Studies in the Liocranidae (Araneae): revision of Andromma Simon, 1893
Author
Bosselaers, Jan
D6AD7414-3540-4F06-8631-8873450AA90C
Royal Museum for Central Africa, Tervuren, Belgium.
dochterland@telenet.be
Author
Jocqué, Rudy
CF15016C-8CD1-4C9D-9021-44CA7DC7A5D5
Royal Museum for Central Africa, Tervuren, Belgium.
jocque@africamuseum.be
text
European Journal of Taxonomy
2022
2022-12-09
850
1
78
http://dx.doi.org/10.5852/ejt.2022.850.1997
journal article
207924
10.5852/ejt.2022.850.1997
49c26e4e-77d4-4c8e-9257-b1b034d8d5f9
2118-9773
7427642
E8AD897F-2076-4850-9520-BB79B1EAFFEA
Genus
Andromma
Simon, 1893
Type
species
Andromma aethiopicum
Simon, 1893
, by monotypy.
Diagnosis
Andromma
resembles
Hortipes
Bosselaers & Ledoux, 1998
by the peculiar retina of the AMEs which, as seen from above, is only visible in the median half of these eyes. It differs from it by the absence of a metatarsal sensory array on the legs I and II (
Bosselaers & Jocqué 2000
;
Ramirez 2014: 118
), by the smaller number of ventral spine pairs on the tibia and metatarsus I and II, by the flat carapace, which is not elevated in the thoracic region, and by the absence of a median apophysis on the male bulbus.
Andromma
also resembles the equally myrmecophilous
Arabelia
Bosselaers,
2009
in general somatic aspect, but differs from it by the absence of an anterior epigynal hood, by the smaller copulatory opening, by the absence of spermathecae II, by the complex, bipartite RTA of the male palp, and by the longer embolus. It differs from
Cybaeodes
by the bipartite RTA, and by the absence of enlarged piriform gland spigots on the ALS of males, and from
Paratus
Simon, 1898
by the flat carapace, by the shorter and less numerous ventral spine pairs on the tibia and metatarsus I and II, and by the absence of dorsal guanine spots on the abdomen.
Andromma
differs from
Liocraninae
in general by the absence of rows of large and erectile bristles with special basal sockets in the ventral scopulae of tibia, metatarsus and tarsus of legs I–III (
Ubick & Platnick 1991: 2
).
Description
Translation of original Latin description of
Simon (1893: 390)
Cephalothorax short and oval, rather convex, without fovea. Four eyes in a straight transverse line, the medians of medium size, the laterals small, minute in males. Clypeus about twice as high as diameter of median eyes. Strong chelicerae with a robust and long fang. Labium much wider than long, transversely semicircular and hardly reaching the middle of the endites. Endites broad and short, not much longer than wide, very blunt, inclined, not curved or transversely grooved. Sternum convex, broadly heartshaped, wider than long. Posterior coxae widely spaced. Leg formula 4123. Legs rather short, tarsi long and hardly shorter than metatarsi, the anterior ones slightly fusiform. Tarsi hardly scopulated, but with dense claw tufts. Tarsal claws shiny and slender, with a series of 5–6 teeth reaching to the apex. Anterior lateral spinnerets closely spaced, longer than posterior medians. Posterior lateral spinnerets also longer than medians, their apical segment at least ⅓ shorter than basal one (
Fig. 2F–G
).
Additional description data
In the remainder of the text,
Simon (1893: 387–389)
elaborated on the differences between
Andromma
and
Cybaeodes
or
Cithaeron
O. Pickard-Cambridge, 1872
(erroneously spelled
Cythaeron
in the text). This allows us to infer the following additional characteristics: legs reddish brown, spineless, tarsal claw tufts consisting of tenent hairs (
Forster 1970: 18
; Ubick & Vetter 2005: 69, 71).Anterior lateral spinnerets rather small and cylindrical, separated at the base by their diameter. Posterior median spinnerets of similar shape, as long as anterior laterals or longer. Posterior lateral spinnerets a bit thicker than anterior laterals and slightly more widely separated, resulting in a trapezoidal spinneret area, which is narrower anteriorly, contrary to the situation in gnaphosids, except the
Micaria
group (
Murphy 2007
). Posterior lateral spinnerets consisting of two segments, the apical one conical and at least one third shorter than the basal one. Female palp rather long, tibia much longer than patella, tarsus a bit longer than tibia and slightly fusiform. Male palpal tibia somewhat shorter than patella, with a bifid apophysis: a hook-shaped retrolateral apophysis (RTA) and a thicker ventral apophysis (VTA) with an anterior cavity. Simon also mentions a small tibial prolateral tooth, but we were unable to observe that in any of the species examined. Palpal tarsus longer than patella and tibia together, oval, large, convex, with a tip that largely exceeds the convex, simple bulbus. Abdomen covered in greyish silky hairs.
