European Journal of Taxonomy 117: 1-11
http://dx.doi.org/10.5852/ejt.2015.117
BY
This work is licensed under a Creative Commons Attribution 3.0 License.
ISSN 2118-9773
www. europeanj ournaloftaxonomy. eu
2015 • Bostrom S. & Holovachov O.
Research article
urn:lsid:zoobank.org:pub:266D4101 -D1C7-4150-8EAD-B87EAE05E694
Description of a new species of Paracrobeles Heyns, 1968 (Nematoda,
Rhabditida, Cephalobidae) from Kelso Dunes, Mojave National
Preserve, California, USA
Sven BOSTROM 1 & Oleksandr HOLOVACHOV 2
1 -Department of Zoology, Swedish Museum of Natural History, Box 50007,
SE-104 05 Stockholm, Sweden.
1 E-mail: [email protected] (corresponding author)
2 E-mail: [email protected]
1 um:lsid:zoobank.org:author:528300CC-D0F0-4097-9631-6C5F75922799
2 urn:lsid:zoobank.org:author:89D30ED8-CFD2-42EF-B962-30A13F97D203
Abstract. A new species of Paracrobeles , P. kelsodunensis sp. nov. is described from the Kelso Dunes
area, Mojave National Preserve, southern California. Paracrobeles kelsodunensis sp. nov. is particularly
characterised by a body length of 469-626 pm in females and 463-569 pm in males; lateral field with
four incisures, extending almost to tail terminus; three pairs of asymmetrical lips, separated by U-shaped
primary axils with two long guarding processes, each lip usually with four tines along its margin; three
long labial probolae, deeply bifurcated, with slender prongs without tines; metastegostom with a strong
anteriorly directed dorsal tooth; pharyngeal corpus anteriorly spindle-shaped, posteriorly elongate
bulbous with dilated lumen; spermatheca 24-87 pm long; postvulval uterine sac 60-133 pm long;
vulva in a sunken area; spicules 33-38 pm long; and male tail with a 5-8 pm long mucro. The generic
diagnosis is emended on the basis of recently described species and a key to the species of Paracrobeles
is provided.
Keywords. Morphology, new species, Paracrobeles , SEM, taxonomy.
Bostrom S. & Holovachov O. 2015. Description of a new species of Paracrobeles Heyns, 1968 (Nematoda,
Rhabditida, Cephalobidae) from Kelso Dunes, Mojave National Preserve, California, USA. European Journal of
Taxonomy 117: 1-11. http://dx.doi.org/10.5852/eit.2015.117
Introduction
The genus Paracrobeles was erected by Heyns (1968), with Paracrobeles laterellus Heyns, 1968 as type
species, for a cephalobid from South Africa having: pharyngeal metacorpus developed into an elongate
median bulb with a large chamber; labial probolae long, bifurcate, sharply pointed, prongs without
fringe; and cephalic probolae prominent, sharply pointed without fringe. P. laterellus has also been
reported from Namibia by Rashid et al. (1990). Since then three new species have been described, viz.
P. psammophilus Navarro & Lluch, 1999 from Spain, P. mojavicus Taylor, Baldwin & Mundo-Ocampo,
2004 from California, USA and P. deserticola Abolafia, Divsalar, Panahi & Shokoohi, 2014 from Iran.
P. psammophilus was also recorded from Italy by Orselli & Vinciguerra (2002), who presented SEM
1
European Journal of Taxonomy 117: 1-11 (2015)
pictures of the species. A population of Paracrobeles from Kelso Dunes, Mojave National Preserve,
southern California, is described here from studies by light and scanning electron microscope. It is
close to P. mojavicus , but differs in some characters and is thus considered to represent a new species.
The generic diagnosis is emended on the basis of recently described species and a key to the species of
Paracrobeles is provided.
Materials and methods
During a tour in the Kelso Dunes area, Mojave National Preserve, southern California, the junior author
collected several samples of sand in the rhizosphere of different species of desert plants along the southern
slope of the dunes. Nematodes were recovered from sand samples using a modified Baermann funnel
extraction technique. For LM, specimens were relaxed by gentle heat, fixed in cold 4% formaldehyde
solution, transferred to pure glycerine by a slow evaporation method and mounted on permanent slides
in glycerine with paraffin wax as support for the coverslip. For SEM, specimens were post-fixed in
1% osmium tetroxide (0s0 4 ) and transferred to pure acetone through an acetone/distilled water series.
