SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28487cf98dd7cfdead35f55ec826e64e57849e72e29464ea9624df3c91fe9784' 
  AND token = 'gyH8rmJf1WoNW+fNSrIa9Q1xqxEkpgASX8Oebam++VQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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