A rose by any other name?
A new EPN and its associated bacteria named and described for South Africa:
Heterorhabditis noenieputensis and Photorhabdus luminescens subsp. noenieputensis
E
ntomophilic, which literally means ‘insect-
took a soil sample underneath a
loving’, has previously been used to de-
garden fig tree on their farm which
scribe nematodes associated with insects. As
is close to Noenieput, which seems
nematodes are often parasites of insects that
to be located in the middle of no-
lead to the death of the insects concerned, the
where (Fig. 1 right). The soil was
name entomophilic seems bizarrely inappro-
trapped with insects at the Depart-
priate. The descriptor for these nematodes was
ment of Conservation Ecology and
changed to ‘entomogenous’, in an attempt to
Entomology at Stellenbosch Uni-
include the parasitic nematodes within the
versity for the presence of EPN,
nomenclature. This term, which is generally
and, surprisingly enough, a new
used in Mycology, means ‘growing on insects’.
species of insect pathogenic nema-
Later, the term ‘entomoparasitic’ was used to
tode was discovered. Not only was
describe the parasitic nematodes. However,
the nematode new to science, but
as, in the case of steinernematids and heter-
so, too, were the symbiotic bacte-
orhabditids, they kill the insect by transmit-
ria associated with it.
Antoinette Malan
Fig. 1. Origin of Heterorhabditis noenieputensis, at the
settlement of Noenieput close to the Namibian border.
ting a disease, rather than killing the insect
During the process of describing this
During the study of the nematode and its
directly themselves, the term ‘entomopatho-
new species, it seemed fit to give it the im-
associated bacteria, an interesting phenom-
genic nematodes’ has been adopted as the
pressive name of Heterorhabditis noenie-
enon was found to occur, notably that, when
appropriate descriptor. The acronym for this
putensis. Overseas reviewers of the scientific
an insect is infected with the nematode, the
name, i.e. EPN, has been universally adopted
paper expressed their dissatisfaction with the
bacteria cause it to glow in the dark. Biolumi-
to refer to the nematodes involved (Nguyen &
name, as they found it to be unpronounce-
nescence is the production of light by a living
Hunt, 2007).
able, but, despite such negative criticism, the
organism and refer to in the ‘luminescens’
Few people may, as yet, have heard of
paper was published with the name as such.
part of the name of the bacterium. This bio-
Noenieput, a little settlement in the North-
The symbiotic bacteria associated with the
luminescence can only be observed with the
ern Cape Province, close to the south-east-
nematode were then described in collabora-
naked eye after sitting in absolute darkness
ern portion of the Namibian border. Elma
tion with the Department of Microbiology,
for a length of time, or by means of a special
Carstens, of Citrus Research International,
and, so as to ease up on the situation, the
microscope (Fig. 2, left).
scientific name of Pho-
To conclude, even though the nature of
torhabdus luminescens
things is more important than what they are
subsp. noenieputensis
called, in the case EPN and our new nema-
was given.
tode, naming is also of extreme importance.
References
Fig. 2. A. Nematode and bacteria infected wax moth larvae as seen
with the naked eye. B. The same larvae photographed by a special
microscope, showing their glow in the dark capability.
(Photo: The IVIS bioluminescence and fluorescence in vivo imaging
system of the Department of Microbiology).
TECHNOLOGY
Ferreira, T., Van Reenen, C., Pagès, S., Tailliez, P., Malan, A.P., & Dicks, L. 2013. Description
of Photorhabdus luminescens subsp. noenieputensis subsp. nov., a symbiotic bacterium associated
with a new Heterorhabditis species related to Heterorhabditis indica. International Journal of Systematic and Evolutionary Microbiology, 63: 1853-1858.
Malan, A.P., Knoetze, R. & Tiedt, L.R. 2014. Heterorhabditis noenieputensis n. sp. (Rhabditida:
Heterorhabditidae), a new entomopathogenic nematode from South Africa. Journal of Helminthology, 88(2): 138-151.
Nguyen, K.B. & Hunt, D.J. 2007. Entomopathogenic Nematodes: Systematics, Phylogeny and Bacterial Symbionts. Brill Leiden-Boston.
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