Studies in Liocranidae (Araneae): a new afrotropical genus featuring a synapomorphy for the Cybaeodinae
Author
Jan Bosselaers
Author
Rudy Jocque
text
European Journal of Taxonomy
2013
2013-03-11
40
1
49
journal article
http://dx.doi.org/10.5852/ejt.2013.40
f0d32c6d-abb8-428a-aa91-9b4a4ce7b2ae
1036678
99B180D2-CCD2-4171-B640-E3EB68F94E2B
Cteniogaster nana
sp. nov.
urn:lsid:zoobank.org:act:B0321C9D-7120-407A-BAAF-BCF85186FDA0
Figs 3D-F
,
12H-J
,
14
; Appendix 1B
Diagnosis
Cteniogaster nana
sp. nov.
differs from all other
Cteniogaster
gen. nov.
species by its small size and by the male palp with a blunt, dorsally bent RTA, a relatively large and broad prolaterally inserted embolus, a small sclerotised apical conductor and a small and subtriangular retrolaterally inserted MA.
Etymology
The species name is derived from the Latin
nanus
, dwarf, and refers to the small size of the present species.
Type material
Holotype
Ƌ
:
TANZANIA
,
E. Usambara Mts., Amani
,
5°5.7’S
38°38’E
,
28 Oct.-9 Nov.
1995,
950 m
asl,
pitfalls
,
Griswold C.
,
Scharff N
. &
Ubick D.
(
CAS
)
Paratype
1
Ƌ
: together with
holotype
.
Description
Male (holotype)
TOTAL LENGTH. 1.74. Carapace length 0.74, width 0.58, unicoloured pale yellow, unbordered (
Fig. 3C
). Fovea pronounced, length 0.08, anterior end 0.53 from front end of carapace. MOQ length (when eight eyes present) 0.05, anterior width 0.02, posterior width 0.06. AER width 0.11, PER width 0.15. Median eyes with a strong tendency towards reduction, one specimen with reduced median eyes, the other having only four eyes (
Fig. 12J
). AME very small (1/6 of ALE diameter) or absent, PME very pale and strongly reduced (1/8 of ALE diameter) or absent, PLE 2/3 of ALE diameter. Both eye rows (if ME are present) straight from above. Clypeus vertical, equal to 1/3 of ALE diameter. Chilum indistinct. Sternum yellow, unbordered (
Fig. 3D
), length 0.47, width 0.39. PCT indistinct.
ABDOMEN. Pale cream dorsally (
Fig. 3F
) with traces of a weak, diffuse anterior do scutum and ventrally with an oblong, sclerotised patch carrying strong modiFed setae in posterior half (
Fig. 3 E
). Spinnerets as for the genus in general. Legs pale yellow (
Fig. 3D, F
). Retrocoxal hymen pronounced, oval and white. Trochanter notch indistinct in legs I and II, pronounced in legs III and IV. Very sparse ve terminal preening brushes on mt III and IV. Tarsus IV slightly bent. Leg spination as in Appendix 1B.
LEG MEASUREMENTS:
fe |
pa |
ti |
mt |
ta |
Total
|
I
|
0.53 |
0.24 |
0.39 |
0.29 |
0.28 |
1.72 |
II
|
0.45 |
0.22 |
0.37 |
0.28 |
0.28 |
1.59 |
III
|
0.42 |
0.14 |
0.29 |
0.32 |
0.29 |
1.46 |
IV
|
0.55 |
0.21 |
0.47 |
0.50 |
0.39 |
2.13 |
MALE PALP. With a blunt, dorsally bent RTA, a relatively large and broad prolaterally inserted pointed embolus, a small sclerotised apical conductor, and a pointed, small and subtriangular retrolaterally inserted MA.
Female
Unknown.
Distribution
Tanzania
,
East Usambara mountains
,
950 m
asl.
