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The validity of naming and describing intraspecific taxa, and the subsequent grouping of such named entities into distinct taxonomic categories, is briefly considered and evaluated. The intraspecific taxonomic categories of aberration, variety, form, race and sub-species are defined and examples given as to their usage. The naming of unique mutants such as sexual and teratological abnormalities, and the means of abbreviated reference to phenotypic clines are also discussed.
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INTRASPECIFIC TAXONOMY IN THE LEPIDOPTERA
J. C. WEIR
32 Paul Drive, Airth, Falkirk, Stirlingshire FK2 8LA
ABSTRACT
The validity of naming and describing intraspecific taxa, and the subsequent
grouping of such named entities into distinct taxonomic categories, is briefly
considered and evaluated. The intraspecific taxonomic categories of aberration,
variety, form, race and sub-species are defined and examples given as to their usage.
The naming of unique mutants such as sexual and teratological abnormalities, and
the means of abbreviated reference to phenotypic clines are also discussed.
INTRODUCTION
Much contention exists regarding the practice of ascribing scientific names to
individuals or groups within a species – so-called infra- or intraspecific names. Both
terms, ‘‘infraspecific’’ and ‘‘intraspecific’’, have been used variously throughout the
literature (e.g. Kloet & Hincks, 1972; Underwood, 2008) and, while both are
acceptable, it is always desirable to have a single term which is universally applied. It
is my opinion that ‘‘intraspecific’’ is preferable given that the Latin prefix ‘‘intra’’
means ‘‘within’’ while ‘‘infra’’ means ‘‘below’’, the former more accurately reflects
the diverse nature of the forms of variation which the different named groups
represent; not merely a single, lower rung on a classificatory hierarchy.
Such names were commonly applied and utilised in the past by entomologists,
particularly those studying the Lepidoptera in the latter part of the nineteenth
century, when volumes such as those of Tutt’s The British Noctuae and their Varieties
(1891; 1892a; 1892b; 1892c) appeared. However, subsequently many have seemingly
abandoned the practice; for example, the Natural History Museum (London) states
that it is ‘‘no longer Museum policy to describe new aberrations of Lepidoptera’’
(NHM, n.d.). Indeed, all intraspecific names, other than sub-species, have been
specifically excluded from the provisions of the International Code on Zoological
Nomenclature (ICZN, 2012), under Article 1.3.4, which might be construed as
official repudiation of the entire concept. Yet, reference is still frequently made to
such names in the entomological literature (e.g. Howarth, 1973; Goater, 1986;
Skinner, 2009).
Given this state of confusion and disagreement, some theoretical reconsideration
of the practice is required. In considering both the necessity and practicality of the
application of intraspecific names, two distinct questions must be addressed, which
are often conflated: (i) the assignation of names to individuals or groups within a
species; and, (ii) the aggregation of these names into discrete taxonomic categories.
(i) Naming Intraspecific Taxa
This would seem to require little defence; naming something allows it to be easily
referred to without constant, lengthy description. This is a crucial consideration for
entomologists dealing with variations which cannot be concisely defined in and of
themselves. However, Edwards (1954) criticised the current conventions of
intraspecific nomenclature arguing that, rather than ascribing variations latinised
scientific names governed by the Law of Priority, they should be ‘‘referred to by
144 BR. J. ENT. NAT. HIST., 29: 2016
vernacular descriptive terminology’’. He suggested, by way of example, the ‘‘’striped
morph’, ’willow morph’ [...]’slender pale morph’’’ or, where the ‘‘morph’’ is
limited in geographical distribution, he suggested that the locality might be
incorporated into the name. He regarded this as the only way to avoid zoological
nomenclature becoming ‘‘overwhelmed by these insignificant minor-category
names’’. While at least implicitly acknowledging the utility of intraspecific naming,
Edwards’s advocacy of the use of vernacular names is a poor one, open to precisely
the same criticisms which might be levelled at the vernacular naming of species; with
no definite type description for reference, nor with a universal language analogous to
Latin, how is anyone to know if the ‘‘striped morph’’ referred to by one author is the
same as the ‘‘forme raye
´e’’ discussed by another. Furthermore, it is not clear that all
variations which might be of interest to entomologists could be referred to in this
manner. How could the aberration of Callophrys rubi (L.) where the white
submarginal spots on the posterior wings are extended and broadened into parallel
streaks (known as ab. radiata Frost under current naming conventions) be described
in a few words? How would one describe ab. infra-pallida Lempke and ab. pallens
Schultz of Aphantopus hyperantus (L.), briefly, in a manner which might easily
differentiate them and prompt universal recognition?
Edwards’s main concern seems to have been that the stringent application of the
Law of Priority to intraspecific names leads to the build up of a morass of useless
synonymy, forever to be enshrined in taxonomic checklists. Unless this was to stop
he foresaw ‘‘confusion [...]overwhelming our nomenclatural machinery’’ and the
‘‘rapid disintegration of intraspecific taxonomy from an orderly regime toward
chaotic proliferation’’. There is some substance to this fear – as lepidopterists in
particular will acknowledge – but it is not an ongoing problem for, where
unnecessarily excessive, these names are primarily the product of a few overzealous
historical collectors. Chaos will ensue, however, if entomologists do not approach
the naming of intraspecific taxa with the same care and scientific seriousness as they
do the naming of species; excessive synonymy is a problem generated by the Law of
Priority only where the practice of description is treated frivolously.