Specimens were critical point dried in liquid CCf, mounted on stubs, gold-plated under vacuum to a
thickness of 200 A in an Agar High Resolution Sputter Coater Model 20, and examined in a Hitachi
S-4300 SEM at an accelerating voltage of 5 kV.
Morphometric characters applied herein and their abbreviations are as defined for Cephalobidae in
De Ley et al. (1999); terminology of the labial and cephalic region and stoma follows that of Holovachov
et al. (2009). Type specimens are deposited in the invertebrate collections of the Department of Zoology,
Swedish Museum of Natural History, Stockholm, Sweden (SMNH).
Results
Phylum Nematoda Diesing, 1861
Class Chromadorea Inglis, 1983
Order Rhabditida Chitwood, 1933
Family Cephalobidae Filipjev, 1934
Genus Paracrobeles Heyns, 1968
Type species
Paracrobeles laterellus Heyns, 1968
Diagnosis (emended after Holovachov et al. 2009)
Cuticle annulated, without distinctly annulated internal layer; annuli with longitudinal striation (tessellated).
Lateral field with two wings (three or four incisures), ending near tail terminus in females and in males.
Lip region weakly offset, consisting of six lips arranged in three pairs: one dorsal and two subventral. Pairs
of lips separated by primary axils with one or two acute triangular guarding processes; secondary axils
shallow. Cephalic probolae with three or four long and slender tines. Labial probolae deeply bifurcated
without tines along the slender prongs. Six outer labial and four cephalic papilliform sensilla arranged in
a cephaloboid manner. Amphidial aperture rounded, located on lateral lips. Stoma divided into cheilo-,
gymno- and stegostom: cheilostom barrel-shaped, with strongly sclerotized bacilliform cheilorhabdia;
gymnostom narrow tubular, as wide as stegostom, with weakly sclerotized plate-like gymnorhabdia;
stegostom consists of a funnel-shaped prostegostom and variably shaped mesostego-, metastego- and
telostegostom parts. Metastegostom tooth absent or present. Pharynx cephaloboid: pharyngeal procorpus
cylindrical; metacorpus elongate bulbous; lumen of metacorpus often expanded to a large triradiate
chamber with seemingly sclerotized lining; isthmus narrower than metacorpus; basal pharyngeal bulb
oval, with strongly developed valves. Nerve ring encircling metacorpus, metacorpus-isthmus junction or
2
BOSTROM S. & HOLOVACHOV O., New species of Paracrobeles from Kelso Dunes
anterior part of isthmus. Excretory pore opens at level of nerve ring. Deirids present. Female reproductive
system cephaloboid; posterior part of ovary straight and relatively short; spermatheca present; postvulval
uterine sac present; vulva flat with contour of body or in a depression; vagina straight or directed
anteriad. Male reproductive system cephaloboid; spicules cephaloboid, with corpus and manubrium of
approximately equal width; gubernaculum plate-lilce; cornua crurum absent. Male genital papillae: two
ventrosublateral pairs located anterior to cloaca; one ventrosublateral pair located just posterior to cloacal
opening; two pairs located at middle of tail length; and three pairs (lateral, subventral and subdorsal) near
tail terminus; there is a midventral papilla on anterior cloacal lip. Rectum short (about as long as anal
body diameter). Phasmid openings located at about one-third to half of tail length in both sexes. Female
tail conoid, straight or slightly arcuate ventrad, tail terminus pointed or finely rounded; male tail conoid,
slightly arcuate ventrad, tail terminus finely rounded.
Valid species
P. deserticola Abolafia, Divsalar, Panahi & Shokoohi, 2014
P. laterellus Heyns, 1968
P. mojavicus Taylor, Baldwin & Mundo-Ocampo, 2004
P. psammophilus Navarro & Fluch, 1999
Paracrobeles kelsodunensis sp. nov.
