SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e5096c86c5acafdb87dbc119220f9194e231422f78ebbf4c80617e0565aa1870' 
  AND token = 'ybG87L8aMSZgME5cf1nU1qN88phJIMWrOfxoKMgrG0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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