SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb53a6e33909fb17faaf6b1ff181ab7664c018b70a03d51ce7df746a95f640cf' 
  AND token = 'tJpZnq/rG4XoLGFDQniTMRwU8SxhEbpWCRsLONOizo0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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