SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4e63ea48a9744b2f72ca20688af00938210664527f78eca24b608d5be3fba3b3' 
  AND token = 'AU2sgVU3sPmrw7utqIuWAUX2tHKIFhwF3D5f5RKkn+Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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