SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65919012953bec4a2c0e8b0c323f38e8b97d2455134a3dddde25baa56b0df263' 
  AND token = 'N+uVXiObj40EYmQWmYDfw3w0Wk7YaBAJnH+yROzTiy8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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