Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini)
Author
Gibbs, Jason
text
Zootaxa
2011
2011-10-28
3073
1
216
journal article
31531
10.5281/zenodo.1049595
1a985cc7-af57-45e9-a988-c3beda3c15b4
1175-5326
1049595
B5AF6DF4-D3A7-4942-A94F-CC051D8074CF
Lasioglossum
(
Dialictus
)
flaveriae
(Mitchell)
(
Figures 98–101
)
Dialictus flaveriae
Mitchell, 1960
: 393
. Ƥ 3.
Holotype
.
Ƥ
USA
, Florida, Dade Co., Everglades Nat. Pk.,
10.iii.1955
on
Flaveria linearis
(H.A.
Denmark
)
; [
FSCA
]. Examined.
Dialictus tahitensis
Mitchell, 1960
: 421
. Ƥ.
[new synonymy]
Holotype
. Ƥ
USA
, Florida, Dade Co., Tahiti Beach,
29.v.1927
(S. Graenicher); [
NCSU
]. Examined.
FIGURE 98
.
Lasioglossum flaveriae
(Mitchell)
female, (A) lateral habitus, (B) face. Scale bars = 1 mm.
FIGURE 99
.
Lasioglossum flaveriae
(Mitchell)
female, dorsal view of mesosoma.
FIGURE 100
.
Lasioglossum flaveriae
(Mitchell)
male, (A) lateral habitus, (B) face. Scale bars = 1 mm.
Taxonomy.
Krombein, 1967
:
Lasioglossum
(
Dialictus
)
flaveriae
, p. 463,
L
. (
D
)
tahitense
, p. 466 (catalogue);
Moure and Hurd, 1987
:
Dialictus flaveriae
, p. 100,
D
.
tahitensis
, p. 132 (catalogue).
Diagnosis.
Both sexes of
L
.
flaveriae
can be recognised by the following diagnostic combination: metapostnotum smooth, rugae not extending more than halfway to posterior margin (
Figs. 99
,
101
); mesepisternal punctures deep and distinct; gena narrower than eye; and lower paraocular area with sparse tomentum. Males can also be recognized by the elongate S5–S6 hairs visible as two posteriorly directed tufts in dorsal view. They are most similar to the Caribbean species
L
.
gundlachii
(
Baker
)
which has the surface of the mesoscutum and mesepisternum duller due to microsculpture.
Redescription.
FEMALE. Length
4.11–4.66 mm
; head length
1.16–1.25 mm
; head width
1.18–1.32 mm
; forewing length
2.78–3.27 mm
.
Colouration
. Head and mesosoma pale green to blue. Clypeus with apical half blackish brown. Antenna dark brown, flagellum with ventral surface brownish yellow. Tegula reddish brown. Wing membrane subhyaline, venation and pterostigma yellowish brown. Legs brown except tarsi, and apical and basal portions of tibiae brownish yellow. Metasoma reddish brown, terga and sterna with apical margins translucent brownish yellow.
Pubescence
. Dull white. Moderately sparse. Head and mesosoma with moderately sparse woolly hairs (1–2 OD), longest on genal beard, metanotum, and mesopleuron (2–2.5 OD). Paraocular area and gena with sparse subappressed tomentum. Propodeum with moderately dense plumose hairs on lateral and posterior surfaces (2–2.5 OD). Metasomal terga with moderately sparse, fine hairs. T1 acarinarial fan limited to small lateral area, dorsal opening wider than lateral patches. T1–T6 without tomentum. T2 apicolateral and T3–T4 apical margins with sparse apical fringes.
Surface sculpture
. Face imbricate, punctation very fine. Clypeus with apical half polished, punctation moderately sparse apically (i=1–2d), denser basally (i≤d). Supraclypeal area with punctation moderately sparse (i=1–2d), denser laterally. Lower paraocular area punctation dense (i≤d). Antennocular area punctation moderately dense (i=1–1.5d). Upper paraocular area and frons very finely punctate. Ocellocular area punctate (i=1–1.5d). Gena lineolate. Postgena imbricate. Mesoscutum weakly imbricate, polished submedially, punctation moderately sparse between parapsidal lines (i=1–2.5d), dense laterad of parapsidal line (i≤d), contiguous on anterolateral portion. Mesoscutellum similar to mesoscutum, submedial punctation sparse (i=1.5–3d). Axilla minutely punctate. Metanotum imbricate. Preëpisternum rugulose. Hypoepimeral area imbricate-punctate (i=1–1.5d). Mesepisternum weakly imbricate, distinctly punctate (i=1–2d). Metepisternum with upper half carinulate and ventral portion imbricate. Metapostnotum with short rugae not extending halfway to posterior margin, posterior margin weakly imbricate. Propodeum with dorsolateral slope imbricate, lateral and posterior surfaces tessellate-imbricate. Metasomal terga polished, punctation moderately sparse basally (i=1–2d), more widely spaced apically (i=1–2.5d), T2 apical impressed area impunctate.
Structure
. Head moderately wide (length/width ratio = 0.95–0.99). Eyes convergent below (UOD/LOD ratio = 1.27– 1.30). Clypeus 1/2–2/3 below suborbital tangent, apicolateral angle convergent. Antennal sockets close (IAD/OAD <0.5). Frontal line carinate, ending 2–2.5 OD below median ocellus. Gena narrower than eye. Inner metatibial spur pectinate with 3–4 branches. Metapostnotum moderately elongate (MMR ratio = 1.10–1.20), posterior margin rounded onto posterior surface. Propodeum with oblique carina absent, lateral carina not reaching dorsal margin.
