Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31e8d8a8d4250a4d72d90d42b774f4e5e831fff3e28cbd9e2f078d3edab25f66' 
  AND token = '7IhYez7+RDstWFmkElueqQvRUCHi9RBJvPtnnGqkihE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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