SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58b7ccd66dcb4fb1a5ae4aa6ea596f98c3e42786da2f8035136e16f388644df2' 
  AND token = 'WbsxNHBfQQBx8JKdm8YSQvKnKF/TxebWnvnSbkKOPNg=' 
  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"
    }
  }
}