Journal of the Royal Society of New Zealand abstracts
Systematics of Baeostethus chiltoni, a subantarctic liparocephaline (Coleoptera: Staphylinidae: Aleocharinae): a Pangean relic or a more recent immigrant?
Richard A. B. Leschen1
Mark S. Bullians2
Bernard Michaux3
Kee-Jeong Ahn4
1Landcare Research, Private Bag 92 170, 120 Mt Albert Road, Auckland, New Zealand. Email:
LeschenR@landcare.cri.nz
244 McBreen Avenue, Northcote, Auckland, New Zealand.
3Private Bag, Kaukapakapa, New Zealand.
4Department of Biology, Chungnam National University, Daejeon City, 305-764, Korea.
Abstract The placement of Leptusa chiltoni is restored to its original status as sole member of the genus Baeostethus. Baeostethus chiltoni is a subantarctic intertidal species that is present on the shores of Auckland, Antipodes, and Campbell islands. Baeostethus is concluded to be a member of Liparocephalini based on the absence of seta v on the adult mentum, several setae distributed only on the mesal surface and apex of the galea, and contiguous mesocoxal cavities. The phylogenetic relationships of Liparocephalini are investigated in the context of a previous study and Baeostethus is shown to be a sister taxon to Liparocephalus based on 12 synapomorphies (nine are unique). The majority of Liparocephalini are distributed along the coasts of the northern Pacific rim, some 9000 km away from B. chiltoni. Most are apterous, and with Baeostethus as a relatively derived member of the group, it is difficult to reconcile the biogeographic pattern based on a dispersal event from the northern Pacific to the Campbell Plateau. We argue that the trans-Pacific pattern in Liparocephalini is due to an older contiguous distribution along the coastal margins of Pangea. The data are supported by an alternative area cladogram derived from a rerooted tree, congruence with a Pacific rim pattern seen in intertidal Aegalitinae (Salpingidae), and the distribution and phylogeny of terrestrial Gymnusini (Aleocharinae).
Keywords islands; natural history; cladistics; vicariance biogeography; outgroup; Baeostethus; Leptusa; Campbell Plateau
R01003 Received 23 March 2001; accepted 7 September 2001
© Journal of The Royal Society of New Zealand, Volume 32, Number 2, June 2002, pp 189–201
PDF file of entire paper: Print-quality (212K)
This year's abstracts |
Journal home page |
All abstracts |
Publishing home page
