and Christopher K. Taylor, pp. 13-112.
Baseline survey of the terrestrial invertebrate fauna of Barrow Island

Barrow Island is Western Australia’s second largest offshore island and its flora and fauna have been able to evolve without major human disturbances. Chevron Australia Pty Ltd and its Joint Venture Participants made an application to construct a plant to liquefy natural gas on the island in 2001. One of the conditions under which approval was granted was the implementation of a rigorous biosecurity effort to ensure that no non-indigenous species (NIS) are introduced or allowed to establish on the island. To fulfil this condition it was first necessary to characterise what was already present on the island. A series of surveys have been performed using a purpose-designed sampling protocol in order to provide baseline data on the existing terrestrial invertebrates on Barrow Island. A total of 1,873 morphospecies were sampled but subsequent surveys and taxonomic developments have increased the count to 2,397. This compares with an estimated species richness of 2,481 terrestrial invertebrate species on the island. Composition of the fauna varied considerably between the wet and dry seasons and between years, even when samples were taken during the same month. Composition also varied with distance from the coast, which may be associated with soil type and vegetation association. Twenty five non-indigenous species and seven putative non-indigenous species have been found, all of which are believed to have been present prior to commencement of the Gorgon Gas Development project.

Peter Whittle, Frith Jarrad and Kerrie Mengersen, pp. 113-130.
Design of the quarantine surveillance for non-indigenous species of invertebrates on Barrow Island

The Ministerial conditions for regulatory approval for the Gorgon gas project on Barrow Island included a quarantine surveillance program having detection power of 0.8 for non-indigenous species of terrestrial invertebrates, vertebrates and plants. No method was available for design of such a program, so we developed a new method and designed surveillance systems that were implemented successfully in 2010−11 for the first of four years over the construction period. Here we describe the method and outline the invertebrate surveillance system, after the experience of the first year. We discuss a set of issues that characterised the design problem, which we consider typical of many surveillance applications. We suggest that the method is broadly applicable for objective design of surveillance, for biosecurity and other settings.

Ken Walker, pp. 131-134.
Providing web based diagnostics for the Barrow Island baseline survey

During the years of 2005 to 2007, an extensive baseline study of the Barrow Island invertebrate fauna was conducted. This survey included more than 50 sample sites across the island and multiple collecting techniques were used at each site. Over 14,000 specimens were collected during this survey. Taxonomic specialist who examined this material nominated over 2,000 morphospecies of which about 300 could be placed to species rank. Having done all of this collecting and identification, the question then was how best to access and use this valuable resource. All of the specimens were stored in two institutions in Perth – several thousand kilometres south of Barrow Island. Manual access to these specimens was slow which hindered the decision making processes needed when a suspected non-indigenous species was found on the island. The decision was made to digitise the diagnostic characters for representative of each morphospecies. These images were to be made available through a website called PaDIL (Pests and Diseases Image Library). Each species was to have its own webpage containing at least 4 diagnostic images of each species and all of the species collection points to be displayed on an interactive Google Map. Species, as well as higher ranks, could be queried alone or against sample localities or against Indigenous or Non-Indigenous status. Individual species pages could be opened and comparative images tables could be pre-defined and presented or users could build their own comparative image tables in real time. The development of the Barrow Island PaDIL website made the results of the entire Baseline Study accessible to anyone with a web browser from anywhere with an internet connection. The Barrow Island PaDIL website is a major part of the Quarantine efforts of Chevron on Barrow Island.

Christopher K. Taylor, pp. 135-144.
Annotated bibliography for Barrow Island terrestrial invertebrates

A bibliography is provided of publications treating terrestrial invertebrates on Barrow Island. A brief overview is also given of natural history and invertebrate collections on Barrow Island.