urn:lsid:zoobank.org:act:3D3142CA-44FA-422F-9B6A-8A988B3B75EC
Figs 1-2, 3A-C, I; Table 1
Diagnosis
Paracrobeles kelsodunensis sp. nov. is characterised by a body length of 469-626 pm in females and
463-569 pm in males; cuticle coarsely annulated, annuli 3.0—4.8 pm wide at midbody; lateral field
with two wings, each separated by a broad groove, extending almost to tail terminus; three pairs of
asymmetrical lips, pairs of lips separated by U-shaped primary axils, with two long guarding processes
emerging from the first annule, each lip with four (usually) or three (rarely) tines along its margin: two
long acute, with or without one shorter in the middle, and one long acute extending along the secondary
axil; three long labial probolae, deeply bifurcated, with slender prongs without tines; metastegostom with
a strong, anteriorly directed dorsal tooth; pharynx corpus anteriorly spindle-shaped, posteriorly elongate
bulbous with dilated lumen; isthmus narrow, demarcated by a break in muscular tissue: anteriorly with
heavy musculature, posteriorly further narrowing with reduced musculature; pharyngeal corpus 2.5-
3.3 times isthmus length; nerve ring and excretory pore at level of metacorpus to metacorpus-isthmus
junction; spermatheca 24-87 pm long; postvulval uterine sac 60-133 pm long; vulva in a depression;
spicules 33-38 pm long; and male tail with a 5-8 pm long mucro.
Etymology
The new species name refers to the place where it was found.
Material examined
USA: holotype §, paratypes 15 $ $ and 9 $$, SMNH Type-8715-Type 8720, 28 Mar. 2010, California,
Mojave National Preserve, Kelso Dunes, soil around roots of desert plants (34°53.698’ N, 115°42.155’ W;
34°53.754’ N, 115°42.248 9 W and 34°54.226’ N, 115°42.200’ W), legit O. Holovachov & P. De Fey.
Description
Adult
Body variably arcuate when killed by heat. Cuticle coarsely annulated, annuli 3.0—4.8 pm wide at
midbody. Irregular longitudinal striae give the cuticle a tiled appearance. Fateral field with two wings.
3
European Journal of Taxonomy 117 : 1-11 ( 2015 )
areolated, each separated by a broad groove, appearing as four incisures under LM, occupying about
20% of body diameter, extending almost to tail terminus in both sexes. Lip region weakly offset, carrying
6 + 4 papillae and two rounded amphid apertures. Three pairs of asymmetrical lips, one dorsal and
two ventrolateral. Pairs of lips separated by U-shaped primary axils, with two long guarding processes
emerging from the first annule. Each lip with four (commonly) or three (rarely - seen in one specimen
so far) tines along its margin: two long acute, with or without one shorter in the middle, and one long
acute extending along the secondary axil. Three labial probolae, 13.0-15.5 pm long, deeply bifurcated,
with slender prongs without tines. Stoma about one lip region diameter long. Stomatal parts not clearly
discernible. Cheilorhabdia oval in latero-median view; metastegostom with a strong, anteriorly directed
dorsal tooth. Pharyngeal corpus anteriorly spindle-shaped, posteriorly elongate bulbous with dilated
lumen; isthmus narrow, demarcated by a break in muscular tissue: anteriorly with heavy musculature,
posteriorly further narrowing with reduced musculature; bulb oval, with valves. Nerve ring and excretory
pore vary in position, from the level of metacorpus to metacorpus-isthmus junction, at 60-68% of neck
length and at 57-68% of neck length, respectively. Deirids at level of isthmus, at 69-82% of neck length.
Excretory canal cuticularised distally.
Female
Reproductive system monodelphic, prodelphic, in dextral position in relation to intestine. Ovary reflexed
posteriorly at oviduct, ovary straight posterior to vulva. Spermatheca well developed. Postvulval uterine
sac large, 1.4-3.1 times vulval body diameter (VBD) long. Vagina straight and perpendicular to body
axis, about one-third to two-fifths of VBD. Vulva in a sunken area. Intra-uterine eggs 43-66 x 30-36 pm.
Tail conoid, generally slightly curved ventrad, curved dorsad in some specimens, with 16-21 ventral
annuli, non-annulated in terminal 6-12 pm, terminus minutely rounded. Rectum sigmoid, about half of
ABD long. Phasmid openings located at about one-third to two-fifths of tail length.
Male
Similar to female in most respects, except for the sexual characters. Reproductive system monorchic,
dextral in position; testis reflexed ventrad anteriorly. Spicules slender, paired and symmetrical, strongly
curved ventrad; with oval manubrium and subcylindrical, gradually narrowing shaft. Gubernaculum
plate-like. Genital papillae distributed as follows: two pairs ventrosublateral precloacal (at 5-11 pm
and at 45-57 pm anterior to cloaca), one pair ventrosublateral adcloacal, a single midventral on anterior
cloacal lip; two pairs (one ventrosublateral and one lateral) at midtail; three pairs (one lateral, one
subventral and one dorsosublateral) near tail terminus. Phasmid openings located at about two-fifths of
tail length, one to two annuli posterior to the lateral midtail papillae. Tail slightly curved ventrad, conoid,
with a 5-8 pm long mucro and minutely rounded terminus.
