Mischocyttarus injucundus (de Saussure, 1854)

Silveira, Orlando Tobias, 2006, Revision of the subgenus Kappa de Saussure of Mischocyttarus de Saussure (Hym.; Vespidae, Polistinae, Mischocyttarini), Zootaxa 1321 (1), pp. 1-108 : 92-97

Mischocyttarus injucundus (de Saussure, 1854)

( Figs. 85, 87 , 99, 100 )

Polybia injucunda de Saussure, 1854: 200 , pl. 25, fig. 8; von Ihering, 1904: 183, 184.

Polybia bimarginata Cameron, 1912 (in Richards, 1945, 1978). Lectotype: ♀ Guyana (no date) (anonymous) (BMNH), designated by Richards (1978), examined. N. syn.

Megacanthopus injucundus: Ducke, 1904: 362 ; 1905b: 688, 689, pl. 4, fig. 22; 1907b: 189.

Mischocyttarus injucundus: Ducke, 1918: 353 ; Richards, 1945: 349; Zikán, 1949: 201, figs. 135, 136, 403; Richards, 1978: 302; Carpenter, 1999: 21.

M. injucundus var. injucundus: Richards, 1945: 350 , figs. 35, 42.

M. injucundus var. bimarginatus (Cameron) : Richards, 1945: 351, pls. 1, 4, figs. 134, 135, 183,184. N. syn.

M. injucundus bimarginatus (Cameron) : Richards, 1978: 303. N. syn.

M. injucundus injucundus: Richards 1978: 303 .

M. injucundus bertonii: Fonseca, 1926: 175 (misidentification).

M. jucundus Richards, 1978: 301 . Holotype: ♀ Manaus , AM, Brazil (Roman) (NHRS, Stockholm), examined. N. syn.

M. juruanus Richards, 1978: 302 . Holotype: ♀ Brazil, Amazonas , Rio Juruá, 1902 (Garbe) (MZSP), examined. N. syn.

M. injucundus tingomariae Richards, 1978: 304 . Holotype: ♀ Tingo Maria , Huánuco, Peru, 670 m, 15/ii/47 (Weyrauch) (BMNH), examined; N. syn.

LECTOTYPE: ♀ Brazil, Pará ( MNHN?), designated by Richards (1978), not examined.

FEMALE. Length of fore wing 8 – 10 mm (– 10.5 mm cf. Richards, 1978); head variably transverse from above, less so in smaller specimens, in frontal view low, FHH/ intOW 0.93; clypeus wider than high, H/WClp 0.84, median angle moderately projecting below, apex narrowly truncate; malar space narrow, not more than 1/3 of the height of an antennal socket; tentorial pit as close to eye as to antennal socket; mandible anterior surface without a prominent border; antennal scape very short and wide, L/Wesc 2.19; occeli widely separated, POL a little more than two diameters, POL/OOL more than 2/3; occiput with margin distinct but not very salient at the center, foraminal area shaped ventrally as a shelf; hypostomal lamella narrow; pronotum with lateral fovea (rarely absent; cf. Richards, 1978), pronotal anterior margin medially with the lamella wide and raised but not reflexed, region just behind raised into definite acute secondary margin; humeral region variable, sometimes salient and produced as lateral lobe, carina variably elevated laterally, with lamella black, from above with profile straight ( Fig. 85 ), or less often concave forwards, total width larger than that of mesoscutum, this practically as long as wide, L/WMsc 1.03; fore wing short, LDis/HMpl 1.98, pterostigma about 3.2 times longer than wide; metanotum oblique, little convex, not very protuberant relative to scutellum; inner claw of hind tarsus with the apex narrowly round; propodeum inflated, median furrow variably deep, triangular, dorsal surface sometimes crossed by gross striae ( Fig. 99 ), propodeal valve variable, sometimes narrow, posterior margin of propodeum adjacent to valves strongly oblique as seen from behind, nearly vertical, forming an acute border whose profile is variably curve in lateral view, sometimes looking as if compressed against the propodeal valve, limit between propodeum and lower metapleuron quite distinct, sulcate and shining; first segment of metasoma moderately elongated ( Fig. 87 ), LSI/HMpl 1.18, region just behind the spiracles sometimes parallel sided for a short stretch, more often with the sides diverging promptly from the spiracles, these rarely very prominent, apex about 2.14 times wider than the base, sternum flattened, limit between tergum and sternum marked by a prominent shining edge.