Garth Humphreys, Jason Alexander, Mark S. Harvey and William F. Humphreys, pp. 145-158.
The subterranean fauna of Barrow Island, north-western Australia: 10 years on

Barrow Island, situated off the north-west Australian coast, is well recognised for its subterranean fauna values. Sampling for both stygobitic and troglobitic fauna has taken place on the island since 1991, and Humphreys (2001) summarised the then current state of knowledge of the island’s subterranean fauna. Sampling for impact assessment purposes on the island over the past decade has substantially increased the recorded species richness of Barrow Island. The number of documented stygal taxa has more than doubled since 2001, from 25 to 63 species now known. Troglobitic diversity has also substantially increased, with six species known in 2001 and 19 troglobitic taxa known today. The total recorded subterranean species richness for Barrow Island at this time stands at 82 species. It is likely that considerably more species remain to be recorded, as even the additional surveys of the past decade leave many areas of the island unsampled.
The distributions and minimum area of occupancy for many species known from Barrow Island in 2001 have also been significantly expanded by the sampling efforts of the last decade. This includes specially protected species listed under State and Commonwealth Government legislation. The available data suggest the fauna of the island may number in the hundreds of species, many of which are endemic, confirming its status as internationally significant for subterranean biota.

Michael S. Johnson, Sean Stankowski, Corey S. Whisson, Roy J. Teale and Zoë R. Hamilton, pp. 159-171.
Camaenid land snails on Barrow Island: distributions, molecular phylogenetics and taxonomic revision

Three species of camaenid land snails occur on Barrow Island: Quistrachia barrowensis and two previously unassigned species of Rhagada. Based on morphological re-evaluation and analysis of sequences of the mitochondrial gene COI, we have revised the taxonomy of these species, providing a clearer understanding of their geographic distributions and origins. The supposed Barrow Island endemic Q. barrowensis is synonymous with Q. montebelloensis from the Montebello and Lowendal Islands. The small species of Rhagada, confined to the northern tip of Barrow Island, is conspecific with R. plicata, whose distribution also includes the Montebellos and the Lowendals. The large species of Rhagada is described here as R. barrowensis sp. nov., known only from Barrow Island and adjacent Pascoe Island. The three camaenids represent deeply divergent lineages with different geographic origins, indicating that the local diversity on Barrow Island has come about through a complex history. With maximum geographic spans of only 22 to 70 km, the short-range endemism of these species highlights the conservation significance of Barrow Island.

Volker W. Framenau and Anna E. Leung, pp. 173-184.
Costacosa, a new genus of wolf spider (Araneae, Lycosidae) from coastal north-west Western Australia

A new genus of wolf spider (family Lycosidae Sundevall, 1833), Costacosa gen. nov. is described from north-west Western Australia to include C. torbjorni sp. nov. (type species) and C. dondalei sp. nov. The genus belongs to the subfamily Lycosinae Sundevall, 1833 and differs from all other Australian genera in this subfamily with similar somatic morphology, in particular Venator Hogg, 1900 and Knoelle Framenau, 2006, mainly in genitalic characters. The tegular apophysis of the male pedipalp has a pronounced ventral spur, a distinct ventral edge of species-specific shape and serrations along its apical edge. The female epigyne has an elongated triangular atrium and the medium septum is longer than the posterior transverse part. Costacosa are medium-sized wolf spiders of overall brown colouration and with broad light median and sublateral bands on the carapace and a black patch in the frontal two-thirds of the venter. Costacosa torbjorni is the most commonly recorded wolf spider on Barrow Island, from where currently seven species of Lycosidae are known.

Simon Judd and Giulia Perina, pp. 185-207.
An illustrated key to the morphospecies of terrestrial isopods (Crustacea: Oniscidea) of Barrow Island, Western Australia

This paper presents an illustrated key to eighteen morphospecies of terrestrial isopods from Barrow Island with a brief summary regarding their currently known distribution and potential endemicity to the island. Six described species are recorded, Ligia exotica (family Ligiidae), Alloniscus pallidulus (Alloniscidae), Laevophiloscia yalgooensis (Philosciidae), Porcellionides pruinosus (Porcellionidae), Barrowdillo pseudopyrgoniscus, Buddelundia hirsuta (both Armadillidae), but the identifications of most need to be confirmed following genus-level revisions and examination of type- or topotypical material. The key includes twelve undescribed species and at least two undescribed genera from the family Armadillidae, one of which is apparently restricted to Barrow Island. Although there is still considerable taxonomic work required to evaluate distributions, it appears that at least six of the eighteen species are potential short-range endemics (SRE).

