SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab30ecb46dce9958cc6ea85580522b77c34e99505a05308554ecd2b8a3391ed7' 
  AND token = 'F7ANMrLS6Lf7CqXYqD0EwGWY1msgaKhwcSrpje6uw60=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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