A new species of alien terrestrial planarian in Spain: Caenoplana decolorata

Abstract

Terrestrial planarians found in a plant nursery in Spain in 2012 are described as a new species, Caenoplana decolorata. Dorsally they are mahogany brown with a cream median line. Ventrally they are pastel turquoise fading to brown laterally. Molecular data indicate that they are a member of the genus Caenoplana, but that they differ from other Caenoplana species found in Europe. One mature specimen has been partially sectioned, and the musculature and copulatory apparatus is described, confirming the generic placement but distinguishing the species from other members of the genus. It is probable that the species originates from Australia.

Full text

A new species of alien terrestrial planarian
in Spain: Caenoplana decolorata
Eduardo Mateos
1
, Hugh D. Jones
2
, Marta Riutort
3
and
Marta Álvarez-Presas
3,4
1Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals. Facultat de Biologia,
Universitat de Barcelona, Barcelona, Spain
2Life Sciences Department, Natural History Museum, London, UK
3Departament de Genètica, Microbiologia i Estadística. Facultat de Biologia, Universitat de
Barcelona, Barcelona, Spain
4School of Biological Sciences, University of Bristol, Bristol, UK
ABSTRACT
Terrestrial planarians found in a plant nursery in Spain in 2012 are described as a
new species, Caenoplana decolorata. Dorsally they are mahogany brown with a
cream median line. Ventrally they are pastel turquoise fading to brown laterally.
Molecular data indicate that they are a member of the genus Caenoplana, but that
they differ from other Caenoplana species found in Europe. One mature specimen
has been partially sectioned, and the musculature and copulatory apparatus is
described, confirming the generic placement but distinguishing the species from
other members of the genus. It is probable that the species originates from Australia.
Subjects Biodiversity, Molecular Biology, Taxonomy, Zoology
Keywords Molecular identification, Alien species, Invasive species, Land flatworm
INTRODUCTION
Álvarez-Presas et al. (2014) recorded several terrestrial planarian species from Spain, some
considered native to Europe, others introduced from other continents. Some species were
identifiable on the basis of external features such as colour and shape, on anatomical
characters and comparative molecular analysis. Molecular results suggested that further
species were found but at the time they could not be certainly identified to species,
though perhaps to genus. This paper describes specimens (Figs. 1A–1D) listed as
‘Caenoplana Ca2’by Álvarez-Presas et al. (2014). Molecular data (Fig. 12 of Álvarez-Presas
et al., 2014) indicate that these specimens are of the genus Caenoplana Moseley, 1877,
but distinct from other Caenoplana species. One mature specimen has been partially
sectioned, and the musculature and copulatory apparatus is described. It has the characters
of the genus Caenoplana Moseley, 1877, as amended by Ogren & Kawakatsu (1991)
and by Winsor (1991) but differs from other described species of that genus both in
external characteristics and anatomy. Neither do the specimens resemble any species
described only on external features such as shape and colour and currently placed in the
genus Australopacifica Ogren & Kawakatsu, 1991, a collective genus containing species
‘not classifiable into the present taxonomic genera because of insufficient morphological
information; geographical distribution largely in Australasia and Indo-Pacific Islands.
How to cite this article Mateos E, Jones HD, Riutort M, Álvarez-Presas M. 2020. A new species of alien terrestrial planarian in Spain:
Caenoplana decolorata.PeerJ 8:e10013 DOI 10.7717/peerj.10013
Submitted 28 July 2020
Accepted 1 September 2020
Published 2 October 2020
Corresponding author
Eduardo Mateos, emateos@ub.edu
Academic editor
Jean-Lou Justine
Additional Information and
Declarations can be found on
page 12
DOI 10.7717/peerj.10013
Copyright
2020 Mateos et al.
Distributed under
Creative Commons CC-BY 4.0

