Stick Insect Genus Research Articles

Evolution of alternative reproductive systems in Bacillus stick insects.

Reproduction is a key feature of all organisms, yet the way in which it is achieved varies greatly across the tree of life. One striking example of this variation is the stick insect genus Bacillus, in which five different reproductive modes have been described: sex, facultative and obligate parthenogenesis, and two highly unusual reproductive modes: hybridogenesis and androgenesis. Under hybridogenesis, the entire genome from the paternal species is eliminated and replaced each generation by mating with the corresponding species. Under androgenesis, an egg is fertilized, but the developing diploid offspring bear two paternal genomes and no maternal genome, as a consequence of unknown mechanisms. Here, we reevaluate the previous descriptions of Bacillus lineages and the proposed F1 hybrid ancestries of the hybridogenetic and obligately parthenogenetic lineages (based on allozymes and karyotypes) from Sicily, where all these reproductive modes are found. We generate a chromosome-level genome assembly for a facultative parthenogenetic species (B. rossius) and combine extensive field sampling with RADseq and mtDNA data. We identify and genetically corroborate all previously described species and confirm the ancestry of hybrid lineages. All hybrid lineages have fully retained their F1 hybrid constitution throughout the genome, indicating that the elimination of the paternal genome in hybridogens is always complete and that obligate parthenogenesis in Bacillus hybrid species is not associated with an erosion of heterozygosity as known in other hybrid asexuals. Our results provide a stepping stone toward understanding the transitions between reproductive modes and the proximate mechanisms of genome elimination.

The only species of Calvisia (Phasmatodea, Necrosciinae) from China, with a new synonymy and additional descriptions.

Calvisia is a colorful winged stick insect genus consisting of 6 subgenera and 44 species widely distributed in temperate and tropical Asia. C. medogensis syn. nov. was discovered in Mdog, Xizang (Tibet), China and is so far the only species recorded from China. We here propose that C. medogensis syn. nov. is a synonym of C. fuscoalata after checking type specimens of both species. New materials studied are deposited in Yunnan Agricultural University, China (YNAU).

Mindanao broken stick insect: a new species and first country record of the genus Baculofractum Zompro, 1995 (Phasmatodea: Lonchodidae: Lonchodinae: Lonchodini) from the Philippines

Baculofractum Zompro 1995 is a genus of stick insects in the family Lonchodidae, subfamily Lonchodinae represented by three species: B. insigne, B. shelfordi, and B. williemsei, distributed in Indonesia and Malaysia. This paper reports the discovery of a new species of Baculofractum from Mt. Malimumu, Pantaron Range, Bukidnon which also represents the first record of the genus in the Philippines. The new species can be distinguished by the absence of four tubercles at the back of the head’s median ridges and its distinctly elongated operculum exceeding the end of the abdomen.

Revision of the Neotropical stick insect genus Ocnophila (Phasmatodea: Diapheromeridae) with a new species from Colombia.

The genus Ocnophila Brunner, 1907 is here redescribed with an emended diagnosis, containing three valid species from Venezuela and Colombia: Ocnophila integra Brunner, 1907 with Ocnophila signatior Brunner, 1907 syn. nov. as a new junior synonym, Ocnophila iphicla (Westwood, 1859) and Ocnophila serrata sp. nov. In addition to the description of the new species we redescribe O. integra and O. iphicla, also providing a description of the male genitalia for O. integra. For the other species previously contained in the genus, we synonymize Ocnophila brevifemur Brunner, 1907 syn. nov. and Ocnophila armata Brunner, 1907 syn. nov. under Pygirhynchus bispinosus (Redtenbacher, 1906), Ocnophila inaequalis Brunner, 1907 syn. nov. under Libethra venezuelica Brunner, 1907, and transfer the remaining species to other genera, resulting in the following new combinations: Agamemnon illegitimus (Brunner, 1907) comb. nov., A. poeyi (Bolívar, 1888) comb. nov., Canuleius nattereri (Brunner, 1907) comb. nov., C. pedestris (Brunner, 1907) comb. nov., Dyme acanthonota (Günther, 1930) comb. nov., D. borellii (Giglio-Tos, 1898) comb. nov., D. ramulus (Giglio-Tos, 1898) comb. nov., Exocnophila cornuta (Brunner, 1907) comb. nov., E. tuberculata (Brunner, 1907) comb. nov., Litosermyle inconspicua (Brunner, 1907) comb. nov., Lit. nana (Shelford, 1913) comb. nov., Lit. riveti (Shelford, 1913) comb. nov., Lit. submutica (Brunner, 1907) comb. nov., Libethra aculeata (Brunner, 1907) comb. nov., Libethroidea willemsei (Günther, 1935) comb. nov., Pygirhynchus fortior (Brunner, 1907) comb. nov., P. oryx (Westwood, 1859) comb. nov., P. scops (Kaup, 1871) comb. nov., Pseudosermyle meditans (Brunner, 1907) comb. nov., Sermyle aurita (Rehn, 1905) comb. nov., and S. ciliata (Brunner, 1907) comb. nov. Furthermore, Pygirhynchus carioca Piza, 1944 syn. nov. is synonymized under P. fortior comb. nov. We provide a description of the male and egg of Litosermyle Hebard, 1919, previously known only from females, through the illustration and redescription of Lit. inconspicua (Brunner, 1907) comb. nov. Finally, we include Dubiophasma Zompro, 2001, Exocnophila Zompro, 2001, Litosermyle, Ocnophila and Parocnophila Zompro, 1998 in Oreophoetini.

