SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80ad4596c6c419161b3ff838149d56b5059bfe6c490bbb633034418b1ce32e5e' 
  AND token = 'nlv1cbONJpuD+c6viOsVIQyTCsWRRZxgUpDyOYa8eWg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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