First phylogenetic analysis of the Nearctic madicolous midges of the genus Androprosopa Mik (Diptera: Thaumaleidae).

Molecular phylogenetic analyses were conducted to infer relationships between the eastern and western Nearctic Androprosopa Mik and amongst the considerably more diverse western Nearctic species. Fresh, molecular-grade material was obtained for all Nearctic Androprosopa species except two Mexican species, An. sonorensis (Arnaud & Boussy) and An. zempoala Sinclair & Huerta, that eluded capture. Molecular sequences from two nuclear protein-coding genes, big zinc finger (BZF) and molybdenum cofactor sulfurase (MCS), were sampled from representatives of several outgroup and ingroup taxa and analyzed phylogenetically using maximum likelihood criteria to confirm identifications of females and immatures using a barcoding approach, test species boundaries among morphologically similar species, and infer relationships among more morphologically disparate groups. Resulting phylogenies suggest the following with significant node (bootstrap) support: (1) the eastern Nearctic Androprosopa species form the sister group to the lineage comprised of all sampled Palearctic thaumaleids, i.e., An. larvata (Mik), An. striata (Okada), and Thaumalea testacea Ruthe; (2) the aforementioned lineage is the sister group to the clade comprised of western Nearctic Androprosopa species; (3) the western Nearctic Androprosopa species form three multispecies lineages, two of which can be further divided into three or more well founded species groups. Our results suggest that Androprosopa as currently defined is paraphyletic. Additionally, we propose several new species groups within the western Nearctic Androprosopa based on molecular and morphological data.

Revision of the genus Niphta (Diptera, Thaumaleidae) Theischinger of South America, with descriptions of nine new species and a new immature morphotype.

The Niphta Theischinger fauna of South America is revised to include 11 species, nine of which are described as new to science (N.acus Pivar, sp. nov., N.bifurcata Pivar & Moulton, sp. nov., N.bispinosa Pivar & Sinclair, sp. nov., N.brunnea Pivar, sp. nov., N.courtneyi Pivar, sp. nov., N.daniellae Pivar, sp. nov., N.downesi Pivar, sp. nov., N.eurydactyla Pivar, sp. nov., N.mapuche Pivar, sp. nov.). The genus Niphta is redefined, both previously described Chilean species are redescribed, N.halteralis (Edwards) and N.nudipennis (Edwards), and females are described or redescribed where possible. The first descriptions of the immature stages of South American Niphta are provided, which represent a new larval morphotype in Thaumaleidae, as larvae and pupae possess ventral adhesive structures. Furthermore, these larvae were collected from vegetation rather than rocky substrates. Illustrations and micrographs are provided for all species, and scanning electron microscopy images are included for select immatures. A key to species, distribution maps, and discussions regarding phylogenetic affinities and habitat are also included.

Polycentropus aileenae n. sp. (Trichoptera: Polycentropodidae), a caddisfly species from the eastern Nearctic, with new state records for members of the Polycentropus confusus Species Group.

A new eastern Nearctic species of tube-making caddisfly of the genus Polycentropus Curtis 1835 (Trichoptera: Polycentropodidae) is described and illustrated based on adult males and females. Polycentropus aileenae n. sp., a member of the Polycentropus confusus Species Group, is reported from the Canadian province Nova Scotia and the U.S. states Tennessee and Pennsylvania. The species is diagnosed based on multiple aspects of the male genitalia, including inflection of the dorsal processes of the preanal appendages and the slightly recurved dorsum of the apex of the phallus. New U.S. state records of P. confusus Hagen 1861 and P. elarus Ross 1944 from Florida, and P. thaxtoni Hamilton Holzenthal 1986 from Alabama, are also provided.

Twenty years of Dipterology through the pages of Zootaxa.

We present a summary and analysis of the Diptera-related information published in Zootaxa from 2001 to 2020, with a focus on taxonomic papers. Altogether, 2,527 papers on Diptera were published, including 2,032 taxonomic papers and 1,931 papers containing new nomenclatural acts, equivalent to 22% of all publications with new nomenclatural acts for Diptera. The new nomenclatural acts include 7,431 new species, 277 new genera, 2,003 new synonymies, and 1,617 new combinations. A breakdown by family of new taxa and new replacement names proposed in the journal during the last two decades is provided, together with a comparison of Zootaxa's output to that of all other taxonomic publications on Diptera. Our results show that the journal has contributed to 20% of all biodiversity discovery in this megadiverse insect order over the last 20 years, and to about 31% in the last decade.

