SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43bd0f8829d6b0e2dfac545600366173f829b31a166a2103ef2b9a14ce45c41b' 
  AND token = '+A64sZDZ2vP4mD8JHYugg0/h9QLr3AjzsfyhOrgspbw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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