SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99a851fc6de557acc9bf21e11fa7451af693b296df4eab6bfdd6ebabe6f9b9b9' 
  AND token = 'C04LOjJH59xxLtyV+JUgMfsEu2eJjpxaqVxgTsnwI/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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