Discussion
Phylogenetic analyses
The preferred consensus tree for 27 species known from both sexes, with node numbers, state changes for 47 characters and Goloboff Ft Bremer support values (as reported in TNT) in italics below branches is illustrated in
Fig. 1
. Each ambiguity on the tree was optimized in isolation, in order to avoid scoring character states for absent structures, and also because only a combination of ACCTRAN and DELTRAN optimisation can produce the most robust proposal for a supposed homology. Indeed, the use of ACCTRAN only, as is often preferred, does not always maximize parallel loss of complex traits over convergent gains (
Agnarsson & Miller 2008
). Of the Fve ambiguous characters shown on the preferred tree in
Fig. 1
, DELTRAN optimisation was preferred for characters 19, 38 and 72, ACCTRAN for character 37, and only unambiguous changes are shown for character 22.
Homoplasy in the data matrix which produced the preferred tree is quite acceptable: 22 out of 99 characters are completely free of homoplasy.
Sanderson & Donoghue (1989
: 1785, Fg. 1) performed a polynomial regression analysis on data from 60 cladistic analyses, and derived the following equation based on them: ci = 0.90 - 0.022×(number of taxa) + 0.000213×(number of taxa)2. Applying this equation, 27 taxa would yield a ci value of 0.461, quite similar to the actual ci value of 0.412 obtained for the consensus tree in the present analysis.
The ingroup (clade 1) is supported on the preferred tree by the absence of apical do spines on fe III and IV (11:0, not shown in
Fig. 1
, reversed in
Cybaeodes marinae
Di Franco, 1989
and in clade 14), the presence of a distal spine on the male palpal pl edge [27:1, absent in
Scotina palliardii
(L. Koch, 1881)
], absence of true claw tufts (36:0), the presence of tenent hairs at the tip of tarsi (37:1, reversed in clades 3 and 14, but present in
Apostenus
), a simple sternal border (42:0, reversed in
Toxoniella
), two retromarginal cheliceral teeth (43:0, more than two in
Toxoniella
), a shaggy hair in front of the fang base (44:1, reversed in
Toxoniella
), a conspicuous serrula on the endites (48:0), a Fat carapace (50:1, changed to slanting in clade 20), modiFed PME (57:1, reversed in clade 14), the MOQ widest posteriorly (58:1), curved strong hairs frontally on abdomen (60:1), no epigastric sclerite (62:0, 70:0), laterally compressed female PMS (71:1, changed to slender in clade 4 and to stout and subtriangular in clade 11), absence of a coiled sperm duct (79:0), a membranous conductor (81:1, reversed in
Cteniogaster conviva
sp. nov.
and
Agraecina lineata
(Simon, 1878)
, unapplicable in clade 20), a simple conductor (82:0, complex in
C. conviva
sp. nov.
, unapplicable in clade 20), MA present (83:1), subtegulum pl (89:0), anterior hood present in epigyne (94:1, reversed in
Hesperocranum rothi
Ubick & Platnick, 1991
, and in clade 15) and anterior epigynal entrances (97:0). We consider clade 1 to represent the family
Liocranidae
. It is divided in two sister clades in the present analysis: clade 2 and clade 7 (
Fig. 1
).
Fig. 9.
Cteniogaster toxarchus
gen. et sp. nov.
A.
Ƌ, habitus, dorsal view.
B.
Idem, abdomen, ventral view.
C.
Idem, palp, ventral view.
D.
Idem, retrolateral view.
E.
Epigyne, ventral view.
F.
♀, carapace, lateral view.
G.
Ƌ, carapace, lateral view.
H.
♀, carapace, dorsal view. Scale bars: A-C, F-H = 0.5 mm, C-E = 0.25 mm.
Fig. 10.
Cteniogaster hexomma
sp. nov.
A. Ƌ,
habitus, dorsal view.
B.
Idem, abdomen, ventral view.
C.
Idem, palp, ventral view.
D.
Idem, retrolateral view.
E.
Epigyne, ventral view.
F. ♀,
carapace, anterior view. Scale bars: A-B, F = 0.5 mm, C-E = 0.25 mm.
Clade 2 is interpreted as subfamily Liocraninae and is supported on the preferred tree by the presence of large erectile bristles in the ve scopulae of legs I and II (5:1), ventral scopulae on ti I and II (33:1) and a pl terminal lobe on the male palpal ti (91:1). Clade 4 (
Mesiotelus
Simon, 1897
and
Liocranum
L. Koch, 1866
) is further characterised by slender female PMS carrying only a single large spigot (71:0, 72:0,
contra
Wunderlich 2008
: 489).
