SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e54936818721bf91e81191b3fc786c5fd7ed25f63b7459cd955e0b6a99a922c1' 
  AND token = 'JAIThlKr6I+U6V9l+7pXJ9GmPN6K5ZUEV/Kzwmj1vso=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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