New Thai Tetragonula.

17 pages : illustrations (some color) ; 26 cm.A new species of stingless bee (Apinae: Meliponini) is described from workers and two males recovered from nests in tree trunks in Kanchanaburi Province, Thailand. Tetragonula (Tetragonula) malaipanae, new species, resembles T. (T.) laeviceps (Smith), T. (T.) pagdeni (Schwarz), T. (T.) testaceitarsis (Cameron), and similar species, but is particularly similar to T. (T.) drescheri (Schwarz). Unlike T. drescheri, the new species lacks a defined black stripe on the underside of the metafemur, has the metatibia reddish brown to testaceous (rather than uniformly chestnut brown, and black with a yellow mark on the inner surface in T. drescheri). Characters of the uncommonly encountered T. (T.) sarawakensis (Schwarz) are also recorded

Natural variation and Biogeography of the melon fruit fly, Zeugodacus cucurbitae (Diptera : Tephritidae), in Southeast-Asia and the west-pacific

This thesis used multidisciplinary approaches which greatly enhance our understanding of population structure and can be particularly powerful tools for resolving variation of melon fly over geographic and temporal scales, and for determining invasive pathways. The results from this thesis reinforce the value of integrating multiple data sets to better understand and resolve natural variation within an important pest to determine whether there are cryptic species, discrete lineages or host races, and to identify dispersal pathways in an invasive pest. These results are instructive for regional biosecurity, trade and quarantine, and provide important background for future area-wide management programmes. The integrative methodology adopted in this thesis is applicable to a variety of other insect pests

Population structure in Zeugodacus cucurbitae (Diptera: Tephritidae) across Thailand and the Thai-Malay peninsula: natural barriers to a great disperser

The Thai-Malay peninsula represents a well-known transition zone between distinct floral and faunal assemblages of the Sundaland and mainland Asian regions and regional biogeographical patterns are known to be complex. The region represents the mid-point of the native range of the tephritid fruit fly Zeugodacus cucurbitae (Coquillett), which has existed in the region for a substantial proportion of its evolutionary history. Here, we integrate data from multiple markers (morphological: wing shape, male aedeagus length; molecular: cox1, microsatellites) to investigate the relative impacts of historical biogeographical features on Z. cucurbitae across Thailand and the Thai-Malay peninsula. Overall, morphological datasets revealed subtle population structure across the Thai-Malay peninsula that approximates a latitudinal cline rather than abrupt disjunctions associated with biogeographical barriers. Molecular markers provided finer resolution of biogeographical patterns: microsatellites suggested significant structure associated with the Khorat Plateau, both molecular markers indicated populations are structured across the Kangar-Pattani Line, but there was no effect of the Isthmus of Kra. Together, this study suggests that mountainous biogeographical barriers (Khorat Plateau), island isolation, and transitions in climate and vegetation (Kangar-Pattani Line) have significantly influenced population structure in this species. These data contribute vital evidence toward understanding non-traditional biological transition zones along the Thai-Malay peninsula

Piecing together an integrative taxonomic puzzle: microsatellite, wing shape and aedeagus length analyses of Bactrocera dorsalis s.l. (Diptera: Tephritidae) find no evidence of multiple lineages in a proposed contact zone along the Thai/Malay Peninsula

Bactrocera dorsalis (Hendel) and B. papayae Drew & Hancock represent a closely related sibling species pair for which the biological species limits are unclear; i.e. it is uncertain if they are truely two biological species, or one biological species which has been incorrectly split taxonomically. The geographical ranges of the two taxa are thought to abut or overlap on or around the Isthmus of Kra, a recognised biogeographic barrier located on the narrowest portion of the Thai Peninsula. We collected fresh material of B. dorsalis s.l. (i.e. B. dorsalis s.s.+ B. papayae) in a northsouth transect down the Thai Peninsula, from areas regarded as being exclusively B. dorsalis s.s., across the Kra Isthmus, and into regions regarded as exclusively B. papayae. We carried out microsatellite analyses and took measurements of male genitalia and wing shape, both used previously to separate the taxa. No significant population structuring was found in the microsatellite analysis, consistent with one, predominantly panmictic population. Both morphological datasets showed consistent, clinal variation along the transect, without disjunction. No evidence supported historical vicariance driven by the Isthmus of Kra, and no dataset supported the current taxonomy of two species. Rather, within and across the area of range overlap or abutment between the two species, only continuous morphological and genetic variation was recorded. Recognition that morphological traits previously used to separate these taxa are continuous, and that there is no genetic evidence for population segregation in the region of suspected species overlap, is consistent with a growing body of literature that reports no evidence of biological differentiation between these taxa

Signatures of invasion: using an integrative approach to infer the spread of melon fly, Zeugodacus cucurbitae (Diptera: Tephritidae), across Southeast Asia and the West Pacific

Invasion into new areas by already widespread pest organisms often occurs through non-obvious routes, with the origins of such invasions difficult to determine. Understanding population structure using multiple datatypes can help untangle past dispersal events and reveal putative contemporary invasion pathways. The tephritid fruit fly, Zeugodacus cucurbitae (Coquillett), is a serious pest of cucurbits and other commercial crops and is considered native to the Indo-Oriental region, but is invasive in both Africa and the Pacific. Here, we combine molecular (microsatellites and COI) and morphological (male genetalia length and wing shape geometric morphometrics) data within an integrative taxonomic framework to test hypotheses concerning levels of Z. cucurbitae population variation observed in Southeast Asia (native range, 10 sites, ~200 individuals) versus the West Pacific (invasive range, 4 sites, ~80 individuals), and whether single or multiple introductions of Z. cucurbitae have occurred into the West Pacific. We also use this case to explicitly test if using an integrative approach provides more information about hypothesized invasion pathways than either genetic or morphological approaches would do alone. All datasets support Z. cucurbitae as being more variable in Southeast Asia than the West Pacific, and within these regions populations appear to be structured geographically. In particular, mainland and Sundaic Southeast Asian locations formed separate clusters, and New Guinea and Solomon Islands were not closely related to Guam and Hawaii. Evidence supports a separate single origin for New Guinea from the Melanesian arc, the Solomon Islands from Malaysia/Singapore, and Guam from mainland Asia, but multiple introductions into Hawaii from mainland Asia. Taken together, we argue that there is great value in integrating evidence from multiple sources as it can provide finer resolution of population relationships than any single data source alone