A collective group for species inquirendae and nomina dubia’. It is described as
Caenoplana decolorata sp. nov.
METHODS
Sampling
Specimens were collected by E. Mateos from a plant nursery named “vivers casa Paraire”
in Bordils municipality (Girona province, Spain, WGS84, position: 42.0348N; 2.8986E).
All were collected by hand from beneath pots (Figs. 1E and 1F) that contained the
Figure 1 Caenoplana decolorata sp. nov. (A–D) Photographs of live specimens, anterior to the right.
(A) Dorsal view of specimen PT426 showing the ‘mahogany brown’colour and ‘cream’median line. Scale
bar 10 mm. (B) A twisted specimen PT657-1 showing the ‘pastel turquoise’ventral surface. Scale bar
10 mm. (C) Specimen PT657-1 and (D) specimen PT426, anterior end showing anterior ‘copper brown’
colour and the eyes (the two white lines in (D) are reflections from the lighting). Scale bars 4 mm.
(E and F) Pots under which the specimens were found, in a greenhouse (E) and outdoors (F).
Full-size
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DOI: 10.7717/peerj.10013/fig-1
Mateos et al. (2020), PeerJ, DOI 10.7717/peerj.10013 2/15

plants on 12 January 2012 (five specimens: PT426, PT427, PT428, PT430, PT431) and
22 October 2012 (four specimens: PT655, PT657-1, 2 and 3) (Table 1).
Specimens from 12 January 2012 and specimens PT655 and PT657-3 were preserved
in absolute ethanol for further molecular analyses. Specimens PT657-1 and 2 were killed
with boiling water, fixed with 10% formalin and preserved in 70% ethanol. Specimens
PT426 and PT657-1 were photographed alive (Fig. 1).
Molecular methods
All the sequences used in the present work were obtained in previous studies with the
exception of some Cytochrome Oxidase I (herein Cox1) sequences that were obtained from
individuals collected at the Real Jardín Botánico de Córdoba (Spain) by Mónica López
(Table 1). In all cases, a small section of the anterior end of specimens preserved in absolute
ethanol was used for DNA extraction. The new sequences were obtained following the
same protocol as in Álvarez-Presas et al. (2014).
A nucleotide alignment was obtained for the Cox1 sequences based on the AA
translation as a guide using BioEdit software (Hall, 1999) and the echinoderm
mitochondrial genetic code (9). A Maximum Likelihood (ML) phylogeny was inferred
using the IQtree software (Nguyen et al., 2015) with the MFP+MERGE implementation
and 10,000 replicates for ultrafast bootstrap search (-bb option). Then two single locus
molecular species delimitation methods were applied in order to check the validity of
the new species presented here and the ones already described and included in the
phylogeny. Automatic Barcode Gap Discovery (ABGD) (Puillandre et al., 2012) was the
first method performed, implemented in the webpage: https://bioinfo.mnhn.fr/abi/public/
abgd/abgdweb.html. The default parameters were used, selecting initial partitions as
they are supposed to be more stable and generally give as a result a closer number of groups
described by taxonomists than recursive partitions. The second method applied was
the multi-rate Poisson Tree Process (mPTP) analysis (Kapli et al., 2017). The newick
tree obtained in the ML phylogenetic inference was used as input in the website
http://mptp.h-its.org/#/tree.
Anatomical methods
Specimens PT657-1 and 2 were sent to HDJ and are deposited in the Natural History
Museum, London, accession numbers NHMUK.2014.5.13.12-13. The larger specimen had
a visible gonopore, was assumed to be mature and selected for partial sectioning. It was
divided into four portions: anterior portion about 2 cm long not sectioned, in alcohol;
pre-pharyngeal section, TS, five slides, two at 15 µm, three at 10 µm; posterior portion
including pharynx and copulatory apparatus, LS, 16 slides (pharynx separated, HLS) at
15 µm. Sectioned portions were dehydrated in ethanol and embedded in paraffin wax.
Slides were stained in Harris’s haematoxylin and eosin and mounted in Canada balsam.
The second specimen, about 3.4 cm long, had no visible gonopore and remains in alcohol.
Colours are expressed as RAL colours (www.ralcolor.com).
The electronic version of this article in Portable Document Format (PDF) will represent
a published work according to the International Commission on Zoological Nomenclature
Mateos et al. (2020), PeerJ, DOI 10.7717/peerj.10013 3/15

