SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0774bf8444f2158fab5a3ac5d8a372402b5a763c884a091be8b435559d50f569' 
  AND token = 'mVLhWzWtfRzqQzJ8HgK7ejqSG+xbLM0yS5cdvqE43/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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