New cave species of Cyphoderus Nicolet and Pararrhopalites Bonet & Tellez (Hexapoda, Collembola) from Caatinga biome, Brazil
Author
Souza, Paolla Gabryelle Cavalcante De
0000-0003-0612-8438
Graduate Program of Biological Science (Zoology). Centre of Exact Sciences and Nature (CCEN), Federal University of Paraíba (UFPB), João Pessoa, Paraíba, Brazil & Department of Botany and Zoology, Biosciences Center, Federal University of Rio Grande do Norte (UFRN), Brazil
paollasouzac@gmail.com
Author
Medeiros, Gleyce Da Silva
0000-0001-9839-2345
Department of Botany and Zoology, Biosciences Center, Federal University of Rio Grande do Norte (UFRN), Brazil
gleycemedeiros96@gmail.com
Author
Bento, Diego De Medeiros
Centro Nacional de Pesquisa e Conservação de Cavernas (CECAV), Base Avançada em Natal, 59015 - 350, Tirol, Natal, Rio Grande do Norte, Brazil (DMB)
Author
Zeppelini, Douglas
Graduate Program of Biological Science (Zoology). Centre of Exact Sciences and Nature (CCEN), Federal University of Paraíba (UFPB), João Pessoa, Paraíba, Brazil & Laboratory of Systematics of Collembola and Conservation, Institute of Soil Biology-State University of Paraiba, Brazil.
Author
Bellini, Bruno Cavalcante
0000-0001-7881-9436
Department of Botany and Zoology, Biosciences Center, Federal University of Rio Grande do Norte (UFRN), Brazil
entobellini@gmail.com
text
Zootaxa
2024
2024-06-27
5474
3
201
224
http://dx.doi.org/10.11646/zootaxa.5474.3.1
journal article
10.11646/zootaxa.5474.3.1
1175-5326
12567622
8195C49D-7E8A-4363-9F43-0268144AA946
Cyphoderus caatinguensis
sp. nov.
Souza, Bellini & Zeppelini
Figs 1
,
3–7
,
Table 1
Type material.
Holotype
male in slide:
Brazil
,
Rio Grande do Norte State
,
Felipe Guerra
,
Caverna Boa
(
05°33’59.5”S
;
37°41’52.4”W
),
Aphotic
zone,
21/VII/2022
,
Souza, P.G.C
,
Santos, N. M. C.
,
Lima, E. C. A.
,
Bento, D. M.
,
Freitas, J. I. M.
coll. (
CC
/
UFRN
)
.
Paratypes
:
1 female
in slide, same data of
holotype
(
CC
/
UFRN
)
;
5 females
and
1 juvenile
in slide, same data of
holotype
except
23/VII/2019
,
Souza, P.G.C
,
Bellini, B. C.
,
Santos, N. M. C.
,
Bento, D. M.
,
Freitas, J. I. M.
coll. (
CC
/
UFRN
); and
2 females
in slides, same data of
holotype
except
23/VII/2019
,
Souza, P.G.C
,
Bellini, B. C.
,
Santos, N. M. C.
,
Bento, D. M.
,
Freitas, J. I. M.
coll. (
CRFS
/
UEPB
)
.
Diagnosis.
Mandibles normal, not modified. Labial papilla
E
lateral process finger-shaped, surpassing the apex of the papilla. Labial basal chaetae formula as:
m
,
e
,
l1–2
,
a1–5
,
l2
reduced to a minute smooth chaeta,
r
chaeta absent. Dorsal head with five antennal macrochaetae (
f1–5
),
A0
macrochaeta present,
Pa5
as mesochaeta, other chaetae as microchaetae. Abd. IV with one internal and one external macrochaetae (
B4
and
E3
, respectively). Trochanteral organ with 16–19 spine-like smooth chaetae. Ungues with 4 inner teeth, basal pair asymmetrical (basal posterior tooth much larger than basal anterior one), unpaired apical tooth long and filamentous, tenent hairs capitate. Collophore posterior side with 3 ciliate chaetae (1 unpaired), 2 smooth small spines and 1–3 long, smooth distal chaetae. Dens dorsally with 8–10 inner and 8 outer feathered chaetae. Mucro short and with 4 teeth, belonging to
tridenticulati
group, with teeth formula as:
aAi
.
