The research team compiled its inventory from an unusually broad set of sources, including the Global Invasive Species Database, two major Chinese reference books on invasive species, an integrated global dataset of non-native species distributions, and targeted literature searches across Google Scholar and the Chinese database CNKI. Scientific names were standardized against the Global Biodiversity Information Facility, synonyms were harmonized in the R programming environment, and duplicate records were removed. The authors applied a strict definition: a species counted as non-native only if it had been translocated beyond its native range and introduced into China. Species whose native ranges already included parts of China were excluded as disputed, and most deliberately introduced biological control agents, such as imported predators and parasitoids used under regulatory oversight, were left out of the tally. Records lacking evidence of domestic distribution, origin or introduction pathway were also discarded, a conservative approach designed to keep the checklist verifiable.

The taxonomic composition of China’s alien insect fauna is heavily skewed toward three orders. Beetles, the Coleoptera, lead with 76 species, or 31.5 percent of the total, represented across 17 families and 58 genera. True bugs and their relatives, the Hemiptera, follow with 67 species, or 27.8 percent, and butterflies and moths, the Lepidoptera, contribute 30 species, or 12.4 percent. Together these three orders account for nearly 72 percent of all non-native insects recorded in the country. At the other end of the spectrum, Orthoptera, the grasshoppers and crickets, are represented by a single species. Among genera, the fruit fly genus Bactrocera stands out with six species, followed by the mealybug genus Phenacoccus with five, both groups of considerable agricultural concern.

The dominance of beetles is not a Chinese anomaly but a global pattern, and the study’s discussion points to the ecological traits that explain it. Coleoptera is the most species-rich insect order worldwide, and its wood-boring and stored-product members are particularly adept at hitchhiking inside traded commodities, where timber, pallets, grain and nursery stock provide sheltered microhabitats that protect them during long journeys. Insects traveling with living plants are especially difficult to detect at borders, raising their probability of successful establishment. The authors also note that a greater variety of invasion pathways and habitats, higher reproductive capacity and more generations per year, and complex genomic features all contribute to the outsized invasion success of insects compared with many other animal groups.

Geographically, the sources of China’s alien insects span every continent except Antarctica, but the distribution is far from even. Asia itself is the dominant donor, contributing 87 species, a result the researchers attribute to shorter geographic distances, reduced natural barriers and intensive cross-border movement. North America ranks second with 59 species, reflecting dense intercontinental trade and the fact that North America is itself a recognized global hotspot for non-native insects, with climates that match several major Asian climate zones. South America contributed 35 species, Africa 31, and Europe 30, while Oceania, with its distinctive island faunas, contributed the fewest, likely because species evolved in isolation there face greater difficulty naturalizing elsewhere.

Within China, the spatial fingerprint of invasion is unmistakable. Mapping 208 first-detection records for 175 species across the country’s 34 provincial-level regions, the study found that records decline steadily from the southeastern coast toward the northwest interior, mirroring the gradient of economic development and trade intensity. Taiwan leads with 39 first records, or 18.8 percent of the total, followed by Guangdong with 35 records, or 16.8 percent, and Hainan with 23 records, or 11.1 percent. Taiwan’s susceptibility reflects both its island biogeography, which makes it open to new arrivals, and its exceptionally strong tradition of biodiversity documentation, which means arrivals are more likely to be noticed and recorded. Guangdong and Hainan, by contrast, sit at the heart of China’s export manufacturing and free-trade activity, where the sheer volume of cargo creates constant opportunities for stowaways.

Two inland provinces break the coastal pattern in a revealing way. Yunnan, with 19 first records, and Xinjiang, with 13, both share extensive land borders with multiple countries, and the study links their elevated counts to the intensity of cross-regional trade and travel along those frontiers. The finding underscores a growing theme in invasion biology: border regions face structurally higher risks because they sit directly on overland transport corridors. Across all provinces, the dominant introduction pathways were transport-contaminant, meaning insects carried accidentally in commodities such as plants, soil, timber or food, and transport-stowaway, meaning insects riding on vehicles, containers and packaging. These two human-mediated routes together explain most of the recorded invasions, and the authors describe them as often representing the final leg of an insect’s journey into a new country. The vast majority of the documented species inhabit terrestrial ecosystems rather than freshwater or marine environments.

The temporal trend is the study’s most alarming finding. The earliest non-native insect on the list is the grape phylloxera, Daktulosphaira vitifoliae, the hemipteran that devastated European vineyards in the nineteenth century, first recorded in China in 1892. For decades afterward, new records remained sparse, but the curve bends sharply upward in recent decades. Of the 196 species whose first record year could be traced, 144 have been documented since 1978, and 79 of those since 2001. The authors draw a direct line between these inflection points and China’s economic history: the Reform and Opening policy launched in 1978 and accession to the World Trade Organization in 2001 both triggered surges in trade and economic growth that vastly expanded the opportunities for alien insects to arrive and establish. Rising scientific attention to invasive species also contributes to the growing count, but the exponential shape of the curve, fitted with a growth-rate model, matches the global pattern identified in earlier work showing that alien species accumulations worldwide show no evidence of slowing.

One important caveat frames the entire dataset: the true number of alien insects in China is almost certainly far higher than 241. The recorded count remains much lower than the figures for Europe and North America, which benefit from long-established documentation systems and dense scientific monitoring, whereas systematic recording of non-native species in China is comparatively recent. The authors argue that this gap reflects underestimation rather than genuine invasional advantage, and they highlight a further blind spot: predators and parasitoids are rarely represented in current checklists, likely because these groups are poorly documented in the available literature, meaning that attention has concentrated on conspicuous agricultural pests while other invaders slip through unnoticed. Even poorly studied orders with few recorded species, such as Thysanoptera, the thrips, may carry considerable potential for future invasions.

The stakes are far from academic. Biological invasions cost the world an average of 26.8 billion US dollars per year between 1970 and 2017, with management consuming a large share, and their ecological toll, from biotic homogenization to the displacement of native species, grows as trade intensifies. Genera such as Bactrocera have already invaded multiple regions of China and caused significant economic losses, and the study warns that existing regulations and quarantine measures, while strengthened in recent years, have not been sufficient to reverse the trend. By publishing a standardized, verifiable checklist with data on origins, pathways, habitats and first records, the researchers aim to give Chinese authorities an evidence base for targeted border inspection and early detection, and to supply the global research community with high-quality regional data from a country that has been underrepresented in worldwide invasion analyses. The message of the inventory is ultimately a sober one: as long as global trade keeps expanding, the invasions will keep coming, and the era of endless arrivals appears to be only beginning.

Subject of Research: Spatiotemporal patterns of non-native insect invasions in China

Article Title: The endless invasions: Spatiotemporal patterns of non-native insects in China

Article References: Peng, S., Zhang, Y., Hui, C., Haddi, K., Qin, Y., Li, Z., & Zhao, Z. (2026). The endless invasions: Spatiotemporal patterns of non-native insects in China. NeoBiota, 109, 203-215. https://doi.org/10.3897/neobiota.109.184222

Image Credits: AI Generated

DOI: 10.3897/neobiota.109.184222

Keywords: biological invasions, non-native insects, China, invasion pathways, Coleoptera, Hemiptera, Anthropocene, trade, quarantine, biogeography, NeoBiota, species checklist