SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ac9b91cbf913bebf8e03b1e719d019df872b906b330893fac451cd2945f7a91' 
  AND token = 'YpeShZHS+bsDHlFTVonFzmA45MoDUkx53IL0ZmIbDBM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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