Table 1 List of samples used in the molecular analysis with GenBank accession numbers.
Species/morphotype Locality GenBank Code
Cox1
Family Geoplanidae
Subfamily Rhynchodeminae
Tribe Caenoplanini
Artioposthia sp. Australia MN990642
Arthurdendyus testaceus –MN990643
Caenoplana coerulea New Zealand DQ665961
Menorca (Spain) JQ514564
Liverpool, UK DQ666030
El Prat de Llobregat (Barcelona, Spain) KJ659617
Vall de’n Bas (Girona, Spain) KJ659618
KJ659619
KJ659620
KJ659622
KJ659623
KJ659624
KJ659626
Badalona (Barcelona, Spain) KJ659633
KJ659634
Adelaide (Australia) KJ659642
–KJ659645
Granollers (Barcelona, Spain) KJ659647
PT1304 Real Jardín Botánico de Córdoba (Córdoba, Spain) MT727076*
PT1305 MT727077*
PT1307 MT727078*
PT1310 MT727079*
Caenoplana sp. 1 –DQ666031
Caenoplana sp. 2 Tallaganda (Australia) DQ227621
DQ227625
DQ227627
DQ227634
Caenoplana sp. 3 Victoria (Australia) DQ465372
Caenoplana sp. 4 –DQ666032
Caenoplana variegata Bordils (Girona, Spain) KJ659648
Southampton, UK MN990646
Cardiff, UK MN990647
MN990648
Caenoplana decolorata sp. nov. Bordils (Girona, Spain) KJ659628
KJ659629
KJ659630
KJ659631
KJ659632
Mateos et al. (2020), PeerJ, DOI 10.7717/peerj.10013 4/15

(ICZN), and hence the new names contained in the electronic version are effectively
published under that Code from the electronic edition alone. This published work and the
nomenclatural acts it contains have been registered in ZooBank, the online registration
system for the ICZN. The ZooBank Life Science Identifiers (LSIDs) can be resolved
and the associated information viewed through any standard web browser by
appending the LSID to the prefixhttp://zoobank.org/. The LSID for this publication is:
urn:lsid:zoobank.org:pub:B2636DF8-4372-405C-8A8C-4FBEC7396276. The LSID for
the new species described is: Caenoplana decolorata sp. nov. urn:lsid:zoobank.org:act:
C0CEE92F-A51E-4EDD-B18B-E7F021338667. The online version of this work is archived
and available from the following digital repositories: PeerJ, PubMed Central and
CLOCKSS.
RESULTS
Molecular results
The final dataset comprises 43 Cox1 sequences (including three outgroups, Table 1), with a
final length of 822 bp. The resulting ML tree (Fig. 2) shows monophyletic groups
comprising seven putative Caenoplana species. Although the bootstrap values (bb) are not
high enough to give support to the relationships between these clades, the monophyly
of the new species described here, C. decolorata, harbor maximum support. The results of
the molecular species delimitation analyses (both mPTP and ABGD) match the same
clades present in the phylogeny (Fig. 2) giving rise to seven putative Caenoplana species.
Among them, we find the subject of this study, Caenoplana decolorata.
Taxonomic section
Order Tricladida Lang, 1884
Suborder Continenticola Carranza et al., 1998
Family Geoplanidae Stimpson, 1857
Subfamily Rhynchodeminae von Graff, 1896
Tribe Caenoplaninae Ogren & Kawakatsu, 1991
Genus Caenoplana Moseley, 1877
Table 1 (continued)
Species/morphotype Locality GenBank Code
Cox1
MN990644
KJ659649
OUTGROUP: tribe Rhynchodemini
Dolichoplana sp.–DQ666037
D. striata Igreginha (Brazil) KC608226
Rhynchodemus sylvaticus Canyamars (Barcelona, Spain) FJ969946
Note:
*
Sequences obtained in this study.
Mateos et al. (2020), PeerJ, DOI 10.7717/peerj.10013 5/15

