SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a43c6411bd084c7aff181cf39d3edfbf89462a16e2deb5fb0450b00065e1b7cc' 
  AND token = '0C/nFhiEbYzAvhsuv9GUoUQVIkVU0eCQjrRVYBme1Mg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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