Centris (Anisoctenodes), Vivallo, 2020

Vivallo, Felipe, 2020, The species of the bee genus Centris of the “ hyptidis group ” revisited with the description of Centris (Anisoctenodes) new subgenus (Hymenoptera: Apidae: Centridini), European Journal of Taxonomy 709, pp. 1-17 : 4-13

Anisoctenodes subgen. nov.

urn:lsid:zoobank.org:act:9CAFCE9C-F599-465F-91EC-7CD447E19D44

Type species

Centris hyptidis Ducke, 1908 .

The species of this new subgenus can be recognized by the shape of the trochanter of fore and middle legs with a basal laminar projection ( Fig. 2 A–D), and by the fore elaiospathes of the females ( Fig. 3 A–D) with extremely small posterior giant setae. This rudimentary secondary comb apparently is not used for oil collection, judging by their vestigial condition.

Etymology

From Greek ‘ anisos ’ (‘unequal’) and ‘ ctenodes ’ (‘comb-like’) based on the particular shape of the fore elaiospathe of the females. The morphology of the oil-collecting apparatuses of the species of this group is unique in Centris which contrasts with the pattern found in the rest of the species of the genus. The shape considered ancestral includes an anterior primary comb formed by a single row of enlarged, flattened and apically curved overlapping setae, and a secondary comb formed by four giant spatulate setae located in opposition to the primary comb ( Neff & Simpson 1981).

Species included

Centris anisitsi , C. hyptidis , C. hyptidoides and C. thelyopsis .

Remarks

Most species of Anisoctenodes subgen. nov. exhibit interesting associations with oil-offering flowers, mainly with Angelonia (Plantaginaceae) . The species of this genus have trichomatic elaiophores, which require specialized structures for their exploitation ( Vogel 1974; Neff & Simpson 1981). The females have long and branched hairs of spatulate apex ( Vogel & Machado 1991: fig. 9C, G and Martins et al. 2013: fig. 9C–E). These bristles are used for oil collection not through scraping by the elaiophores as in other species of Centris , but by absorption, using capillarity forces ( Vogel & Machado 1991). A detailed description of the oil-collecting apparatus and the collecting behavior of C. hyptidis can be found in Machado et al. (2002) and in Martins et al. (2013) for C. hyptidoides .

Distribution

The species of Anisoctenodes subgen. nov. occur in the South American diagonal of open dry areas formed by the Caatinga, Cerrado, Chacoan and Pampean Provinces. These provinces belong to the Chacoan subregion of the Neotropics ( Morrone 2014). Centris hyptidis is distributed mainly in the Caatinga, with peripheral records in the north of the Paraná Forest Province and in the Cerrado. In this latter province also occurs C. thelyopsis in the dry forests of the upper Tocantins River ( Vivallo & Melo 2009). Centris anisitsi and C. hyptidoides are distributed in the Chacoan Province, with the latter species also being registered – for the moment by a single record – in the Paraná Forest Province ( Fig. 7 ).

The description of the morphology of Centris hyptidis , C. hyptidoides and C. thelyopsis , along with their distribution ranges and floral hosts, can be found in Vivallo & Melo (2009). The redescription of C. anisitsi and the description of the female are provided below.

Key to the species of Centris (Anisoctenodes) subgen. nov.

Modified from Vivallo & Melo (2009).

1. Head without yellow areas ( Fig. 1A, C ). Clypeus with coarse and very dense punctation, with conspicuous median longitudinal carina ( Fig. 1A ). Lateral surface of mesepisternum with brown pubescence ( Fig. 1B, D ). Male with fore and middle legs with brown pubescence ( Fig. 1D ) ........... ........................................................................................................ Centris anisitsi ( Schrottky, 1908)

– Head with yellow areas ( Figs 4A, C , 5A, C , 6A, C ). Clypeus with relatively fine and not extremely dense punctation, without conspicuous median longitudinal carina. Lateral surface of mesepisternum with yellowish pubescence ( Figs 4B, D , 5B, D , 6B, D ). Male with fore and middle legs with yellowish pubescence, at least in part ( Figs 4 C–D, 5C–D, 6C–D) ................................................................... 2

