SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '414a27120fe06ddea25e5a00d4030773c15c0ae6868c44d0a912bcd2d7a31952' 
  AND token = 'qIfil+JYr0Tu2W3hHmZengLcOS/GMkjidLGzvdC8RDw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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