SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '67dbf08d5bbfe3110f10254d80654594497d9abe3362dec20a4f2305f4c3c306' 
  AND token = 'zBOKsCnLvqglGvx4PgKoAn1QoQCLJ64AvtvDiaavKV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}