Catherine A. Car, Megan Short, Cuong Huynh and Mark S. Harvey, pp. 209-219.
The millipedes of Barrow Island, Western Australia (Diplopoda)

Six species of millipedes are recorded from Barrow Island, including three species of pin-cushion millipedes of the order Polyxenida, Lophoturus madecassus (Marquet and Condé, 1950) (Lophoproctidae), Unixenus mjoebergi (Verhoeff, 1924) (Polyxenidae) and Phryssonotus novaehollandiae (Silvestri, 1923) (Synxenidae), a single species of the order Spirobolida, Speleostrophus nesiotes Hoffman, 1994 (Trigoniulidae), and two species of the order Polydesmida, Boreohesperus dubitalis Car and Harvey, 2013 (Paradoxosomatidae) and one species of the family Haplodesmidae (genus and species indet.). Lophoturus madecassus is circum-tropical in distribution, Unixenus mjoebergi and Phryssonotus novaehollandiae are found also on mainland Australia, but the other three species are endemic to the island. Speleostrophus nesiotes is a highly modified troglobiotic species, currently listed as threatened by the Western Australian government. It is unclear at present whether the haplodesmid specimen is a troglobite.

Penelope Greenslade, pp. 221-228.
Composition of Barrow Island collembolan fauna: analysis of genera

Collembola have been collected from Barrow Island for the first time; a maximum of seventy one species were detected, of which a high proportion are undescribed. Only four non-indigenous species (NIS) species have been collected, three in very small numbers but one was a large population introduced to the island in lengths of timber which were subsequently sent off the island. Despite few of the species being described, most have been collected before and endemism is low. One new genus record for Australia, Calx, was found. The presence of a species of Temeritas is unusual in that the males showed strong sexual dimorphism, and a species of Acanthocyrtus that lacked any pigment was collected in reasonable numbers. Collections from bore holes were rich in species. Five species were recorded only from bore holes and may be island endemics. The intertidal fauna was also rich in species with 14 found, all restricted to this habitat. Soil fauna density of Collembola was found to be high, with a mean average potential density of nearly 47,000/m². A proportion of the terrestrial Collembola fauna is active under all weather conditions but other species are only active after rain. In general, the terrestrial fauna shows a dominance of the families Isotomidae and Bourletiellidae, which is typical for the wet/dry tropics where trees are absent.

Graeme Smith, pp. 229-240.
A new species of Heterolepisma from Barrow Island (Zygentoma: Lepismatidae)

The silverfish fauna of Barrow Island is discussed and Heterolepisma parva sp.nov. is described from extensive material collected mostly in pitfall traps or Winkler sac leaf litter samples.

David T. Jones, pp. 241-244.
The termites of Barrow Island, Western Australia

Forty years ago D. H. Perry, the renowned termite expert, published a checklist of 18 species that he had collected on Barrow Island. That checklist is now updated with the results of a recent invertebrate survey of the island, and a literature search for additional records. The updated list now runs to 27 species, all of which appear to be indigenous to the island.

Christopher K. Taylor, pp. 245-252.
The genus Lithoseopsis (Psocodea: Amphientomidae) in the Western Australian fauna, with description of the male of Lithoseopsis humphreysi from Barrow Island

The Australian Amphientomidae species Seopsis incisa Smithers, 1989 and S. humphreysi New, 1994 are transferred to the genus Lithoseopsis Mockford, 1993 as L. incisa new combination and L. humphreysi new combination, as a result of the discovery of speciens of L. humphreysi from Barrow Island, Western Australia. The male of L. humphreysi is described for the first time, and both macropterous and brachypterous individuals are described. The genus Lithoseopsis was previously known from North America only, and the addition of the Western Australian species significantly increases its range. A key is provided to the genera of Amphientomidae.