Description.
Body length (head + trunk) of specimens
1.2–2.16 mm
(n = 5),
holotype
1.87 mm
, male with
1.87 mm
, females with
1.2–2.16 mm
(n= 4). Habitus typical of the genus, specimens totally unpigmented. Scales covering Ant. I–II, ventral and dorsal head, dorsal trunk, lateral and ventral manubrium and dens. Legs and collophore without scales.
Antennae shorter than the body length. Antennae segments ratio I: II: III: IV of the
holotype
as 1: 2.36: 1.81: 3.91. Ant. IV without apical bulb, with ciliate chaetae and at least
three types
of sensilla (types ‘2’ and ‘3’, elongated sensillum; type ‘4’, finger-shaped sensillum; type ‘10’, minute sensillum with rounded apex,
sensu
Jantarit
et al.
2014
). Ant. III with 2 sensory rods (type ‘7’
sensu
Jantarit
et al.
2014
) and 2 guard sensilla (type ‘5’
sensu
Jantarit
et al.
2014
). Ant. II with dorsal scales and at least
4 types
of sensilla (types ‘2’, ‘3’, ‘4’ and ‘9’). Ant. I with dorsal scales, multiciliate chaetae and 3 smooth chaetae (
Fig. 3A
). Prelabral chaetae smooth, labral chaetotaxy with 4 (
a1–2
), 5 (
m0–2
,
m2
shorter than
m1
) and 5 (
p0–2
) smooth chaetae, labral papillae absent (
Fig. 3B
). Clypeal formula with 4 (
l1–2
), 2 (
ft
) and 3 (
pf0–1
) smooth chaetae,
pf0
slightly longer than
pf1
(
Fig. 3B
). Mandibles regular, without modifications, asymmetrical, with 5+4 teeth (
Fig. 3C
). Maxillae capitulum globular, without any clear modifications. Labial palp with 6 papillae, formula of the guards as:
H
(2),
A
(0),
B
(5),
C
(0),
D
(4),
E
(4) + a lateral process finger-shaped and surpassing the apex of papilla
E
(
Fig. 4D
). Outer lobe of maxilla with the basal chaeta longer than the apical one, both smooth, sublobal plate with one chaeta-like appendage, oral fold with 2 smooth chaetae (
Fig. 3E
). Labial basolateral and basomedian fields with chaetae
m
,
e
,
l1–2
and
a1–5
all smooth,
l2
reduced to a minute chaeta,
r
chaeta absent, 5 labial proximal chaetae (
lpc
), all smooth (
Fig. 3F
). Ventral postlabial formula of the anterior chaetae as: 4 (
G1–4
), 2 (
X
,
X4
), 4 (
H1–4
), and 2 (
J1–2
) chaetae, chaeta
X
strongly reduced and smooth, posterior region with 2–3 basal chaetae (
Fig. 3F
). Dorsal head chaetotaxy with 5 antennal macrochaetae (
f1–5
), 1 anterior macrochaeta (
A0
) and 4 microchaetae (
A1–3
,
A5
), 4 medial microchaetae (
M1–4
), 6 sutural microchaetae (
S0
,
S2–5
), 2 post-sutural microchaetae (
Ps2
,
Ps5
), 4 postero-anterior chaetae (
Pa2–3
as microchaetae,
Pa5
as mesochaeta,
Pa
as the post-ocular bothriotrichum), plus 1 microchaeta of uncertain homology, 2 postero-medial microchaetae (
Pm1–Pm3
), 6 post-occipital posterior microchaetae (
Pp1?
