Variation in Jadera parapectoralis Göllner-Scheiding(Hemiptera: Rhopalidae)

Variação em Jadera parapecoralis (Göllner-Scheiding) (Heteroptera: Rhopalidae)

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SCIENTIFIC NOTE

Variation in Jadera parapectoralis Göllner-Scheiding(Hemiptera: Rhopalidae)

CARL W. SCHAEFER

Dept. of Ecology and Evolutionary Biology, University of Connecticut,

Storrs, Ct 06269-3043,USA

Variação em Jadera parapecoralis (Göllner-Scheiding) (Heteroptera: Rhopalidae)

RESUMO - Um macho de Jadera parapecoralis Göllner-Scheiding, coletado no Rio Grande do Sul, Brazil é comparado com descrição original. Várias diferenças são destacadas.

PALAVRAS-CHAVE: Insecta, Rhopalidae, Jadera.

ABSTRACT - A male specimen of Jadera parapectoralis Göllner-Scheiding, collected on August 30, 2000, in Rio Grande do Sul state, Brazil, is compared to the published description of this species. Several differences are noted.

KEY WORDS: Insecta, Rhopalidae, Jadera.

In her fine revision of Jadera, Göllner-Scheiding (1979) described a new species, Jadera parapectoralis Göllner-Scheiding, 1979, from Argentina and Brazil. As she notes, this species is very close to Jadera pectoralis Stål, 1862. So similar are the two species that both her descriptions of them and her characterizations of them in her key are at times more comparative than absolute. Nevertheless, the two species are distinct, and the distinction is not lessened by my qualifications below of Göllner-Scheiding's (1979) description of J. parapectoralis.

On August 30, 2000, I collected a male J. parapectoralis in Linha Brasil, near Nova Petrópolis, Rio Grande do Sul state, Brazil. My specimen (which is in my collection) differs in some respects from Göllner-Scheiding's description of J. parapectoralis (1979). In order to amplify that description, and in an attempt to make the distinction between the two species more clear, I give these differences here.

Göllner-Scheiding (1979) describes the head as "rötlich bis bräunlich." The dorsum of the Rio Grande do Sul specimen is concolorous with the rest of the dorsal surface (i.e., blackish), except that it is reddish orange just behind each eye and just behind each antenna. This is the same reddish orange as occurs on the sides of the pronotum; as Göllner-Scheiding suggests ("ab Querfurche"), this lateral coloration extends posteriorly from the pronotal collar. The midline of the scutellum is not reddish, and the scutellar tip is only slightly reddish. The entire dorsal surface (clypeus through corium) is beset with small, black, low, bumps (Göllner-Scheiding's "schwarze Warzen"); from each of these a small, black, erect hair arises which contrasts with the whitish, more recumbent, and far more abundant hairs between these bumps. The abdominal sternites' posterior borders are reddish (as described by Göllner-Scheiding); so also is the lateral region of each sternite, although this is obscured by the heavy vestiture of whitish recumbent hairs. Each abdominal spiracle is also reddish.

The rostrum extends nearly to the abdomen (as it does in J. pectoralis).

The paramere of my specimen is more like that of J. parapectoralis than that of J. pectoralis, although its tip is slightly more pointed than in Göllner-Scheiding's figure (1979, Fig. 39). Arising from within the male's genital capsule and extruding from it, is a structure which I have called the cuplike sclerite-cum-median projection (Schaefer 1978) and which Göllner-Scheiding calls "der Mittelspitz des ventralen Hinterrandes." This structure tapers evenly to a somewhat broad apex in J. parapectoralis (and in my specimen), whereas that of J. pectoralis tapers less evenly and more sharply to a narrower apex (cf. Figs. 39 and 43 in Göllner-Scheiding 1979).

J. parapectoralis males are 9.4-9.7 mm long and 2.7-2.8 mm wide; males of J. pectoralis are 10.0-11.1 mm long and 3.0-3.1 mm wide (Göllner-Scheiding 1979). My Rio Grande do Sul male, 9.4 mm long and 3.4 mm wide, is thus somewhat wider than so far recorded for either of the two species.

J. pectoralis seems to occur only in northern Brazil (Pará and Bahia states); J. parapectoralis occurs in Argentina and Brazil (no further data given) (Göllner-Scheiding [1979]; note: Göllner-Scheiding [1983] lists J. pectoralis also from Bolivia and Uruguay, but these are Bayard's record from a time [1943] when J. parapectoralis had not yet been described; Göllner-Scheiding appears to question these records in her 1979 revision of Jadera).

These color differences do not exclude my Rio Grande do Sul specimen from Jadera parapectoralis; they and the greater width of my specimen fall easily within the range of variation to be expected. An enhanced knowledge of this range may help identify specimens of this species, which so closely resembles J. pectoralis but which is clearly a separate and distinct species.

Acknowledgments

I am grateful to the University of Connecticut Research Foundation and to the Entomological Society of America, which helped support my travel to Brazil for the XXI International Congress of Entomology; to Embrapa/Soja, which helped with the subsequent trip through southern Brazil when this specimen was collected; and especially to A.R. Panizzi and J. Newmyer, companions on that trip.

Literature Cited

Received 31/X/00. Accepted 30/VI/01.

• Bayard, E.B. 1943. A monograph of the genus Jadera Stål. Iowa State College. (unpublished M S. Thesis)
• Göllner-Scheiding, U. 1979. Die Gattung Jadera Stål, 1862 (Heteroptera, Rhopalidae). Deutsche Entomol. Z. (N.F.) 26: 47-75.
• Göllner-Scheiding, U. 1983. General-Katalog der Familie Rhopalidae (Heteroptera). Mitt. Zool. Mus. Berlin 59: 37-189.
• Schaefer, C.W. 1978. The genital capsule of the Rhopalidae (Hemiptera: Heteroptera: Coreoidea). Ann. Entomol. Soc. Amer. 71: 659-666.

Publication Dates

• Publication in this collection
  17 June 2002
• Date of issue
  Sept 2001

History

• Received
  31 Oct 2000
• Accepted
  30 June 2001