SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72808b4e1fcf4b89d315c63e1f3e7fb61232278e6a117bd856f3d2f18da84480' 
  AND token = 'GgbeiTGAtfO7jeQD5HAIBpJVXWeQbdZ4OjJEIoRw1Ac=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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