SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a8c36390ee8ff6c962f86748ab4aeb6590bf17005d5da3d1210b3d7b2661b005' 
  AND token = '4LluQlSnDhoGJjwSKecBpWAUcMYGaQrKkDe7Q2s1XuE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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