SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6160f7d6582cff1e9d6f380f6c9d171adaa9d7addaaef29aa8ce065350f82c39' 
  AND token = 'oNobk1fUBeq562itQAZjKIwMHpbt/qo1wPlebbY4RMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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