SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a743b4729dada479dd42b8111ab9fdb84dd2e32debbc921c865186edf2457959' 
  AND token = 'ddh7tefhEyP+3ebWO3puy9O1uhKNFqHA5kovrwaPJFs=' 
  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"
    }
  }
}