Remarks
The population of Paracrobeles kelsodunensis sp. nov. from Kelso Dunes described here agrees in many
respects with the description of P. mojavicus collected from sandy soil in a lava field, Mojave Desert,
California. The new species differs from P. mojavicus by having a prominent, anteriorly directed, dorsal
metastegostom tooth (vs no metastegostom tooth); a somewhat more anterior position of the excretory
pore (at level of metacorpus or metacorpus-isthmus junction vs at level of isthmus); male tail with a
5-8 pm long mucro (vs male tail without mucro). Type specimens of P. mojavicus were examined (see
Fig. 3D-I) and among them, one male (Fig. 31) was found to have a prominent metastegostom tooth. The
presence of a metastegostom tooth has not been described for any other species than P. kelsodunensis
sp. nov., which might indicate that the population described by Taylor et al. (2004) is a mixture of
species. One possible explanation could be a polymorphism based on food sources, and a comparison
between molecular characters would probably be needed to resolve the status of the Paracrobeles
populations from the Mojave Desert.
4
BOSTROM S. & HOLOVACHOV O., New species of Paracrobeles from Kelso Dunes
Fig. 1 . Paracrobeles kelsodunensis sp. nov. A. Pharyngeal region. B. Female gonad. C. Female tail.
D. Male tail. Scale bar = 20 pm.
European Journal of Taxonomy 117: 1-11 (2015)
Fig. 2. Paracrobeles kelsodunensis sp. nov. SEM micrographs. A. Anterior end, left lateral view.
B. Anterior end, semi-en face view. C-D. Anterior end, subventral view. E. Vulval region. F. Male tail,
ventral view. G. Female tail, right sublateral view (arrow points at phasmid). H. Male tail, left lateral
view (arrows point at papillae). I. Male tail, left lateral view (arrow points at phasmid). Scale bars:
A-D = 5 pm, E-I =10 pm.
6
BOSTROM S. & HOLOVACHOV O., New species of Paracrobeles from Kelso Dunes
Fig. 3. A-C. Paracrobeles kelsodunensis sp. nov. LM micrographs. A. Male anterior end, ventral side
to the right. B-C. Female anterior end, ventral side to the right. D-H. Paracrobeles mojavicus Taylor,
Baldwin & Mundo-Ocampo, 2004. D-F. Female anterior end, ventral side to the right. G-H. Male
anterior end, ventral side to the right. I. Paracrobeles cf. kelsodunensis sp. nov., male anterior end,
ventral side to the right. Scale bar: A-I =10 pm.
7
European Journal of Taxonomy 117: 1-11 (2015)
Table 1. Measurements (in pm) of Paracrobeles kelsodunensis sp. nov. from Kelso Dunes, Mojave
Desert, California (presented as mean±s.d. and (range) or only range). * Number of annuli from anterior
end to nerve ring, excretory pore and deirid, respectively; - indicates that data is not applicable.
