Rhophitulus labiosus, Ramos, Kelli S., 2014

Ramos, Kelli S., 2014, Three new bee species of Rhophitulus Ducke (Hymenoptera, Apidae, Protandrenini) from Argentina and Brazil, Zootaxa 3847 (4), pp. 545-556 : 546-548

Rhophitulus labiosus new species

( Figures 1–6 )

Diagnosis. Rhophitulus labiosus n. sp. and R. xenopalpus n. sp. are unique among other species of Rhophitulus in having modified labial palpi, which are characterized by enlarged and flattened palpus ( Figs. 3 , 25 ). Rhophitulus labiosus n. sp. differs from R. xenopalpus n. sp. by the following combination of features: larger body size; integument of body predominantly shiny, with very sparse and shallow punctures on mesoscutum ( Fig. 5 ); outer surface of hind basitarsus smooth and shiny; upper paraocular area weakly inflated; mandibles and labrum brown; vertex finely punctate; face, mesoscutum, and mesepisternum with sparse hairs ( Fig. 1–2 ); pronotal lobe light brown ( Fig. 2 ); compound eyes with sparse thin hairs. This species is only known from females.

Description. Holotype female. Approximate body length: 5.6 mm; maximum head width: 1.5 mm; maximum mesoscutum width: 1.2 mm; forewing length: 3.9 mm; maximum width of T2: 1.4 mm. Coloration. Integument predominantly dark brown, except for yellow spot on basal portion of fore- and midtibiae ( Figs. 1–6 ). Proboscis, mandible, labrum, underside of antennal flagellum, pronotal lobe, wing veins, tibial spurs, and tarsus light brown; tegula translucent light brown. Pubescence. Predominantly pale yellow and finely branched; prepygidial and pygidial fimbria pale brown; pronotal collar, metapostnotum, propodeum, and tibial scopae with white hairs; foretarsus with yellowish hairs. Labrum with dense and simple hairs; compound eyes with minute hairs; face and scape with sparse and semidecumbent hairs, on frons 0.3x as long as ocellar diameter (gradually increasing in length towards clypeus and lower paraocular area) ( Fig. 1 ); vertex with sparse and thin pilosity, except for few long hairs behind ocelli; gena with dense semidecumbent plumose hairs; ventral portion of gena with sparse, erect, finely branched hairs. Pronotal collar and edge of pronotal lobe with dense, short, plumose hairs, some long and finely branched hairs intermixed ( Fig. 2 ); upper portion of mesepisternum with dense, short, plumose hairs; lower half of mesepisternum with erect and long hairs, gradually increasing in length ventrally; ventral portion of mesepisternum without curved hairs apically; metepisternum with sparse minute hairs; mesoscutum and scutellum with sparse, erect, long hairs (ca. 1.0x as long as ocellar diameter) ( Fig. 5 ); metanotum with dense, erect, long, branched hairs (1.2x as long as ocellar diameter); metapostnotum with dense plumose and semidecumbent hairs, middle area glabrous ( Fig. 5 ); propodeum with very short and decumbent hairs (length about twice puncture diameter), except lateral corners with dense and long plumose hairs; tibial scopae with long, sparse, simple hairs (those on anterior surface about twice as long as maximum width of tibia); outer surface of hind basitarsus with spars, short, finely branched hairs ( Fig. 2 ); keirotrichia on inner surface of hind tibia and basitarsus with dense, uniform, short hairs. Disc of metasomal terga with tiny hairs (except by few long and erect hairs on lateral portion), becoming denser and longer towards the apex of metasoma ( Fig. 6 ); premarginal line of T2–T4 with loose fringe of hairs ( Fig. 6 ); marginal zone of T3 with sparse hairs; T4 with branched and denser pilosity than T3 ( Fig. 6 ); disc of S1–S3 with sparse, erect, plumose hairs; marginal zone of S1–S3 glabrous; distal half of S5 with dense, semidecumbent, plumose pilosity. Integumental surface. Predominantly smooth and shiny between punctures, with sparse and shallow