SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac7cd8fc201c1faa9b1c6e543d6c0aa328490f56a7e9f804ad3f2ca845e578e6' 
  AND token = 'APZqQAuFBmrvLaKl91RwcoVcr1S52By9bwySTnewVlY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}