Brachymelecta alayoi ( Michener, 1988 )

Onuferko, Thomas M., Packer, Laurence & Genaro, Julio A., 2021, 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, European Journal of Taxonomy 754, pp. 1-51 : 10-13

Brachymelecta alayoi ( Michener, 1988)

Figs 3 , 4A , 17

Xeromelecta alayoi Michener, 1988: 377 (♀), figs 1–4.

Proposed common name

Alayo’s digger-cuckoo bee.

Diagnosis

Unique within the genus to B. alayoi are each of the following morphological features: the mesoscutum has a well-defined band of yellow hairs along the midline that does not attain its posterior margin ( Fig. 3B, D ); each mesotibia of the female has a patch of yellow hairs that occupies nearly its entire dorsal surface ( Fig. 3A ); and the mesoscutellum, except for the pair of spines and around their bases, is densely covered in yellow pubescence, such that the underlying integument is greatly obscured ( Fig. 3D ). Brachymelecta alayoi most closely resembles B. haitensis , a Hispaniolan species, but in B. haitensis the mesoscutum and mesoscutellum both have well-defined bands of pale yellow hairs along the entire midline that connect and thus give the appearance of a single band; the mesoscutellum sometimes also has pale yellow hairs laterally, but the pubescence is otherwise dark brown or black, sparse, and does not obscure the underlying integument; each mesotibia of the female dorsally has a large glabrous area between a submedial band of off-white to pale yellow hairs (nearer the base than apex) and a band on the apical margin; and the T1–T3 fasciae of the male are complete. Brachymelecta alayoi is the only species in the genus known to occur in Cuba, where it is endemic.

Material examined

Primary type material

CUBA • ♀, holotype (studied from images); Pinar del Río, Rancho Mundito , Sierra de los Órganos ; 4 Jul. 1947; F. de Zayas and V.J. Ferras leg.; KUNHM 1461055 .

DNA barcoded material

Unavailable.

Non-barcoded material

CUBA • 1 ♂; Artemisa, Pan de Guajaibón ; Jun. 1987; R. Alayo leg.; PCYU • 1 ♂; Artemisa, Soroa ; Aug. 1990; J.A. Genaro leg.; USNM • 1 ♀; Santiago de Cuba, La Gran Piedra , Sierra Maestra ; May 1955; P. Alayo leg.; JAG • 1 ♂; same collection data as for preceding; Jun. 2001; J.A. Genaro leg.; JAG .

Redescription

Female

MEASUREMENTS. Length 11.2 mm (11 mm for holotype; Michener 1988); ITW 2.7 mm; head length 2.7 mm; head width 3.3 mm; fore wing length 8.6 mm (9 mm for holotype; Michener 1988).

INTEGUMENT COLORATION. Dark brown to black except as follows. Mandible with apical third golden yellow in non-type specimen. Mandible with basal two-thirds, labrum, flagellum with ventral surface (in non-type specimen), tip of mesoscutellar spine, and legs, excluding dark brown coxae and tibial spurs, reddish orange. Tegula amber. Fore wing dusky subhyaline throughout, slightly darker beyond venation. Hind wing dusky subhyaline to hyaline. Much of metasoma with reddish tinge in non-type specimen.

PUBESCENCE. Face with hairs dense throughout except clypeus with lower quarter and area around ocelli mostly exposed, predominantly pale to golden yellow but dark brown/black around ocelli. Head with dense, erect hairs along preoccipital ridge almost entirely pale to golden yellow. Genal beard hairs predominantly pale to golden yellow. Mesoscutum sparsely hairy except densely hairy anteriorly and along margins, with hairs short, appressed, and predominantly dark brown/gray except for small patch of golden-yellow hairs on each side along anterior margin between midline and pronotal lobe, pair of central spots of golden-yellow hairs and narrow longitudinal band posterior to each extending to axilla, well-defined band of golden-yellow hairs along most of midline (not attaining posterior margin), and pale to golden-yellow hairs along margins. Axilla with conspicuous patch of black hairs. Mesoscutellum, except for pair of spines and around their bases, densely covered in golden-yellow pubescence greatly obscuring underlying integument. Metanotum with long, erect/suberect golden-yellow hairs, densest medially. Propodeum with erect, predominantly pale to golden-yellow hairs. Mesopleuron with (pale to golden-yellow) hairs moderately dense ventrally as well as between two sparsely hairy circular patches (one beneath base of fore wing (hypoepimeral area), a larger one occupying much of ventrolateral half of mesopleuron). Legs, from coxae to tarsi, with appressed and erect pale to golden-yellow hairs. Profemur with posteroventral fringe of dense, pale yellow hairs. Protibia covered in sparse to moderately dense pale to golden-yellow hairs. Mesotibia and metatibia each with patch of moderately dense short, appressed pale to golden-yellow hairs, occupying nearly entire dorsal surface (with sparsely hairy ovate patch in basal quarter). T1–T4 with well-defined medially interrupted apical fasciae, each with lobe-like anterolateral extension on each side with erect among appressed golden-yellow hairs except that of T2 with pair of anterolateral extensions on each side. T3 and T4 each with fascia laterally removed from apical margin, narrowed or interrupted mesad each anterolateral extension. T5 and T6 without fasciae. Exposed metasomal sterna mainly with short, appressed pale yellow hairs.

