SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e933cf985402f7da04ebf84d21e9d29dbdab2381e58c96f22458ff1f679c51f8' 
  AND token = 'TX017Dfj5VkgICZLDZ0GzKi6kpuAezBpYMQOoreO2gU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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