Abstract
A new endemic psyllid genus from the Hawaiian Islands, Stevekenia gen. nov., is described. Two new species, both single island endemics, feed on host plants in the endemic genus Nothocestrum (Solanaceae). Stevekenia nothocestri sp. nov. is found on Nothocestrum longifolium on the island of Oahu and Stevekenia aiea sp. nov. is found on N. peltatum on the island of Kauai. The host plants are montane rainforest species and both are on the IUCN Red List of Threatened Species. In particular, N. peltatum, which is endemic to the island of Kauai, is considered critically endangered, and therefore a similarly endangered status for these host-specific insects is likely. Only a few specimens of each Stevekenia species have been found, suggesting occurrence at low abundance. The host plants survive either as isolated individuals or small fragmented populations, which may already constitute less than the required critical host plant density for the long term survival of this psyllid genus. Unique morphological characters distinguish Stevekenia from other Hawaiian genera, and the placement of this genus within Triozidae is discussed. Mitochondrial DNA barcodes for the new species are provided.
References
Black, S.H. (2005) Species Profile: Manduca blackburni. In: Shepherd, M.D., Vaughan, D.M., & Black, S.H. (Eds), Red List of Pollinator Insects of North America. CD-ROM Version 1. Portland, Oregon: The Xerces Society for Invertebrate Conservation. Available from: http://www.xerces.org/wp-content/uploads/2008/09/manduca_blackburni1.pdf (accessed 28 December 2016)
Boggs, C.L. & Ehrlich, P.R. (2008) Conservation of coevolved insect herbivores and plants. In: Tilmon, K.J. (Ed.), Specialization, Speciation, and Radiation. The Evolutionary Biology of Herbivorous Insects. University of California Press, Berkeley, California, pp. 325–332.
https://doi.org/10.1525/california/9780520251328.003.0023Brodie, G., Pikacha, P. & Tuiwawa, M. (2013) Biodiversity and Conservation in the Pacific Islands: Why Are We Not Succeeding? In: Raven, P.H., Sodhi, N.S. & Gibson, L. (Eds.), Conservation Biology: Voices from the Tropics. John Wiley & Sons, Ltd, Oxford, pp. 181–187.
https://doi.org/10.1002/9781118679838.ch21Burckhardt, D. & Lauterer, P. (1997) A taxonomic reassessment of the triozid genus Bactericera (Hemiptera: Psylloidea). Journal of Natural History, 31, 99–153.
https://doi.org/10.1080/00222939700770081Butler, C.D. & Trumble, J.T. (2012) The potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Triozidae): life history, relationship to plant diseases, and management strategies. Terrestrial Arthropod Reviews, 5, 87–111.
https://doi.org/10.1163/187498312X634266Caldwell, J.S. (1940) New genera and species of jumping plant-lice from the Hawaiian Islands with descriptions of several immature stages (Homoptera: Psyllidae). Proceedings of the Hawaiian Entomological Society, 10, 389–397.
Enderlein, G. (1926) Psyllidologica VIII. Entomologische Mitteilungen, 15, 397–401.
Foerster, A. (1848) Uebersicht der Gattungen und Arten in der Familie der Psylloden. Verhandlungen des Naturhistorischen Vereins der Preussischen Rheinlande, 5, 65–98.
Fonseca, C.R. (2009) The silent mass extinction of insect herbivores in biodiversity hotspots. Conservation Biology, 23, 1507–1515.
https://doi.org/10.1111/j.1523-1739.2009.01327.xFourcade, Y. & Öckinger, E. (2016) Host plant density and patch isolation drive occupancy and abundance at a butterfly's northern range margin. Ecology and Evolution, 2016, 2045–7758.
https://doi.org/10.1002/ece3.2597Furlan, E., Stoklosa, J., Griffiths, J., Gust, N., Ellis, R., Huggins, R.M. & Weeks, A.R. (2012) Small population size and extremely low levels of genetic diversity in island populations of the platypus, Ornithorhynchus anatinus. Ecology and Evolution, 2, 844–857.
https://doi.org/10.1002/ece3.195Hodkinson, I.D. & White, I.M. (1979) Homoptera: Psylloidea. Handbook for the Identification of British Insects, 2 (5a), 1–98. Available from: www.royensoc.co.uk/sites/default/files/old_res_handbooks/Vol02_Part05a.pdf (accessed 7 June 2017)
Hollis, D. (1984) Afrotropical jumping plant lice of the family Triozidae (Homoptera: Psylloidea). Bulletin of the British Museum of Natural History Entomology, 49, 1–102.
