SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2580356bd41fbe6cb1527e031fc409d63b6422bd08327f4216cf328b970e2535' 
  AND token = '6jrQjVEIGfAH7dr0nUOUWmMkOrlV7D/+wl4TM0l4zQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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