Brachymelecta Linsley, 1939, previously the rarest North American bee genus, was described from an aberrant specimen and is the senior synonym for Xeromelecta Linsley, 1939
Author
Onuferko, Thomas M.
6E4CC25A-AD82-42D3-9846-C659EDEAF541
thomas.onuferko@gmail.com
Author
Packer, Laurence
06E03CC1-20DE-4968-8637-772B09832079
Department of Biology, York University, 4700 Keele St.
xeromelissa@gmail.com
Author
Genaro, Julio A.
A8ED1AB5-A208-4CD3-BE2C-0EAD8B19AA2B
Florida State Collection of Arthropods, 1911 SW 34 St.
polimita@hotmail.com
text
European Journal of Taxonomy
2021
2021-06-15
754
1
51
http://dx.doi.org/10.5852/ejt.2021.754.1393
journal article
6066
10.5852/ejt.2021.754.1393
bbecfe17-0d11-474f-9637-19918ef2716d
2118-9773
4965956
22C1F6A8-1FA5-482B-B577-9265D8C51183
Brachymelecta tibialis
(
Fabricius, 1793
)
Figs 4A
,
9B
,
16–17
Nomada tibialis
Fabricius, 1793: 346
(
♂
).
Crocisa pantalon
Dewitz, 1881: 198
(
♂
), pl. 5, fig. 2.
Proposed common name
Puerto Rican digger-cuckoo bee.
Diagnosis
The following morphological features in combination can be used to tell
B. tibialis
apart from all other
Brachymelecta
except
B. haitensis
, a Hispaniolan species: the mesoscutum and mesoscutellum both have well-defined bands of pale hairs along the entire midline that connect and thus give the appearance of a single band (
Fig. 16B, D
); the mesoscutellum sometimes also has pale hairs laterally but the pubescence is otherwise dark brown or black, sparse, and does not obscure the underlying integument (
Fig. 16D
); and each mesotibia of the female dorsally has a large glabrous area between a submedial band of offwhite hairs (nearer the base than apex) and a band on the apical margin (
Fig. 16A
).
Brachymelecta tibialis
may be separated from
B. haitensis
as follows. Whereas in
B. haitensis
the T1–T3 apical fasciae are complete (in males) or only narrowly interrupted medially (in females) and the lighter hairs covering the head, mesosoma, and metasoma are pale yellow, in
B. tibialis
the T1–T3 apical fasciae are narrowly interrupted medially (in males) or widely interrupted medially (in females) and the lighter hairs covering the head, mesosoma, and metasoma are off-white.
Brachymelecta tibialis
is the easternmost species in its genus and the only one known to occur in
Puerto Rico
and the
U.S. Virgin Islands
.
Material examined
Primary
type
material
COUNTRY UNKNOWN •
♂
,
N. tibialis
holotype;
Sehested
leg.;
NHMD
ZMUC 00241576
.
PUERTO RICO
•
♂
,
C. pantalon
holotype (studied from images: http://coll.mfn-berlin.de/u/c2e879);
Krug
leg.; ZMB 22477 for specimen, 22592 for dissected mouthparts
.
DNA barcoded material
Unavailable.
Fig. 16.
Brachymelecta tibialis
(
Fabricius, 1793
)
. A–B, D. Female (INHS 427051).
A
. Habitus, lateral view.
B
. Habitus, dorsal view.
C
. Male (UPRM), habitus, lateral view.
D
. Axillae and mesoscutellum, dorsal view.
Non-barcoded material
COUNTRY UNKNOWN •
1 ♂
; “
American Isles
”;
Beck
leg.;
NHMD
.
PUERTO RICO
•
1 ♀
;
Aguada
,
Cerro Gordo
;
23 Aug. 1987
;
Douglas II
leg.;
UPRM
•
1 ♂
;
Lares
,
Lares
;
3 Nov. 1922
;
F. Sein
leg.;
UPRM
Acc.
416-1922
•
1 ♂
;
Orocovis
,
Orocovis
;
3 Oct. 1979
;
A.E.Q.
leg.;
UPRM
•
1 ♀
;
Utuado
,
Utuado
;
Jul. 1941
;
G. Lamboglia
leg.;
INHS
427051
.
UNITED STATES VIRGIN ISLANDS
•
1 ♂
;
St. Croix
;
Eggers
leg.;
NHMD
.
Redescription
Male
MEASUREMENTS. Length
9.4 mm
; ITW
2.6 mm
; head length
2.7 mm
; head width 3.0 mm; fore wing length
8.7 mm
.
INTEGUMENT COLORATION. Dark brown to black except as follows. Mandible with apical third golden yellow. Mandible with middle third, labrum, mesoscutellum, metanotum, and legs, excluding dark brown to black coxae and tibial spurs, reddish orange (reddish brown in some non-type specimens). Tegula amber. Fore wing dusky subhyaline throughout except along posterior margin and around third submarginal crossvein and second recurrent vein, where hyaline. Hind wing dusky subhyaline to hyaline. Much of metasoma with reddish tinge.
