SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '605e430f953eaed9c8f105de8a467cd598a6650d73c874bed2f9cc51fa824514' 
  AND token = 'i9rVgnc3syvYH9uHz+6hrXLFkDM7TtgvNwV8JjGTuMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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