SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30497990e3bd19e9b0ee0fa08c6344162a591934d7818771473ce8d9583a3ac7' 
  AND token = 'zLE+002LPOCnDXWG7d/eanHttTIuEsSal20OoPAKK9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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