Further study on the Oriental stick insect genus Paragongylopus Chen & He, 1997, with additional descriptions and one newly recorded species from China (Phasmatodea; Bacillidae; Gratidiini)

The oriental stick insect Paragongylopus Chen & He, 1997 is a small and poorly known genus, including 9 taxa distributed in China, Thailand and Vietnam. The male and egg of most species in this genus are still unknown. In this paper, two subgenera are re-defined with three new combinations: P. (Planoparagongylopus) brevicornis (Ho, 2019) comb. nov., P. (Planoparagongylopus) obtusidentatus (Ho, 2019) comb. nov., P. (Planoparagongylopus) plaumanni (Zompro, 2000) comb. nov. The male of P. (Paragongylopus) sinensis pingbianensis and the male and egg of P. (Planoaragongylopus) obtusidentatus comb. nov. are described for the first time. Photos of P. (Paragongylopus) sinensis sinensis holotype are given with a remark of its identification with another subspecies. P. (Planoparagongylopus) abramovi is firstly recorded from Yunnan Province of China, and it documents that all species of this genus are distributed in China. A key to identifying two subgenera and a distribution map of this genus from Yunnan and the surrounding area are provided as well.

Revision of the Chinese species of Andropromachus Carl, 1913 (Phasmatodea, Lonchodidae, Necrosciinae).

A new species Andropromachus ynau sp. nov.. is described and the Chinese species of the moss-like stick insect genus Andropromachus are reviewed. An updated key to the known species of this genus is provided. Types of the new species are deposited in Yunnan Agricultural University (YNAU).

New species of Andropromachus (Phasmatodea: Lonchodidae: Necrosciinae: Necrosciini) from Yunnan Province, China.

BackgroundThe genus Andropromachus (Lonchodidae: Necrosciinae: Necrosciini) is a small genus of stick insects including four species with a distribution in northern Vietnam and south-western China.New informationA new species of stick insects Andropromachusgulinqingensis sp. n. is described from Yunnan Province of China. Diagnostic characters of the new species are illustrated and an identification key to male and female Andropromachus is provided along with a checklist for all described species.

Integrative taxonomy of the stick insect genus

Austrocarausius Brock, 2000 is a stick insect (Phasmatodea: Lonchodidae) genus containing two species restricted to the tropical rainforests of northern Queensland. Recent specimen collections between the two species’ type localities, Lizard Island and Rockhampton, have suggested that Austrocarausius might represent more than the two nominal species. Here, we apply morphological and molecular analyses to revise the taxonomy of this genus. Using both field-collected and historic museum samples, we developed morphological species hypotheses and descriptions. Genetic sequencing of mitochondrial COI and 16S were undertaken for species delimitation and phylogenetic analysis, including an estimate of the evolutionary timescale of the genus. Based on these results, we propose nine new Austrocarausius species, increasing the number of species in the genus to eleven: A. nigropunctatus (Kirby, 1896), A. mercurius (Stål, 1877), A. coronatus sp. nov., A. decorus sp. nov., A. eirmosus sp. nov., A. gasterbulla sp. nov., A. tuberosus sp. nov., A. macropunctatus sp. nov., A. truncatus sp. nov. A. waiben sp. nov. and A. walkeri sp. nov. Our results suggest Austrocarausius species diversified over the last c. 25–70 Ma, resulting in the now endemic distributions in the tropical rainforests of the central and northern Queensland coasts. This is the first integrative systematic study of an Australian phasmid genus, combining morphological, molecular and biogeographical methods. Additional species of Austrocarausius likely remain undescribed as can be inferred from methodical sampling of rainforest patches along the Queensland coast.