Sculpture: disk of clypeus with dense small punctures, and with more sparse large ones, interstices shining, area close to ventral margin reticulate and moderately shining with a few large punctures; upper part of interantennal area and frons dull with very dense comb­like small to medium sized punctures; mesopleuron with moderately dense small sized punctures, and with more sparse large ones often distributed in a fairly regular dull pattern, otherwise with interstices notably shining, reticulate aspect of cuticle less apparent, sometimes narrow area adjacent to lower metapleuron with irregular depressions; anterolateral region of propodeum with medium to large sized punctures sometimes coalescent ( Fig. 100 ), posterior region around the median furrow sometimes with large to very large coalescent punctures, associated to alterations on the integument’s relief, from small tubercular elevations to strong transverse crests or striae ( Fig. 99 ) extending from side to side.

Vestiture: eyes with hairs inconspicuous.

Color: black; diffuse dorsal streak on gena (sometimes absent), tegula, distal half of first metasomal segment, sometimes humeral region and lateral lower angle of pronotum, part of upper mesepisternal plate, sometimes the scutellum, lower metapleuron, legs, dark reddish brown; apex of mandible, ventral surface of antennal flagellum (sometimes only apex), pronotal tuberculum, articular processes of meso and metapleuron, spot on inner face of fore tibia, metasoma from second to sixth segment (sometimes darker), reddish brown; sometimes an oblique mark on the mandible, lower part of inner orbit, posterior margin of pronotum (sometimes a streak on lateral extremity of carina), anterior third of metanotum, paired medium sized spots on propodeum (sometimes reduced or absent), valvular region, one streak on mid coxa, two streaks on hind coxa, inner distal margin of trochanters, apex of femora, narrow spots on apex of tibiae, narrow inconspicuous distal bands on terga 1–5 and sterna 2–5, spot on dorsum of the fifth segment of fore tarsus, mid and hind tibial spurs, yellow; fore wing with costal region from the base up to pterostigma tinged with light yellowish brown, from this to the apex darkly infuscate, veins correspondingly yellowish up to pterostigma and distal extremity of discal cell.

Variation. Clypeus sometimes partially or nearly completely tinged with reddish brown.

MALE. Length of fore wing 7.5–8 mm; head in frontal view very low and wide, FHH/ intOW 0.87; clypeus wider than high, H/WClp variable between 0.76–0.90, median angle obtuse, apex narrowly rounded; tentorial pit closer to the eye than to antennal socket; antennal scape exceedingly short and wide, L/Wesc just larger than 2, ventral surface of antennomeres with distinct shining tyloids, third antennomere 2.8 to 2.95 times longer than wide, antennal apex variably elongated, with clear indication of being spirally rolled, antennomeres 11–13 slightly flattened below, 12 from 1.65 to 2.6 times longer than wide, 13 from 3.0 to 4.1 times longer than wide, 1.27 to 1.43 times longer than 12; anterior face of fore coxa slightly flattened; clypeus with dense fine punctation, with a few more sparse less conspicuous medium sized punctures; clypeus and frons with dense silvery pubescence, frons also with longer hairs

Color: similar to female; part of the apex of antenna, sometimes an oblique spot on mandible, sometimes a spot on the mesepisternum ventrally, yellow.

NEST. As noted by Ducke (1905 b), nests of M. injucundus tend to grow along a main axis resulting in an elongated comb with central peduncle. Two nests collected in Mamirauá AM, Brazil (Gorayeb & Silveira; MPEG) have such form, one of them measuring 3.5 X 1 cm, with about 30 cells, and the other measuring 2.8 X 1.5 cm also with about 30 cells. Another nest from Caxiuanã, PA, Brazil (Silveira & Dias; MPEG) has an oval shape, the comb measuring 3.3 X 2.3 cm, with about 50 cells and eccentric peduncle. Nests collected in Caxiuanã have the cells with diameter (4.5 mm) a little larger than those from Mamirauá (4 mm). The description presented by Richards (1978: 304) for nests of M. injucundus tingomariae seems to correspond better to nests like those from Mamirauá. According to the author the comb had more or less the shape of a leaf, and the cells measured 2.5 mm in diameter, far less than those of the nests from Mamirauá and Caxiuanã.

