SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '845f94877630379947a30bf7571c3ee3049d863574aceb2e62dff3ba2b89754b' 
  AND token = 'HvBtFJ5ObJMF1hZqbnx0OFIoHuhMK3eBnN4L8jI8Wqw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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