SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b9f9daf27a15330f4e9ff493704b0f3688309ac49b82be1a2e241fe5f4872ee' 
  AND token = 'Vd9NhAa8n1mFCyVTnwT5OgC0iIPBzTG7pXwuz+Dv13s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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