Remarks Ducke (1918: 370) mentioned one specimen of the “typical form” of M. injucundus , from the Brazilian state of Bahia in the Berlin Museum. Richards (1945: 350) gave more detailed information on this specimen saying that it is a female collected by “Feireyes”, thus misspelling the name of the German naturalist G. W. Freyreiss. Papávero (1971: 57) says that Freyreiss collected in the states of Minas Gerais, Rio de Janeiro, and Bahia. From the latter place, he sent about eight thousand insects to various European museums during the years of 1817 and 1818. While the stated collecting locality of the Mischocyttarus specimen in the Berlin Museum seems to be correct, it is very improbable that both Ducke (1918) and Richards (1945) grossly misidentified it. Nonetheless, Richards (1978: 303) considered the record of M. injucundus in Bahia as dubious, which shows that he did not reexamine the Berlin specimen.

As defined here, M. injucundus shows great variation in color and morphology, especially regarding the pronotum and propodeum. Part of the specimens show the normal conditions in the group (except for M. bertonii ) with the humeral region little or moderately salient, and the dorsum of the propodeum with normal sculpture. However, some individuals have the humerus exceptionally prominent, forming a distinct lateral lobe. In addition, these specimens have the dorsum of the propodeum crossed by elevated crests in a pattern unique in the genus ( Fig. 99 ). A third group of specimens shows intermediate conditions or combinations of conditions (compare Fig. 100 ). The holotype of M. juruanus from the Juruá River, for example, has the humerus salient but the propodeum presents only an irregular pattern of punctures associated with a symmetrical pair of low tubercles on each side of the median furrow. The most deviant morphology seems to be somewhat correlated with body size, being also marked by the exceptionally transverse shape of the head, and by lighter color marks. The mandible is spotted with yellow, and the clypeus may have the apical region orange­red, as well as the pronotal carina laterally and the dorsal mesepisternal plate. Specimens from Caxiuanã, PA, Brazil, show the most divergent conditions of form and are in average larger, with the first metasomal segment a little longer. They are lighter in color, with more yellow, and the metasoma has a light brown color more similar to that observed in typical injucundus . Specimens from the western parts of Pará state (MPEG), and also one male from Bolivia, Rurrenabaque (BMNH) have similar color characteristics.

Besides differences in sculpture, considerable variation exists in body size across the range of M. injucundus . Specimens from the extreme west of the distribution tend to be smaller, and particularly small are those individuals from the region of Tingo Maria, Peru, collected by Weyrauch and described by Richards (1978) as M. injucundus tingomariae . The head is less transverse, the pronotal carina may be lower at the sides, and in some cases the small punctures on mesopleuron are larger and coarser than usual. However, even those specimens from the neighboring Peruvian localities Sátipo and Previsto may show conditions transitional to the more typical forms of the lower Amazonian localities, so that a diagnosis does not seem to be feasible for tingomariae in respect to injucundus . The pale colors mentioned by Richards (1978: 301) in the description of his new species M. jucundus is certainly caused by the immature condition of the specimen, as recognized by the author himself. Other elements considered by Richards to support the status of M. jucundus are also insufficient, such as the pattern of sculpture of the mesopleuron, which is equivalent to the condition observed in the holotype of M. juruanus .

The variation observed within this species with respect to the propodeal sculpture is unusual. However, because different alternative conditions of morphology could be observed in individuals of one same colony, it is interpreted here as representing intraspecific variation. On June 1994, I. S. Gorayeb and O. T. Silveira collected (by canoe) two colonies on the vegetation of a “varzea” lake in Mamirauá, AM, Brazil. The two nests were on adjacent leaves of an Araceae growing on a dead tree trunk in the lake, and were collected at once with a plastic bag. On the same plant there was a nest of Protopolybia chartergoides , and another of Polistes canadensis was found on the dead trunk. Only after the capture it could be noted that there were actually two nests of a species judged in the occasion to be M. injucundus . Further examination of the specimens showed that some of them had the propodeum crossed by strong crests (or striae, Fig. 99 ). Because of the previous mixing of the colonies at the time of capture, one could not be certain as to the origin of the “deviant” individuals, in much the same way as reported by Richards (unpublished manuscript) in respect to colonies (identified by him as M. bertonii ) collected by M. Cooper in Bolivia (see next species). However, in the case of the nests from Mamirauá, it could be subsequently observed that some specimens showed an intermediate appearance between the “smooth” and “crested” conditions of the propodeum ( Fig. 100 ). In addition, mature pupae removed from each of the nests presented both conditions.

