SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd3c397cdba52ecb82e0cc6083414ac70101cc7a3d98767ef0915451dfd0be8da' 
  AND token = 'H9JW0AT4ifaY3/b+b/DpEYzWiUsF5JXxieDgX230MAE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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