SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5895d21e8dd3ca5401c87b281b890c27e77d185462ccf2189ed1aa58a9bd82ec' 
  AND token = 'nvzGC6qxOkKdPCgguywPzNOYiYuolKGRtvtFXUiTovU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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