Venation pattern and revision of Orthoptera sensu nov. and sister groups. Phylogeny of Palaeozoic and Mesozoic Orthoptera sensu nov.
Author
Béthoux, Olivier
Author
Nel, André
text
Zootaxa
2002
96
1
88
journal article
10.5281/zenodo.156112
f86b2225-fd69-4d14-888f-1656863a3244
11755326
156112
Genus
Gerarus
Scudder,
1885
.
Type
species.
Gerarus vetus
Scudder,
1885
.
Composition. We restrict the genus to the species
Gerarus vetus
Scudder,
1885
,
Gerarus bruesi
Meunier,
1909
,
Gerarus fisheri
(
Brongniart,
1885
)
Burnham,
1983
, G
erarus collaris
Handlirsch,
1906
, and
Gerarus danielsi
Handlirsch,
1906
(see above).
Diagnosis.
Burnham (
1983
)
compared
Gerarus
to
Nacekomia
,
Progenentomum
,
Genentomum
and
Gerarulus
.
KukalováPeck & Brauckmann (
1992
)
did not give a new diagnosis of the genus. Thus we propose a new diagnosis, based on forewings characters: ScP long, straight, anteriorly pectinate; branches of ScP simple or shortly ramified;
RP
with few distal branches; MA differentiated into MA
1
and MA
2
; MA
1
generally connected to
RP
by a short crossvein or shortly fused; MP ramified very proximally; CuPa present, more or less weak; CuPb ramified with an anterior branch long or reduced, and either connected or not to CuPa.
Note. The very long, spiny pronotum of numerous
Gerarus
spp. is a strong synapomorphy (
Burnham
1983
;
KukalováPeck & Brauckmann
1992
) but is unknown in
Gerarus bruesi
, thus it is not possible to determine if it is at the family or genus level.
Discussion.
Gerarus vetus
as figured by
KukalováPeck & Brauckmann (
1992
: figs. 4,10,13)
has a simple MP, suggesting closer relationships with
Orthoptera
than with
G. bruesi
and
G. danielsi
, which have an MP which is clearly and very proximally ramified. In his composite reconstruction of the
holotype
of
G. vetus
,
Burnham
(
1983
: fig.
4
) did not figure a simple but a forked MP vein. It is not certain if the
holotype
of
G. vetus
and the specimens studied by
KukalováPeck & Brauckmann (
1992
)
belong to the same species or even genus. Thus, the monophyly of this genus remains unclear.