(ii) Classification of Named Intraspecific Taxa
A distinct consideration is that of the grouping of named intraspecific entities into
different taxonomic categories. It is conceivable that, for example, one might name
taxa which represent entirely different forms of variation and make no distinction in
the way in which one refers to them. For instance, there exists a rare form of Pararge
aegeria (L.) called atavica Verity,where the black areas of the wings are reduced in
extent, and a Scottish form named oblita Harrison,where the usually yellowish spots
on the dorsal surface of the wings are white (Verity, 1919; Harrison, 1949). These
could be referred to as trinomials, such as Pararge aegeria atavica and Pararge
aegeria oblita, respectively, or in each case the intraspecific name could be preceded
by a universal, abbreviated designation, such as ‘‘v.’’ (variation). However, this is not
the most desirable practice to adopt for it gives no indication as to the nature of the
variation being described, which differs significantly from an evolutionary
perspective; despite superficial similarities in their attributes, atavica is a rare –
likely deleterious – genetic mutant, while oblita is a locally adapted variation of
limited geographical distribution.
Yet, this pattern of trinomial-reference is one which is seemingly becoming more
and more widespread. As a direct result of the ICZN’s apparent indifference to the
whole subject of intraspecific taxonomy, the use of the term ‘‘sub-species’’ has
BR. J. ENT. NAT. HIST., 29: 2016 145
ballooned into grotesque proportions, a potential problem recognised earlier by
Edwards (1954). Many different populations and groups which it is useful to name
for reference purposes, representing entirely different forms of variation, are
inappropriately assigned sub-specific status due to official recognition of this
taxonomic category alone. Dennis (1977), for instance, describes all variants of
British butterflies limited in geographical extent as sub-species, despite the fact that
the degree of divergence displayed by them varies dramatically – not all can be said
to be incipient species, as is implied by ‘‘sub-species’’.
Where this is not the case and terms traditionally used by lepidopterists such as
‘‘form’’, ‘‘aberration’’ and ‘‘race’’ are employed, their use is highly inconsistent
(Askew, 1970). Skinner (2009), for example, defines the term ‘‘form’’ as ‘‘synonymous
with aberration [denoting] a variety which predominates in part or throughout the
range of the species’’. Ford (1953), however, used the term ‘‘form’’ to describe a
population of a sub-species which may ‘‘be distinguished from the others by constant
features’’ and that might be considered an evolutionarily ‘‘potential sub-species’’, a
concept which Askew himself would have understood as a ‘‘race’’ and Tutt and
Wheeler (1910–14) as a ‘‘variety’’. This is a deeply unsatisfactory state of affairs and
the establishment of, and adherence to, well-defined intraspecific taxonomic
categories would greatly increase the scientific usefulness of the names, as well as
introducing some much needed concision and clarity into entomological discourse.
Proposed Intraspecific Categories
I therefore present the following scheme of categorisation (Table 1). While there is
considerable merit in the intraspecific taxonomy proposed by Askew (1970), it is
overcomplicated in some respects, using unfamiliar terminology and often requiring
prior knowledge as to the genetic or environmental basis of a variation before
appropriate classification. Such information is simply unavailable in most cases. The
following attempts to reconcile practicality and utility in this respect, as well as
maintaining as many traditional definitions and conventions as possible, to minimise
upheaval.
Aberration (ab.) – Individuals within a population which differ morphologically
from the remainder of the population in some discrete respect, being differentiated
from ‘‘varieties’’ in that, while not being unique occurrences, they appear very rarely.
Most aberrations will likely result from homozygosity for a rare recessive allele, such
as Pieris napi ab. hibernica Schmidt where the usual white ground-colour is replaced
on both the dorsal and ventral surfaces by bright yellow. Specimens of the aberration
have only been taken in the wild on a handful of occasions (Ford, 1953) and breeding
experiments have demonstrated its recessive nature (Shepherd, 1942). However,
dominant mutations might also manifest themselves as aberrations, as in Pyronia
tithonus ab. lugens Oberthu
¨r. This is an extremely dramatic aberration which affects
the colouration of an individual to such an extent that it is rendered near-
unrecognisable (Harmer, 2000). Aberrations which are due to dominant alleles are
likely to occur far more rarely and be due mainly to direct mutation given that, if
they are deleterious to an individual’s fitness, dominant alleles are more readily
removed from a population by selection than recessive alleles, which can be
‘‘masked’’ in heterozygotes. In both cases, however, a further advantage to be
derived from assigning aberrations scientific names, governed by the Law of Priority,
is that, where they have a genotypic basis, the same name may be applied to the gene
responsible; thus, we might refer to the lugens and hibernica genes.
146 BR. J. ENT. NAT. HIST., 29: 2016
BR. J. ENT. NAT. HIST., 29: 2016 147
Table 1. Summary of proposed intraspecfic taxonomic categories. Described taxa are classified based on their particular mode of variation – that
is, how the morphologically distinct entity concerned arose within an evolutionary context, such as rare genetic or developmental mutants
(aberrations), seasonal variations (forms), variations limited in geographical extent (races and sub-species), etc.
Taxonomic Category Abbreviation Definition Examples of Application
Aberration
Variety
Form
Race
Sub-species
ab.
var.
f.
r.
ssp.
Individuals morphologically distinct from the remainder of
the population in some discrete respect. Not unique, but
occur rarely in nature, cf. variety.
Group of individuals in a population which share discrete
morphological characteristic/s differing from the remainder
of the population. Occur at frequency too high to be
maintained by recurrent mutation. A polymorphic variant.
A generation/brood, in any given year, morphologically
distinct from the individuals of a different generation in the
same population, in that year. A seasonal variant.
A population composed of
individuals morphologically
distinct from the individuals
of other populations.
Individuals possess a small
number of distinct characters.
Vary in degree and
consistency of distinct
characters.
A potential sub-species.
Individuals possess several
distinct characters. Distinct
characters universal and
consistent.
A potential species.