Clade 7 is interpreted as subfamily Cybaeodinae and is supported on the preferred tree by the presence of a trochanter notch (3:1, reversed in
Apostenus
), the presence of bent male tarsi (8:1), presence of do spines on ti III (at least in females) and IV (17:1, 18:1), cylindrical ALS in males (65:1, reversed in clade 17), and presence of EPGS in males (69:1, reversed in clade 20). Although present in some
Clubionidae
as well (see discussion of character 69, above), the presence of EPGS seems to be an interesting apomorphy for the subfamily Cybaeodinae. The character is lost in the genera
Apostenus
and
Scotina
, most probably due to their small size.
Cybaeodes
Simon, 1878
(clade 8) holds a basal position within Cybaeodinae in the present analysis, supported by two rows of more than Fve large spigots on female PMS (paralleled in
Toxoniella
) and a small dorsal bristle mat on the male palpal cymbium (76:1).
Toxoniella
(clade 10) differs from all other members of clade 1 by a number of reversals, being a rebordered sternum (42:1), more than two retromarginal cheliceral teeth (43:1) and absence of a shaggy hair in front of the cheliceral fangs (44:0), but the genus Fts within the clade for all other important characters, including the presence of an epigynal anterior hood (94:1).
Toxoniella
shares with
Cybaeodes
,
Hesperocranum
Ubick & Platnick, 1991
and
Sagana
Thorell, 1875
the laterally compressed female PMS (71:1), and with
Cybaeodes
and
Sagana
a large number of tarsal tenent hairs (38:2). Both characters appear plesiomorphic within the family. Within Cybaeodinae,
Toxoniella
shares the presence of EPGS (69:1) with most other genera.
Toxoniella
is herewith transferred to
Liocranidae
. None of the other genera currently included in
Gallieniellidae
is reported to possess EPGS in males.
Cteniogaster
gen. nov.
also Fts well within Cybaeodinae, but differs from related genera by the wide patellar indentations (6:1, 7:1, paralleled in
Apostenus
), the presence of one mt IV plv and rlv spine (21:1), two pairs of tenent hairs (38:1), and the presence of ve abdominal setae in males (63:1, paralleled in
Agroeca brunnea
(Blackwall, 1833)
and
Agrocea
cuprea Menge, 1873
(clade 19) and in
Apostenus fuscus
Westring, 1851
). The fact that these male ve abdominal setae occupy a well delimited small oval area (64:1) is an autapomorphy for the genus. Clade 14 is supported by the absence of mt III and IV vt spines (23:0, reversed in clade 20) and the presence of circular PME (57:0). Clade 16 is supported by the presence of a subtegular locking lobe (78:1), complemented in clade 17 (the genera
Agroeca
,
Apostenus
and
Scotina
) by a tegular locking lobe (77:1) and conical ALS in males (65:0). The genus
Agroeca
(clade 18) is supported by a biFd MA (84:1, paralleled in
Sagana rutilans
Thorell, 1875
) and a Fat, ribbonshaped embolus (87:4). Clade 20, consisting of small, derived Cybaeodinae, is distinguished by plv spines on fe I (9:1), a slanting carapace (50:0), and absence of a conductor (80:0) and of EPGS (69:0).
Apostenus
is further characterised by the presence of one pair of tenent hairs (38:0), widely separated PME (59:2) and the absence of ST2 (98:0). Its sister genus
Scotina
features equidistant PE (59:1) and a whip-shaped embolus (87:5).
While some characters (36:0, 48:0, 58:1, 60:1, 62:0, 70:0, 79:0, 83:1, 89:0, 97:0) are constant throughout
Liocranidae
, others (44:1, 57:1, 65:1, 69:1, 94:1) show reversal in some clades.