2. Metasoma with bands of orange pilosity ( Fig. 6B, D ). Hind leg with yellowish pubescence ( Fig. 6B, D ). Clypeus of male yellow with a large triangular black spot in the middle ( Fig. 6C ) ............................................................................. Centris thelyopsis Vivallo & Melo, 2009

– Metasoma with predominantly black pubescence (except T1, with yellow pilosity and the last two terga with white pilosity) ( Figs 4B, D , 5B, D ). Hind leg with predominantly black pubescence ( Figs 4B, D , 5B, D ). Male with clypeus entirely yellow ( Figs 4C , 5C ) ........................................... 3

3 ♀: fore elaiospathe with four secondary posterior giant setae beside the primary anterior comb. T4 with yellowish pilosity at least on distal margin ( Fig. 5B ). ♂: T1 with uninterrupted band of yellowish pilosity. F1 3.2× as long as F2. Apical margin of T4 with a complete narrow band of plumose hairs ........................................................................ Centris hyptidoides Roig-Alsina, 2000

– ♀: fore elaiospathe without secondary posterior giant setae beside the primary anterior comb. T4 with predominantly black pilosity sometimes with some yellow hairs intermixed ( Fig. 4B ). ♂: T1 with band of yellowish pilosity generally interrupted in the middle. F1 2.9× as long as F2. Apical margin of T4 with narrow band of plumose hairs restricted to lateral portions of tergum .................................................................................................. Centris hyptidis Ducke, 1908

Figures

Fig. 2. Trochanter of female fore leg (ZMB †). A. Centris anisitsi (Schrottky, 1908), Paraguay, San Bernardino (LPBC †). B. C. hyptidis Ducke, 1908, Brazil, Vitória da Conquista (MNRJ †). C. C. hyptidoides Roig-Alsina, 2000, Paraguay, San Pedro Cororo (MNRJ †). D. C. thelyopsis Vivallo & Melo, 2009, Brazil, Teresina de Goiás (DZUP †). Scale bars: 0.2 mm.

Fig. 3. Elaiospathe of female fore leg. A. Centris anisitsi (Schrottky, 1908), Paraguay, San Bernardino (ZMB †). B. C. hyptidis Ducke, 1908, Brazil, Vitória da Conquista (MNRJ †). C.C. hyptidoides Roig- Alsina, 2000, Paraguay, San Pedro Cororo (LPBC †). D. C. thelyopsis Vivallo & Melo, 2009, Brazil, Teresina de Goiás (DZUP †). Scale bars: 0.2 mm.

Fig. 7. Distribution map of the species of Centris (Anisoctenodes) subgen. nov.

Fig. 1. Centris anisitsi (Schrottky, 1908). A–B. ♀, Paraguay, San Bernardino (ZMB †). C–D. ♂, Paraguay, Asunción, holotype (ZMB). A, C. Frontal view. B, D. Habitus, lateral view. Scale bars: 1 mm.

Fig. 4. Centris hyptidis Ducke, 1908. A–B. ♀, Brazil, Vitória da Conquista (MNRJ †). C–D.♂, Brazil, Vitória da Conquista (MNRJ †). A, C. Frontal view. B, D. Habitus, lateral view. Scale bars: 1 mm.

Fig. 5. Centris hyptidoides Roig-Alsina, 2000. A–B. ♀, Paraguay, San Pedro Cororo (LPBC †). C–D. ♂, Paraguay, San Pedro Cororo (LPBC †). A, C. Frontal view. B, D. Habitus, lateral view. Scale bars: 1 mm.

Fig. 6. Centris thelyopsis Vivallo & Melo, 2009, paratypes. A–B. ♀, Brazil, Teresina de Goiás (DZUP †). C–D. ♂, Brazil, Teresina de Goiás (DZUP †). A, C. Frontal view. B, D. Habitus, lateral view. Scale bars: 1 mm.