Caenoplana decolorata new species.
Caenoplana Ca2 Álvarez-Presas et al., 2014.
Etymology: “decolorata”indicating that live specimens resemble C. coerulea but are
comparatively pale and discolored.
NHMUK.2014.5.13.12-13
E. Mateos collection code PT657-1 and PT657-2. Locality: Bordils (Girona, Spain),
position N42.0348049 E2.8986153, date 22 October 2012.
Preserved dimensions: holotype (PT657-1): length 46 mm; width 2 mm; height 1 mm;
anterior to mouth 28 mm (61% of body length); anterior to gonopore 39 mm (85% of body
Figure 2 Maximum Likelihood (ML) phylogeny inferred with Cox1 sequences. Values at nodes
correspond to ultrafast bootstrap replicates (bb) obtained with IQtree software. Vertical bars to the right
of the phylogeny correspond to the molecular species delimitation methods results (mPTP, left bar and
ABGD, right bar). Scale bar represents number of substitutions per site. Photograph of specimen PT426
in dorsal view (anterior to the right). Full-size
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length); paratype (PT657-2): length 34 mm; width 2.1 mm; anterior to mouth 17 mm
(50%); apparently immature.
All other specimens (with a small section of the anterior end removed) are deposited in
the collection of M. Riutort at the University of Barcelona.
External characters
Live specimens are ‘mahogany brown’(RAL 8106) with a narrow ‘cream’(RAL 9001)
mid-line dorsally, merging to ‘beige brown’(RAL 8024) laterally. The anterior end is
‘copper brown’(RAL 8004). The ventral mid-line is ‘pastel turquoise’(RAL 6034) merging
into the lateral ‘beige brown.’
Eyes in a sparse uniserial row round the anterior end, biserial for a short distance behind
the anterior end and sparse staggered uniserial to the posterior end. Sole nearly the whole
of the ventral surface.
Anatomy
Transverse sections (Fig. 3A) are about 1.3 mm high and 2 mm wide. The ciliated creeping
sole is about 80% of the width. The cilia are about 5 µm long. The ventral epidermis is a
monolayer about 30 µm thick and has few rhabdites. Ventral sub-epidermal muscle
consists of a layer of circular muscle fibres about 10 µm thick and longitudinal muscle
in bundles about 30 µm thick. Dorsal to the longitudinal muscle bundles is a ventral
nerve plexus. There is a distinct, compact layer of parenchymal longitudinal muscle
ventrally, 40–50 µm thick, 150 µm in from ventral surface. Ventral nerve cords are about
750 µm centre to centre, about 120 µm in diameter, with transverse commissures. Laterally
and dorsally the parenchymal longitudinal muscle is less compact and 10–20 µm thick.
Dorsal epidermis is 45 µm thick, non-ciliated and has numerous rhabdites. Dorsal and
lateral sub-epidermal circular muscle is about 10 µm thick, and longitudinal muscle in
bundles about 35 µm thick. Rhabdites are numerous dorsally and laterally ental to the
sub-epidermal muscle, but in the mid-dorsal region, the rhabdites layer is slightly deeper
(Figs. 3A and 3B), presumed to be coincident with the pale midline visible in the living
animal.
The retracted cylindrical pharynx occupies the whole length of the pharyngeal pouch
and is about 2.5 mm long, 0.9 mm in diameter. The pouch is 5.4% of body length.
The pharyngeal aperture is about half way along the pharyngeal pouch. Pharyngeal
musculature consists of an outer layer of circular muscle about 10 µm thick, a layer of
mixed longitudinal and radial muscle about 360 µm thick and an inner layer of circular
muscle about 30 µm thick.
The anterior portion containing the ovaries has not been sectioned. Ovovitelline ducts
are about 500 µm apart on the inner dorsal surface of the ventral nerve cords (Figs. 3A
and 3D). Vitellaria are not distinguishable with certainty. Their outer and inner diameters
are about 25 µm and 7 µm respectively. They run to about 800 µm behind the gonopore,
turn dorsally and open into the common female duct about 800 µm long which
extends forwards with little differentiation to open into the common antrum above the
Mateos et al. (2020), PeerJ, DOI 10.7717/peerj.10013 7/15

