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A Key to Fijian Xixuthrus Sspecies 1 Elytra without complete, glabrous, longitudinal stripes (Fig. 5) ... X. terribilis Thomson ­ Elytra with complete, glabrous, longitudinal stripes (Fig. 1)........................................ 2 2 Forebasitarsi only slightly longer than broad (at apex; Fig. 2) X. ganglbaueri Lameere ­ Forebasitarsi at least two times longer than broad (Fig. 4) ................... X. heros (Heer), Published as part of Yanega, Douglas, Olson, David, Shute, Sharon & Komiya, Ziro, 2004, The Xixuthrus species of Fiji (Coleoptera: Cerambycidae: Prioninae), pp. 1-10 in Zootaxa 777 (1) on page 8, DOI: 10.11646/zootaxa.777.1.1, http://zenodo.org/record/5030418

Xixuthrus ganglbaueri Lameere, 1912 Figs. 1–2 Specimens examined: Neotype female (here designated), " Fiji, Viti Levu, Tamavua FSN, 28.v.2003, coll. Salanieta Tawake ", " NEOTYPE Xixuthrus ganglbaueri Lameere, det. D. Yanega 2003" (originally from MAFF; will be permanently deposited in BPBM, as type #16557) [Figs. 1, 2]; 1 female, Fiji, Viti Levu, Nasinu, 05.v.81, coll. Marika Rasekaseka (MAFF); 1 female, same locality, 01.viii.88, coll. A. Vosanibola (MAFF); other specimens known only from photographs. Diagnosis: This species can easily be confused with heros (with which it is sympatric; both species are presently confirmed only from Viti Levu, primarily the SE quadrant of the island), though careful examination reveals that it differs in numerous characters, ultimately uniquely sharing little more than the broad glabrous elytral stripes. The major differences (compare Figs. 2 and 4) include the lack of prickly spicules on the antennal scape, which is instead covered with distinct, shallow punctures; the scape is only gradually and slightly enlarged apically, in distinct contrast to the apically swollen scape in heros and terribilis; much shorter antennae relative to body length; there is a glabrous, impunctate, diamond­shaped area in the center of the pronotum; and, in particular, the forebasitarsi are scarcely longer than broad (the mid and hind basitarsi are similarly proportioned, but the difference between ganglbaueri and the other species is more evident in the foretarsi). Additionally, the posterior portion of the head is not as elongated, nor are the mandibles; the mandibular teeth are much smaller; the frontal groove is rather deeply impressed from the clypeus up to the vertex; the distal tarsomere is relatively shorter; the pronotal surface is more generally shining, with the medial ridges generally weaker but more strongly produced and somewhat tuberculate posteriorly. The general coloration of the pubescence is more grayish, or somewhat silvery, in comparison to the usual coloration of heros, which is more brownish to golden, but this difference is somewhat less evident in more worn specimens. Remarks: The female chosen as the neotype is considered appropriate for two reasons: (1) this is the specimen from which a mesotarsus was removed for sequencing while it was still alive, and it is the genetic voucher for the species, and (2) given Lameere's original claim that the species resembled helleri, and the description of the antennae and foretarsi, the evidence supports that the neotype is in fact the same species that Lameere originally described. The alternative hypothesis, that ganglbaueri was a mislabeled New Guinean species, and there just happens, by coincidence, to be an undiscovered Fijian species which shares several features with it, is far less acceptable. New Guinean specimens which Tippmann identified as ganglbaueri have proven, upon examination (by S.S.), to be helleri. We have seen only a photograph of one male which could definitively be associated with the female, and it also possesses short forebasitarsi, short antennae, strong pronotal ridges, and grayish pubescence (though not clear, it does seem that the photo shows a punctate scape, and central glabrous pronotal spot, but to be cautious we do not use these features in the key below); it