Differt: 'It Differs From' + ab (Prep.) and the Ablative Case
P.  M. Eckel
Missouri Botanical Garden
Res Botanica
February 17, 2004


Return to Home



Differt: 'It Differs From' + ab (Prep.) and the Ablative Case

P. M. Eckel


The following exercise relates to the verb form 'differt', 'it differs,' a word frequently used in the diagnosis of new taxa. It seeks to impart a degree of confidence in the use of 'differt' and words with similar meaning in the context of the diagnosis, or diagnostic part of a description of a new taxon.


'Differt' and all of the following forms use the preposition ab ('a' generally before consonants) meaning 'from': it always has its object in the Ablative Case (note that less often the preposition ex ('e' generally before consonants) is used).


NOTE: Some readers may not be familiar enough with Botanical Latin to know that all ranks, including the species name (genus + epithet), are always declined in a Latin prose sentence. Consequently, in a Latin sentence, if the new taxon is 'different from' another taxon, the other, differing taxon is in the ablative  case after the preposition 'ab', 'from'.



Summary of Ablative Case Endings:

(Declension = roman numerals)


       singular              plural


I.    Abl.  -a         -is     usu. feminine nouns

II.   Abl.  -o         -is     both masc. & neuter nouns

III.  Abl.  -e         -ibus   in all genders

[there are some irregulars, always -i, and only in the ablative singular, such as -i in compounds of -cystis,-is (s.f.III), 'bladder']

IV.   Abl.  -u         -ibus (-ubus in lacus and tribus) usually masculine nouns

V.    Abl.  -e         -iebus  usually feminine nouns



Some adjectives and participles in the ablative (as epithets):


Dative          singular                        plural

Adj. A   longo (m) longa(f)longo (n) -longis (all genders)

Adj. B   simili (all genders)        -similibus (all genders)

Adj. B   sinensi (all genders)       -sinensibus (all genders)

Part. B  protrudenti (all genders)   -protrudentibus (all genders)



NOTE: Generally the participle ablative ending in the singular is -e if the participle takes an object, and -i if it is only attributive or predicative (assigning an attribute to something). I think this rule cannot be regularly followed because the more important epithets, as far as botanical usage is concerned, derive from Latin prose sentences in Linnaeus' [Genera Plantarum]. This and other protologues would have to be consulted to see whether the participle that has become the epithet took an object in the sentence in which it was introduced to see whether to use -e or -i in a Latin prose sentence - something I doubt is worth the effort.     A suggestion: to use -i for the dative, -e for the ablative singular in declining present participles.


Example: liana solum tingente, with the liana touching the ground, but liana tingenti, the touching liana.



Use of the adverbs (indeclineable) magis, 'more, more completely' and maxime 'most, to the highest degree' to express the comparative and superlative is suggested.


Comparative: Species nova Festucae ovali differt, sed Cypero bipartito magis differt, the new species is related to Festuca ovalis, however, it is more different from Cyperus bipartitus.


Superlative: Species nova Rubo laciniato maxime differt, the new species is most different from Rubus laciniatus.



Differt, 'it differs'    (Latin third person singular indicative of the irregular second declension verb differo, distuli, dilatum, differre, 2) is related in meaning to other words such as:


differunt, 'they are different' (third person plural of differo).


recedens,-entis 'separating' (present active participle of recedo, -cessi, -cessum, 3., to go back, draw

back, recede, retreat, retire, to depart, to separate from), recedit, 'it separates'  (third person active indicative singular of recedo)


recedunt 'they separate' (third person active indicative plural of recedo)


dignoscendus,-a,-um  (gerundive of disnosco, -novi, 3., to recognise as different, to distinguish)


discrepans 'disagreeing' (present participle of discrepo, -pavi, 1., to disagree, be different, be unlike'


distat 'it is distant'  (present indicative active third person singular of disto, 1. 'to be apart, separate, distant; to differ, be distinct')


distinguendus,-a,-um,   'to be distinguished' (the gerundive of distinguo, -stinxi, -stinctum, 3., to separate, divide, distinguish),


distinguitur 'it is distinguished' (present indicative passive third person singular of distinguo)


distinguntur 'they are distinguished' (present indicative passive third person plural of distinguo)


distinctus,-a,-um 'distinct' (an adjective related to the verb distinguo),


diversus,-a,-um 'different, opposed' (past participle (passive??) of diverto, -verti, 3. to turn away, to diverge from, to differ).


removendus,-a,-um 'to be removed or taken away' (gerundive of removeo, -movi, -motum, 2., to remove, put away, take away)



Verbs of more vehemence that an author may wish to use include:


abhorret 'it recedes from' (present indicative active third person singular of abhorreo, 3., to shrink back from, to be opposed to)


distrahit, 'it is estranged' (present indicative active third person singular of distraho,-traxi,-tractum, 3. 'to pull apart, tear asunder, tear in pieces; to estrange'


This last verb has been used by Bentham and Hooker to refer to large, unwieldy genera stuffed with species that should be synonymized or segregated into other existing genera or new genera established to accommodate them: the genus should be 'torn to pieces": genus distrahendum.



