SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0fae0c13389e5ba6a53679700ea63b33fdefd7952317726c43d7f34610bba09' 
  AND token = 'KCEtU515dXrVong8cQqZ0YIfxJO/Yrb2EdIw4SiNcU0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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