Ants with Attitude: Australian Jack-jumpers of the Myrmecia pilosula species complex, with descriptions of four new species (Hymenoptera: Formicidae: Myrmeciinae)
Author
Taylor, Robert W.
text
Zootaxa
2015
3911
4
493
520
journal article
42325
10.11646/zootaxa.3911.4.2
83770aa6-52d7-4e4e-85d2-4126ca5c1cf0
1175-5326
68799
EDF9E69E-7898-4CF8-B447-EFF646FE3B44
Myrmecia banksi
sp.n.
(
Figs 4–6
)
Myrmecia banksi
is known only from low elevations along a narrow coastal and sub-coastal strip in NSW south from Sydney to Batemans Bay.
This species was referred to in previous JACP publications as the "greenhead" form of
M.
(
pilosula
), as “
M.
(
pilosula
) 2n=10”, or informally as “
M. banksi
”
.
Type
locality.
NEW
SOUTH
WALES
: South Nowra, shortly north of the junction of Forest Road and Bulldog Avenue track (-34 56, 150 37), ca 800 meters west of the Forest Road/Princes Highway intersection. Forest Road marks the boundary between Currambene State Forest (to the North) and Nowra State Forest. The area is referred to locally as Comberton,
Type
deposition.
Holotype
and
paratypes
in
ANIC
,
paratypes
or type-compared vouchers in
AMSA
,
MVMA
,
QMBA
,
SAMA
,
WAMA
,
TMHA
) and in
BMNH
,
CASC
,
MCZC
,
MHNG
.
Material examined, distribution.
Known from coastal or sub-coastal
NSW
, from Leumeah, Sydney, south to
Catalina, Batemans Bay. All
collections are from elevations below 70 meters. Localities most distant from the coast are at Wandandian (ca
5km
inland) and Leumeah (ca
24 km
).
Myrmecia banksi
will almost certainly range further north and south, and could occur more widely in the Sydney area where records of Jack-jumpers are currently sparse.
JACP
and
AAVAS
records.
NEW
SOUTH
WALES
: Leumeah, E of railway station [-34 0 3, 150 50], HI–
AAGR
13,
AAGT
11; Nowra [-34 53, 150 36], HI87–122–127, 91–057; South Nowra [-34 55, 150 36], HI99–013;
AAVAS
accessions 145, 147, 148, SB&SM; Wandandian [-35 5, 150 31], HI89–034, HI91–048, 100, 101; West of Nelligen [-35 39, 150 8], HI85–213, HI91–191; Sheep Station Creek near Nelligen [-35 39, 150 8], HI87–158; Batemans Bay [-35 42, 150 11], HI87–160; Catalina [-35 43, 150 11],
AAVAS
. The
JACP
“Nowra” samples were collected near
HMAS
Albatross
Naval Air Station; the “South Nowra” records from the vicinity of the
type
locality; and the Batemans Bay sample from near the western end of Maloneys Beach.
Worker diagnosis.
General features as illustrated and in key couplets 1, & 3 above.
Myrmecia banksi
is distinguished within the
pilosula
complex by its dense, brassy-green cephalic pubescence. This produces strong greenish-yellow reflections, readily visible in living specimens with hand lens magnification, and encouraged Imai’s field epithet “greenhead”. Anterior femora chocolate brown, each with a reddish-orange apical section up to 1/3 its length, matching the adjacent tibia. Middle tarsi and tibiae reddish-orange, matching those of fore legs.
Hind
femora and tibiae dark brown, like anterior femora; the tibiae sometimes a little lighter, with their apices and the tarsi progressively lighter in color towards the foot.
Myrmecia banksi
is otherwise morphologically similar to the eastern species
Myrmecia impaternata
and the Western Australian
M. imaii
, which have similar but usually muchless dense brassy cephalic pilosity, and distinctive, very different karyology (see below). The provenance of specimens and their comparison with confidently identified vouchers is important in differentiating these taxa.
FIGURES 4–6.
Myrmecia banksi
, Holotype, South Nowra, NSW. Standard views. HW 2.66 mm, WL 3.86 mm, PW 1.72 mm.
Dimensions.
(
Holotype
, smallest
paratype
, largest
paratype
(mm): TL = 13.04, 11.81, 13.45; HW = 2.66, 2.26, 2.76; HL = 2.44, 2.48, 2.77; CI = 109, 109, 111; EL =1.02, 0.87, 1.06; OI = 38, 38, 38; SL = 1.98, 1.75, 2.09; SI = 74, 77, 76; PW = 1.72, 1.70, 1.77; WL = 3.86, 3.33, 3.92; PetW = 0.94, 0.77, 1.01; PpetW = 1.50, 1.19, 1.60.
Etymology.
Named for Joseph Banks (
1743–1820
) who with Daniel Solander in 1770 first scientifically collected Australian ants and other insects at Botany Bay, NSW, while exploring ashore from James Cook’s HM Bark
Endeavour
in habitat similar to that at the
M. banksi
Type
Locality. The
Endeavour
landing site is about
100km
NNE of the
M. banksi
South Nowra site.
Karyology.
Most examined specimens (sampled from all above localities except Catalina and Batemans Bay) had the monomorphic karyotype 2K=6M +2M c +2A (2n=10) (
Imai, Taylor
et al.,
1994
: 147,
Fig. 5
h). One putative mutant individual from Leumeah (sample HI–AAGH–11) had a complicated translocation producing 2n=9 (
Imai, Crozier
et al.,
1977
).
Notes.
S
ympatric associations with other
M. pilosula
-complex species are unknown. Convincing karyological evidence identifies
M. banksi
(or a close ancestor) as one of the parent species of the apparently parthenogenetic and hybrid-originated
M. impaternata
(the other putative parental taxon is an element of the Eastern Race of
M. pilosula
: see below under
M. impaternata
). Because of close similarity between
M. banksi
and
M. impaternata
future studies, such as analysis of their distributional relationships between the NSW South Coast and Southern Tablelands, might require karyological or DNA analyses to authenticate identifications. A winged male is present in HI87–123.
Myrmecia pilosula
(Eastern Race) is considered likely to be found in future as a sympatric associate of
M. banksi
.
Research prospects.
See below under
M. impaternata
.