is possible that other males may be more difficult to distinguish from male heros, but at least this one specimen is readily separable. We further note that the shorter head, mandibles, and antennae of ganglbaueri are not an artifact of the specimens being smaller than those of heros (i.e., the differences are not due to allometry), even though the average size appears slightly smaller; the neotype female is nearly 9 cm, while the heros female figured is 11 cm, and the differences are independent of the size of heros individuals used for comparison (several of which were in fact smaller). Gene sequencing (performed by David Hawks) leaves no doubt whatsoever that this specimen is not conspecific with X. heros from the same general locality; the number of base pair differences and large number of insertions (54 base pair changes and 49 insertions in ribosomal 28S regions D2 and D5) constitute as substantial a genetic difference as is sometimes seen between different genera in other families of beetles (Hawks & Heraty, in prep.). The numerous genome insertions suggest that ganglbaueri is the more derived taxon, and we expect to find that when terribilis is sequenced, it will prove to be the sister taxon to heros, rather than ganglbaueri., Published as part of Yanega, Douglas, Olson, David, Shute, Sharon & Komiya, Ziro, 2004, The Xixuthrus species of Fiji (Coleoptera: Cerambycidae: Prioninae), pp. 1-10 in Zootaxa 777 (1) on pages 4-6, DOI: 10.11646/zootaxa.777.1.1, http://zenodo.org/record/5030418, {"references":["Lameere, A. (1912) Revision des Prionides. Memoires de la Societe Entomologique de Belgique, 21, 113 - 188."]}

Xixuthrus heros (Heer, 1868) Figs. 3­4 Specimens examined: 1 male, " Viti Lefu " (BMNH); 1 male, Fiji, 1962 N.W. Simmonds (BMNH); 1 male, 1 female, Fiji, Suva, 15.ix.1932, W. Simmonds (BMNH); 1 male, no data (BMNH); 1 male, Fiji, 1953 H. Simmonds (BMNH); 1 male, Fiji, 1905, Fry Coll. (BMNH); 1 male, Fiji, Viti Levu, Lami, 5.vii.1986, coll. Tevita Tuimereke (MAFF); 1 male, Fiji, Viti Levu, Naivikinikini village, 178°24'E, 18°06'S, 30.xii. 2003, 50m, coll. Isikeli Delaivuna (MAFF) [Fig. 3]; 1 female, Fiji, Viti Levu, Colo­i­Suva Forest Station 22.v.1996 (MAFF) [Fig. 4]; 1 male, " Fidgi " (Z. Komiya); 1 female " Fidsdsi, Tassein Viti Levu " (Z. Komiya); 1 male, Viti Levu, Navai Mill, nr. Nandarivatu, 13.ix.1938, 2,400ft. (BPBM). Diagnosis: This species is easily distinguished from the other Fijian species as the elytra have broad glabrous stripes and the flagellomeres (except the distal pair) bear numerous prominent spinules in the male (Fig. 3). Females (Fig. 4) are further distinguished from ganglbaueri by numerous structural features, as mentioned above, including the longer forebasitarsi, apically swollen and spiculate scape, less produced medial pronotal ridges, and longer antennae. A few specimens have the frontal groove nearly as deep as in ganglbaueri, so this feature seems of limited diagnostic value, though we have seen none with elytral pubescence of exactly the same color. Structurally, both sexes of heros are nearly identical to terribilis, though the latter typically have a slightly more elongated vertex (Figs. 5 & 6) and lack elytral stripes. These latter two species share not only the male antennal spinules and long necks and mandibles, but also have the same pronotal and prosternal sculpture, and forebasitarsal proportions, in both sexes. Remarks: We consider it likely that heros and terribilis are very close sister taxa, and they may or may not be allopatric; anecdotal reports indicate that heros may occur on Vanua Levu (not on Taveuni, contrary to Ryan, 2000), where terribilis has also been found, and the holotype of heyrovskyi is labeled as having come from Viti Levu, though no other specimens have ever been recorded from the island. As mentioned earlier, the holotype of heros is missing, but the identity of the species is not in doubt, so a neotype cannot be designated (following ICZN Article 75.2). A male from Fiji, Viti Levu, Lami, collected in 