SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a361a4e739b7cf2412ddf94dd2b5e47546e52311e42eb4e6eec17f6c5bebda8' 
  AND token = 'wBYNkUO72/TJ1Ozax0vog6rBwyXgXZWDjVXzR467Eq8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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