PUBESCENCE. Face with hairs densest around antennal socket, predominantly off-white/pale yellow but dark brown/gray above antennal socket and in lower paraocular area. Clypeus with upper half densely hairy; lower half nearly bare. Upper paraocular and frontal areas and vertexal area (except along preoccipital ridge and margin of compound eye) mostly exposed. Head with dense, erect hairs along preoccipital ridge off-white except for medial dark brown/gray patch behind ocelli. Genal beard hairs predominantly dark brown/gray. Mesoscutum sparsely hairy except densely hairy anteriorly and along margins, with hairs short, appressed, and predominantly dark brown/gray except for small patch of offwhite hairs on each side along anterior margin between midline and pronotal lobe, pair of central spots of off-white hairs, small patch of off-white hairs in front of axilla, well-defined band of off-white hairs along midline, and off-white hairs along margins.Axilla with conspicuous patch of black hairs. Mesoscutellum with well-defined band of off-white hairs along midline, seemingly continuous with band of pale hairs along midline of mesoscutum, and small patch of off-white hairs laterally but with pubescence otherwise dark brown or black and sparse, not obscuring underlying integument. Metanotum with short, appressed dark brown hairs. Propodeum with erect, predominantly off-white hairs. Mesopleuron sparsely hairy, but with (off-white) hairs moderately dense ventrally as well as between two sparsely hairy circular patches (one beneath base of fore wing around somewhat densely hairy hypoepimeral area, a larger one occupying much of ventrolateral half of mesopleuron). Legs, from coxae to tarsi, with appressed and erect off-white hairs, ventrally with golden-yellow hairs. Profemur with posteroventral fringe of dense, off-white hairs. Protibia with two bands or spots of short, appressed off-white hairs, one in basal half and one on apical margin. Mesotibia with patch of very dense short, appressed off-white hairs, occupying nearly entire dorsal surface. Metatibia with patch of sparser off-white hairs in apical two-thirds. T1–T3 with well-defined, medially interrupted apical fasciae, each with lobe-like anterolateral extension on each side with erect among appressed off-white hairs (that of T2 with pair of anterolateral extensions on each side in
C. pantalon
holotype
and some non-type specimens). T3 with fascia laterally removed from apical margin, narrowed or interrupted mesad each anterolateral extension. T4–T6 without fasciae, although T4 with few sparsely scattered pale hairs present on apical impressed area in some non-type specimens. Exposed metasomal sterna mainly with short, appressed off-white hairs.
SURFACE SCULPTURE. Labrum and clypeus with punctures equally dense (most i≤1d). Small impunctate shiny spot lateral to lateral ocellus. Mesoscutum and mesoscutellum with fine punctures, not much coarser than those of metasomal terga. Mesoscutum and mesoscutellum with punctures equally dense (most i<1d) and similar in size. Mesopleuron with denser (most i<1d) punctures in upper half than ventrolateral half (many i=1–2d), interspaces well-defined and somewhat dull due to tessellate surface microsculpture. Discs of metasomal terga with punctures very fine, dense (i≈1d), interspaces dull due to tessellate surface microsculpture.
STRUCTURE. Mandible tridentate, with small inner tooth approximately ⅓ length of mandible from base and slightly larger inner tooth approximately ⅓ length of mandible from apex as well as usual large apical tooth (rutellum) (difficult to see in
N. tibialis
holotype
because mandibles closed; described from
C. pantalon
holotype
and non-type specimens). Maxillary palpus with one palpomere (mouthparts not extended in
N. tibialis
holotype
; described from two non-type specimens). Scape with greatest length 1.8 × greatest width. F2 nearly as long as wide (L/W ratio = 0.9). Mesoscutellum strongly bigibbous, with pair of long, acute, subparallel spines, directed posteriorly. Lateral surface of propodeum posterior to spiracle with rugose crescent ridge, strongly carinate above and joining anterior lip of spiracle. Fore wing with three submarginal cells. T7 with slight median emargination.
Female
Description as for male except for usual secondary sexual characters and as follows: scape longer, with greatest length 2.2 × greatest width; mesotibia dorsally with large glabrous area between submedial band of off-white hairs (nearer the base than apex) and band on apical margin; T1–T3 with fasciae more widely interrupted medially; T6 with narrow, V-shaped but apically rounded pygidial plate.
Distribution
Previously known only from
Puerto Rico
and herein newly reported from St. Croix, this is the only species of
Brachymelecta
known to occur on either of the two islands (
Fig. 4A
).
Ecology
Host records
Unknown. Given that New World
Melectini
have been associated only with anthophorine bees (mostly
Anthophora
), presumably
B. tibialis
is a cleptoparasite of
A. tricolor
, the only species in its genus known to occur in
Puerto Rico
and also the only one represented in the
U.S. Virgin Islands
(
Brooks 1999
).
Floral records
Unknown.
Remarks
Linsley (1943)
described the female of
Crocisa pantalon
(as
Melecta
(
Melectomorpha
)
pentalon
[
sic
]) based on a specimen from
Lares
,
Puerto Rico
(UPRM Acc. 416-1922), which
Genaro & Franz (2008)
determined was actually a male. Although a female specimen was known to
Genaro & Franz (2008)
, the female of
B. tibialis
is described here for the first time. Donald B. Baker correctly recognized the
holotype
of
Nomada tibialis
as belonging to the same species as “
Nesomelecta pantalon
” (in 1980), and the synonymy was established in
Michener (2000)
through a personal communication.
Moure
et al.
(2007)
erroneously list the USNM and
Genaro & Franz (2008)
the NHMD (as ZMUC) as the repository for the
holotype
of
C. pantalon
. The specimen is actually deposited in the ZMB.