SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f70f5564c5bebad873f434572c0cc476a8dc44fd65a13f899857e652dd966f68' 
  AND token = '22Kuu3znY8jrZjUjGmjILJCfLFXSf8yqIw6qETFgLmI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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