Sexual dimorphism divergence between sister species is associated with a switch in habitat use and mating system in thorny devil stick insects

The habitat and resource use of females critically affects their pattern of distribution and consequently their monoposibility by males and the mating system of a species. Shifts in habitat use are therefore likely to be associated with changes in mating system and sexual selection acting on males’ phenotypes, consequently affecting patterns of sexual dimorphism. Although sexual dimorphism is often correlated with shifts in habitat use at the macroevolutionary scale, the underlying microevolutionary processes involved are typically unclear. Here, we used the New Guinean stick insect genus Eurycantha to investigate how changes in habitat use and mating system were associated with a change in sexual dimorphism seen specifically in the thorny devil stick insects (Eurycantha calcarata and Eurycantha horrida). Male thorny devils display sexually dimorphic and enlarged hindlegs endowed with a sharp spine. Sexual size dimorphism is also very reduced in these species relative to other phasmids. Using field observations, morphological measurements and radiotelemetry, we investigated changes in mating system associated with the reduction of sexual dimorphism and tested predictions from the hypothesis that sexual selection drove the evolution of this unusual male morphology. We found that thorny devils switched from solitary roosting in the canopy during the day to communal roosting inside cavities of a few host trees, shifting the distribution of females from scattered to clumped. Male thorny devils used their large hindlegs to fight with rivals for positions on the tree close to cavities containing females, and larger males were associated with cavities containing relatively more females. In contrast, the sister species, Eurycantha insularis, displays relatively small and unarmoured males (ancestral state). Adult female E. insularis were always scattered in the canopy, and this species displayed a scramble competition mating system typical of other phasmids, where mobility, rather than fighting ability, is probably critical to males’ reproductive success. Overall, our study illustrates how a drastic change in sexual dimorphism can be associated with a switch from solitary to communal roosting and from a scramble competition to a defense-based polygyny mating system.

The puzzling taxonomic rank of Pijnackeria hispanica, a chimerical hybrid androgen (Insecta, Phasmida)

The stick-insect genus Pijnackeria includes four diploid bisexual and two polyploid (3n, 4n) parthenogenetic species. Earlier analyses of the tetraploid parthenogen P. hispanica using mitochondrial markers allowed tracing its maternal ancestry to Pijnackeria originis, while no maternal nuclear contribution was found, thus suggesting an androgenetic and hybrid origin. The recently described Pijnackeria recondita—showing, among other features, a specific antennal structure linking it to the tetraploid parthenogen—prompted us to check whether the new species could be the unknown paternal ancestor of P. hispanica. In this work, we use karyology and molecular analysis of the mitochondrial gene cytochrome c oxidase subunit 2 (cox2) and the nuclear gene elongation factor 1 subunit α (ef1-α) to investigate the origin of such a complex tetraploid hybrid parthenogen. The molecular analysis supported P. recondita as being a paternal ancestor of P. hispanica, but also suggested that two more fathering species have to be taken into account: P. barbarae and the unknown paternal ancestor of the triploid hybrid P. masettii. Therefore, P. hispanica is apparently a polyphyletic chimeric androgen, which we propose to indicate as an androgenetic complex. Our data also revealed that P. hispanica is between 1.96 Myr and 3.31 Myr old, making it the oldest parthenogenetic taxon discovered among insects.

Contributions to the knowledge of Canuleius Stål (Phasmatodea: Heteronemiidae): taxonomy, morphology and notes on the biology of two species.

We present new information on the poorly known genus of stick insects, Canuleius Stål, 1875, with redescriptions of two Brazilian species, Canuleius grandis Toledo Piza, 1936 and Canuleius sanguinolentus (Brunner von Wattenwyl, 1907) comb. nov., the latter herein transferred from Bacteria Berthold, 1827. Type material of both species was examined, as well as additional specimens recently collected and deposited at the Museu de Zoologia da Universidade de São Paulo (MZUSP). The types of two other species in the genus, Canuleius affinis Toledo Piza, 1936 and Canuleius brevipes Toledo Piza, 1936, were also examined and both species are herein synonymised under C. grandis (syn. nov.). The study includes the first descriptions of the male of C. grandis, the female of C. sanguinolentus and the eggs of both species, which are the first descriptions of eggs of Canuleius. Some notes are presented on the biology of both species, including the first observations of mating and oviposition in Heteronemiidae. Taxonomic aspects of Canuleius are discussed.

