Merobruchus santiagoi Ribeiro-Costa

Ribeiro-Costa, Cibele Stramare, 2007, A new species of Merobruchus Bridwell near Merobruchus boucheri Kingsolver (Coleoptera: Chrysomelidae: Bruchinae), Zootaxa 1449, pp. 51-56 : 52-56

Merobruchus santiagoi Ribeiro-Costa , new species

( Figs 1, 2, 4 , 5, 6 , 8, 10 , 12, 13 )

Body length 3.56 mm (3.40–4.04 mm, n = 10), width 2.00 mm (1.84–2.20 mm, n = 10); pronotum length 1.19 mm (1.08–1.28 mm, n = 10), width 1.43 mm (1.32–1.56 mm, n = 10); elytron lenght 2.13 mm (1.96–2.40 mm, n = 10), width 1.10 mm (1.00– 1.16 mm, n = 10).

Integument frequently dark red ( Figs 1, 2 ) with a median stripe on pronotum and elytra piceous; some specimens with many other areas piceous or entirely piceous. Anterior and middle legs light red, hind legs dark red. Antennae entirely light red.

Vestiture light yellow, gray and dark brown. Pronotum with a median stripe of dark brown pilosity with some intercalated yellow hairs, predominant in the lateral areas. Elytra with light yellow hairs with patches of dark brown hairs in the interstriae 3, 5, 7 and 9; the remainder of the interstriae with only light yellow pilosity, except the first and the scutellum with grayish pilosity ( Fig. 1 ). Pygidium with a basal median and triangular dense light yellow patch; two others patches elongated in the sublateral areas ( Fig. 4 ). Ventral region of body with grayish pilosity; lateral areas with light yellow hairs. Some specimens showed variation in tonality of pilosity in the pronotum and elytra, from light yellow to gray ( Fig. 2 ).

Head elongated, 1.3 times longer than wide, uniformly punctate; labrum with some punctures; frons convex with a conspicuous median carina with granulations; transverse sulcus obsolete; eyes moderately prominent, ocular index 3.4; ocular sinus nearly half the diameter of eye in lateral view; postocular lobe narrow. Antenna gradually capitate; eighth, ninth and tenth antennal segments subrectangular, about 1.3 times as wide as long; eleventh segment subglobose and acute apically. Pronotum entirely with foveolae. Prosternum as vertical blade gently separating procoxal apices. Elytron in the base of striae 3, 4 and 5 with denticles ( Figs 5, 6 ). Postmesocoxal sulcus projected ( Fig. 8 ). Hind femur about 2 times its largest width ( Fig. 10 ); pecten with four teeth equidistant, the first approximately 2.5 times the length of the the remaining ones ( Fig. 10 ). Hind tibia gently arched in the basal third ( Fig. 10 ); external face with long lateroventral carina, but not reaching the base of mucro and lateral carina long terminating in a coronal denticle; internal face with a dorsomesal carina reaching tibial apex; mucro about half the width of tibia in the apex ( Fig. 10 ). Fifth male urosternite emarginate and in female bearing an anal notch deeply emarginated and with lateral flanges; margin of fifth urosternite in both sexes with a carina bordering the emargination. Pygidium of male more strongly curved apically in lateral view than female.

Male genitalia. Median lobe ( Fig. 12 ) with length 3.2 times its largest width in apical region; ventral valve rounded. Median area of internal sac with a short Y-shaped sclerite and two longer claw-shaped sclerites with enlarged base; apical region with many denticles ( Fig. 12 ). Tegmen ( Fig. 13 ) with deep emargination between lateral lobes which have long setae mainly on the apex.

Discussion. Merobruchus santiagoi sp. nov. is placed in the subgroup boucheri ( Kingsolver 1988) with its congeneric M. boucheri , from it can be distinguished by the following characters with those of M. boucheri given in parentheses: 1) Integumenal colour: antenna entirely light red (antennal segments 8–10 piceous - Fig. 3 ); 2) Pilosity colour: elytra with light yellow pilosity or grayish (Figs 1,2) (1–7 interstriae of elytra grayish with brown pilosity and 7–11 interstriae light yellow with brown pilosity - Fig. 3 ); 3) base of elytral striae 3, 4 and 5 with denticles ( Figs 5, 6 ) (presence of denticles only in striae 3, 4— Fig. 7 ); 4) postmesocoxal sulcus projected ( Fig. 8 ) (sulcus strongly projected — Fig. 9 ); 5) pecten with four equidistant teeth ( Fig. 10 ) (the first tooth of pecten distant from remaining ones about the length of the second tooth — Fig. 11 ); 6) internal sac of male genitalia in the median area with an unpaired Y-shaped sclerite and paired sclerites, claw-shaped with enlarged base ( Fig.12 ) (unpaired sclerite as a short tooth and subsquare base less sclerotized; paired sclerites as curved teeth — Fig. 14 ).

