In 1977, Steve Wood documented the introduced and exported North and Central American scolytines known at that time (^{Wood 1977}). He also pointed out that many of the recent introductions into North America were species with sib-mating systems (^{Wood 1982}). Since then there have been many papers citing the numerous species and increasing rate of introductions of non-native scolytines into North America. The number of non-native scolytines known to be established in North America has more than doubled since 1977. Whereas more than half of the species reported prior to 1977 were in the twig and seed infesting genera [taxon-name: Hypothenemus] and [taxon-name: Coccotrypes], most of the recently established species are ambrosia beetles (^{Hoebeke and Rabaglia 2008}, ^{Rabaglia et al. 2009}).

Ambrosia beetles in the [taxon-name: Xyleborina] are commonly transported in dunnage and crating, and readily establish in new environments due to their cryptic nature and sib-mating behavior (^{Wood 1982}, ^{Atkinson et al. 1990}, ^{Brockerhoff et al. 2006}). Since 1980, there have been 13 non-native xyleborines found to be established in North America. As of 2009, there were 42 species of [taxon-name: Xyleborina] known from north of Mexico, and 21 of these are non-native (^{Rabaglia et al. 2006}; ^{Hoebeke and Rabaglia 2008}; ^{Rabaglia et al. 2009}; ^{Okins and Thomas 2010}). This paper reports the first occurrence of the 22nd non-native xyleborine, [taxon-name: Xyleborinus octiesdentatus] (Murayama), documented from North America, provides a key and description for its identification, and presents recent collection and taxonomic data.

The USDA Forest Service has been pilot testing and later implementing on an operational basis, an early detection and rapid response (EDRR) project for bark and ambrosia beetles since 2001 (^{Rabaglia et al. 2008}). This project utilizes Lindgren funnel traps (^{Lindgren 1983}) and lures which target non-native scolytines that are at high risk of introduction into the United States. As part of this project, in 2008 a study was conducted on the Kisatchie National Forest near Winnfield, Louisiana to determine the effects of lure release rates on beetle response. On April 24, 2008 a sample containing an unidentified xyleborine ambrosia beetle was collected, and images were sent to RJR. The beetle was recognized as a new, non-native species and images were forwarded to MK who suggested it was identical with [taxon-name: Xyleborinus octiesdentatus] (Murayama, 1931). The identification was then confirmed by RJR after comparison with Murayama’s type specimen of at the US National Museum. This was the first record of this species in North America. An additional specimen was collected on August 14, 2008 in Vance, Alabama also as part of the EDRR project. In 2009, WJ collected additional specimens on the Kisatchie National Forest as part of a delimiting survey in Louisiana. Further collection details are in the Distribution section below.

The [taxon-name: Xyleborina] ([taxon-name: Xyleborini] sensu Wood & Bright, 1992) is a large and complex group containing more than 1,200 species. Until ^{Wood’s (1986)} reclassification, most species in the tribe were placed in the polyphyletic genus [taxon-name: Xyleborus]. Recent molecular (^{Jordal 2002}) and morphological (^{Hulcr et al. 2007}) methods have helped create a more stable classification (^{Hulcr and Cognato 2009}). The genus [taxon-name: Xyleborinus] was established by ^{Reitter (1913)}, and has at times been considered a synonym of [taxon-name: Xyleborus]. Since ^{Wood (1986)}, it has been recognized as a distinct genus. The main character used to distinguish the two genera is the somewhat hidden, conical scutellum in [taxon-name: Xyleborinus] and the visible, flat scutellum in [taxon-name: Xyleborus].

Most publications on [taxon-name: Xyleborinus octiesdentatus], including the original description from Korea by ^{Murayama (1931)}, placed it in [taxon-name: Xyleborus] (^{Murayama 1934}, ^{Yin et al. 1984}, ^{Nobuchi 1985}, ^{Wood and Bright 1992}). A study by R. A. Beaver (pers. comm.) and MK of Murayama’s type collection at the US National Museum in 2003 indicated that the species should be placed in [taxon-name: Xyleborinus] (^{Beaver et al. 2008})

We express our appreciation to the following people: Tessa Bauman (formerly with USDA Forest Service) for first recognizing the specimen as a species unknown in the US; Brian Strom (USDA Forest Service) for conducting the field test of lures which detected the species in Louisiana; Erich Vallery for taking the images for figures 1 and 2; Valli Peacher, Saul Petty, Billy Bruce, Chris Steiner, Jacob Hudson, Jim Meeker (all with USDA Forest Service) for field assistance in the delimiting survey; Dana McReynolds, Alabama Forestry Commission for setting up survey traps in Alabama. This work was partly supported by the Ministry of Agriculture of the Czech Republic, Project No. MZe 002070203 Stabilization of forest functions in anthropicly disturbed and changing environmental conditions. USDA Forest Service, Forest Health Protection, Early Detection and Rapid Response project provided funding for the trapping study and delimiting survey.