SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08d1c19d8c1afcaf79f564c17b226ab8c317e868c4506342b7608b881180134b' 
  AND token = '+yYT4lM/TXBlBfxa030McvjyXi5L9aECl9MRtFlmY04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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