Pieris napi ab. hibernica
Pyronia tithonus ab. lugens
Boloria euphrosyne ab. edna
Colias croceus var. helice
Noctua comes var. curtisii
Argynnis paphia var. valezina
Pieris napi f. napaeae, f. napi
Pararge aegeria f. aestivalis
Polyommatus icarus r.
mariscolore
Argynnis aglaja r. scotica
Coenonympha tullia r. scotica,
r. davus, r. polydama
Anthocharis cardamines r.
britannica
Anthocharis cardamines ssp.
hibernica
Pararge aegeria ssp. oblita
In addition, aberrations may also be due to the exposure of an individual to
unusual or extreme environmental conditions during its development, sometimes
operating in concert with a particular genetic predisposition. For example, while
melanic individuals of Heliothis peltigera (D. & S.) result from decreased temperature
applied to the pupae (Ford, 1955), the melanic aberration Boloria euphrosyne ab.
edna Lobb is thought to be due to a particular gene which only becomes activated by
high temperatures (Harmer, 2000). The latter situation has been demonstrated by
Kettlewell (1944) in various aberrations of Callimorpha dominula (L.). In all cases,
rarity of frequency is a key characteristic of an aberration.
Variety (var.) – A group of individuals within a population of a species which
share discrete morphological characteristic/s differing from the remainder of the
population of that species, this group generally being a participant in a
polymorphism with several other such groups. Individuals of any particular variety
occur at ‘‘proportions [which] cannot be maintained by recurrent mutation’’ (Ford,
1953),differentiating them from aberrations. The number of varieties comprising a
polymorphism can vary dramatically; for instance, Colias croceus var. helice Hu
¨bner
is a whitish variety, found only among females, which exists in equilibrium with the
typical form alone. In contrast, Noctua comes Hu
¨bner is so variable that there is no
‘‘typical’’ colouration, with Tutt (1892a) listing seven major varieties. Furthermore,
the different varieties which form a polymorphism will often vary geographically in
their relative frequencies, as is the case with N. comes var. curtisii Newman which
makes up a higher proportion of the overall population in Scotland than elsewhere in
Great Britain (Kettlewell, 1973). The olive green variety of the Argynnis paphia (L.)
called var. valezina Esper is, like C. croceus var. helice, an exclusively female form but
it occurs alongside the typical form in varying relative frequencies across the species’
range – from 10 to 0.2% (Ford, 1953). Given that some polymorphic varieties are
practically limited in geographical distribution, it is their distinct and discrete
polychotomous nature within a population which generally differentiates them from
races (that is, there is no smooth gradation of one variant into another within a
population – individuals may be classified with relative ease as either one or the
other). In contrast, within a race, individuals may occur alongside the regionally
adapted variations which more or less closely resemble ‘‘typical’’ individuals.
Form (f.) – The individuals of a particular generation/brood within a population
of a species, in any given year, which differ morphologically from the individuals of a
different generation within the same population in the same year; so-called seasonal
variation. These different forms will often be due to environmental changes, and the
direct effect of the differing conditions upon development. Named examples of this
phenomenon in Great Britain include: Pieris napi f. napaeae Esper and f. napi L.,
which represent the spring and summer broods of this insect, respectively, differing in
the extent and degree of the black wing-markings and the intensity of the yellow
colour on the ventral side; and, Pararge aegeria f. aestivalis Fruhstorfer – the summer
form of this species – which possesses dorsal wing-spots which are reduced in size
and of a somewhat lighter shade. Among species of Lepidoptera from the tropics,
this system would be applied to the variation between the wet- and dry-seasons.
Race (r.) and Sub-species (ssp.) – A population of a species in which the
individuals possess certain characteristics rendering them morphologically distinct
from the individuals of other populations of that species. My concept of these two
taxonomic groups largely agrees with that of Askew (1970). Both the ‘‘race’’ and the
148 BR. J. ENT. NAT. HIST., 29: 2016
‘‘sub-species’’ should be viewed as categories describing the same phenomenon –
geographical divergence based upon local adaptation – the distinction being one of
degree (Fig. 1). Thus, the characteristics used to define or separate races will be fewer
or more subtle than those used to describe a sub-species. It might appear superfluous
to divide named entities, which vary in the same manner (i.e. geographically),
between two different groupings, but in practice this is highly necessary if an overuse
of the term ‘‘sub-species’’ is to be avoided. It is an attempt to solve the problem of
delineating where the sub-species begins by reserving ‘‘the taxon subspecies [...]
only for populations apparently just falling short of representing good species’’
(Askew, 1970). This stands in contrast to the adoption of arbitrary DNA sequence
percentage-difference rules, where a number is plucked from the air to represent how
genetically distinct a population must be before it might be regarded as a sub-species.
The term ‘‘race’’ can therefore be applied to less distinct geographical variations and
should encompass, as Askew (1970) argues, ‘‘isolated, allopatric populations
consisting of a high percentage of a distinctive form, together with other individuals
which are typical [ . . . ]. Whilst the presence of the form indicates that the gene pool
of the [population] is distinctive, the continued presence of typical individuals would
BR. J. ENT. NAT. HIST., 29: 2016 149
Fig. 1. Geographical variation in an hypothetical British species of Lepidoptera. The coloured
circles represent individual insects and their respective morphologies, taken in samples from
various parts of this species’ northern British range. Individuals of the ‘‘typical’’ colouration
(that displayed by the species throughout the greater part of its distribution) are distributed in
the grained area. Typical specimens are pale grey in colour, as shown in sample (c). The
diagonally shaded area represents the distribution of a geographical variation, examples of
which are shown in sample (b). These insects are generally of a slightly different colouration to
that of typical individuals, though they vary in both the consistency and degree of distinctness;
occasionally individuals may occur in this population which greatly resemble typicals. However,
when taken as a whole, this geographically limited population forms a quite distinct grouping
which would be categorised as a race. The vertically shaded area represents the distribution of
another geographically limited variation which, although a member of the same species, is
consistently distinct to a significant degree, as in sample (a). Hence, this would be categorised as
asub-species. Give sufficient time, the action of natural selection and genetic drift may increase
the phenotypic divergence between the typicals and race (b), such that the latter would then be
better considered a sub-species.
suggest the probability of rapid hybridisation with a typical population should the
two become sympatric. It would therefore seem unwise to give a population sub-
specific status so long as typical individuals are present at a frequency which
indicates that they are not merely sporadic variants.’’