Heth pivari n. sp. (Nematoda: Ransomnematoidea: Hethidae) from the indigenous North American millipede Narceus gordanus (Spirobolida: Spirobolidae), with keys for worldwide Heth spp.

Forty-four specimens of the millipede Narceus gordanus Chamberlin, 1943 (Spirobolida: Spirobolidae) were collected from Alachua, Citrus, Hernando, and Marion counties in peninsular Florida. Morphometric data were recorded for each. Nematodes were dissected from the intestine of each individual and sorted into morphotaxa. Heth pivari n. sp. (Oxyuridomorpha: Ransomnematoidea: Hethidae) was found in 33 (75%) of dissected N. gordanus and examined with brightfield, differential interference contrast, phase contrast and scanning electron microscopies. LSU rDNA sequences of representative males and females of H. pivari n. sp. were analyzed and compared to sequences of nematodes in the infraorder Rhigonematomorpha. Heth mauriesi, an introduced species, also was sequenced. Females of H. pivari n. sp. differ from those of other Heth spp. in having smooth, button-like somatic and cervical papillae and shallow, shield-like cervical collars. Males have slit-like or narrowed, rather than circular, stomal openings. Heth pivari n. sp. is the first species of this genus found in an indigenous millipede north of Mexico. Keys based on female cervical ornamentation are provided to differentiate the 52 known Heth spp.

Revision of the South American species of Austrothaumalea Tonnoir (Diptera: Thaumaleidae).

The Austrothaumalea fauna of South America is revised and includes five species: A. apicalis Edwards, A. chilensis Edwards, A. fredericki Pivar sp. nov., A. setipennis Edwards stat. rev. and A. spatulata Schmid. The genus Oterere McLellan syn. nov. is considered a new junior synonym of Austrothaumalea Tonnoir on the basis of several shared apomorphic characters. All previously described South American species are redescribed, including females where possible. Illustrations and micrographs of all species are provided, as well as distribution maps, keys to genera and species, and discussions regarding phylogenetic affinities.

Austrocnephia, new genus, for five species of 'Paracnephia' (Diptera: Simuliidae), with a key to Australian black fly genera.

A segregate of the so-called Australian 'Paracnephia' (Diptera: Simuliidae) is assigned to a new genus, Austrocnephia. The taxon is fully diagnosed and a key to constituent species presented. Two species-groups are recognized: the aurantiaca species-group, comprised of A. aurantiaca (Tonnoir 1925) and A. strenua (Mackerras Mackerras 1950), and the tonnoiri species-group, comprised of A. fuscoflava (Mackerras Mackerras 1948), A. orientalis (Mackerras Mackerras 1950) and A. tonnoiri (Drummond 1931). Both species-groups are diagnosed and the included species fully redescribed. Detailed locality data is given, as is information about biology, when known. Brief comments are offered about the historical biogeography of Austrocnephia. A key to Australian simuliid genera is also provided.

Molecular phylogeny and evolution of world Tachinidae (Diptera).

We reconstructed phylogenetic relationships within the diverse parasitoid fly family Tachinidae using four nuclear loci (7800 bp) and including an exceptionally large sample of more than 500 taxa from around the world. The position of the earthworm-parasitizing Polleniinae (Calliphoridae s.l.) as sister to Tachinidae is strongly supported. Our analyses recovered each of the four tachinid subfamilies and most recognized tribes, with some important exceptions in the Dexiinae and Tachininae. Most notably, the tachinine tribes Macquartiini and Myiophasiini form a clade sister to all other Tachinidae, and a clade of Palpostomatini is reconstructed as sister to Dexiinae + Phasiinae. Although most nodes are well-supported, relationships within several lineages that appear to have undergone rapid episodes of diversification (basal Dexiinae and Tachininae, Blondeliini) were poorly resolved. Reconstructions of host use evolution are equivocal, but generally support the hypothesis that the ancestral host of tachinids was a beetle and that subsequent host shifts to caterpillars may coincide with accelerated diversification. Evolutionary reconstructions of reproductive strategy using alternative methods were incongruent, however it is most likely that ancestral tachinids possessed unincubated, thick shelled eggs from which incubated eggs evolved repeatedly, potentially expanding available host niches. These results provide a broad foundation for understanding the phylogeny and evolution of this important family of parasitoid insects. We hope it will serve as a framework to be used in concert with morphology and other sources of evidence to revise the higher taxonomic classification of Tachinidae and further explore their evolutionary history and diversification.

