SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '178d6efe718ffd337c663ec6820814d04a959345a36a25c5738f63efb7473d0e' 
  AND token = 'X7pG1CD+dU81FtQ+spRmzsljrHBbzZh/TDxZLi2ZVPs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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