It is obvious that there is a degree of subjectivity in this classification, but this is so
with all taxonomy; the question of where one species ends and another begins is no
less complex, nor any less significant, than limits of sub-species and races. These
categories mark important steps in a continuum from total genetic interchange and
uniformity to complete distinction and divergence – and are thus necessary for
describing biological reality – though none can be precisely delimited.
Given the inherent complexity of this, it is my opinion that the categories of race
and sub-species are the most likely to be misunderstood or misused. Therefore, below
I have included several specific examples from the British fauna which I hope will
illustrate this continuum of divergence and give a clearer idea of how these categories
ought to be used if they are to relate a scientifically informative distinction.
The geographical variant of Polyommatus icarus (Rottemburg) referred to as
mariscolore Kane occurs in Ireland, and is distinct in that it is larger and the female
possesses much expanded blue markings on the dorsal wing surface and exaggerated
sub-marginal orange lunules (Ford, 1953; Howarth, 1973; Dennis, 1977). It is found
widely in Ireland, though the diagnostic characteristics are said to vary from a
reduced state to very extreme expression (Lipscomb, 1963; Dennis, 1977). However,
the description also appears to apply to many populations in the Hebrides,
Northumberland and Durham, though once again variation is observed between
individual populations (Heslop-Harrison, 1953; Dennis, 1977, Riley, 2007). The
variation Argynnis aglaja (L.) named scotica Watkins is strikingly similar to
mariscolore in its disposition. It is widely distributed throughout the Outer and Inner
Hebrides and has a larger wingspan, darker green ventral colouration and is overall
far more heavily marked (Watkins, 1923). Populations which inhabit different
islands vary considerably in the degree to which they express scotica characteristics,
and it is reputed that on the Isle of Rhum populations of both typical aglaja and
scotica fly, with intermediates (Ford, 1953). Furthermore, as with mariscolore, scotica
has been recorded from woodlands in Northumberland and Durham (Dennis, 1977).
Despite both of these taxa being regarded by many authorities as sub-species (e.g.
Howarth, 1973; Dennis, 1977), the evidence presented here would seem to suggest a
lesser degree of geographical divergence; in both instances it appears that, taken
overall, a morphologically distinct western/north-western metapopulation does exist,
though there is a considerable degree of variation between the constituent
populations. This is perhaps suggestive of only limited local adaptation, of natural
selection tending to drive populations in this geographical area toward a common
phenotypic response, but not of an historically (or currently) isolated, genetically
distinct population, almost representing a distinct species. Hence, on current
evidence, these these two intraspecific taxa would better be regarded as races;
Polyommatus icarus r. mariscolore and Argynnis aglaja r. scotica.
Equally, the different geographic variants of Coenonympha tullia Mu
¨ller, often
referred to as sub-species (e.g. Riley, 2007; Thomas & Lewington, 2010), would be
better considered races. While there are reasonable morphological differences
(primarily in the prominence of the eye-spots) between r. scotica Staudinger which
occurs in the Highlands, r. davus F. which occurs in southern Yorkshire and the
surrounding counties, and r. polydama Haworth which is intermediate in distribution
and appearance, it is not uncommon for specimens resembling one population to
occur in another. For instance, Ford (1953) writes that ‘‘[i]t appears that in the
150 BR. J. ENT. NAT. HIST., 29: 2016
island of Islay scotica predominates, but that the intermediate sub-species tullia
[=polydama] is not uncommon and that even specimens closely approaching
philoxenus [=davus] occur’’ and that in Ireland ‘‘[t]he sub-species philoxenus
[=davus] does not occur, but scotica and tullia [=polydama], with their
intermediates, fly together in the same localities.’’ These facts serve to demonstrate
a less distinct degree of evolutionary divergence; that the gene pool of these
populations is less distinct than one might expect of sub-species.
Anthocharis cardamines (L.) represents a particularly interesting situation. It was
originally described from specimens taken in Sweden and those occurring in Great
Britain are said to belong to a distinct sub-species referred to as britannica Verity,
characterised by somewhat elongated anterior wings and the black apical spot being
expanded and ill-defined (Verity, 1908). However, Dennis (1977) notes that these
characters ‘‘deviate only slightly’’ from those of continental individuals and that,
indeed, these characters often occur with equivalent frequencies across many British
and continental populations; even Verity (1908) acknowledged that continental
specimens could often be said to possess these characters. As such, we might
conclude that the British population represented only a slightly divergent
geographical race, rather than a sub-species. In contrast, Irish specimens of
A. cardamines, referable to as hibernica Williams, are smaller and possess expanded
dorsal black markings, the dorsal surface of the female posterior wings is flushed
with orange and the ventral surface of the male anterior wings is tinged with yellow
(Williams, 1916). The endemism of some of these characteristics to the Irish
population has been disputed (Dennis, 1977) and they might initially seem very slight
and indistinct. However, several facts must be borne in mind: even excluding
disputed characteristics, hibernica is more distinct than britannica;A. cardamines
typically shows little inter- and intra-population variation, such that we might expect
any geographical variants to be less distinct that those of other species – that is, the
expectation of distinctness for certain classificatory thresholds (i.e. race, sub-species)
is adjusted based on biological knowledge of the species; and, these characters
are apparently consistent across Ireland. Taken together, these facts might suggest
that hibernica is more evolutionarily divergent than britannica, and warrants true
sub-specific status.