Description of the female and egg of Phantasca phantasma (Westwood, 1859) (Phasmatodea: Diapheromeridae: Diapheromerinae).

The neotropical genus of stick insects, Phantasca Redtenbacher, 1906, was recently revised by Hennemann et al. (2018). However, the females and eggs of several species remain unknown, including all five species recorded from Brazil. The female and egg of Phantasca phantasma (Westwood, 1859) are here described for the first time, based on material available at the Museu de Zoologia da Universidade de São Paulo, Brazil (MZSP). A set of measurements of males is also given, in addition to the measurements of the holotype presented in Hennemann et al. (2018). This complement to the description of P. phantasma is particularly important because it is the type species of the genus (designated by Zompro, 2001), therefore providing additional grounds for future taxonomic decisions involving Phantasca.

Species delimitation in the crypsis‐defended and polymorphic stick insects of the genus Libethra (Phasmatodea, Diapheromeridae)

Crypsis is a widespread defensive mechanism for prey ambushed by visually oriented predators. One well‐documented consequence of this interaction is the formation of search images by the predator that leads to the coexistence of multiple morphs in the prey population. Libethra is a genus of stick insects whose ornamentation and coloration are decidedly protective and exhibit exuberant intraspecific variation. Despite this fact, these traits have been extensively used to support the boundaries between the species it includes. This is the case in the north Andean species Libethra rabdota and Libethra rabdotula, delimited on the basis of a specific arrangement of ornamental characters. To state whether such taxonomical practice is meaningful and convenient, we evaluated the grouping of specimens of both species by means of the independent inference of phylogenies obtained with mitochondrial DNA sequences and ootaxonomy. This article synonymizes L. rabdota and L. rabdotula, redescribes the adults and describes the egg of the species. Additionally, we demonstrate that the characters related to crypsis used for the diagnosis of L. rabdota are not exclusive to this species by describing Libethra rioblanco sp. n. and Libethra ucumariensis sp. n. Our findings suggest that this genus requires extensive revision, but also provide support for the usage of different tools that might produce more accurate and stable classification. Evolutionary scenarios for both the extreme morphological variation and possible homoplastic state of camouflage‐related traits are discussed herein.

Brockphasma spinifemoralis gen. et spec. nov.: a new phasmid genus and new species of Neohiraseini (Phasmida: Necrosciinae) from Vietnam.

A new genus of stick insects, Brockphasma Ho gen. nov., with the type-species, Brockphasma spinifemoralis Ho, Liu, Bresseel & Constant spec. nov., is described and illustrated from Vietnam. Both sexes, the egg and the first instar nymph are described and figured. Data on the habitat and natural foodplants are provided. Brockphasma Ho gen. nov. is differentiated from other genera in Neohiraseini by spinose occiput, anterior region of mesonotum with a spinose hump and spinose anterodorsal and posterodorsal carinae of femora. A key to the genera of Neohiraseini from Vietnam is given.

Divergent transcriptional responses to low temperature among populations of alpine and lowland species of New Zealand stick insects (Micrarchus).

In widespread and genetically structured populations, temperature variation may lead to among-population differentiation of thermal biology. The New Zealand stick insect genus Micrarchus contains four species that inhabit different thermal environments, two of which are geographically widespread. RNA-Seq and quantitative PCR were used to investigate the transcriptional responses to cold shock among lowland and alpine species to identify cold-responsive transcripts that differ between the species and to determine whether there is intraspecific geographical variation in gene expression. We also used mitochondrial DNA, nuclear 28S ribosomal DNA and transcriptome-wide SNPs to determine phylogeographic structure and the potential for differences in genetic backgrounds to contribute to variation in gene expression. RNA-Seq identified 2160 unigenes that were differentially expressed as a result of low-temperature exposure across three populations from two species (M. hystriculeus and M. nov. sp. 2), with a majority (68% ± 20%) being population specific. This extensive geographical variation is consistent across years and is likely a result of background genetic differences among populations caused by genetic drift and possibly local adaptation. Responses to cold shock shared among alpine M. nov. sp. 2 populations included the enrichment of cuticular structure-associated transcripts, suggesting that cuticle modification may have accompanied colonization of low-temperature alpine environments and the development of a more cold-hardy phenotype.

