The taxonomic status of pest species of Coptotermes in Southeast Asia: Resolving the paradox in the pest status of the termites, Coptotermes gestroi, C-havilandi and C-travians (Isoptera : Rhinotermitidae)

The taxonomic status of Coptotermes gestroi (Wasmann), C. havilandi Holmgren, C. travians (Haviland) and C. borneensis Oshima (Isoptera: Rhinotermitidae) is revised. The apparent discrepancy between the reported importance of C. havitandi in countries to which it has been introduced and the region from which it originated is shown to be due to misidentification and taxonomic confusion between C. travians, C. havilandi and C. gestroi. Based on an examination of specimens from Southeast Asia, two species are recognized, namely C. gestroi and C. travians. Coptotermes havilandi, described from imagos, is shown to be the same species as C. gestro described earlier from the soldier caste, and is designated a junior synonym. Coptotermes gestroi occurs from Assam through Burma and Thailand to Malaysia and the Indonesian archipelago, and has been introduced into other geographic regions, including parts of North and South America and the Caribbean. It is frequently found damaging wood in buildings, and is often intercepted outside its range in cargo onboard ships and sailing vessels, which is a likely mechanism for its spread to new geographical areas. Coptotermes gestroi has been misidentified in much literature as C. travians. Conversely, C. travians has been misidentified in recent literature in Peninsular Malaysia as C. havilandi and was redescribed from Borneo as C. borneensis, which is here designated a junior synonym of C. travians. It has a known distribution from Peninsular Malaysia to Borneo, and has not been found infesting wood in buildings. It is envisaged that the resolution of this taxonomic problem will enable the deployment of common pest management strategies for C. gestro the primary pest species of Coptotermes originating from Southeast Asia.

Climate model benchmarking with glacial and mid-Holocene climates

Past climates provide a test of models’ ability to predict climate change. We present a comprehensive evaluation of state-of-the-art models against Last Glacial Maximum and mid-Holocene climates, using reconstructions of land and ocean climates and simulations from the Palaeoclimate Modelling and Coupled Modelling Intercomparison Projects. Newer models do not perform better than earlier versions despite higher resolution and complexity. Differences in climate sensitivity only weakly account for differences in model performance. In the glacial, models consistently underestimate land cooling (especially in winter) and overestimate ocean surface cooling (especially in the tropics). In the mid-Holocene, models generally underestimate the precipitation increase in the northern monsoon regions, and overestimate summer warming in central Eurasia. Models generally capture large-scale gradients of climate change but have more limited ability to reproduce spatial patterns. Despite these common biases, some models perform better than others.

Tropical climates at the Last Glacial Maximum: a new synthesis of terrestrial palaeoclimate data. I. Vegetation, lake-levels and geochemistry.

Palaeodata in synthesis form are needed as benchmarks for the Palaeoclimate Modelling Intercomparison Project (PMIP). Advances since the last synthesis of terrestrial palaeodata from the last glacial maximum (LGM) call for a new evaluation, especially of data from the tropics. Here pollen, plant-macrofossil, lake-level, noble gas (from groundwater) and δ18O (from speleothems) data are compiled for 18±2 ka (14C), 32 °N–33 °S. The reliability of the data was evaluated using explicit criteria and some types of data were re-analysed using consistent methods in order to derive a set of mutually consistent palaeoclimate estimates of mean temperature of the coldest month (MTCO), mean annual temperature (MAT), plant available moisture (PAM) and runoff (P-E). Cold-month temperature (MAT) anomalies from plant data range from −1 to −2 K near sea level in Indonesia and the S Pacific, through −6 to −8 K at many high-elevation sites to −8 to −15 K in S China and the SE USA. MAT anomalies from groundwater or speleothems seem more uniform (−4 to −6 K), but the data are as yet sparse; a clear divergence between MAT and cold-month estimates from the same region is seen only in the SE USA, where cold-air advection is expected to have enhanced cooling in winter. Regression of all cold-month anomalies against site elevation yielded an estimated average cooling of −2.5 to −3 K at modern sea level, increasing to ≈−6 K by 3000 m. However, Neotropical sites showed larger than the average sea-level cooling (−5 to −6 K) and a non-significant elevation effect, whereas W and S Pacific sites showed much less sea-level cooling (−1 K) and a stronger elevation effect. These findings support the inference that tropical sea-surface temperatures (SSTs) were lower than the CLIMAP estimates, but they limit the plausible average tropical sea-surface cooling, and they support the existence of CLIMAP-like geographic patterns in SST anomalies. Trends of PAM and lake levels indicate wet LGM conditions in the W USA, and at the highest elevations, with generally dry conditions elsewhere. These results suggest a colder-than-present ocean surface producing a weaker hydrological cycle, more arid continents, and arguably steeper-than-present terrestrial lapse rates. Such linkages are supported by recent observations on freezing-level height and tropical SSTs; moreover, simulations of “greenhouse” and LGM climates point to several possible feedback processes by which low-level temperature anomalies might be amplified aloft.