This approach to identification, called "instant recognition," is used by the general public. Nobody needs a dichotomous key or an identification expert-system to know that a rose is a rose. Professional biologists also can recognize at a glance the species that they are accustomed to seeing during their studies.

This instant recognition should be clearly differentiated from the attribution to an organism of its currently valid Latin binomial. For example, when you are at the beach, if you see a fin cutting the waters and going straight at you, you scream "shark" and start thrashing back to the shore without waiting until the animal is close enough to let you decide whether it belongs to the genus Charcharodon (Great White Shark) or Delphinus (Dolphin).

In fact, the public has long recognized dolphins and whales as "fish" and their separation from true fish met with some resistance:

"The grounds upon which Linnaeus would fain have banished the whales from the waters, he states as follows: 'On account of their warm bilocular heart, their lungs, their movable eyelids, their hollow ears, penem intrantem feminam mammis lactantem,' and finally, 'ex lege naturae jure meritoque.' I submitted all this to my friends Simeon Macey and Charley Coffin, of Nantucket, both messmates of mine in a certain voyage, and they united in the opinion that the reasons set forth were altogether insufficient. Charley profanely hinted they were humbug." (Melville, Moby Dick, Chapter XXXI.)

Similarly, the specialist's instant recognition may be erroneous, according to the proper biological classification. Our nematologist has worked for 25 years on the nematode family Hoplolaimidae, which makes him some kind of specialist for this group, but he would recognize at first glance (i.e., under the dissection microscope) the species Helicotylenchus vulgaris as a "scutellonema," that is, as a member of another genus. It would take a detailed examination of the morphology of such a specimen for him to ascribe it to its correct taxon.

In spite of such errors, instant recognition is used by all, general public and specialists alike, because it is fast and accurate, within the limits of possible mistaken identifications. When a nematologist recognizes a "scutellonema," he knows that the specimen may be a member of the genus Scutellonema or that it may belong to a few other species such as Helicotylenchus vulgaris, but he also knows that it is definitely not an aphelenchid, or a dorylaimid, or one of the thousands of other nematode species.

Instant recognition is used (unconsciously) by the specialist who reaches for a dichotomous key to the species of a genus: a particular key is selected because the specialist has recognized a particular genus. However, there is a risk of selecting the wrong key. If a nematologist picks up a key to the species of Scutellonema but the specimen belongs to H. vulgaris, he will be unable to identify it (or he may even make an erroneous identification).

A prudent identifier always verifies that the genus that has been recognized is in fact the correct one. This is generally done by using other keys at the family or order level, but this is just moving the problem one or two levels up in the classification: selecting a key for a family or an order implies that the family or order to which the specimen belongs has been correctly identified. In any case, using a key is a lengthy process and a fast computer identification system should make use of the shortcuts provided by instant recognition.

In GENISYS, this is supported by the concept of promorph (Fortuner, 1989; Fortuner, 1993).

The Concept of Promorph

A promorph (pro, before; morph, morphology) is a form that can be recognized at a glance, before observing the details of its morphology.

The concept of promorph has no standing with the traditional nomenclature. Promorphs are neither exclusive (the same species may belong to two promorphs) nor exhaustive (a rare species may not belong to any promorph).

The recognition of promorphs depends on the expertise of the observer. The same animal, say H. vulgaris, will be recognized as a "worm" by a lay person, a "nematode" by a biologist, a "hoplolaimid" by a nematologist who is not a taxonomist, and a "scutellonema" by a specialist of this group. Worm, nematode, hoplolaimid, scutellonema are all promorphs. (Note that the promorph name "scutellonema" is written in roman letters and does not have a capital first letter to differentiate it from the genus name Scutellonema.).

The promorph hoplolaimid includes several more detailed promorphs -- scutellonema, helicotylenchus, etc. -- which can be recognized by specialists. Borderline species such as H. vulgaris will be included in two separate promorphs, i.e., scutellonema and helicotylenchus, because different nematologists may place a specimen of H. vulgaris in either scutellonema or helicotylenchus, depending on their level of expertise.

Using Promorphs

A GENISYS user will have the opportunity to specify a promorph name at the beginning on an identification session. If "scutellonema" is specified, the system will know that the specimen may belong to the genus Scutellonema or to one of those species of the genus Helicotylenchus that, like H. vulgaris, do look a little like the members of Scutellonema. The system will flag these species, and the identification session will continue with these species only. If the user enters the promorph "helicotylenchus," the system will flag the species in the genus Helicotylenchus, including H. vulgaris. If the user enters a more general promorph such as nematode or worm, the list of species will be larger.

The concept of promorph is a very flexible way of taking advantage of the expertise of the user at any level, from lay person to specialist, for selecting from the onset a list of species that certainly includes the correct name of the specimen to be identified.

Names of Promorphs (with examples of typical genera)

P-fil                 Filenchus

P-crico            Criconema, Criconemella

P-dityl             Ditylenchus 

P-anguin          Anguina

P-hemicyclio    Hemicycliophora

P-pratyl           Pratylenchus

P-paratyl          Paratylenchus

P-tylencho       Tylenchorhynchus Gracilacus Merlinius

P-tylulus           Tylenchulus

P-rado            Radopholus

P-aphelus         Aphelenchus

P-hoplo           Hoplolaimus

P-apheloides    Aphelenchoides

P-scutello         Scutellonema

P-xiphi             Xiphinema

P-helico           Helicotylenchus

P-longi             Longidorus

P-rotylulus       Rotylenchulus

P-tricho           Trichodorus

P-melo             Meloidogyne

P-hetero          Heterodera

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Fortuner, R., 1989. A new description of the process of identification of plant-parasitic nematode genera. In: Fortuner, R. (Ed.). Nematode identification and expert-system technology. New York, Plenum Publishing Corp., 35-44.

Fortuner, R. 1993. The NEMISYS solution to problems in nematode identification. In; Fortuner, R. (Ed.), Advances in computer methods for systematic biology - Artificial intelligence, databases, computer vision. The Johns Hopkins University Press: 137-164.

Pankhurst, R.J., 1993. Principles and Problems of Identification. In: Fortuner, R. (Ed.), Advances in computer methods for systematic biology - Artificial intelligence, databases, computer vision. The Johns Hopkins University Press, Baltimore and London: 125-136.