Jackson, S.T. & Sax, D.F. (2010) Balancing biodiversity in a changing environment: extinction debt, immigration credit and species turnover. Trends in Ecology and Evolution, 25, 153–60.
https://doi.org/10.1016/j.tree.2009.10.001James, J.E., Lanfear, R. & Eyre-Walker, A. (2016) Molecular evolutionary consequences of island colonization. Genome Biology and Evolution, 8, 1876–1888.
https://doi.org/10.1093/gbe/evw120Kingsford, R.T., Watson, J.E.M., Lundquist, C.J., Venter, O., Hughes, L., Johnson, E.L., Atherton, J., Gawel, M., Keith, D.A., Mackey, B.G., Morley, C., Possingham, H.P., Raynor, B., Recher, H.F. & Wilson, K.A. (2009) Major conservation policy issues for biodiversity in Oceania. Conservation Biology, 23, 834–840.
https://doi.org/10.1111/j.1523-1739.2009.01287.xKirkaldy, G.W. (1902) Hemiptera. Fauna Hawaiiensis, 3, 93–174.
Laukkanen, L., Mutikainen, P., Muola, A. & Leimu, R. (2014) Plant-species diversity correlates with genetic variation of an oligophagous seed predator. PLoS ONE, 9, e94105.
https://doi.org/10.1371/journal.pone.0094105Li, F. (2011) Psyllidomorpha of China (Insecta: Hemiptera). Huayu Nature Book Trade Co.Ltd, Beijing, 1976 pp.
Löw, F. (1879) Zur Systematik der Psylloden. Verhandlungen der Zoologisch-Botanischen Gesellschaft in Wien, 28, 586–610.
Medeiros, A.C., Davenport, C.F. & Chimera C.G. (1998) Auwahi: Ethnobotany of a Hawaiian Dryland Forest. Cooperative National Park Resources Studies Unit, University of Hawaiʻi at Mānoa, Hawaii, 49 pp. Available from: http://www.hear.org/naturalareas/auwahi/ethnobotany_of_auwahi.pdf (accessed: 28 December 2016)
Moir, M.L., Coates, D.J., Kensington, W.J., Barrett, S., Taylor, G.S. (2016) Concordance in evolutionary history of threatened plant and insect populations warrant unified conservation management approaches. Biological Conservation, 198, 135–144. https://doi.org/10.1016/j.biocon.2016.04.012
Moir, M.L., Hughes, L., Vesk, P.A. & Leng, M.C. (2014) Which host-dependent insects are most prone to coextinction under changed climates? Ecology and Evolution, 4, 1295–1312.
https://doi.org/10.1002/ece3.1021Ouvrard, D. (2016) Psyl’list: the world psylloidea database. Available from: http://www.hemiptera-databases.com/psyllist/ (accessed 15 December 2016)
Percy, D.M. (2003a) Legume-feeding psyllids (Hemiptera, Psylloidea) of the Canary Islands and Madeira. Journal of Natural History, 37, 397–461.
https://doi.org/10.1080/713834706Percy, D.M. (2003b) Radiation, diversity, and host-plant interactions among island and continental legume-feeding psyllids. Evolution, 57, 2540–2556.
https://doi.org/10.1111/j.0014-3820.2003.tb01498.xPercy, D.M. (2011) Insect-plant interactions on islands: codiversification of legume-feeding psyllids (Psylloidea) and their Fabaceae hosts. In: Serrano, A.R.M., Borges, P.A.V., Boieiro, M. & Oromí, P. (Eds.), Terrestrial arthropods of Macaronesia—biodiversity, ecology and evolution. Fundação para Ciência e a Tecnologia, Lisbon, pp. 285–308.
Percy, D.M. (2017) Making the most of your host: the Metrosideros-feeding psyllids (Hemiptera, Psylloidea) of the Hawaiian Islands. ZooKeys, 649, 1–163.
https://doi.org/10.3897/zookeys.649.10213Percy, D.M., Crampton-Platt, A., Sveinsson, S., Lemmon, A.R., Moriarty Lemmon, E., Ouvrard, D. & Burckhardt, D. (2017) Resolving the psyllid tree of life: a phylogeny of the superfamily Psylloidea (Hemiptera). [in preparation]
Percy, D.M., Page, R.D.M. & Cronk, Q.C.B. (2004) Plant-insect interactions: double-dating associated insect and plant lineages reveals asynchronous radiations. Systematic Biology, 53, 120–127.
https://doi.org/10.1080/10635150490264996Puton, A. (1876) Notes pour servir à l'étude des Hémiptères. Description d'espèces nouvelles ou peu connues. Annales de la Société entomologique de France, 6, 275–290.
Simon, C., Frati, F., Beckenbach, A., Crespi, B., Liu, H. & Flook, P. (1994) Evolution, weighting, and phylogenetic utility of mitochondrial gene sequences and a compilation of conserved polymerase chain reaction primers. Annals of the Entomological Society of America, 87, 651–701.
https://doi.org/10.1093/aesa/87.6.651Straw, N.A. & Ludlow A.R. (1994) Small-scale dynamics and insect diversity on plants. Oikos, 71, 188–192.
https://doi.org/10.2307/3546188Šulc, K. (1909) Trioza cockerelli n.sp., a novelty from North America, being also of economic importance. Acta Societatis Entomologicae Bohemiae, 6, 102–108.