Remarks on original description
Simon’s original description understandably is solely based on the only species known to him at the time,
A. aethiopicum
. Unfortunately, this species is one of the least representative for the genus as a whole. The following four corrections are important to note:
1. While some species of
Andromma
have a sternum that is as wide as long (e.g., female of
A. deogratias
sp. nov.
,
A. bouvieri
and
A. ghesquierei
sp. nov.
), the sternum is longer than wide in most species of
Andromma
known to date.
Andromma aethiopicum
,
A. anacardium
sp. nov.
and the female of
A. raffrayi
are the only species within the genus with a sternum that is clearly wider than long.
2. Most species of
Andromma
have eight eyes. The only other species with significant eye reduction are
A. albinovani
sp. nov.
and
A. deogratias
sp. nov.
(
Fig. 2A–B
).
3. Most species of
Andromma
have at least some leg spines.
4.
Andromma
does have a thoracic fovea, as our habitus photographs show (
Figs 20A
,
22A
,
30A
). In very pale specimens, it may be difficult to see (
Fig. 5A
).
5. In his French description,
Simon (1893: 388)
refers to the claw tufts as “denses et formés de poils claviformes nombreux”. However, careful observation shows that these hairs are not clavate.
To the above can be added that the AMEs of
Andromma
are oriented divergently. As a consequence, the retina of the AMEs which, as seen from above, is only visible in the median half of these eyes. (
Fig. 2A–E
). Such AMEs are also present in
Hortipes
(
Bosselaers & Jocqué 2000
: figs 1–2),
Attacobius
Mello-Leitão,1925 (Corinnidae)
(
Platnick & Baptista 1995
: figs 7–8),
Piabuna
Chamberlin & Ivie, 1933
(Phrurolithidae)
(
Bosselaers & Jocqué 2002
: fig. 2f;
Chamberlin & Ivie 1933
: fig. 122),
Orthobula
Simon, 1897 (Trachelidae)
(
Marusik
et al
. 2013
: figs 1–2) and
Paratus
(Liocranidae)
(
Marusik
et al.
2008
: fig. 4), and others (
Bosselaers & Jocqué 2002
: table 1). Furthermore, the male palp has a tibial apophysis split into a ventral (VTA) and retrolateral (RTA) part as well as a globular bulbus without median apophysis (
Figs 4E–F
,
6D–E
). The epigyne presents conspicuous copulatory openings in most species (
Figs 5C–D
,
9C–D
) and the vulva generally has more or less globular spermathecae (
Figs 25C– F
,
30E–F
). The spermathecae have short, tubular fertilisation ducts running in posterior direction. These fertilisation ducts are accompanied by a sickle-shaped sclerite (Sss) oriented laterally or posteriorly (
Fig. 7D
;
Ledoux & Canard 1991
: fig. 36). Such sclerites should not be confounded with fertilisation ducts; they are commonly found in dionycha, e.g., in many
Gnaphosidae (
Grimm 1985
)
,
Apostenus
Westring, 1851 (Liocranidae)
(
Grimm 1986
),
Arabelia Bosselaers, 2009 (Liocranidae)
(Bosselaers 2009),
Cheiracanthium
Wagner, 1887 (Cheiracanthiidae)
(Bosselaers 2013),
Cteniogaster
Bosselaers & Jocqué, 2013
(Liocranidae)
(
Bosselaers & Jocqué 2013
),
Heser
Tuneva, 2004 (Gnaphosidae)
(Bosselaers 2010),
Hortipes
Bosselaers & Ledoux, 1998 (Corinnidae)
(
Bosselaers & Jocqué 2000
),
Metatrachelas
Bosselaers & Bosmans, 2010
(Trachelidae)
(
Bosselaers & Bosmans 2010
),
Paratrachelas
Kovblyuk & Nadolny, 2009 (Trachelidae)
(
Bosselaers
et al
. 2009
),
Rhaeboctesis
Simon, 1897 (Liocranidae)
(
Bosselaers & Jocqué 2002
), and
Trachelas
L. Koch, 1872 (Trachelidae)
(
Bosselaers
et al
. 2009
). However, these sclerites are never explicitly mentioned in the literature.
Engelhardt (1910: 73
, fig. 25) and
Osterloh (1922: 386
, fig. 36) mention sclerotised beams in the vulvae of
Platnickina tincta
(Walckenaer, 1802)
and
Allagelena gracilens
(C.L. Koch, 1841)
respectively, but these structures do not correspond to the sickle-shaped sclerites mentioned here.