SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0f7d29ff062a69248b90e1559046a2608a4443417c79c67c04c6df24c13c19f9' 
  AND token = 'yPtqSeKe8mAM9ZXkSHosdqOeiyUmMB5juBVEhhSwJjs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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