The geographical variant of Pararge aegeria L. referred to as oblita Heslop-
Harrison represents a further example which is best described as a sub-species. It is
distinct in that the wing markings are creamy white as opposed to the typical yellow
or orange, and the overall appearance is one of increased contrast between the black
and white wing markings (Dennis, 1977; Riley, 2007; Thomas & Lewington, 2010). It
is distributed continuously throughout the Hebrides and the north-west of Scotland,
being for the most part isolated from the typical form which occurs in the rest of the
British Isles by large distances (Dennis, 1977; Riley, 2007; Thomas & Lewington,
2010). This suggests that this variant has arisen in isolation and given the stability
and consistency of its derived characteristics across oblita populations it would
appear to represent a strongly morphologically and genetically distinct lineage,
worthy of sub-specific rank.
Thus, geographical variations must be visualised as populations or groups of
populations moving along an axis of differentiation and divergence where, as they
become more distinct, the populations move toward speciation. It ought to be a
guiding taxonomic principle that just as a sub-species should to be considered a
potential species, given sufficient time and the action of evolution, so to a race should
be considered a potential sub-species. As such, the categories of race (weakly
divergent population), sub-species (significantly divergent) and species (completely
BR. J. ENT. NAT. HIST., 29: 2016 151
divergent) are helpful in that when used they convey something of the biological and
evolutionary situation of a particular population/meta-population – an indication of
its position along the pathway to complete, specific divergence.
Sexual and Teratological Abnormalities, etc. – The assignation of scientific names
to sexual abnormalities (such as gynandromorphic or intersex specimens),
teratological aberrants, homeotic mutants, and somatic mosaics deserves special
consideration because it presents particular difficulties to the taxonomist. Under
the category definitions outlined above, such specimens ought to be classed as
aberrations. However, for the most part, these particular aberrations are
morphologically unique, due to the the stochastic nature of the environmental
events which affect post-embryonic / pre-imaginal development, and lead to their
production. In such instances, it is neither scientifically informative nor
taxonomically useful to name these aberrants, for to do so would be to effectively
name an individual specimen. However, it may be that unique aberrants of a
particular sort occur with such frequency that it might be desirable to ascribe a name
to them, collectively – that is, while all individuals of this aberration are strictly
speaking morphologically unique, they all share a common form of aberration.
For example, specimens of Maniola jurtina (L.) are frequently encountered with
patches or ‘‘flushes’’ of pale, almost translucent scales on the wings, which contrast
greatly with the typical deep brown ground-colouration. This is thought to be due to
a developmental defect preventing the scales from forming correctly, and
aberrational names have been coined for this same developmental aberration
occurring in different parts of the wings (Thomson, 1969). There can be little benefit
in naming based on the arbitrary distinction of where the defect occurs, given that
this is entirely due to chance. Therefore, Thomson (1969) proposed that all such
aberrations of this sort be grouped under a single aberrational name – a name to
describe this particular developmental error, if not a precisely morphologically
similar set of specimens. This is the only sense in which I consider it helpful to name
‘‘unique’’ developmental aberrants of this sort, where, although each aberrant
specimen is unlikely to be exactly similar to another, they yet display a common form
of aberration. Similarly, a particular teratological or sexual aberration, such as a
gynandromorph, of a particular morphology might occur with such unusual
frequency that it may be desirable to give it a name for ease of reference.
Clines – ‘‘Cline’’ is a term used to describe the character-gradient generated when a
species varies continuously and gradually across a large area (Ford, 1953). These
gradual changes are brought about by equally gradual changes in environmental
conditions, with the corresponding proportional variation in the action and pressures
of selection. The term, abbreviated to the prefix ‘‘cl.’’, may be used to concisely refer
to any such occurrence, e.g. Coenonympha tullia cl. scotica-davus.
CONCLUSIONS
Scientific intraspecific names, governed by the Law of Priority, are very useful to
those who study the variation and evolution of insect species. This is particularly the
case in the Lepidoptera, where variation in their wing colouration is easily
appreciated and compared. Where ascribed prudently, intraspecific names facilitate
easy and unambiguous reference to a particular variation which has been
taxonomically described in the literature, previously. Furthermore, the classification
of variations into clearly delimited taxonomic categories at the intraspecific level
reflects inherent evolutionary differences, and the abbreviated use of these categories
152 BR. J. ENT. NAT. HIST., 29: 2016
when referring to such variations immediately relates their general nature. While no
such classificatory arrangement is perfect and universally applicable, this is not an
argument against the use of a system which is generally practicable, and it falls to the
individual entomologist to use his discretion in difficult cases and be in full
possession of the facts, as far as possible, before venturing to publish any
descriptions. In addition, there is no outstanding reason why this arrangement
could not be applied to other groups of organisms with only minor adjustments.
ACKNOWLEDGEMENTS
I am greatly indebted to Dr Matthew Bell of the Institute of Evolutionary Biology,
University of Edinburgh, for offering his thoughts on several early drafts of this
paper. Also I should like to thank the Editor, John Badmin, for making many
constructive and thought-provoking suggestions.
REFERENCES
Askew, R. R. 1970. Infraspecific categories in insects. Biological Journal of the Linnean Society
2: 225 –231.
Dennis, R. L. H. 1977. The British Butterflies: Their Origin and Establishment. Faringdon, E. W.
