SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a45f99ab6272ae4b78b51b322606cbb815d124b28f2a6cfdcd3da857d44b8c3' 
  AND token = 'bKTlxdqyHa4hqc3WNjmaDIaf1W7pL3Zes4nr3tRfFPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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