Three new species of Dolichoiulus millipedes from the underground of Gran Canaria, with notes on the circumscription of the genus (Diplopoda, Julida, Julidae)
Author
Enghoff, Henrik
text
European Journal of Taxonomy
2012
2012-05-24
15
1
12
journal article
21838
10.5852/ejt.2012.15
cf05c28d-74ba-474f-a669-3145aa58b691
2118-9773
3857818
DAAF887A-5637-4951-B4A7-B47029605AE9
Dolichoiulus longunguis
sp. nov.
Fig. 5
Diagnosis
A blind species of
Dolichoiulus
. Differs from other blind
Dolichoiulus
species as shown in
Table 1
. Differs from the other blind
Dolichoiulus
on Gran Canaria in size (
Figs 1
,
5
). Differs from
D. typhlocanaria
sp. nov.
and
D. oromii
sp. nov.
in having broader anterior gonopods, further from
D. oromii
sp. nov.
in lacking metazonital setae and in having only marginal preanal pilosity, and further from
D. typhlocanaria
sp. nov.
in lacking a terminal projection on the mesal ridge of the anterior gonopod. Differs from the widespread
D. typhlops
by being slenderer (
Fig. 1
,
cf
.
Enghoff 2002
: fig. 1).
Etymology
The name (noun in apposition) meaning “long claw” and refers to a distinguishing character of this species.
Material studied
Holotype
♂
, GRAN CANARIA,
Mina Los Roques
, UTM 28R 4476/30943 (
28°0’0’’N
,
15°31’56”W
),
18 Mar. 2012
,
M. Naranjo
leg. (
DZUL
).
Paratype
1 ♀
, same loc.,
23 Jan. 2012
, M. Naranjo leg. (
DZUL
).
Total material
1 ♂
,
1 ♀
(analyzed).
Description
♂
: L
13 mm
, H
0.71 mm
, L/H 19, 51 podous rings + 2 apodous rings in front of telson.
♀
: L
13 mm
, H
0.72 mm
, L/H 18, 49 podous rings + 1 apodous ring in front of telson.
COLOUR. The preserved specimens are uniform pale brown.
HEAD. No eyes. 4 supralabral setae. Setae on gnathochilarial stipes: 3 apical, 4 (
♂
) / 0 (
♀
) nonapical. Length of antennae 138% of H in
♂
, 126% of H in
♀
.
BODY RINGS. Prozonites not furrowed. Metazonites unvaulted, striae quite indistinct dorsally (not studied with SEM). Ozopore
c
. 0.4 metazonite length behind suture. Limbus not studied (requires SEM).
LEGS. Length 65% of H in
♂
, 61% of H in
♀
. Claw: length 11% of leg, length/height 4.5-5.4. Accessory claw 0.3-0.4× shorter than claw.
PREANAL RING. Without a projection, pilosity marginal.
Male
MANDIBULAR STIPITES. Without lobes.
Fig. 5.
Size diagram for
Dolichoiulus oromii
sp. nov.
and
D. longunguis
sp. nov.
The diagram shows number of podous (leg-bearing) body rings (p.r., x axis) and vertical body diameter in mm (y axis). For a given number of podous rings
D. oromii
sp. nov.
is thicker than
D. longunguis
sp. nov.
but thinner than
D. typhlocanaria
sp. nov.
(see Fig. 1); specimens of
D. oromii
sp. nov.
from East-Central Gran Canaria are thicker than those from the Northwest (El Sao), and females are thicker than males.
LEGS. Second pair with ventral pads on tibia only. Postfemoral pads absent, tibial pads tiny on midbody legs. Second pair with coxal pores.
ANTERIOR GONOPODS. Indistinguishable from the one shown in
Fig. 3D
, broader than in
D. typhlocanaria
sp. nov.
and
D. oromii
sp. nov.
Mesal ridge without a terminal projection. Lateral prominence distinct. Bowl broad, lateral margin regularly convex. Apical denticles distinct.
POSTERIOR GONOPODS. Indistinguishable from those of
D. typhlocanaria
sp. nov.
and
D. oromii
sp. nov.
Female
RECEPTACULUM SEMINIS. A stalked sphere (as in
Enghoff 1992
: fig. 48).
Distribution and habitat
Endemic to Gran Canaria. Known only from the
type
locality in the east-central part of the island, Collected in an artificial gallery. The short legs and long claws in this species may suggest that it is a soil-digger species rather than a true cave species (
cf
.
Enghoff 1982
). Among other
Dolichoiulus
species claws as long as those of
D. longunguis
sp. nov.
are found only in
D. blancatypa
(
Enghoff, 1992
)
comb. nov.
from Tenerife, which also has short legs and is a soil-dweller (
Enghoff 1992
).
Discussion
It is perhaps not surprising that the first new
Dolichoiulus
species to be found after
Enghoff (1992)
are from the underground of Gran Canaria. Although caves are scarce on Gran Canaria, there are many deep artificial old galleries such as Mina de los Roques which have produced an interesting subterranean fauna (
Naranjo
et al
. 2009
). Also, the mesovoid (or mesocavernous) shallow stratum (MSS) is richly represented, and recent collecting activities here have revealed a rich endemic fauna of, e.g.,
Lagynochthonius
Beier, 1951
pseudoscorpions,
Symploce
Hebard, 1916
cockroaches and
Oromia
Alonso-Zarazaga, 1987
weevils (
Oromí
et al
. 2010
;
Mahnert, 2011
). The abundant artificial caves and MSS spots not yet prospected suggest that the underground of Gran Canaria still has not been exhausted in terms of new millipede species.