gonopore (Figs. 4A,4C and 4E). There is little or no shell gland tissue surrounding the
common female duct.
Testes are numerous, ventral, ovate, about 200 µm wide and 300 µm high (Figs. 4A,
4D and 4E) and run almost to the copulatory apparatus. The sperm ducts cannot be
distinguished with certainty in transverse sections. They enter the anterior end of the
muscular bulb of the eversible penis, widen slightly and contain small amounts of stored
Figure 3 Caenoplana decolorata specimen PT657-1 (NHMUK2014.5.13.12). (A) Entire transverse
section (indicate the width of the ventral creeping sole; scale line 1 mm). (B) Enlarged mid-dorsal (scale
line 100 µm). (C) Enlarged mid-ventral (scale line 100 µm). (D) The testis, ventral nerve cord and
ovovitelline duct on one side (scale line 200 µm). (E) Longitudinal section showing several testes (scale
line 250 µm). Full-size
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sperm (Fig. 4B). They separately enter the anterior end of the ejaculatory duct which is
complex, long and sinuous, about 1.5 mm from its anterior end to the gonopore (Figs. 4A,
4B,4D and 4F). It has several regions, for ease of reference they are here arbitrarily
numbered 1–7 from anterior to posterior as follows. (1) A small chamber (seminal vesicle)
which extends transversely through 10 × 15 µm sections, thus about 150 µm wide, the two
Figure 4 Caenoplana decolorata specimen PT657-1 (NHMUK2014.5.13.12). (A) Reconstruction
diagram and (D–G) longitudinal sections of the copulatory apparatus (anterior to the left); (A), (B)
and (C) are to the same scale. Micrographs: (B and C) Mid-sections through the male and female portions
respectively (both folded sections) (scale lines 1,000 µm). (D and F) Further sections through the
proximal portion of the male ducts (scale lines 500 µm). (E) Section showing the approach of an
ovovitelline duct to the common female duct (scale line 500 µm). (G) Enlargement of region 4 of the male
duct (scale line 200 µm). The nuclei (cyanophil) are mostly adjacent to the lumen.
Full-size
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sperm ducts entering on either lateral extremity. (2) A narrow duct extending posteriorly
and turning ventrally and opening into, (3) a sinus-like duct wide laterally, 23 × 15 µm
thus 345 µm wide, but only 35 µm in the antero-posterior direction. This duct initially
turns ventrally then narrows and curves posteriorly to be almost U-shaped (second
arm shorter). The ejaculatory duct continues into, (4) a narrow sinus-like lumen
surrounded by strongly eosinophilic cells forming a structure roughly spherical in outline
about 400 µm in diameter. The cells of this region appear to be elongate with nuclei mostly
adjacent to the lumen (Fig. 4G). This in turn opens into, (5) a portion about 400 µm
long with sinuous margins, which in turn opens via, (6) a small papilla-like opening
into, (7) a longer and wider duct about 600 µm long with sinuous walls which can be
considered to be the male antrum. This in turn opens to the common antrum above the
gonopore.
DISCUSSION
The previous molecular results (Álvarez-Presas et al., 2014) analyzing only Caenoplana
sequences (and an outgroup) indicated that C. decolorata specimens are closely related to
Caenoplana variegata (Fletcher & Hamilton, 1888) (named as C. bicolor (von Graff, 1899)
in that work, see Jones et al., 2020) although without support. In the present work, the
tree shows a closer relationship between C. decolorata and C. coerulea, while C. variegata is
sister to the clade formed by these two species (plus some putative unknown species),
which will be an expected result having into account the more similar external
coloration pattern of the first two species. However, the bb values do not support the
relationships among species in the present work neither and make impossible to validate
this hypothesis.
The sectioned specimen has multiple eyes, ventral testes, a layer of parenchymal
longitudinal muscle, stronger ventrally, a long and fairly elaborate copulatory apparatus,
the ejaculatory duct particularly so, and other anatomical characters of the genus
Caenoplana Moseley, 1877 as amended by Ogren & Kawakatsu (1991) and by Winsor
(1991). Thus we are confident of the generic placement.
However, comparison with other Caenoplana species is problematic. Ogren &
Kawakatsu (1991) list 11 species of Caenoplana each with an anatomical description.
Winsor (1991) lists 19 species, seven ‘provisionally placed,’within Caenoplana. None of
those has a similar external coloration to the present specimens, and the ejaculatory
duct of the present specimens is distinctly different to that of any of those 11. They also
differ from C. variegata (Fletcher & Hamilton, 1888) (synonymous with C. bicolor
(von Graff, 1899), see Jones et al. (2020)).
Winsor (1997) lists a further six numbered, unnamed, Caenoplana species in addition to
two named species, C. coerulea coerulea (Moseley, 1877) and C. bicolor (von Graff, 1899).
Winsor (1998) states that 22 Caenoplana species were present in Australia, with no
other details. Presumably this total includes the six numbered, unnamed, species above.
Álvarez-Presas et al. (2014) list two further unnamed Caenoplana species, one the subject
of this paper. Whether either of these is similar to any of Winsor’s (1997) unnamed
species is unknown.
Mateos et al. (2020), PeerJ, DOI 10.7717/peerj.10013 10/15