Classey Ltd.
Edwards, J. G. 1954. A new approach to infraspecific categories. Systematic Biology 3: 1–20.
Ford, E. B. 1953. Butterflies. London,Collins.
Ford, E. B. 1955. Moths. London, Collins.
Goater, B. 1986. British Pyralid Moths: a guide to their identification. Colchester,Harley Books.
Harmer, A. S. 2000. Variation in British Butterflies. Lymington,Paphia Publishing Ltd.
Harrison-Heslop, J. W. 1953. Polyommatus icarus, Rott., double brooded in Durham.
Entomologist 86: 18.
Howarth, T. G. 1973. Colour Identification Guide to Butterflies of the British Isles. London,
Frederick Warne Ltd.
ICZN, 2012. The International Code of Zoological Nomenclature. [online] Available at: http://
www.iczn.org/code [Accessed 15 February 2016].
Kettlewell, H. B. D. 1944. Temperature effects on the pupae of Panaxia dominula L.
Proceedings of the South London Entomological and Natural History Society 1943–4: 79–81.
Kettlewell, H. B. D. 1973. The Evolution of Melanism. London, Oxford University Press.
Kloet, G. S. & Hincks, W. D. 1972. A Check List of British Insects: Part 2 Lepidoptera. London,
Royal Entomological Society.
Lipscomb, C. G. 1963. From machaon to icarus.Entomologist’s Record and Journal of Variation
75: 215–217.
NHM, n.d. Notes on the Database (Rothschild Cockayne Kettlewell Collection). [online]
Available at: http://nhm.ac.uk/research-curation/scientific-resources/biodiversity/
uk-biodiversity/cockayne/notes/index.html [Accessed 12 August 2015].
Riley, A. M. 2007. British and Irish Butterflies. Luton, Brambleby Books.
Shepherd, J. 1942. Breeding experiments with the Irish yellow race of Pieris napi.Entomologist
75: 233–235.
Skinner, B. 2009. Colour Identification Guide to the Moths of the British Isles. Stenstrup,
Denmark, Apollo Books.
Thomas, J. & Lewington, R. 2010. The Butterflies of Britain and Ireland. Dorset, British Wildlife
Publishing Ltd.
Thomson, G. 1969. Maniola (Epinephele)jurtina (L.) and its forms. Entomologist’s Record 81:
7–14.
Tutt, J. W. 1891. The British Noctuae and Their Varieties. Volume I. London, Swan,
Sonnenschein & Co.
Tutt, J. W. 1892a. The British Noctuae and Their Varieties. Volume II. London, Swan,
Sonnenschein & Co.
Tutt, J. W. 1892b. The British Noctuae and Their Varieties. Volume III. London, Swan,
Sonnenschein & Co.
BR. J. ENT. NAT. HIST., 29: 2016 153
Tutt, J. W. 1892c. The British Noctuae and Their Varieties. Volume IV. London, Swan,
Sonnenschein & Co.
Tutt, J. W. & Wheeler, G. 1910–14. A Natural History of the British Butterflies: Their World-
Wide Variation and Geographical Distribution. London, Elliot Stock.
Underwood, D. L. A. 2008. Intraspecific variability in host plant quality and ovipositional
preferences in Eucheira socialis. Ecological Entomology 19: 245–256.
Verity, R. 1908. Rhopalocera Palaearctica, Iconographie et Description des Papillons diurnes de
la re
´gion pale
´arctique: Papilionidae et Pieridae. Florence, R. Verity.
Watkins, T. H. G. 1923. A new Argynnis race. Entomologist 56: 108.
Williams, H. B. 1916. Notes on the life-history and variation of Euchloe cardamines L.
Transactions of the London Natural History Society 1916: 62–84.
SHORT COMMUNICATIONS
Some Hemiptera new to Kent from Greenwich Park. – Survey work in Greenwich
Park, West Kent (VC16) in 2016 yielded some interesting bug species, some of which
appear to be the first records for Kent.
On the 5th July, I beat several Turkey Oaks Quercus cerris and was rewarded with
large numbers of the mirids Psallus anaemicus Seidenstu
¨cker, Psallus helenae Josifov
on trees in the deer park (TQ395770) and both were also frequent in the north of the
Park (TQ389774) where I also took a single female of Psallus lucanicus Wagner. All
three have recently been added to the British list and are likely to be widespread.
I also took P. anaemicus in Surrey and North Hampshire in 2016.
On 30th August I beat several adult Arocatus longiceps Spinola (Lygaeidae), from
various trees including Holm Oak Q. ilex, and found two more under bark of a dead
standing oak. Although now widespread in Greater London on Plane trees, these
may be the first county records.
An ornamental golden variety of Lawson’s Cypress Chamaecyparis lawsoniana in
the gardens supported large numbers of adults of the cicadellid hopper Liguropia
juniperi Lethierry, which is spreading rapidly (already breeding in Oxfordshire) and is
likely to be widespread in Kent, but these maybe the first published record for the county.
ACKNOWLEDGEMENTS
Thanks to Royal Parks for supporting this survey work, and especially to Sam
Wilkinson for organising access. – JONTY DENTON, 31 Thorn Lane, Four Marks,
Hants GU34 5BX.
Phryganea grandis L. (Trichoptera: Phryganeidae) in north Kent. – A specimen of
our largest UK caddisfly P.grandis (see BJENH 28: Plate 7) appeared in one of the
light-traps operated on a Bat and Moth evening organised at the Gunpowder Works,
Faversham (TR002624) on the night of 24th July 2016. Although a widespread
species in the UK (Barnard & Ross, 2012), there are few records from Kent. The
specimen, which probably represents an emergent from the nearby lakes, is the 8th
record for north Kent and the 16th for the entire county (Tony Witts, pers.comm.). If
so, it was lucky to have missed the patrolling Daubenton’s bats Myotis daubentonii
(Kuhl) which we observed by torch light skimming low over large areas of the main
fishing lake. – JOHN BADMIN, Coppice Place, Selling, Kent ME13 9RP.
