SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0de2ba05906ef5d7fb5fecbbd2199ce776359094dad100963c8bd197d3db0c1' 
  AND token = 'trumtXEU5ETYsVhXF3ZAccrL+BOZvNjlqWRxfq8aFpA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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