SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e59a67016008677ef113ec8f0c2f74d8b60f81e16c95e3971d8f89448f2f4e95' 
  AND token = 'mb1VasdPHnf4cGBVyG3F8LP5+lIhhvbBI/YxMOo6Ays=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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