2004 (not listed above), was selected as a genetic voucher for this species. Komiya (2000) has an excellent habitus photo of a male heros., Published as part of Yanega, Douglas, Olson, David, Shute, Sharon & Komiya, Ziro, 2004, The Xixuthrus species of Fiji (Coleoptera: Cerambycidae: Prioninae), pp. 1-10 in Zootaxa 777 (1) on pages 6-7, DOI: 10.11646/zootaxa.777.1.1, http://zenodo.org/record/5030418, {"references":["Heer, O. (1868) Plate 1, figure 3. In: Graeffe, E. (Ed.) Reise im Innern der Insel Viti-Levu. Zurcher & Furrer, Zurich, p. 47.","Ryan, P. (2000) Fiji's Natural Heritage. Exisle Publishing Ltd., Auckland, 288 pp.","Komiya, Z. (2000) Notes on Xixuthrus heros and its allied species with description of a new species (Coleoptera, Cerambycidae, Prioninae). Gekkan-Mushi, 354, 2 - 7."]}

Yanega, Douglas, Olson, David, Shute, Sharon, Komiya, Ziro (2004): The Xixuthrus species of Fiji (Coleoptera: Cerambycidae: Prioninae). Zootaxa 777 (1): 1-10, DOI: 10.11646/zootaxa.777.1.1, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.777.1.1

Xixuthrus terribilis Thomson, 1877 Figs. 5­6 Xixuthrus heyrovskyi Tippman, 1945 NEW SYNONYMY Specimens examined: Holotype male X. terribilis, "Ins. Fidgi" (MNHN; labeled " TYPE ") [Fig. 5]; holotype male X. heyrovskyi, " Insel Viti Levu Fidschi," coll. Dr. Knoth (USNM; labeled " TYPE ") [Fig. 6]; 2 males, Fiji, Taveuni, Silvester Evans (BMNH); 1 male, same data but 1.1925 (BMNH); 1 female, Taveuni, 14.vi.1925, Dr. H.S.Evans (BMNH); 1 female, Taveuni, "Qacovilo" (? spelling obscured by pin hole), 26.v.1925, Dr. H.S. Evans (BMNH); 1 male, 2 females, no data (BMNH); 1 male, Vanua Levu, Caukadrove Province, Natewa Peninsula, Buca, Buca Bay, 24.vii.2003, 179°32' S, 16°39' E, 50m, collector Tomasi Mateavula (MAFF); 1 male, 1 female, Somo Somo, Taveuni, 6.ii.1990, George Bennett Coll. (Z. Komiya) Diagnosis: For diagnostic features, see entry above under heros. Remarks: The holotypes of both X. terribilis and X. heyrovskyi were examined, and are unquestionably conspecific. The holotype of terribilis is a relatively small specimen, measuring 99 mm, and differs from typical male specimens (including the holotype of heyrovskyi) only in those features which show distinct allometry. Several specimens from Taveuni (in George Bennett's private collection in Suva, Fiji) were also briefly examined (by D.Y.) in addition to those listed above. Note that the pubescence along the elytral costae may occasionally show some wear, creating very narrow, obscurely glabrous stripes. Aside from the holotype of X. heyrovskyi, there are no confirmed records of this species from any islands other than Taveuni and Vanua Levu, despite anecdotal claims of its presence on Viti Levu, and unless new specimens are found there, we consider it most likely that the heyrovskyi type is mislabeled. It is probable that Lameere did not have a specimen of genuine heros when he placed terribilis into synonymy with it; especially suspicious is that he placed considerable emphasis on the broad elytral stripes of ganglbaueri and helleri when discussing their resemblance, when heros shares these stripes, implying that perhaps his putative heros specimen did not have stripes (i.e., that it was actually a specimen of terribilis). Nonetheless, we are not aware of any specimens of terribilis (other than the holotype itself) old enough to have been examined by Lameere. Komiya (2000) has an excellent habitus photo of a male terribilis (figured as heyrovskyi)., Published as part of Yanega, Douglas, Olson, David, Shute, Sharon & Komiya, Ziro, 2004, The Xixuthrus species of Fiji (Coleoptera: Cerambycidae: Prioninae), pp. 1-10 in Zootaxa 777 (1) on page 7, DOI: 10.11646/zootaxa.777.1.1, http://zenodo.org/record/5030418, {"references":["Thomson, J. (1877) Typi Cerambycidarum, Musei Thomsoniani. Revue et Magasin de Zoologie (3 rd Series), 5, 249 - 279.","Komiya, Z. (2000) Notes on Xixuthrus heros and its allied species with description of a new species (Coleoptera, Cerambycidae, Prioninae). Gekkan-Mushi, 354, 2 - 7."]}