Type Material. Holotype male. BRAZIL, Rio de Janeiro: Rio de Janeiro, Praia do Flamengo, 6.VIII.1982, C. D. Johnson collector, reared seeds nº 2552-82, reared seeds Pithecellobium scalare , Merobruchus boucheri Kingsolver, C. D. Johnson det. ( DZUP). 11 paratypes with the same data of the holotype (3 MZSP; 2 MNRJ, 6 DZUP). 16 paratypes with the same location, 6.VII.1982, reared seeds Pithecellobium nº 2552, C.D. Johnson ( FSCA). 1 paratype Rio de Janeiro, 1986, M. Macedo col., em sementes de Pithecellobium tortum (Restinga) , Merobruchus sp. n. Pfaffenberger ( DZUP). 14 paratypes Rio de Janeiro, Praia do Flamengo, with the same collector and host plant: 7, VIII.1985 ( FSCA); 7, VI.1986 ( FSCA). 5 paratypes Rio de Janeiro, Marica, June. 1985 ( FSCA). 1 paratype Rondônia: 62KM SW Ariquemes, nr. Fzda. Rancho Grande, 25.Sept.1992, U.Schmitt col., blacklight ( FSCA). 1 paratype BOLIVIA, Santa Cruz de La Sierra: 40 Km NW, Potrerillas del Guenda, 5–20.Nov.2004, Dozier col., black light ( FSCA). 6 paratypes Santa Cruz: Buena Vista (4–6 Km SSE, Flora & Fauna Hotel), 3–8 and 19–22.Oct. 2004, Wappes & Morris cols. ( FSCA). 13 paratypes with same location: 6, 22–31.Oct.2002, Wappes & Morris cols. ( FSCA); 2, 1–8.Nov. 2002, Wappes col. ( FSCA); 1, 5–8, May.2004, Wappes & Cline cols ( FSCA); 1, Hotel Rio Selva (5 Km ESSE), 14.Oct.2000, Wappes & Dozier, cols ( FSCA); 1, 14–19.Oct.2000, M.C. Thomas col. ( FSCA); 2, 5–15. Dec.2001, Thomas & Dozier cols., Tropical Transition Forest ( FSCA).

Host Plants. Merobruchus santiagoi sp. nov. was recorded in seeds of a Fabaceae , Pithecellobium scalare Griseb. (= Pithecellobium tortum Mart. ). Host plants for M.boucheri include P. undulatum (Britt & Rose) Gentry and P. magense (Jacq.) MacBride in North America. P. scalare is an erroneous record for M. boucheri ( Kingsolver 1980:30) since it is for M. santiagoi .

Etymology. The species name is in honour to the Professor Dr. Pe. Jesus Santiago Moure for his contribution to the Departamento de Zoologia of the Universidade Federal do Paraná and his devotion to the study of the Neotropical bees.

Figures

FIGURES 1 – 4. Dorsal view of Merobruchus spp. 1 – 3. Dorsal habitus: 1 – 2, Merobruchus santiagoi sp. nov., 3, M. boucheri. 4. Pygidium of Merobruchus santiagoi sp. nov.

FIGURES 5 – 7. Elytron of Merobruchus spp. 5. Left elytron of Merobruchus santiagoi sp. nov. with denticles at the base of elytral striae 3 – 5. 6 – 7: Details of elytral denticles. 6. Merobruchus santiagoi sp. nov., 7. M. boucheri.

FIGURES 8 – 11. Mesosternum and hind leg of Merobruchus spp. 8 – 9: Mesosternum. 8. Merobruchus santiagoi sp. nov., 9. M. boucheri. 10 – 11: Hind leg. 10. Merobruchus santiagoi sp. nov., 11. M. boucheri.

FIGURES 12 – 15. Male genitalia of Merobruchus spp. 12 – 13. Merobruchus santiagoi sp. nov.: 12. Median lobe, 13. Lateral lobes. 14 – 15. M. boucheri: 14. Median lobe, 15. Lateral lobes.