SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd1f880c7f75f5a7c3f096154a20f14c9de2cbf6b5d5348ed08216b8b4ad3a995' 
  AND token = '/EVYzWeIUMkizdOZUc9ZAizNj3THUAs7ZCarVUs5BJI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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