Random DNA libraries from three species of the stick insect genus Bacillus (Insecta: Phasmida): repetitive DNA characterization and first observation of polyneopteran MITEs

The repetitive DNA content of the stick insect species Bacillus rossius (facultative parthenogenetic), Bacillus grandii (gonochoric), and Bacillus atticus (obligate parthenogenetic) was analyzed through the survey of random genomic libraries roughly corresponding to 0.006% of the genome. By repeat masking, 19 families of transposable elements were identified (two LTR and six non-LTR retrotransposons; 11 DNA transposons). Moreover, a de novo analysis revealed, among the three libraries, the first MITE family observed in polyneopteran genomes. On the whole, transposable element abundance represented 23.3% of the genome in B. rossius, 22.9% in B. atticus, and 18% in B. grandii. Tandem repeat content in the three libraries is much lower: 1.32%, 0.64%, and 1.86% in B. rossius, B. grandii, and B. atticus, respectively. Microsatellites are the most abundant in all species. Minisatellites were only found in B. rossius and B. atticus, and five monomers belonging to the Bag320 satellite family were detected in B. atticus. Assuming the survey provides adequate representation of the relative genome, the obligate parthenogenetic species (B. atticus), compared with the other two species analyzed, does not show a lower transposable element content, as expected from some theoretical and empirical studies.

Description and ecology of new Pijnackeria stick insects: four bisexual species and a triploid parthenogen with their phyletic relationships

Recently, the Iberian stick insect genus Pijnackeria has been erected by splitting Leptynia Pantel on the basis of several distinguishing features. In addition to Pijnackeria hispanica, the tetraploid all-female type species, molecular, karyological and SEM investigations led to the recognition of four bisexual and one triploid unisexual new species. Bisexuals' karyotypes (2n = 37/38) differ for minute traits and the haploid set is repeated, with few differences, three or four times in the polyploids that appeared to be of hybrid origin. Diagnostic morphological traits were found among body size parameters, antennal articles, male cerci, ovipositor valve and egg chorionic features. All species commonly feed on the broom Sarothamnus scoparius, but habitat disturbance appeared to induce food plant shifts. Moreover, trends from bisexuality to unisexuality through spanandry, probably related to habitat disruption, have been witnessed. The diploid species (Pijnackeria lucianae, Pijnackeria barbarae, Pijnackeria lelongi and Pijnackeria originis) have small ranges, while the polyploid hybrids (Pijnackeria masettii and P. hispanica) spread through Spain and Southern France, featuring a clear geographic parthenogenesis scenario, by colonizing wide areas and likely displacing their ancestors, or even leading them to extinction. Cyclic climatic changes and natural or anthropic habitat fragmentation may have been also of relevance in shaping present-day distribution.

Revision of the stick insect genus Leptynia: description of new taxa, speciation mechanism and phylogeography

Leptynia specimens were analyzed by karyotype analysis, mitochondrial gene sequencing and SEM of bodies and eggs. Here we describe a new species, Leptynia annaepaulae, and three subspecies of L. attenuata Pantel (L. attenuata attenuata, L. attenuata iberica, L. attenuata algarvica). The phylogeny of the genus Leptynia is congruent with a karyotype trend toward a reduction of chromosome number and the shift from the shared XX/X0 sex chromosome formula to the unusual XX/XY one. Chromosome repatterning appears to occur ahead of genetic differentiation, following a chromosome model of cladogenesis. Chromosome and genetic differentiation, in turn, appears to precede morphological distinction, thus realizing a condition of incipient species for most of the Leptynia taxa. Actually, morphological analyses revealed that, only rarely clear cut differences exist among and between taxa, while, more often, just trends in the differentiating traits occur, since the investigated characters generally suffer from some overlapping: In this study, only the 10th:9th ratio value and the subanal vomer appear to be diagnostic for L. annaepaulae against all other Leptynia taxa. As a consequence, the subanal vomer as well as cercus tooth features with egg chorion traits are not sharply diagnostic for the remaining co-generic taxa; however, comparisons are quite helpful in reducing uncertainties. A likely phylogeographic scenario for the genus supports that Leptynia ancestors spread from Northern Africa into Southern Spain where an ancestral taxon originated L. annaepaulae (2n = 40/39, XX/X0, with 2 large dibrachial pairs). Later on, a northbound colonization, should have originated L. caprai (2n = 40/39, XX/X0, all acrocentrics), from which L. montana (2n = 38, XX/X0) and L. attenuata (2n = 36, XY/XX) originated; supporting instances of chromosome repatterning have been actually observed. In this connection we like to stress that, particularly in stick insects, androgenesis has been a preferential pathway to quickly make homozygous those odd chromosome rearrangements likely responsible for low fitness in the heterozygotes.

