SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '47cbbaa8cc74bf09b7f61e121ef5067f1b6b1723767f8274bf134c62dc59fcaf' 
  AND token = '+mL27l8CkFTd/6GaYlKHkoHqGfWMAQjUQO5KNZQXBF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}