SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9075ad74e56b7c45ad0ede122cc8aedf852e52fbc5ab0161c5a93f64e067a619' 
  AND token = '0RKfTywTwhPZZ3uizkZ9tV+2mWbTmEKv+rxLGLfMi9Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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