Stauratostoma shelleyi n. gen., n. sp. (Nematoda: Rhabditida: Thelastomatidae) from Appalachian Polydesmid Millipedes (Polydesmida: Xystodesmidae).

Stauratostoma shelleyi n. gen., n. sp. is described from the midgut and hindgut of nine species of the millipede family Xystodesmidae collected in the southern Appalachian regions of North Carolina, Tennessee and Alabama. Specimens of S. shelleyi were morphologically examined with differential interference contrast, phase contrast, and scanning electron microscopy. The head of S. shelleyi differs from other thelastomatid nematodes in having a head region mushroom-shaped in profile; cruciform stomatal opening formed from four flaps; greatly expanded labial disc; and eight-sectored annule-like column supporting the labial disc. Thirteen nematodes from various hosts were sequenced for 28S LSU rDNA and compared with other millipede-inhabiting nematodes. Stauratostoma shelleyi is the sister group to the few Thelastoma spp. that have been molecularly characterized using the D2-D3 expansion segments of the 28S LSU rDNA.

A new genus, Protaustrosimulium, for four species of Australian black flies (Diptera: Simuliidae).

Protaustrosimulium n. gen. is described for four species: two previously named species from southeastern Australia-Paracnephia pilfreyi (Davies Györkös 1988) and Paracnephia terebrans (Tonnoir 1925)-plus two newly described ones from the southwestern-most corner of Western Australia-Prot. amphorum n. sp. and Prot. opscurum n. sp. Molecular and morphological data suggest a close relationship between members of the new genus and Austrosimulium Tonnoir 1925. Monophyly of Protaustrosimulium is supported mainly by characters of adult females, as two of the four species are known only in that life stage. Two species groups are recognized: the pilfreyi-group for Prot. pilfreyi and Prot. amphorum, and the terebrans-group for Prot. terebrans and Prot. opscurum. The constituent species in each group are distributed vicariously in southeastern and southwestern Australia-a common biogeographical pattern in Australian simuliids.

Nothogreniera new genus, for two species of Australian "Paracnephia" (Diptera: Simuliidae).

Two species of Australian Simuliidae known only from adult females and currently assigned to "Paracnephia" are re-described, as are their now-known males and immature stages. Morphological character states of "Paracnephia" fergusoni (Tonnoir) and "P." fergusoni var. (Mackerras Mackerras) reveal that they are markedly distinct from all other Australian species, and are here assigned to the new genus-Nothogreniera-the most plesiomorphic Gondwanan Australian simuliid. Structural variation among populations of N. fergusoni suggests that this entity comprises a species complex.

Rediscovery of Dixa repanda Peters and description of its putative sister species, Dixa falcata sp. nov., from the south-central United States (Diptera: Dixidae).

Dixa repanda Peters, previously known only from the type series of three males, was rediscovered after targeted collections in the southcentral and midwestern United States. These collections also revealed the presence of its undescribed putative sister species, Dixa falcata sp. nov. The two species are sympatric in the Ozark Mountains. Adults of D. repanda are redescribed and those of Dixa falcata are described. Males of both species are distinguished from related, similarly colored species by a falcate gonostylus and extremely reduced cercus. Males of the two species are easily separated from each other by the shape and thickness of the gonostylus. Females are not reliably separable from each other or related species. Biological insights, including known distributions, of both species are provided.

Reassignment of Western Australia Paracnephia gladiator Moulton Adler to a new genus, Bunyipellum (Diptera: Simuliidae).

With new material available of most stages of many known Australian Paracnephia, including new species, it is now clear that certain segregates warrant assignment to new genera. This applies to Paracnephia gladiator Moulton Adler, a Western Australia simuliid with numerous unique character states. The species is fully redescribed and assigned to Bunyipellum nov. gen. A diagnosis is provided and relationships discussed, as is historical biogeography. Bunyipellum appears to be more closely related to elements of the South American simuliid fauna than to any other Gondwanan Australian species.

Taxonomic revision of Paraustrosimulium Wygodzinsky & Coscarón: reassignment of Austrosimulium colboi and description of P. obcidens n. sp. from Western Australia.

The hitherto monotypic South American genus Paraustrosimulium Wygodzinsky & Coscarón is revised to accommodate two Australian species: Austrosimulium colboi Davies & Györkös and Paraustrosimulium obcidens n. sp. The generic diagnosis is updated and the eastern Australian species Paraustrosimulium colboi (Davies & Györkös) n. stat. is re-described, including the male for the first time. The Western, Australian sister species of P. colbo, namely P. obcidens Craig, Moulton Currie n. sp. is also fully described. The relationship of Paraustrosimulium to other simuliid genera is discussed, as are aspects of historical biogeography.