,
Pp3–7
) and 1 postero-external (
Pe3
) microchaeta (
Fig. 3G
).
Central macrochaetae formula from Th. II to Abd. IV as: 0,0|0,1,0,1, sensilla formula (Th. II–Abd. V) as: 1,1|0,1,1,+,3, microsensilla formula as: 1,0|1,0,1,0,0. Th. II without macrochaetae other than those in the anterior collar, with 3–4 anterior (
a2
,
a3?
,
a5
plus one microchaeta of uncertain homology), 6 medial (
m1–2
,
m4–m6e?
), 6–7 posterior (
p1–p6e
) microchaetae (
Fig. 4A
). Th. III with 3 anterior (
a2
,
a6–a7
), 4 medial (
m6–m6p
,
m7–m7e
) and 4 posterior (
p2–4
,
p6
) chaetae (
Fig. 4B
). Abd. I with 1
ms
and 5 medial (
m2–m6
) microchaetae (
Fig. 4C
). Abd. II with 5 anterior (
a2i
,
a2
,
a5–7
), 6 medial (
m2–3
,
m3e
,
m3ep
,
m6–7
) and 2 posterior (
p5
,
p7
) chaetae,
m2
and
a5
as bothriotricha,
a2i
,
a2,
and
m3e
as their accessory chaetae (
Fig. 4D
). Abd. III with 5 anterior (
a2i
,
a2
,
a5–7
), 9 medial (
m2–3
,
m3e
,
m3e2
,
m5
,
am6
,
pm6
,
m7i–m7
) and 3 posterior chaetae (
p6–7
plus one microchaeta without clear homology),
a5
,
m2
, and
m5
as bothriotricha,
a2
,
m3e
,
m3e2
and 2–4 extra ones as their accessory chaetae (
Fig. 4E
). Abd. IV with chaetae formula as: 4 ‘
A
’ (
A3–A6
), 4 ‘
B
’ (
B3–B6
,
B4
as macrochaetae), 4–5 ‘
C
’ (
C1–4
), 7 ‘T’ (
T1–7
), 3 ‘
D
’ (
D1–3
), 4 ‘
E
’ (
E1–4
,
E3
as macrochaetae), 3 ‘
F
’ (
F1–3
) and 3 ‘
Fe
’ (
Fe2–4
); 1 posterior (
ps
) and at least 2 internal sensilla, posterior region with 5 transversal mesochaetae and 3–4 pseudopores (
Fig. 5A
). Abd. V with 5 anterior (
a1
,
a3
,
a5–6e
), 3 medial (
m2–3
,
m5
) and 4 posterior (
p1
,
p3–5
) main mesochaetae (
Fig. 5B
).
Trochanteral organ with 16–19 smooth spine-like chaetae (
Figs 6A–B
), femur III with several smooth spine-like chaetae similar to those of the trochanteral organ (
Fig. 6B
). Tibiotarsi I–III with an internal row of finely ciliate, abruptly pointed macrochaetae (
Fig. 6C
). Ungues with 4 inner teeth, 2 paired basal asymmetrical (basal posterior tooth remarkably larger than basal anterior tooth), 1 unpaired median and 1 unpaired apical tooth longer than the median tooth and filamentous; ungual outer side with one pair of lateral teeth and 1 unpaired dorsal tooth (
Figs 6D–F
). Unguiculi wing-shaped, with 4 smooth lamellae, anterointernal lamella with a large tooth (
Fig. 6D
). Tenent hairs capitate, longer than the inner distal smooth chaeta on tibiotarsus III (
Fig. 6D
).
FIGURE 3.
