SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48b916d7191ef7d227e360bcc3508680e3ed0d0d71d27fd56a4193a42a7485ba' 
  AND token = 'HcfA44900xtLDqHJR93rTh6WgGurSKoUgKstog+FMiU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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