Memoirs of the Museum of Victoria 56(2):659-666 (1997) 28 February 1997 https://doi.org/10.24199/j.mmv.1997.56.67 BIODIVERSITY OF NEW ZEALAND BEETLES (INSECTA, COLEOPTERA) J. KLIMASZEWSK.I Manaaki Whenua — Landcare Research, Private Bag 92170, Auckland, New Zealand Present address: BC Research. 3650 Weshrook Mall, Vancouver V6S SLS, Canada Abstract Klimaszewski, J., 1 997. Biodiversity of New Zealand beetles (Insecta: Coleoptera). Memoirs of the Museum of Victoria 56(2): 659-666. Approximately 5235 species are described for New Zealand, including 354 introduced. They belong to 82 families in two suborders, Adephaga and Polyphaga. The New Zealand beetle fauna is distinguished by the absence of many major lineages, a high level of endem- ism. which in many groups is over 90% at the specific level and over 43% at the generic level (e.g.. Staphylinidae), and the radiation of many groups of genera and species. The origins of New Zealand's beetle fauna are still poorly understood. They are likely to be varied, includ- ing Gondwanan elements and elements which arrived here by short and long-distance dispersal recently and in the remote past. The size of the New Zealand beetle fauna is con- sistent with species number/land area relationships in other areas around the world. Introduction Zealand beetles is that of Kuschel (1990), in the suburb of Lynfield, Auckland, in which 982 The beetles are the largest order of organisms, beetle species were recorded in a diverse veg- with over 350 000 described species world- etation including remnant forest, pastureland, wide. and suburban garden. There are approximately 4881 described Factors responsible for the diversity and native and 354 introduced species of beetles in nature of the present-day New Zealand beetle New Zealand (Appendix 1), representing c. 1094 fauna are: genera in 82 families (Klimaszewski and Watt, 1. Gondwanan origin of some of our biota; in press). The total number of species is esti- 2. approximately 80 million years of geographic mated at around 10 000 to 10 500 (Watt, 1976: isolation of New Zealand, which has resulted Kuschel, 1990). In comparison, the vascular in a high level of generic endemism and plant flora includes about 2500 species, and the approximately 90% endemism at the specific terrestrial vertebrate fauna about 350 species level; (Watt, 1976). Watt (1976) estimated at 20 000 3. changing climate, changing shorelines (Oligo- of described and undescribed the number cene bottleneck) (Cooper and Millner, 1993; species of terrestrial and freshwater Arthropoda Cooper and Cooper, 1 995), orogenies, glacia- probably occurring in New Zealand. tion, and volcanic activity; and Zealand beetles belong to two suborders, New 4. absence of terrestrial mammals and other Polyphaga. Archostemata and Adephaga and animals and plants which have dominated in Australia, are absent Myxophaga, present ecosystems elsewhere in the world. from New Zealand. Four families (Archeocryp- and Trogidae) are ticidae, Gyrinidae, Lycidae, Origin of New Zealand beetles present only as introduced species. One, Chalco- Zealand region its ancestral biota dryidae, is endemic. Eleven families are rep- The New and resented by more than 100 species: Curculioni- originated in the fragmentation of part of an )" including Pselaphinae ancient supercontinent, Gondwana (Cooper and dae ( 1 32 1 Staphylinidae 1 and Cooper, 1 In the (1021), Carabidae (445), Colydiidae (196), Cer- Millner, 993; Cooper 995). 80-85 (million years ambycidae (188), Scydmaenidae (165), Chry- late Cretaceous c. mya Elateridae ago), the New Zealand region had separated somelidae ( 1 56), Scarabaeidae (144), Scirtidae ( 1 25). from the remainder of Gondwana through (135), Tenebrionidae ( 1 34), and broadening Some smaller families — Byrrhidae, Cleridae, active sea-floor spreading and of the Tasman Sea. The New Zealand region with its Hvdraenidae, Corticariidae ( = Latridiidae), has been geographically isolated for Le'iodidae, Melandryidae, and Trogossitidae — biota thus approximately the last 80 mya, and during this are also well represented in New Zealand. The most comprehensive local survey of New period has undergone an active tectonic and 659 660 .1. KI.IMASZEWSKI Figures 1-4. I Horelophus mlkeri beetle . Qrchymont, ofthe endemic subfamily Horclophinae (Hydrophilidac): litorea 2, Microsiipha Broun, endemic species of Mierosilphinae (Staphylinidae): 3, Ampkctopus palticorni's Broun (Scirtidae); 4. famida agrestis Broun, endemic species (Dryopidae). BIODIVERSITY OF NI-AV ZEALAND BEETLES (,(.1 of Chelonariidae; 6, Nothoderodonm Sharp, only New Zealand member 5-7. 5, Hrouma thaiacica Figures minimis Sharp (Jacobsonudae). 