MALE. Similar to female except for the usual secondary sexual characters and as follows. Length
3.63–3.93 mm
; head length
1.25–1.28 mm
; head width
1.22–1.26 mm
; forewing length
3.15–3.21 mm
.
Colouration
. Flagellum with ventral surface reddish brown. Legs brown, except tibial bases and apices, and tarsi brownish yellow, pro- and mesotibiae sometimes infused with brownish yellow.
Pubescence
. S2–S4 apical halves with moderately dense hairs (1.5 OD), S5–S6 lateral portions with medially directed elongate hairs (3–4 OD).
Surface sculpture
. Punctation coarser. Metasomal terga with apical impressed areas impunctate.
Structure
. Head moderately elongate (length/width ratio = 1.02). Eyes strongly convergent below (UOD/LOD ratio = 1.45–1.48). Clypeus 2/3 below suborbital tangent, apicolateral margins convergent. Antennal sockets distant (IAD/OAD> 1.1). Frontal line carinate, ending 2 OD below median ocellus. Pedicel subequal to F1. F2 length 1.3–1.4X F1. F2–F10 short (length/width ratio = 1.15–1.30). Metapostnotum moderately elongate (MMR ratio = 1.20), posterior margin rounded onto posterior surface. Propodeum with oblique carina absent.
Terminalia
. Gonostylus posteriorly directed, very long setae emerging from base. Retrorse lobe short.
Range.
Bahamas
, Florida (
Fig. 102
).
Additional material examined.
BAHAMAS
: Gorda Cay, N26°05ʹ W77°32ʹ,
14–20.vi.1998
(S. Glasscock); [
UCFC
];
USA
: FLORIDA: 2ƤƤ Flamingo, Everglades N.P.,
1–5.xii.1961
(Munroe,
Holland
& Chillcott); [
CNC
]; 1Ƥ
paratype
Dade Co., Everglades Nat. Pk.,
10.iii.1955
(H.A.
Denmark
); 1Ƥ
paratype
Dade Co., Everglades Nat. Pk.,
11.iii.1955
(H.A.
Denmark
); 233
paratype
s Cape Sable, Everglades N.P.,
25.iii.1954
on salt flats (K.V. Krombein); 3ƤƤ
paratypes
Paradise Key,
6.iv.1951
(H. & M. Townes); [
CUIC
]; 1Ƥ Mahogany Hammock, Everglades N.P.,
4.xii.1970
(J. Powell); [
EMEC
];13
allotype
, Dade Co., Everglades Nat. Pk.,
17.iii.1955
on
Lyonia mariana
(H.A.
Denmark
)
; [
FSCA
]; 13
paratype
Cape Sable, Everglades N.P.,
25.iii.1954
on salt flats (K.V. Krombein); 4ƤƤ
paratypes
Dade Co., Everglades Nat. Pk.,
11.iii.1955
(H.A.
Denmark
); 1Ƥ
paratype
Matheson Hammock,
8.iv.1955
(T.B. Mitchell); 3ƤƤ
paratypes
Paradise Key,
6.iv.1951
(H. & M. Townes); [
NCSU
]; 1Ƥ
paratype
, Cape Sable, Everglades N.P.,
25.iii.1954
on salt flats (K.V. Krombein); 13
paratype
, Paradise Key, Everglades N.P.,
22.iii.1954
(K.V. Krombein); [
NMNH
]; 1Ƥ Lee Co.,
N26.4479
W082.0407
,
5.vi.2007
(S.W. Droege); 1Ƥ Lee Co.,
N26.4419
W082.0803
,
5.vi.2007
(S.W. Droege); 1Ƥ Martin Co.,
N27.0863
W080.1248
,
4.vi.2007
(S.W. Droege); [
PCYU
].
FIGURE 101
.
Lasioglossum flaveriae
(Mitchell)
male, dorsal view of mesosoma.
Floral records.
AMARANTHACEAE
:
Achyranthes
“mercantifolia”
;
ASTERACEAE
:
Flaveria linearis
,
Mikania
,
Sartwellia flaveriae
;
ERICACEAE
:
Lyonia mariana
.
DNA
Barcode.
Available. Multiple sequences.
Comments.
Uncommon.
The
holotype
specimens of
Dialictus flaveriae
and
D
.
tahitensis
differ only in size and colouration. Neither of these characters is reliable for delimiting
Dialictus
species and colour is often affected by preservation. Both
holotypes
have brownish orange metasomata but this might be an artefact.
Paratypes
and recently collected material have the metasoma reddish brown.
The West Indian species
L
.
gundlachii
is very similar to
L
.
flaveriae
both morphologically and based on DNA barcodes. Several Floridian species also occur in
Cuba
and islands of the West Indies (
e
.
g
.
L
.
eleutherense
discussed above and
L
.
halophitum
below). Jamaican specimens of
L
.
gundlachii
were found to have more microsculpture on the mesosoma than does
L
.
flaveriae
. These two species show affinities to mainland Neotropical species (see
Danforth
et al
. 2003
).