Holotype $
16 $$ (incl. holotype)
9 3 $
Body length
626
538±51 (469-626)
514±33 (463-569)
Body diameter (BD)
42
43.0±3.2 (37N9)
37.5±2.3 (34N1)
Pharynx length
185
169±11.8 (150-188)
161.5±9.5 (147-173)
Tail length
66
54.5±6.4 (42-66)
54.0±3.9 (47-58)
Anal or cloacal diameter (ABD)
29
27.6±1.7 (25-31)
29.9±0.9 (28-31)
Vulva or Testis
391
334±29.1 (297-391)
265±31 (223-315)
V-A/T
2.8
2.8±0.3 (2.5-3 4)
—
a
14.9
12.5±1.0 (10.9-14.9)
13.7±1.2 (12.1-16.7)
b
3.4
3.2±0.2 (2.9-3.7)
3.2±0.2 (2.9-3.6)
c
9.5
10.0±0.6 (9.1-11.5)
9.6±1.0(8.0-11.8)
c’
2.3
2.0±0.2(1.6-2.3)
1.8±0.2(1.6-2.1)
V or T (%)
62.5
62.0±1.2 (60-65)
51.1±5.1 (44-59)
Lip region diameter
18
17.7±0.4 (17-18)
17.1±0.6 (16-18)
Labial probolae
15.5
14.7±0.7 (13.0-15.5)
14.1±0.6 (13.0-14.5)
Stoma length
14.5
14.9±0.5 (14.5-15.5)
15.1±0.5 (14.5-15.5)
Corpus length
114
106.1±5.3 (100-119)
99.7±3.9 (94-105)
Isthmus length
39
35.9±3.5 (30N2)
33.4±2.3 (29-37)
Bulb length
30
29.6±1.2 (28-33)
29.9±1.0(28-31)
Bulb diameter
22
22.3±1.0(20-23)
21.0±0.9 (20-22)
Corpus/isthmus ratio
2.9
3.0±0.3 (2.5-3.3)
3.0±0.2 (2.7-3.3)
Nerve ring from anterior end
133
123.9±7.7 (112-142)
119.0±8.0 (109-137)
Excretory pore from anterior end
141
119.4±10.4 (102-142)
114.8±10.8 (101-133)
Deirid from anterior end
161
152.8±11.1 (135-163)
134.0±13.4 (110-155)
n a
R,,„
NR
24
26.1±1.4 (23-29)
26.4±1.2 (24-28)
|> A
26
24.9±1.3 (22-27)
25.3±1.2 (24-27)
R *
^DFI
31
31.8±2.2 (29-36)
30.8±2.2 (27-34)
Annuli width at midbody
4.ON.8
3.ON. 8
3.4N.0
Annuli width anteriorly
4.ON.8
3.4-4.8
3.0N.0
Vagina or Testis flexure length
14.5
13.6±0.8 (13.0-15.5)
47.7±13.0 (31-72)
Spermatheca or Spicule length
60
49.7±16.8 (24-87)
35.1±1.5 (33-38)
PUS or Gubernaculum length
129
102.1±20.4 (60-133)
19.9±1.3 (18-22)
PUS/VBD
3.1
2.6±0.5(1.4-3.1)
—
Rectum
18
17.9±1.3 (14.5-20.5)
—
Rectum/ABD
0.6
0.6±0.1 (0.5-0.7)
—
Phasmid
20.5
19.1±1.9 (16-29)
21.5±2.5 (18-26)
Phasmid (% of tail)
31
35.5±3.4 (31N0)
40.1±2.8 (37N5)
Key to species of Paracrobeles (emended after Abolafia et al. 2014; when using the key, please also
consult Table 2 for additional diagnostic information)
1. Spicules less than 40 pm long.2
- Spicules more than 40 pm long, primary axils with single guarding process.4
2. Vulva at 58-60% of body length. P. laterellus Heyns, 1968
- Vulva at 60-71% of body length, primary axils with two guarding processes.3
3. Metastegostom tooth absent. P. mojavicus Taylor, Baldwin & Mundo-Ocampo, 2004
- Metastegostom tooth present, anteriorly directed. P. kelsodunensis sp. nov.
8
Table 2. Morphometries of Paracrobeles species. Measurements in pm (except L, in mm) (emended from Abolafia et al., 2014). * Measured from the
illustrations or calculated from other measurements; ** times the corresponding body diameter; - indicates that data are not applicable; Abolafia et al.
(2014); 2 Heyns (1968); 3 Rashid et al. (1990); 4 Taylor et al. (2004); 5 Navarro & Lluch (1999); 6 Orselli & Vinciguerra (2002); 7 Present paper.
BOSTROM S. & HOLOVACHOV O., New species of Paracrobeles from Kelso Dunes
Country
Iran
Namibia
Namibia
California,
USA
Spain
»
HH
California,
USA
Postvulval sac or
Gubernaculum
60-96
2.9M.5**
16-24
1.0-1.5**
17-22
46
54-110
17-22
57-101
20-39
65-106
28-31
60-133
1.4-3.1**
18-22
Spermatheca
or Spicules
33-50
46-56
32-35/43M6
26
38-77
28-37
48*
42-57
30-37
68-81
24-87
33-38
Tail
53-67
48-54
50-60
50-55
o
in
41-66
43-67
46-53
42-53
58-68
56-70
42-66
47-58
Excretory pore
-ant. end.
