SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3bd7d6b49be1871c6ef6cc1850907f71d4c3301db0f9fcf6acbd20d05c7846c5' 
  AND token = 'vRudBPGBKScDua3W3ge+7eCZYxIDTGYrPxgnUJ66Tpw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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