David Gopurenko, Murray Fletcher, Holger Löcker and Andrew Mitchell, pp. 253-285.
Morphological and DNA barcode species identifications of leafhoppers, planthoppers and treehoppers (Hemiptera: Auchenorrhyncha) at Barrow Island

The hemipteran suborder Auchenorrhyncha comprises a rich assemblage of plant feeding species, many of which are widespread in distribution and act as vectors of viral and fungal diseases affecting plants. Species level identifications in this group generally are possible only by examination of male specimens; prior DNA barcode analyses of a limited range of Auchenorrhyncha indicate that this approach may provide an expedient means to identify species within this diverse group. In this study we explored the utility of DNA barcoding for identification of a wider range of Auchenorrhyncha species than has been examined previously. Diverse fulgoroid (planthopper) and membracoid (leafhopper and allies) Auchenorrhyncha were sampled from Barrow Island, Western Australia, and identified to the least inclusive taxonomic units using morphology. DNA barcodes from 546 adult specimens were obtained and analysed using a General mixed Yule – Coalescent (GMYC) modelling approach to genetically delimit putative species, as a comparison to the morphospecies identifications. Additional DNA barcodes (N = 106) were obtained from nymphs and these were compared to adult DNA barcodes to identify species present among immature specimens.
Among adult specimens, 73 species were congruently delimited by morphology and genetic analyses when modelled using a single threshold GMYC. Congruence between morphological and molecular species assignments was greatly reduced when the Yule – Coalescent transition was allowed to vary across genetic lineages. In a separate DNA barcode analysis of all specimens using neighbour joining distance metrics, nymphs and physically degraded specimens were in most cases genetically linked to adult conspecifics. Ten genetic clades detected among the nymphs were not observed among adults and did not match pre-existing sequence accessions in GenBank or DNA barcode records in BOLD.
Of the 73 adult Auchenorrhyncha species congruently identified by DNA barcoding and morphology, most were Cicadellidae (N = 53 morphospecies), the remaining 20 morphospecies were sparsely representative of ten other families. Formal identifications to species level were available for only 36% of these 73 morphospecies, owing mainly to an absence of diagnostic male specimens within many of the delimited species. Indeterminate species detected among adults and nymphs are designated with interim species codes.
The work presented here demonstrates that DNA barcoding is likely to be a powerful investigative tool for identifying and understanding species limits in the Auchenorrhyncha, particularly if it is used within an integrative taxonomic framework.

Laurence A. Mound, pp. 287-290.
Thysanoptera (Insecta) of Barrow Island, Western Australia

Almost 50 species of the insect order Thysanoptera are here listed from Barrow Island, Western Australia, of which several are known only from this island. This cannot be interpreted as indicating that any species is endemic to the island, because almost nothing is known of the Thysanoptera fauna of the nearby mainland.

Daniel J. Bickel, pp. 291-348.
The family Dolichopodidae (Diptera) of the Pilbara region, Western Australia in its Australasian biogeographic context, with the description of 19 new species

The Dolichopodidae (Diptera) of the Pilbara Region (here also including Barrow Island and Cape Range), Western Australia are described, keyed and illustrated. The fauna comprises 41 species, including three with generic names only, being represented by females or badly damaged males. The following 19 species are newly described: Pseudoparentia canalicula sp. nov., Pseudoparentia niharae sp. nov., Paraclius manglar sp. nov., Medetera junensis sp. nov., Corindia gascoynensis sp. nov., Thinophilus eboricoxa sp. nov., Thinophilus yarraloola sp. nov., Chaetogonopteron capricorne sp. nov., Chaetogonopteron vexillum sp. nov., Sympycnus colliepa sp. nov., Sympycnus lacrimulus sp. nov., Sympycnus pistillus sp. nov., Sympycnus weano sp. nov., Sympycnus ephydroides sp. nov., Sympycnus hamulitarsus sp. nov., Diaphorus karijini sp. nov., Diaphorus garnetensis sp. nov., Chrysotus austrotropicus sp. nov. and Chrysotus pilbarensis sp. nov. Paraclius obtusus Hardy, 1939 is regarded as a new senior synonym of Paraclius albodivisus Parent, 1941, syn. nov. The Pilbara fauna is treated in the context of the wider Australian fauna, and many extralimital records are included. Many Pilbara species are found across tropical northern Australia, and sometimes into adjacent Melanesia. However, some species have a trans-continental distribution south of the monsoonal belt and also occur in central Northern Territory and subtropical interior Queensland suggesting a biogeographic track that now comprises favorable relictual habitats in a largely arid region. The Millstream site along the Fortescue River is particularly rich in species, and it is the only known locality of the isolated monotypic genus Pilbara Bickel.