96-111
101-120
106*
107
115-163
103-160
69-117
75-107
114-139
102-142
101-133
Labial
probolae
14- 16
15- 16
*
o 1
*
OS
11-17
11-17
10-12
11-18
13-17
13-16
13-15
Stoma
length
11- 14
12- 14
a\ 1
Cl
13-18
13-18
10-14
10-14
10-18
12-19
14-16
14-16
(%) A
50-63
58-60
G\
in
62-71
59-63
59-62
60-65
2.0-3.0
1.8-2
2.3*
2.0*
2.2
1.8-2.5
1.7-2.3
1.9-2.7
1.6-2.2
2.2-2.8
1.7-2.8
1.6- 2.3
1.6- 2.1
u
9-10
9-13
11-15
11-12
-
9- 13
10- 12
7-11
9-12
8-10
8-9
9-12
8-12
3.0M.0
3.0M.0
3.3-4.1
3.5-3.9
3.7
2.6- 3.5
2.7- 3.7
2.9-3.7
3.1-3.6
2.3- 2.9
2.4- 3.2
2.9- 3.7
2.9- 3.6
CS
14-18
13-19
17-20
17-25
oo
13- 18
14- 19
10-17
10-18
13-16
12-20
11- 15
12- 17
-
0.48-0.60
0.46-0.65
0.53-0.74
0.57-0.66
0.57
0.47-0.71
0.45-0.75
0.36-0.55
0.42-0.53
0.49-0.58
0.52-0.61
0.47-0.63
0.46-0.57
=
Of
o+ ^o
oo oo
Of 'fo
Of 'A)
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Of
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r- On
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o o
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Cl
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£ o
Species
o
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(N
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Si
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CO
§
8!
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§
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s
ir>
§
•fx*
-s:
&
2
2
a
S
I*
s
s
a
kelsodunensis 1
sp. nov.
9
European Journal of Taxonomy 117: 1-11 (2015)
4. Lips with three tines (including the ones in secondary axils); postvulval sac not swollen.
. P. deserticola Abolafia, Divsalar, Panahi & Shokoohi, 2014
- Lips with four tines (including the ones in secondary axils); postvulval sac swollen.
. P. psammophilus Navarro & Liu eh, 1999
Discussion
The Mojave Desert and especially the Kelso Dunes seem to be an area with a high diversity of species
of the family Cephalobidae Filipjev, 1934. Representatives of this family are mostly terrestrial and
bacteria-consuming nematodes with a worldwide distribution. They seem to be especially diverse and
abundant in deserts, and sand dunes appear to be a suitable habitat for cephalobids. About ten new
species have been described from the Mojave Desert, which might indicate a hot spot for cephalobid
diversity (De Ley 2014). Hitherto one new genus and six new species, including the one described here,
and one already known species have been described from the Kelso Dunes (Bostrom & Holovachov
2012, 2013a, 2013b, 2014). Some of the new species described from the Mojave Desert are closely
related, which might further indicate that speciation processes are going on in this area. Species of the
genus Paracrobeles are rare inhabitants of terrestrial ecosystems and have a rather restricted distribution.
So far they have been found in warm, dry sandy soils in southern Africa (South Africa and Namibia),
the Mediterranean (Spain and Italy), California and Iran (Abolafia et al. 2014; Heyns 1968; Navarro &
Lluch 1999; Orselli & Vinciguerra 2002; Rashid et al. 1990; Taylor et al. 2004). The description of the
new species adds morphological data important for species identification and broadens the diagnosis of
Paracrobeles.
Acknowledgements
The second author was supported in part by an award from the NSF Partnerships for Enhancing
Expertise in Taxonomy (PEET) program grant “PEET: Training the Next Generation of Nematode
Taxonomists: Applying the Tools of Modern Monography Across Free-living and Parasitic Tylenchina”
(DEB-0731516). Sampling was performed by O. Holovachov and P. De Ley under permit # MOJA-
2010-SCI-0003 from the National Park Service, United States Department of Interior.
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Manuscript received: 9 December 2014
Manuscript accepted: 15 January 2015
Published on: 23 March 2015
Topic editor: Rudy Jocque
Desk editor: Charlotte Thionois
Printed versions of all papers are also deposited in the libraries of the institutes that are members of the
EJT consortium: Museum national d’Histoire naturelle, Paris, France; Botanic Garden Meise, Belgium;
Royal Museum for Central Africa, Tervuren, Belgium; Natural History Museum, London, United
Kingdom; Royal Belgian Institute of Natural Sciences, Brussels, Belgium; Natural History Museum of
Denmark, Copenhagen, De nm ark
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