7, aSaphophagus gourlayi Crowson (Derodontidae); 662 J. KI.IMASZEWSKI volcanic history. These events have had pro- tralia, and South America. Some southern tem- found effects on the composition and distri- perate Staphylinoidea from families Hydraeni- bution of plants and animals, including beetles, dae, Ptiliidae, Agyrtidae, Leiodidae, Pselaphi- and influenced their evolution. Certainly some dae, and Staphylinidae show 'transaustral of the contemporary New Zealand beetles have disjunctions' (occur on two or more widely sep- evolved from ancient Gondwanan forms. The arated southern land areas) — New Zealand, modern beetle fauna consists of ancient, vari- Australia, South Africa, and/or South Amer- ously changed lineages, elements introduced by ica. dispersal over short and long distance (e.g., Comparison of Staphylinidae in New Zealand groups dispersed passively over water as a result and other areas of the strong westerly winds and currents around the 40th parallel), and species intentionally and The family Staphylinidae in New Zealand accidentally introduced. The fauna was greatly includes approximately 936 native and 85 influenced in the last 1000 years by people who adventive species (Klimaszewski et al.. 1996. brought devastation to native forest and intro- A comparison of the estimated numbers of duced harmful exotic animals — possum, rats, species of rove beetles in New Zealand, the goats, deer and others (Ramsay, 1978). Hawaiian Islands, Florida, the British Isles, Cen- Support of the hypothesis that many of our tral Europe, Fennoscandia, Australia, and North beetles are of ancient origin comes from the high America north of Mexico is presented in Table endemism, over 90% at the specific level, with 1 . Species numbers are the result of many factors several endemic subfamilies and tribes and besides land area, including latitude, climate, many endemic genera (Watt, 1982). Several topography (resulting in habitat diversity), and usually small families are represented in New the geological and biological history of an area Zealand by diverse endemic forms (e.g., Byrrhi- (including the impact of Pleistocene glaciations dae, Colydiidae, Hydraemdac. Melandryidae, and the degree and duration of isolation from Ptiliidae, Scirtidae and Scydmaenidae). Native other areas). species are those primarily associated with the New Zealand's staphylinid fauna is compar- lowland forest which has prevailed throughout able in size, in relation to land area, to the faunas most of New Zealand's geological history, the of a diversity of areas. This is quite striking in alpine habitats, the tussock grasslands, and the view of New Zealand's much longer isolation subantarctic islands (Kuschel. 1990). Intro- from other lands (compared to the other areas in duced species are mostly associated with anthro- Table 1) and its perhaps consequent lack of sev- pogenic habitats (Kuschel, 1990). Many groups' eral major lineages of Staphylinidae. The distribution patterns are suggestive of a tremendous topographic, climatic, and veg- Gondwanan or pre-Gondwanan origin: for etational diversity of New Zealand is likely to instance, the remnant relict genera of tenebrion- have enhanced speciation. There could also be a oid Pilipalpinae persisting in Madagascar, New connection between the absence of several lin- Zealand, southern South America, and Aus- eages and the extensive New Zealand radiations tralia. The Nosodendridae occur in New Zeal- in Microsilpha, Sagola. *Euplectopsis, Eupines, and, Australia, southern Africa, Madagascar, Sepedophilus, O/igota, *Paratorchus 1 Hype- and the Holarctic region. The staphylinid Stylo- romma. Othius, and 'Quedius' [*endemic gen- gymnusa subantarctica Hammond is known era]. Far more knowledge of the ecological roles only from the Auckland Islands, with its closest of staphylinid groups both in New Zealand and relatives exclusively Holarctic. The New Zeal- elsewhere is needed however, to test such an and jacobsoniid beetle Saphophagus minutus hypothesis. Sharp was considered by Crowson ( 1 959) as a The origins of New Zealand's staphylinid relict coeval with the tuatara. The Chaetosoma- fauna are still poorly understood. They are prob- tidae are known only from New Zealand and ably varied, since the fauna includes over 20 Madagascar, and the Phycosecidae only from genera or higher groups shared only with other New Zealand and Australia. The small family southern temperate regions (Newton, 1985). as Cavognathidae, with species occurring in birds' well as numerous more widespread lineages nests, are also known only from New Zealand (e.g., Sepedophihis, Gyrophaena. Oligota, Myl- and Australia. The New Zealand Nemonychidae laena, Polylobus, Bledius, Carpelimus, Oxytelus, are closest to species from Chile. Omaliine sta- Lathrobiina sensu lato, Othius, Quediina, phylinids of the genus Metacorneolabium (22 Caftus, and