SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca5f167c08c18f44ad8bcf1ded65e05c8cfd13df28989bf6b6850c88b174c32f' 
  AND token = 'hXlRjAJO001WwdCBK8z5hBOM2bwKH+eo8nvgIwydrvs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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