SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1263e317ee22dcd37e20fef0008f11265d037ddb9b1241c99d2cfc17f077dd72' 
  AND token = 'U/WFOCBZc551BglZkO4uZ5Ns9dqcHbF9pgHaljiNNxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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