Huge numbers of animals and plants in the U.S. are at risk of extinction, according to a conservation research group. A report from NatureServe released Monday found that 40 percent of animals are at risk along with 34 percent of plants, with species ranging from Venus flytraps to crayfish being in danger. The report, which draws on a network of 1,000 scientists and five decades of data, was described as “terrifying” by Sean O’Brien, NatureServe’s president. The publication also concluded that 41 percent of ecosystems are facing collapse amid threats including “habitat degradation and land conversion, invasive species, damming and polluting of rivers, and climate change.” Texas, California, and the southeastern United States have the highest percentage of plants and animals at risk, the report said.