Cyphoderus caatinguensis
sp. nov.
head:
A
, Dorsal view of the left antenna chaetotaxy;
B
, Clypeal, pre-labral and labral chaetotaxy;
C
, Mandibles;
D
, Labial palp papillae with proximal chaetae (
lpc
) (right side), lateral process (
l
.
p
.) surpassing the papilla E;
E
, Maxillary outer lobe and sublobal plate (left side);
F
, Basal labial and post-labial chaetotaxy with basal chaetae (
b
.
c
.);
G
, Dorsal head chaetotaxy.
FIGURE 4.
Cyphoderus caatinguensis
sp. nov.
dorsal trunk chaetotaxy, right side:
A
, Th. II;
B
, Th. III;
C
, Abd. I;
D
, Abd. II;
E
, Abd. III. Abbreviations:
ms
= microsensillum,
al
= anterolateral sensillum,
as
= anterosubmedial sensillum.
FIGURE 5.
Cyphoderus caatinguensis
sp. nov.
dorsal trunk chaetotaxy, right side (cont.):
A
, Abd. IV;
B
, Abd. V.
FIGURE 6.
Cyphoderus caatinguensis
sp. nov.
legs:
A
, Trochanteral organ spine-like chaetae;
B
, Trochanteral organ (white arrow) and femur III (black arrow) with smooth spine-like chaetae;
C
, Tibiotarsus III internal mac with abruptly pointed apex (black arrow);
D
, Foot complex III, anterior view;
E–F
, Ungues II (
E
) and III (
F
), respectively, black arrows mark the medial and apical teeth. Abbreviations:
b
.
a
. = basal anterior tooth,
b
.
p
. = basal posterior tooth,
m
.
t
. = unpaired median tooth,
a
.
t
. = unpaired apical tooth,
a
.
e
. = anteroexternal lamella;
a
.
i
. = anterointernal lamella;
p
.
e
. = posteroexternal lamella;
p
.
i
. = posterointernal lamella.
FIGURE 7.
Cyphoderus caatinguensis
sp. nov.
abdominal appendages:
A
, Collophore anterior side;
B
, Collophore posterior side;
C
, Collophore lateral flap;
D
, Distal part of manubrium and dorsal dens chaetotaxy of dens, dorsal side.
E
, Mucro and dens with distal feathered chaetae;
F
, Mucronal teeth in detail, ‘*’ marks the apical smooth chaeta.
Anterior face of collophore (
Figs 7A–C
) with 2–3 ciliate chaetae, none of them clearly thicker than the others (
Fig. 7A
), posterior face with 3 ciliate chaetae (1 unpaired), 2 smooth small spines and 1–3 long, smooth chaetae (
Fig. 7B
). Lateral flap with 2 smooth chaetae (
Fig. 7C
).
Dorsal side of manubrium with about 60+60 chaetae. Manubrial plate with 2 chaetae and 2 pseudopores (
Fig. 7D
). Dens dorsally with 8–10 inner and 8 outer feathered chaetae, with regular ciliate chaetae between the feathered ones; 1 inner smooth or ciliate chaeta near mucro (
i1
); apex of dens with 1 long, robust feathered chaeta, at least twice as long as the mucro length (
Fig. 7E
). Mucro of the
tridenticulati
group, teeth formula as
aAi
, apical tooth (
a
) followed by a well-developed tooth (
A
) plus two paired reduced teeth (
i
) on the inner and outer lamellae (
Fig. 7F
). Ratio of mucro:dens:manubrium of
holotype
= 1:5.7:7.83.
Etymology.
The species is named after the Caatinga biome, where Boa cave is located.
Remarks.
The new species is unique within the genus by the combination of the following characters: ungues basal posterior tooth much larger than basal anterior tooth, unpaired apical tooth present, long and filamentous, tenent hairs capitate; femur III with smooth spine-like smooth chaetae; posterior face of collophore with 3 ciliate chaetae (1 unpaired), 2 small, smooth spines and 1 long, smooth distal chaeta; dens dorsally with 8–10 inner and 8 outer feathered chaetae; mucro short, of the
tridenticulati
group, with tooth formula as:
aAi sensu
Delamare-Deboutteville (1948)
.