The following are suitable MODIFIERS (indeclinable adverbs that may be

 used with the verb forms noted above):


aegre (adv.): scarcely, hardly, with difficulty


statim (adv.) 'immediately, at once' dignoscenda, immediately to be distinguished


praecipue (adv.) 'principally, chiefly'


praesertim (adv.): 'especially'


sine dubio, phrase, without doubt, indisputably; nullo dubio, phrase, without any doubt.


multo (adv.): by much, much


praeterea (adv.) moreover, besides.


bene (adv.): quite, well


praeclare (adv.): very clearly, very well




(Note the epithets are fictitious hence the absence of authority names, which are usually present in the diagnostic Latin text). Authority names, usually abbreviated and never italicized, as is the convention with Latin words, are not declinable: they are not Latin nor, when routinely associated with a species name, do they have any grammatical or syntactic function in a Latin prose sentence.


0 (= undeclined). Muscari  comosum (n) note non-Greek and non-Latin generic names such as Alhagi, Dipcadi, Kali, etc. are not declined: in the dative case they are spelled the same as in the nominative. Such generic names are neuter. Although the generic name may not be declined, the epithet (unless it also is from an alien language) is declined.


Ab Muscari comoso differt, it differs from Muscari comosum.


I. Genista petiolata (f)


Ab Genista petiolata distinguenda, it is to be distinguished from Genista petiolata.


I. Alsine carinata (f)


Ab Alsine carinata recedit, it separates from Alsine carinata.


II. Cytisus magnificus (m)


A Cytiso magnifico differt, it differs from Cytisus magnificus.


II. Spartium versatile (n)


Ab Spartio versatili removendum, [new Spartium species to be removed from Spartium versatile.


NOTE: The noun that 'removendum' modifies here is understood, that is, it is assumed and not written out. In the context presented here, that noun would be the genus Spartium (the new species would be Spartium + epithet). The form of removendum is written with an ending that matches a neuter noun in the nominative singular. Were the genus feminine or masculine, the form would be removenda or removendus respectively.


II. Halimodendron bracteolatum (n)


Ab Halimodendro bracteolato maxime distinctum, most distinct from Halimodendron bracteolatum.


III. Ulex noveboracensis (f)


Ab Ulice noveboracensi sine dubio removenda, from Ulex noveboracensis without doubt to be removed. 


III. Ornithopus subtubulosus (m)


Ab Ornithopode subtubuloso statim recedens, immediately separating from Ornithopus subtubulosus.


III. Leucostoma filiforme (n)


Ab Leucostomate filiformi bene distinctum, quite distinct from Leucostoma filiforme.


 [I know of no genus formulated in the fourth or fifth declension, so have given an example with fructus (IV) and facies (V):]


IV. Semen ab fructu Solani esculenti praecipue discrepans, the seed from the fruit of Solanum esculentum (in genitive singular) is chiefly different


V. Folia ab facie Didmodontis rigiduli distinguntur, leaves from the appearance of Didymodon rigidulus (in genitive singular) are distinguished.




The things (nouns and modifiers of nouns) by which something else is different are in the ablative case (capital letters).


I. Biserrula subaequans (f)


A Biserrula subaequanti HABITU SUFFRUTESCENTE differt, it differs from Biserrula subaequans by its suffrutescent habit.


I. Aeschynomene protrudens (f)


Ab Aeschynomene protrudenti OVARIO SESSILI statim distinguenda, it is immediately to be distinguished from to Aeschynomene protrudens by the sessile ovary.


II. Astragalus panduriformis (m)


Ab Astragalo panduriformi FOLIIS COMPLANATIS recedens, separating from Astragalus panduriformis by its complanate leaves


II. Eremosparton vexillatum (n)


Ab Eremosparto vexillato BRACTEIS LONGIS bene dignoscendum, well distinguished from Eremosparton vexillatum by its long bracts.


III. Hippocrepis mediana (f)


Ab Hippocrepide mediana LEGUMINE SCARIOSO discrepans, different from Hippocrepis mediana by the scarious legume.


[Note the preposition retains its 'b': 'ab' here because the H in Greek words represents only a breathing sound - the actual first letter is the 'i' the succeeds it ('ab' occurs before a vowel).]


III. Fissidens ventricosus (m)


Ab Fissidente ventricoso cellulis inflatis basalibus distinguitur, distinguished from Fissidens ventricosus by the inflated basal cells


III. Physostigma undulatum (n)


Ab Physostigmate undulato petallis rubris multo diversum, much different from Physostigma by the red petals.



