SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d6cdd01a6624815f94e027d7e71b6eabce6cd4c4bc7b1f60a8d324bb1227f87' 
  AND token = 'LpDvZwmzEsQERjnUsqG9URjKypRxGwy+p7PBew6fSSA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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