Reversals and secondary losses of characters are particularly common on the preferred tree in the genus
Toxoniella
and in clade 20, which groups the genera
Apostenus
and
Scotina
. Apart from the three reversals mentioned above,
Toxoniella
has no plv and rlv spines on female ti I (14:0) and has male and female PLS close together (68:0 and 73:0, paralleled in clade 3 and in clade 4, respectively). In clade 20, apart from the already mentioned absence of EPGS (69:0) and a conductor (80:0), the number of mt III plv and rlv spines is reduced (20:0, paralleled in
Cteniogaster
gen. nov.
and
Hesperocranum
), mt III and IV have ve terminal spines (23:1), feathery hairs are absent (30:0, paralleled in
Hesperocranum
,
Liocranoeca
and
Agraecina
), there is no apical maxillar hair tuft (49:0, paralleled in
Cteniogaster
gen. nov.
,
Hesperocranum
and
Liocranoeca
), and PME and PLE are close to each other (59:1 or 59:2). Moreover,
Apostenus
has no trochanter notch (3:0) and no ST2 (98:0). The presence of male modiFed ve abdominal setae (63:1) appears to have evolved convergently in
Cteniogaster
gen. nov.
and in some
Agroeca
and
Apostenus
(
Wunderlich 2008: 489
)
. The character was already present in the eocene
Apostenus spinimanus
. The presence of tenent hairs (37:1) also shows a peculiar distribution on the preferred tree, being restricted to the genera
Sagana
,
Cybaeodes
,
Toxoniella
,
Cteniogaster
gen. nov.
, and
Apostenus
. While
Sagana
has 9 and
Cybaeodes
(see
Bosselaers 2009
) and
Toxoniella
5 pairs of tenent hairs,
Cteniogaster
gen. nov.
has only two pairs (
Fig. 11C-E
) and recent
Apostenus
only one (
Fig. 11G
). However, the extinct
Apostenus spinimanus
, most probably congeneric with recent species, has three pairs (
Fig. 11F
,
contra
Wunderlich 2004
: 1627). Based on the presence of tenent hairs, modiFed male ve abdominal setae, an epigynal anterior hood and the other characters listed above for clade 1 (with the exception of a sclerotised conductor for
Cteniogaster conviva
sp. nov.
), the new genus
Cteniogaster
gen. nov.
is placed in
Liocranidae, Cybaeodinae.
Fig. 11. A.
Cteniogaster toxarchus
gen. et sp. nov. Tip of male palp, ventral view.
B-D.
Cteniogaster hexomma
sp. nov.
B.
Tip of male palp, ventral view.
C.
Tip of male tarsus IV, retrolateral view.
D.
Bent male tarsus IV.
E.
Cteniogaster toxarchus
gen. et sp. nov., tip of male tarsus IV.
F.
Apostenus spinimanus
(Koch & Berendt, 1854)
, tip of male tarsus IV.
G.
Apostenus fuscus
Westring, 1851
, tip of male tarsus IV.
H.
Arabelia pheidoleicomes
Bosselaers, 2009
, tip of female tarsus IV. Scale bars: D = 200 μm; A-C, E-G = 100 μm. Abbreviations: C = conductor; E = embolus; MA = median apophysis.
Fig. 12. A-E.
Cteniogaster conviva
sp. nov.
A.
Ƌ, palp, ventral view.
B.
Idem, retrolateral view.
C.
Epigyne, ventral view.
D.
Idem, other specimen.
E.
Eye region of male, anterior view.
F-G.
Cteniogaster sangarawe
sp. nov.
F.
Epigyne, ventral view.
G.
Idem, other specimen.
H-J.
Cteniogaster nana
sp. nov.
H.
Ƌ, palp, ventral view.
I.
Idem, retrolateral view.
J.
Eye region of male, anterior view.
K.
Cteniogaster taxorchis
sp. nov.
Epigyne, ventral view.
L.
Cteniogaster lampropus
sp. nov.
Epigyne, ventral view. Scale bar = 250 μm.