punctures ( Figs. 1–2 ). Ventral portion of mesepisternum, metepisternum, propodeum, marginal zone of metasomal terga, and metasomal sterna reticulated between punctures. Labral plate smooth; facial fovea deep and smooth; upper portion of face densely punctate (≤1 pd), becoming sparser on lower portion (>4 pd on lower paraocular area) ( Fig. 1 ); clypeus coarsely punctate (about 2 pd); vertex sparsely and finely (>3 pd), space between punctures micropunctate; gena finely punctate (≤2 pd). Mesoscutum and scutellum with sparse punctures (>4 pd), micropunctate between piligerous punctures ( Fig. 5 ); metanotum with deeper and denser punctures than mesoscutum (≤1 pd) ( Fig. 5 ); metapostnotum reticulate, slightly depressed in comparison to propodeum, densely punctate on lateral portions (≤1 pd), and smooth at middle ( Fig. 5 ); upper portion of mesepisternum with dense and fine punctation; ventral portion of mesepisternum with coarse and sparse punctures; outer surface of hind basitarsus smooth and shiny. Disc of T1 and T2 closely punctate (<1 pd), diameter of punctures gradually decreasing towards metasomal apex ( Fig. 6 ); disc of T5 reticulated, with coarse and sparse punctures (≤1.5 pd); premarginal area smooth; marginal zone of metasomal terga reticulate; metasomal sterna reticulate between punctures (≤1.5 pd); surface of pygidial plate with microsculpture (this structure is difficult to describe further as the plate is almost entirely obscured by the preceding terga). Structure (measurements in mm). Head approximately 1.1x wider than long (1.51:1.34); labial palpi flattened and enlarged; first labial palpus longer than subsequent palpi ( Fig. 3 ); labral plate 1.4x wider than long (0.3:0.22), distal margin straight; basal portion of labral plate with two inflated areas; tentorial pit on epistomal suture, just below intersection with outer subantennal suture; compound eyes 1.8x longer than wide (0.94:0.51), inner orbits slightly convergent below (upper distance: 1.0, lower distance: 0.91); clypeus 1.6x broader than long (0.71:0.43) ( Fig. 1 ); frontal line shallow; upper paraocular area slightly inflated; facial fovea 2.4x longer than wide (0.31:0.13); gena narrow in lateral view, 0.6x as wide as eye width; forewing with two submarginal cells, first submarginal cell longer than second ( Fig. 4 ); 1m-cu reaching second submarginal cell at basal one-third; ventral margin of mid femur rounded, without acute projection; mid tibial spurs finely serrate, 0.4x as long as basitarsus (0.26:0.6); hind tibial spurs similar in length; marginal zone of metasomal terga slightly depressed in comparison to discs; tergal discs flat ( Fig. 6 ); T1 with lateral line; lateral fovea of T2 large and slightly depressed; pygidial plate V-shaped.

Male. Unknown.

Distribution. BRAZIL: Minas Gerais. This species was collected in Caatinga vegetation (Gabriel Melo, pers. comm.).

Type material. Holotype female ( DZUP), "Local Janaúba, MG\ Data 10/01/86 \ Col. G. Melo". Paratype, Brazil, Minas Gerais: 1 female ( DZUP), "Janaúba MG\ 4/1/1986 \ G. Melo".

Etymology. The epithet derives from the Latin word labiosus meaning "large lips", in reference to the peculiar morphology of the labial palpi.

Figures

FIGURES 1 – 6. Holotype female of Rhophitulus labiosus n. sp.: 1, head in frontal view. 2, lateral habitus. 3, detail of the unique labial palpus. 4, fore- and hind wings. 5, mesosoma in dorsal view. 6, metasoma in dorsal view.

FIGURES 19 – 27. Rhophitulus xenopalpus n. sp.: 19, female (holotype), head in frontal view. 20, female (holotype), lateral view. 21, female (holotype), mesosoma in dorsal view. 22, male, head in frontal view. 23, male, lateral view. 24, male, mesosoma in dorsal view. 25, female, detail of the unique labial palpus. 26, female, detail of labral plate. 27, female, metasoma in dorsal view.