Since all families end in -ae (old style) or -aceae (new style), these are plural adjectives treated as nouns. The dative plural always ends in -is for all families:


1. Familia nova Leguminosis fructibus leguminaceis distincta, sed Connaraceis atque Moringeis caulibus brevioribus magis diversa, new family distinct from the Leguminosae by its leguminaceous fruits, but it is more different from the Connaraceae and also the Moringeae by reason of the shorter stems.



0.  Muscari, Muscari (n)


Hoc genus ab Muscari bene differt, this genus (neuter sing.) well differs from Muscari (indeclinable).


I.  Moringa,-ae (f)


Hoc genus ab Moringa removendum, this genus is to be removed from Moringa.


I.  Poecilanthe,-es (f)

Hoc genus ab Poecilanthe praecipue diversum, this genus is chiefly different from Poecilanthe.


I.  Glycine,-es (f.), Galactia,-ae (f.)


Genus a Glycine differt imprimis inflorescentia pauci-foliata, a Galactia apice brevi, ab utroque habitu, the genus differs from Glycine primarily by the few-leaved inflorescence, from Galactia by the short apex, from both by the habit.


II. Drepanocarpus,-i (m)


Genus novum a Drepanocarpo praesertim distinguendum, the new genus is especially to be distinguished from Drepanocarpus.


II. Centrolobium,-i (n)


A Centrolobio corolla bilabiata nullo dubio discrepans, without doubt different from Centrolobium by the bilabiate corolla.


III. Eleocharis,-itis (f)


Ab Eleocharite maxime recedit, from Eleocharis it greatly separates.


III. Nymphoides,-is (f)


A Nymphoide foliis submersis recedens, receding from Nymphoides in its submerged leaves.


III. Actinomyces,-etis (m)


Hoc genus ab Actinomycete distinguitur, this genus is distinguished from the Actinomyces.


III. Pachyphragma,-atis (n)


A Pachyphragmate differt, it differs from Pachyphragma.




1. Subgenus Vignea. (f.)


A subgenere Vignea distinctum, it is distinct from Subgenus Vignea.


II. Subgenus Eubatus (m)


A subgenere Eubato dignoscendum, to be distinguished from Subgenus Eubatus.


III. Subgenus Carex


A subgenere Carice distinguitur, distinguished from Subgenus Carex.




1. Dioicae


Sectio nova a Dioicis praeclare discrepans, new section clearly different from the Dioicae.


II. Sylvatici


Sectio nova a Sylvaticis recedit, new section separates from the Sylvatici.


III. Ovales


Sectio nova ab Ovalibus dignoscenda, new section to be distinguished from the Ovales.


III. Tholiformes


Sectio nova a Tholiformibus maxime distinguitur, new section is mostly distinguished from the Tholiformes.


III. Canadenses


Sectio nova a Canadensibus diversa, new section different from the the Canadenses.



Note: Again, when the subject of the clause or sentence is not stated (i.e. the noun to which the verb form differt, distinguendus etc. refer), the number and gender of the noun modified is often the gender of the new taxon. In the case of new species, it is the number and gender of the genus of which the new species is a member:


Rosa multiflora, sp. nov.  


Ab Rubo laciniato distinguenda, to be distinguished from Rubus laciniatus.     


Paspalum comosum, sp. nov.


A Tritico digitali differt, different from Triticum digitale



Note that in a basic diagnosis the idea that a taxon is similar to another is often stated, as well as similarity to another taxon; adjectives and other modifiers of similarity usually are not associated with a preposition and take their objects in the dative case.


GenistAE petiolatAE similis, sed ab Genista lanceolata differt,SIMILAR TO Genista petiolata but it differs from Genista lanceolata.


The adjective 'similis', it is similar, and other words expressing similarity is associated with no preposition but take their objects in the dative case. In these sentences, clauses and phrases, the taxon name is in the dative case, not the ablative which it would be with the preposition ab (a) and verb forms expressing difference.




The following are some of the English sentences used above for those who might wish to translate them into Latin. The equivalent Latin (i.e. the answers) may be sought in the text above.


It differs from Muscari comosum.


Different from Triticum digitale


It differs from Cytisus magnificus.


What is the Ablative Case ending for second declension singular nouns?


What is the neuter singular form of the comparative of differt?


What is the singular form in the Ablative Case of the participle protrudens?


From Ulex noveboracensis without doubt to be removed.


Most distinct from Halimodendron bracteolatum.


New section mostly distinguished from the Tholiformes.


More different from the Connaraceae and also the Moringeae.


It differs from Biserrula subaequans in its suffrutescent habit.


 In the Latin sentence: New species to be removed from Spartio versatili,  what noun does 'to be removed from' modify?


Keyword: botanical latin