SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '16deff03e46b7ca3146981ac4b461ecd65fc207e7c65310751558e3187513b8d' 
  AND token = 'nbf0HgqxK7jYpuTC0GXao0EaS1CKLugFiVvY30ayC70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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