Inspection of older literature and of specimens in the MPEG collection revealed that the deviant pattern of sculpture had not received special attention of previous authors. Three specimens from the region of the Lower Amazon River, Brazil, in the Ducke collection (♀ R. Trombetas, ♀ ♂ Faro, PA; MPEG) actually show the sculpture modification, but Ducke apparently never mentioned this. Only Richards (1978: 303), describing the male of M. injucundus , but without mentioning particular specimens or localities says, “ Propodeal furrow with a strong keel, angles clathrately sculptured ”. Richards (unpublished manuscript) also reported the occurrence of strong striae on the propodeum of a male from Bolivia, Rurrenabaque, identified by him as M. bertonii . Another male from Peru, Loreto (Carpenter & Wenzel, AMNH) with the propodeum striated brings the identification label “ M. injucundus tingomariae ” by J. M. Carpenter. In addition to these records, the striated pattern has been observed in “all” the specimens of various colonies collected in Caxiaunã, PA , Brazil, by Silveira and collaborators ( MPEG) .

Distribution

SOUTH AMERICA: Trinidad, Venezuela, Guyana, Brazil (AP, PA, MA, BA?), Colombia, Ecuador, Peru, Bolivia.

Examined material

BOLIVIA: Beni, 1♂ Rurrenabaque , 270m, 11/v/1979 (M. Cooper) ( BMNH) ;