David K. Yeates and Stefanie K. Oberprieler, pp. 349-354.
Two new species of the Australian bee fly genus Comptosia (Diptera: Bombyliidae) from Barrow Island, Western Australia

Two new species of the bee fly genus Comptosia Macquart from Western Australia, C. barrowensis and C. karijinii, are described.

Nicholas B. Stevens, Syngeon M. Rodman, Tamara C. O’Keeffe and David A. Jasper, pp. 355-374.
The use of the biodiverse parasitoid Hymenoptera (Insecta) to assess arthropod diversity associated with topsoil stockpiled for future rehabilitation purposes on Barrow Island, Western Australia

This paper examines the species richness and abundance of the Hymenoptera parasitoid assemblage and assesses their potential to provide an indication of the arthropod diversity present in topsoil stockpiles as part of the Topsoil Management Program for Chevron Australia Pty Ltd Barrow Island Gorgon Project. Fifty six emergence trap samples were collected over a two year period (2011 and 2012) from six topsoil stockpiles and neighbouring undisturbed reference sites. An additional reference site that was close to the original source of the topsoil on Barrow Island was also sampled. A total of 14,538 arthropod specimens, representing 22 orders, were collected. A rich and diverse hymenopteran parasitoid assemblage was collected with 579 individuals, representing 155 species from 22 families. The abundance and species richness of parasitoid wasps had a strong positive linear relationship with the abundance of potential host arthropod orders which were found to be higher in stockpile sites compared to their respective neighbouring reference site. The species richness and abundance of new parasitoid wasp species yielded from the relatively small sample area indicates that there are many species on Barrow Island that still remain to be discovered. This study has provided an initial assessment of whether the hymenoptera parasitoid assemblage can give an indication of arthropod diversity. However, further work would still be required to more robustly establish the use of the hymenoptera parasitoid assemblage as indicators of arthropod diversity.

B. E. Heterick, pp. 375-404.
A taxonomic overview and key to the ants of Barrow Island, Western Australia

This work characterises the ant (Hymenoptera: Formicidae) fauna of Barrow Island, Western Australia, and provides a key to the workers and several unique reproductives of the 117 species recorded from the island thus far. In all, 11 of the 13 subfamilies of Western Australian ants have been recorded from Barrow Island, but Myrmeciinae and Heteroponerinae are absent. At a generic level, the fauna of the island is less rich, holding 36 of the 71 genera currently known from Western Australia. The ant fauna is characteristic of the Eremaean Botanical Province of the Pilbara, rather than that of the Carnarvon Basin from which Barrow Island is geologically derived. Ninety-three ant species (79.5% of the total on Barrow Island) are shared with the ant fauna of the Pilbara region on the adjoining mainland, but only 52 species (44.4% of the total) are shared with the ant fauna of the Carnarvon Basin. The island is very rich in unspecialised and thermophilic ant species. Five such genera, i.e., Iridomyrmex (14 spp.), Monomorium (13 spp.), Polyrhachis (12 spp.), Melophorus (10 spp.), and Camponotus (nine spp.) make up almost 50% (i.e., 49.6%) of the island’s ant fauna. Very few ants appear to be endemic to Barrow Island. The relative proportions of the two major subfamilies (Formicinae and Myrmicinae, together comprising 61.5% of the total ant richness) are similar to the proportions found in the South-west Botanical Division for these two subfamilies (i.e., 65.9%), with Barrow Island having a slightly lower ratio of formicines to myrmicines than is found in the south-west of the state. An estimate of the total number of ant species likely to occur on Barrow Island, using the Estimate-S program (Colwell 2009), suggests that a maximum of fourteen additional species may be as yet unrecorded.

Jonathan D. Majer, Nihara R. Gunawardene, Christopher K. Taylor and Mark S. Harvey, pp. 405-406.
A last word

The work reported on in this volume is the culmination of nine years of data gathering stemming from the original baseline surveys on Barrow Island. Not surprisingly, this has resulted in one of the most comprehensive terrestrial invertebrate surveys ever performed on an offshore island on this continent. There are other substantial surveys, but these have generally focussed on specific taxonomic groups, rather than the whole spread reported here.