Revision of the Iberian stick insect genus Leptynia Pantel and description of the new genus Pijnackeria

The Iberian phasmid species Leptynia attenuata and L. hispanica (Pantel, 1890) are actually species‐complexes, each embodying a few specific taxa. Morphological, karyological and molecular investigations concordantly revealed that considerable differences exist between the two complexes, each representing a monophyletic group. Significant differentiating body traits are: the presence in the “attenuata” males of a well‐developed subanal vomer, which is lacking in those of the hispanica‐complex; the sharply pointed abdomen tip in the “hispanica” females, quite different from the rounded abdomen ending of the attenuata‐complex females. Also the egg structure and SEM chorionic pattern differ neatly. Karyotypes of the “attenuata” taxa mainly differ by chromosome repatternings entraining number reductions, while those of the hispanica‐complex maintain the same chromosome number in sexual taxa and add similar haploid sets in polyploid parthenogens. Also molecular investigations neatly separate the complexes and support specific differentiations of taxa within each complex; therefore, a splitting of the genus Leptynia is felt necessary. Caudell wrongly reported the designation by Pantel of L. hispanica as the type species of the genus, while Kirby validly indicated Leptynia attenuata as the type species; therefore, the subsequent Leptyniella proposition for the Leptynia attenuata complex by Bolìvar, is not valid either. Thus in the genus splitting, the Leptynia designation must be maintained to the “attenuata” complex, while the new name Pijnackeria is here given to the former “hispanica” taxa. This splitting is in full accordance with the seminal description by Pantel for the occurrence of the subanal vomer in the L. attenuata males and the presence of the pointed female abdomen in “hispanica” taxa, plainly settling a rather confusing nomenclatural situation. It also significantly updates the Iberian phasmid systematics. The formal description of taxa belonging to the reshaped Leptynia and to the new genus Pijnackeria will be dealt with in papers to follow.

Are you my mother? Phylogenetic analysis reveals orphan hybrid stick insect genus is part of a monophyletic New Zealand clade

The hybrid stick insect genus Acanthoxyla Uvarov 1944 is unusual for an obligate parthenogen, in the extreme morphological diversity it exhibits that has led to eight species being recognised. The New Zealand sexual species Clitarchus hookeri [White, A. 1846. The zoology of the Voyage of H.M.S. Erebus and Terror. In: 1 Insects of New Zealand. E.W. Janson, London.] is the putative parental species in the hybridization that gave rise to the hybrid lineage Acanthoxyla. In an effort to identify the maternal ancestor of Acanthoxyla we sequenced nuclear 28S rDNA and/or mtDNA COI & COII of all nine endemic New Zealand stick insect genera, representing 17 of the 22 described species. We also sequenced 28S from eight non-New Zealand stick insects to supplement published 28S sequence data that provided a taxonomically and geographically broad sampling of the phasmids. We applied a novel search algorithm (SeqSSi = Sequence Similarity Sieve) to assist in selection of outgroup taxa for phylogenetic analysis prior to alignment. Phylogenetic reconstructions resolved an exclusively New Zealand clade to which the maternal lineage of Acanthoxyla belonged, but did not support existing higher level taxonomy of stick insects. We did not find a sexual maternal species for Acanthoxyla but phylogenetic relationships indicate that this species lived in New Zealand and could be classified among the New Zealand Phasmatinae. Among the available taxa, the nearest evolutionary neighbours to the New Zealand phasmid fauna as a whole were predominantly from the New Zealand region (Fiji, Australia, New Guinea, New Caledonia and South America). As it appears to be an orphan, it is interesting to speculate that a combination of parthenogenetic reproduction and/or hybrid vigour in Acanthoxyla may have contributed to the extinction of its mother.