BRAZIL: Amapá, Macapá , 2♀ (Mazagão?) Fazendinha , 9/xi/1978 (M.F. Torres) ( MPEG) ; 2♀ Campus do IEPA, 22/xi/2000 (O. T. Silveira ) , 1♀ São Joaquim do Pacuí, 14/xii/2001 (J. Madson & J. Chaves), Laranjal do Jari , 1♀ Santa Rosa , 23/ix/2001 (G. Melo) , 3♀ Cajari, 19/v/2001 (O. T. Silveira ) , 2♀ Cajari , 24/v/2001 , 1♀ Cajari , 22/ix/2001 (J. Chaves) , 1♀ Marinho , 4/viii/2000 (J. L. Chaves) , 6♀ 3♂ Sombra da Mata , 9/v/2001 (José Luis & J. Madson), Oiapoque , 2♀ BR­156, 19/x/2001 (J. Madson), 1♀ Cachoeira , 15/xii/2000 (O. T. Silveira) ( IEPA) ; 1♀ Oiapoque , 18/vi/1904 (A. Ducke), Pracuúba, assentamento Pernambuco 1♀ 27/x/2004 , 2♀ 2♂ 29/x/2004 (O. T. Silveira) ( MPEG) ; Amazonas , 1♀ S. Gabriel, R. Negro , 19/viii/1927 (J.F. Zikán) ( IOC) , 1♂ 1♂ Manaus, INPA, 31/vii/1978, (A.Y. Harada) ( INPA) , 5♀ 4♂ Mamirauá , 8/vi/1994 (Gorayeb & Silveira) , 1♀ Tabatinga , x/1904 , 1♀ 2♂ Tefé , 25/ix/1904 (A. Ducke) ( MPEG) ; Maranhão, 1♀ S. Luiz, 4/vi/1907 (A. Ducke) , 1♀ Barreirinhas, Tabocas , 3/iv/2004, Azevedo, G.G. & Amorin, L. R ., 9♀ Urbano Santos, Santo Amaro , 15/v/2004, Azevedo, G.G. & Amorin, L. R. ( MPEG) ; Pará , 1♀ Óbidos (no date) (A. Ducke) , 1♀ Pará, Almeirim , 17/vi/1903 (A. Ducke) , 1♂ Pará , 16/ iv/1900 (A. Ducke) ( MPEG) , 1♂ Belém, Museu Goeldi, 31/i/1968 ( R. Jeanne ) , 1♀ 2♂ Belém, MPEG, Campus de Pesquisa , 22/v/1992 (O. Silveira) , 1♀ Primavera , 18/ii/1987 (M. Zanuto) , 8♀ 1♂ Taciateua , 18/viii/1977 (C. Fonseca) , 1♀ Marajó, Ponta de Pedras , 12/iii/1978 (W. Overal) , 1♀ 1♂ Ponta de Pedras , 3/iii/1979 (W. França) , 1♀ C. Araguaia, Redenção , 24/xi/1978 (W. França) , 3♀ Acará , 7/xii/1977 (M.F. Torres) , 2♀ Marudá , 5/xi/ 1977 (P. Oliveira) , 2♀ Benevides , 5/iv/1979 (F.F. Ramos) , 3♀ Bujarú , 12/i/1978 (W. França) , 1♀ Bujarú , 30/vi/1977 (Waldir & Braack) , 3♀ 4/x/1977, 4♀ 1♂ 6/x/1977, Bujarú (P. Waldir), Melgaço, Caxiuanã, ECFPn, 3♀ iii/1998 (Silveira & Pena), 7♀ vi/1998 (Silveira & Dias), 4♀ 3♂ 20/xi/1998 (Silveira & Pena), 1♀ R. Cuminámirim ( Trombetas ), 26/xii/1906 (A. Ducke) , 2♂ Faro , 3/ix/1907 (A. Ducke), ( MPEG) ; COLOMBIA: Amazonas , 1♂ Leticia , 28/v/1979 ( R. C. Wilkerson) ( FSCA) ; Putumayo, 1♀ (PARATYPE of M. injucundus tingomariae ) Puerto Assis , 350m, 20–23/iii/1972 (M. Cooper) ( BMNH) ; ECUADOR: Napo, 2♀ Tena , 16/xii/1990 (Carpenter & Wenzel) ( AMNH) ; PERU: Loreto, 1♀ Iquitos , 9/viii/1906 (A. Ducke) ( MPEG) , 1♀ 80 Km NE Iquitos , 24/xii/1990 , 1♂ R. Sucusari "at Napo", 24/xii/1990 (Carpenter & Wenzel) ( AMNH) ; Huánuco, 1♀ 1♂ Tingo Maria, R. Huallaga , 700m, 1/iv/1940 (Weyrauch) , 1♀ Tingo Maria, 670m, (no date) (Weyrauch) ( IOC) , 2♀ 2♂ (PARATYPES of M. injucundus tingomariae ), Tingo Maria, R. Huallaga , 670m, v/47 (Weyrauch) ( IMLA) , 1♀ (PARATYPE of M. injucundus tingomariae ), Tingo Maria, 670m (no date) (Weyrauch) ( BMNH) ; Ucayali, 1♀ Pucallpa , 31/iii/1965 (J.M. Schunke) , 1♀ Previsto, Cord. Azul , 760m, 14/v/1965 (J.M. Schunke) ( BMNH) , 1♀ Satipo, 600m, 1/viii/41 (Weyrauch) ( IOC) ; TRINIDAD: 1♀ vii/33 , 1♀ i/35 (FitzGerald), 2♀ 12/ii/1985, 1♂ 25/v/1985 (F.D. Bennett) ( BMNH) ; VENEZUELA: 1♀ Orinoco Delta, Cano Mariusa , 140 Km NE Barrancas, 29/vii/ 1958 (A. Menke) ( UCDC) .

Figures

FIGURES 81–96. M. bertonii: 81, mesosoma part dorsal, 86, T1; M. mysticus sp. n.: 82, mesosoma part dorsal, 83, T1; M. schunkei: 84, T1, 92, male antenna; M. injucundus: 85, mesosoma part dorsal, 87, T1; M. pertinax sp. n.: 88, T1, 89, mesosoma part dorsal; M. timbira sp. n.: 90, male antenna, 93, mesosoma part dorsal, 95, T1; M. porantin sp. n.: 91, male antenna, 94, mesosoma part dorsal, 96, T1.

FIGURES 97–100. (SEM images) M. imitator: 97, apical aspect of the female clypeus; M. socialis: 98, same as anterior; M. injucundus: 99, propodeum (strongly striate) lateral view, 97, propodeum (moderately striate) dorsal view.