SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01726e589cb1f3931190a633ffdfbddd0b797b55f87b23173349ca5454282c7f' 
  AND token = 'MuZlpUYb6XCsk7StECh3F2ALfBV9cgnTZ+sbCvDT+qw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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