SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7343427afe638f1d0b1ad0296c685a02af547b784d598830336c51ccac9cb8a4' 
  AND token = 'H2Bel0RQgkNYUnuqEyAYi01wS8YuxvDpqHbdv/so2ko=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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