The present phylogenetic analysis does not produce an unequivocal autapomorphy for
Liocranidae
. However, a combination of a number of non-homoplasious character changes mentioned above for clade
1 in
the discussion of phylogenetic Fndings, offers signiFcant potential for recognising genera as
Liocranidae
. No doubt, most of these character states (11:0, 27:1, 42:0, 43:0, 44:1, 48:0, 57:1, 58:1, 60:1, 89:0, 97:0) are not unique to
Liocranidae
and probably plesiomorphic on a wide scale or only apomorphic to a larger clade in which
Liocranidae
will prove to be embedded. Nevertheless, we consider a combination of a sizable number of these character states as the best approach available to date towards recognising
Liocranidae
: the absence of true claw tufts (36:0), the presence of tenent hairs (37:1), the absence of extensive abdominal ve sclerotisation, at least in females (70:0), the presence of a simple, membranous conductor as well as a MA in the male palp (81:1, 82:0, 83:1) and an epigyne with an anterior hood (94:1). The attribution of the liocranid genera included in the present analysis to subfamilies Liocraninae and Cybaeodinae can be considered robust, as both supraspeciFc taxa are supported by apomorphies within
Liocranidae
(5:1, 91:1 and 3:1, 8:1, 17:1, 18:1, 69:1, respectively). The presence of EPGS in males (69:1) is the main character on which the transfer of
Toxoniella
to
Liocranidae, Cybaeodinae
is based. The family
Gallieniellidae
is poorly deFned: porrect chelicerae, the only synapomorphy found in Platnick’s cladogram (
2002
: 9), also occur in other araneomorph spider families, such as
Clubionidae
and
Theridiidae Sundevall, 1833
. In addition,
Haddad et al. (2009
: 16) mention small male AME, a recurved PER, conical ALS and a short cymbium tip, but most of these characters reverse somewhere within the
Gallieniellidae
clade and none is unique to the family. The presence of tenent hairs (37:1), a character found in the majority of
Liocranidae
, is also encountered in the gallieniellid genera
Drassodella
Hewitt, 1916 (
Warui & Jocqué 2002: 314
)
and
Austrachelas
Lawrence, 1938
, although in the latter they are only present on the posterior two pairs of legs, similar to what is described in
Raven & Stumkat (2002)
for some
Clubionidae
. However, no other gallieniellid has cylindrical ALS provided with EPGS in males, and this character, in combination with the above mentioned set of characters commonly encountered in
Liocranidae
, is judged sufFcient to justify the transfer.
As far as the other liocranid genera listed in
Platnick (2012)
are concerned, some conclusions can be drawn and a few transfers proposed.
Argistes
Simon, 1897
and
Sphingius
Thorell, 1890
most probably belong in
Liocranidae
, given the presence of tenent hairs (
Deeleman-Reinhold 2001: Fgs. 639; personal observation
), a simple conductor and a MA. As long as the conspeciFcity of the male described by
Bosmans (2011: 20, Fgs. 15-16)
with females of
Arabelia
Bosselaers, 2009
is not proved beyond doubt, it seems better to keep the genus as
Liocranidae
incertae sedis
, due to the presence of Fve pairs of tenent hairs and an anterior epigynal hood, as well as the complete absence of abdominal sclerotisation. Pending a generic revision, the same classiFcation is defended for
Rhaeboctesis
Simon, 1897
, given the absence of true claw tufts and abdominal sclerotisation, as well as the presence of a simple conductor and a MA.
Andromma
Simon, 1893
does not Ft well in
Liocranidae
as deFned here, due to the presence of true claw tufts and the absence of a MA and anterior epigynal hood. It is likely to belong in
Corinnidae
, but since a comprehensive cladistic analysis of a larger number of liocranid and corinnid genera is not yet available, it is best to keep it in
Liocranidae
as
incertae sedis
.
Paratus
Simon, 1898
, which lacks a MA (
Marusik et al. 2008
;
Zapata & Ramírez 2010
) was placed in a subfamily of its own by Marusik et al., based, apart from the general character states already mentioned above for clade 1, on an insufFent number of characters (
2008
: 51), such as absence of a retrocoxal hymen (also absent in
Cybaeodes
,
Liocranoeca
,
Neoanagraphis
and
Sagana
, see Appendix 3), embolus inserted centrally on tegulum, very simple epigyne and abdomen with guanine spots. It seems best to keep the genus as
Liocranidae
incertae sedis
until a thorough analysis has been performed.