In comparing this species to other Caenoplana species or to species placed in the
collective genus Australopacifica, particular attention should be made to those with a
broadly similar pigment distribution, that is those with, dorsally, a narrow mid-dorsal pale
line on an otherwise uniform dark colour (any dark colour) and ventrally with a more or
less uniform, but different, colour. The only two species with such a distribution are
C. coerulea Moseley, 1877 and C. purpurea (Dendy, 1895).
Caenoplana coerulea Moseley, 1877, originally found in New South Wales, Australia,
was described as follows: ‘entire body of a dark Prussian blue colour, somewhat lighter
on the under surface …with a narrow, mesial, dorsal, longitudinal stripe of white;’5cm
long. Hyman (1943,1954) and Ogren (1989) have described the anatomy of similar
specimens found in the USA. This species has distinctly different coloration from the
present specimens and the ejaculatory duct has a different structure (Ogren, 1989). It has
subsequently been found in New Zealand (Dendy, 1895), several European countries
(Álvarez-Presas et al., 2014) and North and South America (Ogren, 1989;Luis-Negrete,
Brusa & Winsor, 2011).
Geoplana purpurea Dendy, 1895, originally from South Island, New Zealand, was
described as follows: ‘dorsal surface rather dark reddish-purple …a very narrow median
band of nearly white,’‘ventral surface paler purple, under a lens appearing very finely
mottled in two shades;’3.5 cm long. Dendy (1895) comments: ‘it is perhaps doubtful
whether this species ought to be separated from the Australian G. coerulea, from which
it differs only in colour.’But in the same paper Dendy also records C. coerulea.
Geoplana purpurea was placed by Ogren & Kawakatsu (1991) in the collective genus
Australopacifica, with the note that ‘this probably belongs to Caenoplana on basis of
external similarities to Caenoplana coerulea.’Winsor (1991) ‘provisionally placed’it within
Caenoplana. There has been no anatomical description of specimens under that species
name. However, the coloration is different to the specimens from Spain and it seems
unlikely that the latter are of the same species.
None of the other species listed by Ogren & Kawakatsu (1991) under Australopacifica
has a colouration similar to the present species.
Thus the specimens do not match the description of any species previously described
and are described as a new species, Caenoplana decolorata.
One possible confusing factor is that the colour of some species has been shown to
vary over time and between individuals due to feeding (Jones et al., 2020;McDonald &
Jones, 2007). Only prolonged observations on live animals before and after feeding could
clarify if that might be the case with this species. Such observations would also indicate its
preferred prey.
The ejaculatory duct of the new species is distinctive. The structure here numbered 4 is
unlike anything present in any other described species of Caenoplana or for that matter
any other terrestrial planarian. The function of this structure is not obvious; it does not
appear to be either glandular or muscular.
Since at least one of the specimens was mature, it is presumed that this species reproduces
by sexual reproduction, though it is entirely possible that it may also reproduce by partial
fission, as in C. variegata (see Jones et al., 2020) and several other land planarian species.
Mateos et al. (2020), PeerJ, DOI 10.7717/peerj.10013 11/15