Swezey, O.H. (1954) Forest Entomology in Hawaii. Special Publication 44. Bernice P. Bishop Museum, Honolulu, 266 pp.
Swofford, D.L. (2003) PAUP*: phylogenetic analysis using parsimony (*and other methods). Version 4. Sinauer, Sunderland, MA.
Syfert, M.M., Serbina, L., Burckhardt, D., Knapp, S. & Percy, D.M. (2017) Emerging new crop pests: ecological modelling and analysis of the South American potato psyllid Russelliana solanicola (Hemiptera: Psylloidea) and its wild relatives. PLoS ONE, 12, e0167764.
https://doi.org/10.1371/journal.pone.0167764Taylor, G.S. & Moir, M.L. (2009) In threat of co-extinction: two new species of Acizzia Heslop-Harrison (Hemiptera: Psyllidae) from vulnerable species of Acacia and Pultenaea. Zootaxa, 2249, 20–32.
Tilman, D., May, R.M., Lehman, C.L. & Nowak, M.A. (1994) Habitat destruction and the extinction debt. Nature, 371, 65–66.
https://doi.org/10.1038/371065a0Timmermans, M.J., Dodsworth, S., Culverwell, C.L., Bocak, L., Ahrens, D., Littlewood, D.T.J., Pons, J. & Vogler, A.P. (2010) Why barcode? High-throughput multiplex sequencing of mitochondrial genomes for molecular systematics. Nucleic Acids Research, 38, e197.
https://doi.org/10.1093/nar/gkq807Triantis, K.A., Borges, P.A.V., Ladle, R.J., Hortal, J., Cardoso, P., Gaspar, C., Dinis, F., Mendonça, E., Silveira, L.M.A., Gabriel, R., Melo, C., Santos, A.M.C., Amorim, I.R., Ribeiro, S.P., Serrano, A.R.M., Quartau, J.A. & Whittaker, R.J. (2010) Extinction debt on oceanic islands. Ecography, 33, 285–294.
https://doi.org/10.1111/j.1600-0587.2010.06203.xTuthill, L.D. (1956) A new genus of Psyllidae from Hawaii (Homoptera). Proceedings of the Hawaiian Entomological Society, 16, 158–161.
Tuthill, L.D. (1959) Los Psyllidae del Perù Central (Insecta: Homoptera). Revista Peruana de Entomologia Agricola, 2, 1–27.
Wagner, W.L., Herbst, D.R. & Lorence, D.H. (2005) Flora of the Hawaiian Islands website. Available from: http://botany.si.edu/pacificislandbiodiversity/hawaiianflora/index.htm (accessed 9 January 2017)
Wang, S., Zhu, W., Gao, X., Li, X., Yan, S., Liu, X., Yang, J., Gao, Z. & Li, Y. (2014) Population size and time since island isolation determine genetic diversity loss in insular frog populations. Molecular Ecology, 23, 637–48.
https://doi.org/10.1111/mec.12634Wood, K.R. (2001a) The distribution and abundance of Nothocestrum peltatum Skottsb. & Nothocestrum longifolium A. Gray on Kaua'i, Hawai'i. Special Report Prepared for the US Fish and Wildlife Service.
Wood, K.R. (2001b) The distribution and abundance of Nothocestrum latifolium A. Gray & N. longifolium A. Gray on Moloka'i, Hawai'i. Special Report Prepared for the US Fish and Wildlife Service.
Wood, K.R. (2012) Possible extinctions, rediscoveries, and new plant records within the Hawaiian Islands. Bishop Museum Occasional Papers, 113, 91–102.
World Conservation Monitoring Centre (1998a) Nothocestrum longifolium. The IUCN Red List of Threatened Species 1998: e.T33577A9794512.
https://doi.org/10.2305/IUCN.UK.1998.RLTS.T33577A9794512.enWorld Conservation Monitoring Centre (1998b) Nothocestrum peltatum. The IUCN Red List of Threatened Species 1998: e.T30947A9594854.
https://doi.org/10.2305/IUCN.UK.1998.RLTS.T30947A9594854.enYang, M.M., Burckhardt, D. & Fang, S.J. (2013) Psylloidea of Taiwan. Volume II. Family Triozidae. National Chung Hsing University, Taichung, 160 pp.
Yuan, N., Comes, H.P., Mao, Y.-R., Qi, X.-S. & Qiu, Y-X. (2012) Genetic effects of recent habitat fragmentation in the Thousand-Island Lake region of southeast China on the distylous herb Hedyotis chrysotricha (Rubiaceae). American Journal of Botany, 99, 1715–1725.
https://doi.org/10.3732/ajb.1200054Zimmerman, E.C. (1948) Homoptera: Sternorhyncha: Superfamily Psylloidea. In: Insects of Hawaii. Vol. V. University of Hawaii Press, Honolulu, pp. 11–38.