REFERENCE
Barnard, P. & Ross, E. 2012. The adult Trichoptera (caddisflies) of Britain and Ireland.
Handbooks for the Identification of British Insects Vol. 1 Part 17.
154 BR. J. ENT. NAT. HIST., 29: 2016
... Taxonomy and nomenclature below species level has been an area of considerable debate (e.g. Edwards, 1954) and variants which occur as part of a balanced polymorphism, of the kind which might be maintained by apostatic selection, represent only one of a range of within-species groups to which names and descriptions are typically ascribed (reviewed in Weir, 2016). In some groups, names have been applied to morphs which represent merely arbitrary stages in a continuously varying trait. ...
... The intraspecific taxa described by Tutt (1891-92), which he referred to as 'varieties', do indeed primarily represent true polymorphic forms which co-occur throughout the distribution of a species. However, Turner (1925-26) lists only 'races' (geographical variants, see Weir, 2016) and 'aberrations', the latter encompassing both the participant forms in balanced polymorphisms and named but very rare developmental and genetic mutants. Both are therefore likely to give a reliable estimation of the degree of polymorphic variability of a given species, although data obtained from Turner (1925-26) may have over-estimated this and should be treated with caution. ...
... However, in both monographic treatments of intraspecific variation utilized as sources of information, the morphs described are generally common, widespread and co-occurring. It is not typical practice to name unique mutants, and forms with limited geographical distribution would be designated 'races' (Weir, 2016); these were not included in the analyses. This explanation of the correlation is therefore unlikely and, furthermore, cannot explain the absence of a correlation in the remaining groups, which too display great variation in abundance. ...
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Phenotypic polymorphism in cryptic species is widespread. This may evolve in response to search image use by predators exerting negative frequency‐dependent selection on intraspecific colour morphs, “apostatic selection”. Evidence exists to indicate search image formation by predators and apostatic selection operating on wild prey populations, though not to demonstrate search image use directly resulting in apostatic selection. The present study attempted to address this deficiency, using British Lepidoptera active in winter as a model system. It has been proposed that the typically polymorphic wing colouration of these species represents an anti‐search image adaptation against birds. To test (a) for search image driven apostatic selection, dimorphic populations of artificial moth‐like models were established in woodland at varying relative morph frequencies and exposed to predation by natural populations of birds. In addition, to test (b) whether abundance and degree of polymorphism are correlated across British winter‐active moths, as predicted where search image use drives apostatic selection, a series of phylogenetic comparative analyses were conducted. There was a positive relationship between artificial morph frequency and probability of predation, consistent with birds utilising search images and exerting apostatic selection. Abundance and degree of polymorphism were found to be positively correlated across British Lepidoptera active in winter, though not across all taxonomic groups analysed. This evidence is consistent with polymorphism in this group having evolved in response to search image driven apostatic selection and supports the viability of this mechanism as a means by which phenotypic and genetic variation may be maintained in natural populations. This article is protected by copyright. All rights reserved.
... Image: Lichen glaucus © The Linnean Society of London diff erent types of within-species variants. I have proposed the resurrec� on of the term "race", once used commonly by entomologists, for weakly divergent popula� ons of the kind illustrated by C. tullia (Weir 2016). Similarly, Mr Okon eloquently illustrates the absurdity of calling what is plainly a polymorphic variety of Zoila marginata, of limited geographical distribu� on, a sub-species. ...
... I believe that with a broader range of categories, that could be specifi ed with prefi xes to the formal names, so much more biological informa� on could be conveyed: dis� nc� on could be made at a glance between weakly or strongly divergent geographical popula� ons; polymorphic varie� es; seasonal forms; rare mutants; and, so on. I have argued this case at some length previously (Weir 2016). ...
... Taxonomy and nomenclature below species level has been an area of considerable debate (e.g. Edwards, 1954) and variants which occur as part of a balanced polymorphism, of the kind which might be maintained by apostatic selection, represent only one of a range of within-species groups to which names and descriptions are typically ascribed (reviewed in Weir, 2016). In some groups, names have been applied to morphs which represent merely arbitrary stages in a continuously varying trait. ...
... However, in both monographic treatments of intraspecific variation utilized as sources of information, the morphs described are generally common, widespread and co-occurring. It is not typical practice to name unique mutants, and forms with limited geographical distribution would be designated 'races' (Weir, 2016); these were not included in the analyses. This explanation of the correlation is therefore unlikely and, furthermore, cannot explain the absence of a correlation in the remaining groups, which too display great variation in abundance. ...
Thesis
Paradoxically, many species which rely upon crypsis to avoid predation also display considerable colour polymorphism. It has been argued that this has evolved in response to the use of "searching images" by foraging predators. Searching images result from a predator encountering a prey item and undergoing a process of learning, recalling the appearance of that prey item in order to increase its chances of detecting it again. However, this occurs at the cost of failing to perceive other alternative prey items. Thus, predators which hunt using searching images exert a form of negative frequency-dependent selection on prey populations, where rare colour morphs are at a selective advantage because they do not match the searching image typically adopted. It has specifically been hypothesised that this mechanism has resulted in the evolution of colour polymorphism in those species of nocturnal British Lepidoptera active during the winter months. This study considered whether searching image use results in negative frequency-dependent selection in natural populations, using the British winter-active Lepidoptera as a study system. In a series of field experiments (Part I), artificial dimorphic populations of moth-like models were established, and the frequency at which either morph occurred was varied. It was found that birds predating these models exerted negative frequency-dependent selection on the populations, indicative of searching image use. In addition, a series of phylogenetic comparative analyses were carried out (Part II) to test the theoretical expectation that, where searching image use results in negative frequency-dependent selection, abundance and the degree of polymorphism ought to be positively correlated across prey species. This expectation was confirmed in British winter-active Lepidoptera, though only in some groups of non-winter-active Lepidoptera. It was concluded that this evidence was consistent with birds using searching images to hunt British winter-active moths, and hence exerting negative frequency-dependent selection on their populations, resulting in the evolution and maintenance of colour polymorphism in these species. Searching image use by predators is therefore suggested to represent a viable mechanism by which genetic and phenotypic variation might be maintained in nature.