Sudharmia
Deeleman-Reinhold, 2001
, with its almost unsclerotised female abdomen and male palp with pl subtegulum and simple, membranous conductor (but lacking MA) is also considered
Liocranidae
incertae sedis
here. Literature data on
Heterochemnis
F.O.P. Cambridge, 1900,
Laudetia
Gertsch, 1941
,
Liparochrysis
Simon, 1909
and
Mesobria
Simon, 1897
, genera that have never been thorougly diagnosed or revised, are insufFcient to judge on their afFnities: these four genera are best kept in
Liocranidae
incertae sedis
for the time being.
Sesieutes
Simon, 1897
, will be transferred to
Corinnidae, Phrurolithinae Simon, 1903
by Dankittipakul & Deeleman-Reinhold (in press), and we propose the same transfer for the genera
Jacaena
Thorell, 1897
,
Plynnon
Deeleman-Reinhold, 2001
and
Teutamus
Thorell, 1890
, based on their inFated tegulum, absence of MA, modiFed male palpal fe, simple epigyne without anterior hood and abdominal sclerotisation (
Deeleman-Reinhold 2001
). A comparison of Simon’s specimens of
Prochora lycosiformis
(O.P.-Cambridge, 1872) with the published illustrations of the male and female copulatory organs of
Itatsina praticola
(Bösenberg & Strand, 1906)
clearly shows that the monospeciFc genus
Itatsina
Kishida, 1930
is congeneric with the equally monospeciFc
Prochora
Simon, 1886
, although both species are not identical. Consequently,
Prochora praticola
comb. nov.
is transferred to
Miturgidae Simon, 1885
here, because of its biFd RTA, combined with a cymbium with a rl groove lined with a fringe of setae and a basally inserted embolus encircling the tegulum (
Song et al. 1999
: Fg. 238J-L).
Coryssiphus
Simon, 1903
and
Donuea
Strand, 1932
will be transferred to other families in forthcoming publications. The
holotype
of
Montebello tenuis
Hogg, 1914
was studied by Ovtsharenko (personal communication) and turned out to be a juvenile, damaged specimen with eyes and spinnerets reminiscent of
Gnaphosidae Pocock, 1898
. The genus is transferred to
Gnaphosidae
incertae sedis
here.
Fig. 13.
Map showing all localities of georeferenced
Liocranidae
in the collections of MRAC:
Cteniogaster
gen. nov.
(●), all other
Liocranidae
(Ǫ) (n = 315).
Fig. 14.
Distribution maps.
A.
Cteniogaster hexomma
sp. nov.
(●),
C. toxarchus
gen. et sp. nov. (*).
B.
Cteniogaster lampropus
sp. nov.
(▲),
C. nana
sp. nov.
(Ǫ).
C.
Cteniogaster taxorchis
sp. nov.
(□),
C. conviva
sp. nov.
(■),
C. sangarawe
sp. nov.
(Δ).
Wunderlich’s (
2011
: 108) proposal to include
Liocranidae
in
Zoridae
O.P.-Cambridge, 1893 and transfer
Cybaeodes
to
Gnaphosidae
is rejected because it is based on insufFcient data and is not supported by a cladistic analysis. Moreover, the four zorid species studied by the authors,
Zora spinimana
(Sundevall, 1833)
,
Tuxoctenus gloverae
Raven, 2008
,
Argoctenus
sp. and
Hestimodema
sp., apart from lacking tenent hairs and male EPGS, all share a set of characters not encountered in
Liocranidae
: a PER with large eyes in two rows, as in
Ctenidae
and
Lycosidae Sundevall, 1833
, PME close together, thick claw tufts, an anteriorly strongly narrowed carapace, a male palpal cymbial tip with modiFed thick setae as described in
Raven (2008: 352)
, a RTA with a Fattened basal membranous wing, an epigyne without anterior hood and a vulva without ST2 and with posterior globular ST1 connected to tortuous insemination ducts.
The proposals formulated here limit
Liocranidae
to 25 genera, including
Cteniogaster
gen. nov.
,
Toxoniella
and the recently described genus
Vankeeria
Bosselaers, 2012
, of which the latter can be considered
incertae sedis
(
Bosselaers 2012
). Of these genera, four belong in Liocraninae, nine can be attributed to Cybaeodinae, and twelve remain
incertae sedis
, stressing the need for additional revisions and a more thourough analysis of
Liocranidae
and related dionychan ground spiders.