The true identity of Dixa modesta Johannsen (Diptera: Dixidae) resolved: synonymy of Dixa similis Johannsen, designation of the Dixa ubiquita species group, and description of three new eastern Nearctic species.

Examination of the lectotype male of Dixa modesta Johannsen revealed this species has a confused taxonomic history. It was discovered that Dixa modesta and Dixa similis Johannsen are based on the same nominal species, the former having priority. As a result, Dixa similis falls into synonymy with Dixa modesta (syn. nov.). The species long considered to correspond to the latter (since 1966 if not earlier), i.e., Dixa modesta sensu Peters, comprises three distinct sibling species based on a combination of morphological and molecular evidence. Adults of each sibling are described herein (D. elkmontensis sp. nov., D. ubiquita sp. nov., D. vockerothi sp. nov.), and the D. ubiquita species group is proposed to include them. Morphological diagnoses and a dichotomous key are provided to separate adult males of the D. ubiquita group from those of all other Nearctic species and each other, respectively. Molecular diagnoses are provided to allow identification of any life stage of these three siblings. Updated life history and distributional data are also reported for each sibling.

Coronostoma claireae n. sp. (Nematoda: Rhabditida: Oxyuridomorpha: Coronostomatidae) from the Indigenous Milliped Narceus gordanus (Chamberlain, 1943) (Diplopoda: Spirobolida) in Ocala National Forest, Florida.

Twenty-four individuals of Narceus gordanus (Diplopoda: Spirobolidae) were collected in Ocala National Forest, FL, between November 2013 and July 2014. Each specimen was dissected to extract the intestine, which was removed and examined for parasitic nematodes. Coronostoma claireae n. sp. was collected from the hindgut and midgut of 10 specimens, and its morphology was examined with brightfield, differential interference contrast, phase contrast, and scanning electron microscopy. This species is separated from other Coronostoma spp. by the following characteristics: body length less than 3 mm; head sense organs pit-like; first annule long, extending past middle of corpus, width similar to that of second annule; basal bulb pyriform; eggs larger than 60 × 50 µm. This species is the first North American record for the genus Coronostoma, which is removed from Thelastomatoidea: Thelastomatidae and reassigned to Coronostomatidae on the basis of presumed apomorphies. A key is provided for known Coronostoma spp. The superfamily Coronostomatoidea is re-established for Coronostomatidae and Traklosiidae.

Phylogenetic placement of two species known only from resting spores: Zoophthora independentia sp. nov. and Z. porteri comb nov. (Entomophthorales: Entomophthoraceae).

Molecular methods were used to determine the generic placement of two species of Entomophthorales known only from resting spores. Historically, these species would belong in the form-genus Tarichium, but this classification provides no information about phylogenetic relationships. Using DNA from resting spores, Zoophthora independentia, infecting Tipula (Lunatipula) submaculata in New York State, is now described as a new species and Tarichium porteri, described in 1942, which infects Tipula (Triplicitipula) colei in Tennessee, is transferred to the genus Zoophthora. We have shown that use of molecular methods can assist with determination of the phylogenetic relations of specimens within the form-genus Tarichium for an already described species and a new species for which only resting spores are available.

The Dixa inextricata Dyar & Shannon (Diptera: Dixidae) species group, with two new cryptic species from the eastern Nearctic Region.

Dixa inextricata Dyar & Shannon is currently regarded as a widespread species in the eastern Nearctic, currently distinguished from sympatric congeners by its brown coloration and triangular gonostylus as seen in lateral view. Recent morphological examination of archival material and dual morphological and molecular examination of recently acquired material fitting the diagnosis of Dixa inextricata revealed the presence of three species. These three species have never been found occupying the same stream in spite of two different pairs of members being geographically and temporally sympatric. The diagnosis of D. inextricata is revised, two closely related species D. appalachiensis sp. nov. and D. calciphila sp. nov., are described and the D. inextricata species group is defined. A key to separate males and natural history data for each species are provided.

A new species of Austrothaumalea Tonnoir from Australia (Diptera: Thaumaleidae).

Austrothaumalea spiculata sp. nov. is described from Grampians National Park, in southwest Victoria (Australia). It is known only from the type series and is the second species of Thaumaleidae recorded from the Park. Illustrations of the male terminalia, as well as a distribution map, are provided. Phylogenetic affinities are hypothesized and an updated species identification key is offered.