Umbrageocoris, Kóbor, 2019

Kóbor, Péter, 2019, Umbrageocoris Kondorosyi: A New Genus And Species Of Big-Eyed Bugs From New Guinea (Heteroptera: Lygaeoidea: Geocoridae), Acta Zoologica Academiae Scientiarum Hungaricae 65 (1), pp. 1-8 : 3-4

Umbrageocoris gen. n.

( Figs1–4 )

Type species: Umbrageocoris kondorosyi sp. n.

Description – Body elongate oval; integument shiny, lacking conspicuous pubescence ( Fig. 1A ). Head pentagonal; surface smooth, shiny; vertex with a thin longitudinal furrow extending from between the ocelli to middle of clypeus. Eyes big, reniform, moderately stylate; ocular sulcus slightly visible but complete ( Fig. 2B ). Proportion of antennal segments: segment I shortest, segment II longest, segments III and IV subequal in length. Margins of jugae somewhat projecting, forming a U­shaped rim; labial trough closes at midline of head, suture formed by margins extending to base of head. Labial segment I not reaching base of head, segment II shortest, segment III subequal to I, segment IV longest, apex reaching about the line of metacoxae. Thorax. Pronotum trapezoidal with anterior margin and edges broadly convex. Surface shiny with coarse, dense punctation except anterior and posterior margins, callosities and humeral angles. Margins, callosities and humeral angles slightly elevated. Anterior half of lateral margins of pronotum slightly carinate and impressed behind callosities. Scutellum almost equilateral, sharply pointed apically, surface with dense punctuation except trifurcate median carina. Apical part of carina expressed, elevated, basal parts reduced but visible. Hemelytron macropterous with well­developed membrane, length of membrane subequal to length of corium. Margins of clavus converging to apex; claval commissure reduced, inconspicuous. Costal margin suddenly widening at third of length; costal region widest at about half of length. Thoracic pleurites and sternites with dense, strong punctation except supracoxal lobes, peritreme of metathoracic scent gland and dorsal edge of metapleurite ( Fig. 2A ). Peritreme of metathoracic scent gland situated ventro­laterally, near anterior margin of metathorax; shape ear­like, dorsal rim slightly curved downwards. Evaporative area small, narrow, not reaching dorsal margin of supracoxal lobes ( Figs 2B , 4B ). Abdomen shiny, with sparse fine pubescence. Abdominal tergites III–V with surface strongly wrinkled ( Fig. 2D ). Trichobotria on connexiva V–VI conspicuously bulging ( Fig. 2C ). Abdominal venter finely rugous. Genitalia: Male pygophore with conspicuous lateral processes on dorsal half of the opening; paramere ( Fig. 3 ) with blade elongate, somewhat curved, lacking conspicuous setae or pubescence; gonoporal process with 10 coils.

Etymology – The name of the is composed of the Latin noun umbra (= shade, night, darkness), referring to the dorsum being dark brownish laterally margined with ochraceous, endowing it with a “shaded look”, and Geocoris , a closely related genus. Gender masculine.

Diagnosis – Umbrageocoris gen. n. can be separated from other geocorines of the region with combination of following characters: labial through Y­shaped with suture reaching base of head; labial segment II shorter than III, segment IV longest; clavus gradually narrowing towards apex, claval commissure reduced; corium punctate along veins; peritreme and evaporatorium of metathoracic scent gland as in Fig. 4B ; surface of abdominal terga III and IV rugous medially; male paramere slender, blade narrow, curved, surface lacking pubescence.

Remarks – Umbrageocoris gen. n. resembling most to the Australian genus Stylogeocoris Montandon, 1907 , nevertheless there are some remarkable differences separating these genera. Based on MALIPATIL’s (1994) revisionary work on Stylogeocoris and studying the holotype of Stylogeocoris biroi Montandon, 1907 (HNHM), this genus can be diagnosed with the combination of following characters: labial segment 2 and 3 subequal in length; ocular sulcus complete, distinct; margins of clavus almost parallel, claval commissure developed; abdominal terga III and IV punctate. In Umbrageocoris labial segment II is conspicuously shorter than segment III; margins of clavus gradually converging, claval commissure reduced; abdominal terga III and IV rather wrinkly than punctate. Male paramere is stouter, more curved in Stylogeocoris compared to Umbrageocoris . Furthermore, paramere of Umbrageocoris is lacking pubescence. Comparing to the Geocoris Fallén, 1814 distributed in the archipelago ( Geocoris willeyi Kirkaldy, 1905 and G. leopoldi Schouteden, 1933; holotypes examined) the following differences can be observed: the new genus is more slender in general appearance than the other two species; head more pentagonal, ocular sulcus slight, but complete, not reduced; pronotal callosities more developed in Umbrageocoris ; apical part of trifurcate carina of scutellum slight, but not reduced; corium of hemelytron without punctation in intervanals. In terms of Germalus , the most remarkable differences are the proportions of labial segment II–III (similarly as in the case of Stylogeocoris ) and the arrangement of peritreme of metathoracic scent gland ( Fig. 4A, B ).

If looking at genus Geocoris in general, species similar to Umbrageocoris can be found in other biogeographical regions. Nevertheless, it has to be noted that more authors consider the genus Geocoris “an ill­defined group of species belonging to perhaps several distinct genera” ( READIO & SWEET 1982, MALIPATIL 1994) which is in need of a thorough revision. Based on the literature available and own observation, the author of recent study supports this opinion and concludes that the given combination of characters is eligible to separate this taxon on generic level from other members of New Guinean fauna. One of the most convincing characters is the arrangement and shape of the outer structures of metathoracic scent efferent apparatus ( Fig. 4 ), which is showing remarkable differences if compared to Geocoris and Germalus species of the region. Based on the results of recent study and unpublished findings of the author this character might have significant value in taxonomy and phylogeny of Geocoridae . Similar findings were concluded by KMENT and VILIMOVÁ (2010) in family Tessaratomidae ( Heteroptera : Pentatomoidea).

Figures

Fig. 1. Habitus of Umbrageocoris kondorosyi sp. n.: A = dorsal (holotype, HNHM), B = lateral (paratype, BMNH)

Fig. 2. Photos of Umbrageocoris kondorosyi sp. n.: A = dorsum of head, B = venter of head, C = peritreme and evaporative area of metathoracic scent gland, D = dorsolateral trichobotria of abdomen

Fig. 3. Male paramere of Umbrageocoris kondorosyi sp. n. from different angles

Fig. 4. Peritreme of metathoracic scent gland in New Guinean Geocorinae: A = Germalus Stål, 1862; B = Umbrageocoris gen. n.; C = Geocoris Fallén, 1814. Legend: cx2 = mesocoxa, ev = evaporatorium, pe = peritreme, o = ostiole, ves = vestibular scar