This species almost certainly originates from Australia since most Caenoplana species
are from there. It is presumed that it has been inadvertently transported to Spain in the
course of the trade in horticultural products.
FIGURE ABBREVIATIONS
1–7Arbitrary regions of the ejaculatory duct (see text)
cd Common female duct
gp Gonopore
clm Cutaneous longitudinal muscle
ml Median dorsal line
nc Nerve cord
od Ovovitelline duct
od–cd Opening of ovovitelline ducts to common female duct
plm Parenchymal muscle
rh Rhabdites
sd Sperm duct
tTestis
ACKNOWLEDGEMENTS
We thank Mónica López, from the Real Jardín Botánico de Córdoba (Spain), for
collecting and supplying some flatworm specimens from Córdoba. HDJ would like to
thank The School of Biological Sciences, University of Manchester and Peter Walker of the
histology laboratory, for access to facilities.
ADDITIONAL INFORMATION AND DECLARATIONS
Funding
This research was supported by the Ministerio de Ciencia, Innovación y Universidades,
Spain (project 2018-PGC2018-093924-B-100). The funders had no role in study design,
data collection and analysis, decision to publish, or preparation of the manuscript.
Grant Disclosures
The following grant information was disclosed by the authors:
Ministerio de Ciencia, Innovación y Universidades, Spain: 2018-PGC2018-093924-B-100.
Competing Interests
Marta Riutort is an Academic Editor for PeerJ.
Author Contributions
Eduardo Mateos conceived and designed the experiments, performed the experiments,
analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the
paper, and approved the final draft.
Mateos et al. (2020), PeerJ, DOI 10.7717/peerj.10013 12/15

Hugh D. Jones conceived and designed the experiments, performed the experiments,
analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the
paper, and approved the final draft.
Marta Riutort conceived and designed the experiments, performed the experiments,
analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the
paper, and approved the final draft.
Marta Álvarez-Presas conceived and designed the experiments, performed the
experiments, analyzed the data, prepared figures and/or tables, authored or reviewed
drafts of the paper, and approved the final draft.
Data Availability
The following information was supplied regarding data availability:
Cox1 data is available at GenBank: MN990642,MN990643,DQ665961,JQ514564,
DQ666030,KJ659617,KJ659618,KJ659619,KJ659620,KJ659622,KJ659623,KJ659624,
KJ659626,KJ659633,KJ659634,KJ659642,KJ659645,KJ659647,DQ666031,DQ227621,
DQ227625,DQ227627,DQ227634,DQ465372,DQ666032,KJ659648,MN990646,
MN990647,MN990648,KJ659628,KJ659629,KJ659630,KJ659631,KJ659632,
MN990644,KJ659649,DQ666037,KC608226,FJ969946.
New Species Registration
The following information was supplied regarding the registration of a newly described
species:
Publication LSID: urn:lsid:zoobank.org:pub:B2636DF8-4372-405C-8A8C-4FBEC7396276.
Caenoplana decolorata sp. nov.: urn:lsid:zoobank.org:act:C0CEE92F-A51E-4EDD-
B18B-E7F021338667.
Supplemental Information
Supplemental information for this article can be found online at http://dx.doi.org/10.7717/
peerj.10013#supplemental-information.
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