Cyphoderus caatinguensis
sp. nov.
resembles other Neotropical species of the
tridenticulati
group with similar mucronal teeth formula (
aAi
or
aAA
). However, the new species can be distinguished from all of them by the combination of the presence of a single
m
chaeta on the labial basomedian field and a reduced spiny
l2
on the basolateral field, one central macrochaeta on the Abd. IV, ungues with an unpaired apical tooth, long and filamentous, and dens dorsal chaetotaxy (see
Table 1
). Considering the mucronal morphology and labial and Abd. IV chaetotaxy,
C. manuneru
Bernard, Soto-Adames & Wynne, 2015
is arguably the closest Neotropical species to
Cyphoderus caatinguensis
sp. nov.
, but they can be distinguished from each other by the number of spine-like chaetae on the trochanteral organ (
16–19 in
C
.
caatinguensis
sp. nov.
vs
.
10 in
C
.
manuneru
), absence of the ungual unpaired apical tooth in
C. manuneru
(present and filamentous in the new species), tenent hair shape (capitate in the new species
vs.
acuminate in
C. manuneru
) and number of the inner and outer dorsal feathered chaetae on dens (8–10 +
8 in
C
.
caatinguensis
sp. nov.
vs
. 4 +
7 in
C
.
manuneru
). Further comparisons between the Neotropical species of the
tridenticulati
group are provided in
Table 1
.
It is noteworthy the new species’ absence of pigments and eyes do not constitute any troglomorphism, since such morphology is shared among all
Cyphoderini
, which can live in many different habitats, including epigeic environments (
Delamare-Deboutteville 1948
;
Thibaud & Najt 1987
;
Oliveira
et al.
2023
). On the other hand, the strong modifications of the inner teeth seen in the ungues of
C
.
caatinguensis
sp. nov.
may actually represent troglomorphic traits, as discussed by
Christiansen (1961)
, despite the new species having tenent hairs capitate, a feature that suggests an edaphic life form. We sampled the entrance of the Boa cave and its external surroundings, as well as several other caves in the region, and did not find any specimens of the new species. This absence provides good evidence of a troglobitic species with a very restricted distribution.
Habitat, threats and conservation status.
Boa cave stands as the sole documented habitat of
Cyphoderus caatinguensis
sp. nov.
It boasts relatively expansive dimensions for the region, spanning approximately 340 meters in length and encompassing a volume exceeding
10,000 m
3 (
Fig. 1E
). However, its access is limited by a narrow, vertical entrance situated at the base of a sinkhole. Consequently, the microclimate within the cave is characterized by elevated temperatures, high humidity, and remarkable stability.
This cave has only a small isolated subterranean stream present at its lowest level. Consequently, the primary organic resources for cave fauna consist of extensive patches of guano deposited by thousands of
Chiroptera
, including the hematophagous hairy-legged vampire bat (
Diphylla ecaudata
Spix
) common vampire bat (
Desmodus rotundus
(Geoffroy Saint-Hilaire))
, the frugivorous flat-faced fruit-eating bat (
Artibeus planirostris
(Spix))
and the omnivorous pale spear-nosed bat (
Phyllostomus discolor
Wagner
) (
Vargas-Mena
et al.
2018
).
Although Boa Cave and its immediate environs exhibit a relatively preserved state, the limestone outcrop housing the cave has undergone significant alteration owing to irregular limestone mining activities. Furthermore, there are additional areas in the vicinities which have been impacted, mainly due to deforestation and agricultural practices. However, these alterations are situated at a distance from the cave, and it cannot be definitively stated that they are adversely affecting its fauna. Consequently, due to the uncertainties regarding the potential impacts of these human activities on
C. caatinguensis
sp. nov.
could be classified for now as a Data Deficient (DD) species, according to the International Union for Conservation of Nature’s method for assessing the risk of extinction (
IUCN 2022
).