SURFACE SCULPTURE. Labrum and clypeus (except medially in lower quarter where sparsely punctate) with punctures equally dense (most i≤1d). Clypeus with many smaller punctures among large ones. Integument lateral to lateral ocellus punctate. 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 shining. 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 holotype because mandibles closed; described from nontype specimen). Maxillary palpus apparently with one palpomere (three according to Michener 1988) (mouthparts not extended in holotype; described from non-type specimen). Scape with greatest length 2.2 × 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 (difficult to see in holotype because integument obscured by dense pubescence; described from non-type specimen). Fore wing with two submarginal cells (second submarginal crossvein present but incomplete in both fore wings of all known specimens, including only paratype; Michener 1988). T6 with narrow, V-shaped but apically rounded pygidial plate with median longitudinal ridge.

Male

Description as for female except for usual secondary sexual characters and as follows: scape shorter, with greatest length 1.8 × greatest width; mesotibia with patch of very dense, short, appressed, pale to golden-yellow hairs, denser than hairs on mesotibia of female and metatibia of both sexes; T5 with

small patches of pale yellow hairs along anterior margin of apical impressed area; T7 with slight median emargination.

Distribution

This species is known only from Cuba and is the only species of Brachymelecta known to occur in the country ( Fig. 4A ).

Ecology

Host records

Unknown. Given that New World Melectini have been associated only with anthophorine bees (mostly Anthophora Latreille, 1803 spp. ) ( Hymenoptera : Apidae : Anthophorinae ), presumably B. alayoi is a cleptoparasite of one or both species of Anthophora — A. atrata Cresson, 1865 and A. hilaris Smith, 1879 — known to occur in Cuba (see Brooks 1999).

Floral records

Unknown.

Remarks

The male of B. alayoi is described here for the first time. The only (female) paratype (figs 2, 4 in Michener 1988) is meant to have been deposited in the USNM but does not appear to be there (S.G. Brady and E. Okonski, personal communication, 2019).

Figures

Fig. 3. Brachymelecta alayoi (Michener, 1988). A–B, D: female (JAG); C: male (JAG). A. Habitus, lateral view. B. Habitus, dorsal view. C. Habitus, lateral view. D. Axillae and mesoscutellum, dorsal view.

Fig. 4. Species distribution maps.A. Brachymelecta alayoi (Michener, 1988) (yellow circles),B. haitensis (Michener, 1948) (red circles), and B. tibialis (Fabricius, 1793) (blue circles). B. B. californica (Cresson, 1878) (red and blue circles indicate barcoded specimens assigned BINs BOLD:AAC6481 and BOLD:AAC6482, respectively). C. B. interrupta (Cresson, 1872). D. B. larreae (Cockerell, 1900). Known localities based on studied material and literature records are indicated by yellow circles except where indicated otherwise; subnational entities colored in orange indicate known/published provincial/ state records.

Fig. 17. Fully resolved single most parsimonious tree obtained through maximum parsimony analysis (in TNT) of a combined character set, consisting of 28 morphological characters and DNA barcodes (658 bp, of which 194 were parsimony-informative), with extended implied character weighting. Only morphological characters are shown, with black circles indicating nonhomoplasious changes (autapomorphies or synapomorphies) and empty circles indicating homoplasious changes. Numbers above the circles identify the different characters whereas the numbers below are the assigned character states (see Supp. file 2 for the corresponding descriptions). Numbers to the left of nodes are Bremer support values (above branches) and GC values (below branches).