Paramecocephala bachmanni Frey-da-Silva and Grazia, 2002

de Barros, Lurdiana Dayse, Barão, Kim Ribeiro & Grazia, Jocelia, 2022, Taxonomic updates on the Mecocephala group (Hemiptera: Pentatomidae): redescription of Mecocephala Dallas and Paramecocephala Benvegnú, Journal of Natural History (J. Nat. Hist.) 55 (43 - 44), pp. 2691-2747 : 2733

Paramecocephala bachmanni Frey-da-Silva and Grazia, 2002

( Figures 11b , 12b , 13e , 15 , 29 ; Table 2)

Paramecocephala bachmanni Frey-da-Silva, Grazia and Fernandes, 2002a: 214–216 , figs 1, 4, 12, 19, 26, 33, 52; Ruschel et al. 2013: 554; Coscarón 2017: 230.

Type material examined. ARGENTINA: BUENOS AIRES: Holotype, m*, Gral. [General] Alvarado, Miramar , 20 November 1946, Bachmann leg. ( MACN) <illustrated specimen> . Paratype, ARGENTINA: BUENOS AIRES: f*, Gral. [General] Alvarado, Miramar , 15 November 1946, Bachmann leg. ( MCNZ –182384) <illustrated specimen> .

Diagnosis. Body colour greyish brown. Apex of mandibular plates convex. Clypeus uniformly wider ( Figure 11b ). Anterolateral margins of pronotum straight; outline crenulate, punctate ( Figure 11b ). Each peritreme of ESES reaching about 1/3 of the distance to lateral margin of evaporatorium, median furrow of each peritreme short, reaching less than half of peritreme; outer margins of metapleural evaporatorium straight; evaporatorium on mesopleuron reaching the posterolateral angles and outer margin ( Figure 13e ). Foveae equal to the diameter of a compound eye ( Figure 15a ). Legs not concolourous with body ventral colour ( Figure 15b ). Hemelytra surpassing apex of body ( Figure 15a ). Connexivum exposed. Trichobothria lateral to the imaginary longitudinal line tangent to the spiracles.

Male genitalia. Pygophore trapezoidal, posterolateral angles rounded ( Figure 15d–g ). Genital cup narrow, occupying half of the length of pygophore. Medial region of dorsal rim notched, and extension of dorsal rim well developed ( Figure 15d–e ). Area between layers of ventral rim excavated. Superior layer of ventral rim covering parameres, with two pairs of processes ( Figure 15f ). Inferior layer of ventral rim without processes ( Figure 15g ).

Female genitalia. Posterior margins of valvifers 8 rectlinear. Posterior margins of laterotergites 8 straight. Anterior margins of valvifers 9 straight, posterior margins convex ( Figure 15h–i ). Laterotergites 9 surpassing the abdominal tergite 8.

Measurements. See Table 2.

Distribution. Argentina (Buenos Aires) ( Figure 29 ).

Remarks. Paramecocephala bachmanni differs from its congeners by head slightly wider than long, labium not reaching the posterior portion of abdominal sternite 4, and posterior margins of valvifers 8 arched. Shares with P. bergrothi the extension of dorsal rim well developed in a biconvex projection.

Figures

Figure 11. Head and pronotum of Paramecocephala in dorsal view. (a) Paramecocephala australis; (b) Paramecocephala bachmanni; (c) Paramecocephala bergrothi; (d) Paramecocephala foveata; (e) Paramecocephala fusca; (f) Paramecocephala guianensis; (g) Paramecocephala subsolana; (h) Paramecocephala uruguayensis; (i) Paramecocephala helenae sp. nov. Scale bars = 0.5 mm.

Figure 12. Head and prothorax of Paramecocephala in lateral view. (a) Paramecocephala australis; (b) Paramecocephala bachmanni; (c) Paramecocephala bergrothi; (d) Paramecocephala foveata; (e) Paramecocephala fusca; (f) Paramecocephala guianensis; (g) Paramecocephala subsolana; (h) Paramecocephala uruguayensis; (i) Paramecocephala helenae sp. nov. Scale bars = 0.5 mm.

Figure 13. Thoracic external scent efferent system (ESES) of metasternal glands of Paramecocephala. (a–d) Paramecocephala australis; (e) Paramecocephala bachmanni; (f) Paramecocephala bergrothi; (g) Paramecocephala foveata; (h–j) Paramecocephala fusca; (k) Paramecocephala guianensis; (l) Paramecocephala subsolana; (m) Paramecocephala uruguayensis; (n) Paramecocephala helenae sp. nov. (a, e–g, k–n) meso- and metapleural in ventral view; (b–d, h–j) scanning electron microscopy images of characters of ESES of metasternal glands. Abbreviations: cx2 – mesocoxae; cx3 – metacoxae; ev – evaporatorium; ms – mesopleuron; mt – metapleuron; mts – metathoracic spiracle; o – ostiole; om – outer margin; pod – periostiolar depression. Scale bars: a, e–g, k–n = 0.5 mm; b, h = 500 µm; c–d, i–j = 200 µm.

Figure 15. Paramecocephala bachmanni Frey-da-Silva and Grazia, 2002. (a–c) Habitus of holotype in dorsal, ventral and lateral view; (d–e) pygophore in dorsal view; (f) pygophore in superior view; (g) pygophore in ventral view; (h–i) genital plates in posteroventral and lateral view. Abbreviations: alvr – area between layers of ventral rim; edr – extension of dorsal rim of pygophore; ilvr – inferior layer of ventral rim of pygophore; mpdr – marginal process of dorsal rim; par – paramere; pslvr – process of superior layer of ventral rim; slvr – superior layer of ventral rim of pygophore; x – segment X. Scale bars: a–c = 2.0 mm; d,f–g = 1.0 mm; h–i = 0.5 mm.

Figure 29. Map showing the geographical distribution of Mecocephala and Paramecocephala species. Yellow star = new record of P. subsolana.