... 7: pl. 1 fig. 3. Locus typicus: "Europa" [incompertus].Irodalom -References:Alford 1992;Bodor et al. 2011;Diakonoff 1986;De Prins et al. 2014;Erdős 1971;Fazekas 2014Fazekas , 2015Fazekas & Schmidt 2016;Fialowski 1902;Gozmány 1955;Rota et al. 2014; Schmidt 2010; Szabóky 2015;Szeőke & Csóka 2012;Weir 2016; Wirth et al. 2020. ...
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A Stenomesius rufescens (Retzius, 1783) a Choreutis nemorana (Hübner, 1799) parazitája Magyarországon (Hymenoptera, Lepidoptera) Stenomesius rufescens (Retzius, 1783), a parasite of Choreutis nemorana (Hübner, 1799) in Hungary (Hymenoptera, Lepidoptera) Fazekas Imre Abstract. Stenomesius rufescens (Retzius, 1783) [Hymenoptera, Eulophidae] has long been known in Hungary but is very rare and local. The locations of the species are shown by a map. It is known in the Pannonian Region mainly in the hills (200-500 m). The imagines were collected from May to early November. The study presents the diagnosis of the species, its bionomy, its distribution in Hungary and its geographical distribution. The author reports the moth species parasitized by Stenomesius rufescens: Anania verbascalis ([Denis & Schiffermüller 1775); Ca-loptilia azaleella (Brant, 1813); Chilo suppressalis (Wlaker, 1863); Cnephasia longana Ha-worth, 1811, Ectoedemia argyropeza Zeller, 1839; Helicoverpa armigera (Hübner, 1808); Lyo-netia clerkella Linnaeus, 1758; Stigmella aurella (Fabricius, 1775). The species was bred from larvae of Choreutis nemorana (Hübner, 1799). This is the first record of breeding from Hungary. Each larva contained several Stenomesius rufescens parasites. Over the past decade, Choreutis nemorana has been expanding rapidly in Hungary. Many fig trees show the distinctive feeding pattern of the larvae. The author has been studying fig trees for many years, especially in the Mecsek Mountains in southern Hungary. He had previously recorded a fig wasp (Blastophaga psenes Linnaeus, 1758) native to the Mediterranean and established in the Mecsek Mountains. The mountains cover an area of approximately 500 km². The highest peak in the mountain range is Zengő , which has an elevation of 682 metres. The climate is sub-Mediterranean. The figs have been cultivated in the mountains for about two thousand years. Choreutis nemorana, Stenomesius rufescens and Blastophaga psenes probably live here in the mountains, but so far no one has studied their distribution here.
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We present a genome assembly from an individual female Maniola jurtina (the meadow brown; Arthropoda; Insecta; Lepidoptera; Nymphalidae). The genome sequence is 402 megabases in span. The complete assembly is scaffolded into 30 chromosomal pseudomolecules, with the W and Z sex chromosome assembled. Gene annotation of this assembly on Ensembl has identified 12,502 protein coding genes.
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Article
. 1This study investigates interactions between Eucheira socialis (Pieridae: Lepidoptera), a strict monophagous herbivore, on Arbutus xalapensis (Ericaceae), a host plant with few herbivores. This tight association of insect on plant has many attributes conducive to reciprocal rather than diffuse evolution.2An indirect way of testing plant–insect coevolutionary theories is to test for the necessary conditions for reciprocal evolution in ecological time. Two conditions for coevolution were studied: (1) host plants vary in their suitability for larval growth and development, and (2) ovipositing insects discriminate among these plants based on their relative suitability.3Large differences in host plant suitability were found and relative differences were consistent from year to year.4There was no evidence that female insects based their ovipositional decisions on relative tree quality, which implies that factors other than host plant quality are involved in the maintenance and evolution of oviposition behaviour in Eucheira.5Of seven factors known to influence ovipositional preferences of insects among plants independent of potential larval success, the most likely causal factor in this system is the ability of females to balance a time/energy budget for finding potential oviposition sites, discriminating among them, and actually ovipositing.
British Pyralid Moths: a guide to their identification
  • J G Edwards
Edwards, J. G. 1954. A new approach to infraspecific categories. Systematic Biology 3: 1-20. Ford, E. B. 1953. Butterflies. London, Collins. Ford, E. B. 1955. Moths. London, Collins. Goater, B. 1986. British Pyralid Moths: a guide to their identification. Colchester, Harley Books.
Variation in British Butterflies
  • A S Harmer
Harmer, A. S. 2000. Variation in British Butterflies. Lymington, Paphia Publishing Ltd.
  • J W Harrison-Heslop
Harrison-Heslop, J. W. 1953. Polyommatus icarus, Rott., double brooded in Durham. Entomologist 86: 18.
Colour Identification Guide to Butterflies of the British Isles
  • T G Howarth
Howarth, T. G. 1973. Colour Identification Guide to Butterflies of the British Isles. London, Frederick Warne Ltd.