Geotomus granulosus, Lis & Lis, 2022

Lis, Jerzy A. & Lis, Barbara, 2022, Geotomus granulosus, a peculiar sehirine-like new species of the subfamily Cydninae (Hemiptera: Heteroptera: Cydnidae) from Burundi, Zootaxa 5087 (3), pp. 489-493 : 490-492

Geotomus granulosus sp. n.

( Fig. 1B–E , 2A–D )

Etymology: The specific name refers to the unique dorsal body surface in the species; it is the Latin adjective granulosus , meaning “granulous”, “having small grains”.

Diagnosis: In the absence of the subapical pair of hair-like setae on the clypeus, this new species is similar to three other Afrotropical species, namely G. palustris Linnavuori, 1977 , G. radialis Signoret, 1883 , and G. remedellii Mancini, 1954 . However, it has a peculiar sehirine-like appearance in its dorsal habitus resembling species of Ochetostethus Fieber, 1860 and Ochetostethomorpha Schumacher, 1913 (subfamily Sehirinae ). Therefore, the new species can easily be separated from all its African congeners. To date, Fromundus singularis (Horváth, 1904) was the only Afrotropical species that has a similar dorsal body structure ( Fig. 1A ) and superficially resembles the sehirine genus Ochetostethus (see: Linnavuori 1993; Lis 1996). Nevertheless, these two species represent two different genera, and what is also essential strongly differ morphologically (what can be seen when you compare Figures 1A and 1B ). Moreover, the new species differs from all its known congeners in the unique shape of the hair-like setae constituting the body chaetotaxy, which are peculiarly broadened in the apical part ( Fig. 1E ). This character is unknown in other species of this genus.

Description: Body ( Fig. 1B ) ovate, relatively depressed, ventrally and dorsally opaque, entirely black or brownish-black, antennae and tarsi brown, somewhat lighter in the shade than remaining body parts. Head, pronotum and scutellum granulose, roughened with distinct large granules; hemelytra with smaller granules and numerous deep punctures. Hair-like setae on the head, the pronotal disc and the abdomen peculiarly broadened in the apical part ( Fig. 1E ).

Head broader than long, its anterior part slightly pointed downward ( Fig. 1C ) what makes its anterior margins looking broadly ovate in a dorsal view ( Fig. 1D ); each paraclypeus with two primary hair-like setae (III, IV), and a single secondary submarginal seta; all setae peculiarly broadened in the apical part ( Fig. 1E ); clypeus free, a little longer than paraclypei, broadest in its mid-length, subapically without a pair of hair-like setae ( Fig. 1C ); eyes large, protruding, their ommatidia granulose, apical seta (VI) absent ( Fig. 1C–D ); ocular index 2.80–3.30; interocellar index 7.43–7.72; interocellar distance 4.33–4.42 times a distance of an ocellus from the eye; head ventral surface granulose; rostrum reaching the anterior margin of the mid-coxae ( Fig. 2A ).

Thorax ( Fig. 1B ). Pronotum about 1.9–2.2 times broader than long; anterior margin deeply angularly insinuated behind the head; transverse discal impression behind calli coarse and well developed; lateral margins slightly crenulated; sublateral margins with five hair-like setae of the same shape as those on paraclypei; prosternal carina well-developed, deep; anterior and posterior convexities of propleuron coarsely punctured with large punctures, propleural depression broad. Scutellum elongated, slightly convex. Mesopleural and metapleural evaporatoria large, triangular, with many distinct, large and coarse punctures; remaining parts of pleura distinctly coarsely punctured; peritremal disc lobe-like ( Fig. 2B ). Corium coarsely punctured, the costal vein (C) coalescent with the subcostal vein (Sc), the cubital vein (Cu) widely separated from radial + medial (R+M) veins, the first anal vein (1A) present, the second anal vein (2A) absent; R+M and Cu distinctly elevated; costal margin somewhat crenulated, basally with a single hair-like seta of the same shape as those on paraclypei and pronotal margins; hypocostal laminae broad and coarsely punctured; membrane almost reaching the tip of the abdomen, whitish with dark veins. Metathoracic wing ( Fig. 2D ) with the subcostal vein (Sc) coalescent with the radial vein (R); apical branches of R and M entirely noncoalescent with each other; hamus in the radial cell absent; cross vein r-m absent; the postcubital vein (pCu) present; all three anal veins (1A, 2A, 3A) present; stridulitrum present on the basal half of the first anal vein (1A).

Abdomen. Abdominal sterna more or less polished, bearing numerous large punctures; eigth tergites each with a single, broadened apically, hair-like seta. Female genital plates typical of the genus. Spermatheca ( Fig. 2C ) with a hemispherical, slightly mushroom-shaped receptacle; intermediate spermathecal part long and straight distally; distal and proximal flange well developed, the distal larger than the proximal; distal duct long and coiled; a dilatation-invagination narrow and elongate, somewhat pear-shaped.

Legs. Anterior tibiae slightly broadened apically, laterally with numerous short spines and setae. Posterior femora with numerous short setae on margins, posterior margin with a single very small subapical blunt tubercle. Hind tibiae cylindrical in diameter with numerous short spines and setae on lateral margins.

Measurements (in mm, females only): body length: 3.58–3.63; body width: 2.07–2.20; head length: 0.59–0.68; head width: 0.910–0.94; pronotum length: 1.00–1.25; pronotum width: 2.08–2.21; scutellum length: 1.67–1.69; scutellum width: 1.26–1.28; length of antennal segments I–V: 0.19–0.20: 0.13–0.14: 0.17–0.21: 0.22–0.26: 0.34–0.36

Type material: Holotype female: “ Burundi, Ostafr [ika], Umg [ebung] Bujumbura, 26 I 84, Heiss ”; Collection E. Heiss, Innsbruck ( IBUO) . Paratypes: two females, same data as the holotype ( IBUO). Prof. E. Heiss has collected the type specimens in the vicinity of the Bujumbura city, situated on the northeastern shore of Lake Tanganyika .

Figures

FIGURE 1. A—Fromundus singularis, Senegal, Kedougou (IBUO), B–E—Geotomus granulosus, holotype: body, dorsal view (A–B); head, in frontal (C) and dorsal (D) view; hair-like setae on paraclypei (E).

FIGURE 2. Geotomus granulosus (A, B—holotype; C, D—paratype): A—head, pro- and mesothorax; B—evaporatoria (mse—mesothoracic evaporatorium, mte—metathoracic evaporatorium, pd—peritremal disc); C—spermatheca (dd—distal part of spermathecal duct, dfl—distal flanges, dil—dilatation of the spermathecal duct, ip—intermediate part, pfl—proximal flanges); metathoracic wing venation (1A, 2A, 3A—anal veins, aCu—anterior cubital vein, Icl—interclaval veins, M—apical branch of median vein, pCu—posterior cubital vein, R—apical branch of radial vein, Sc+R—subcostal [Sc] and radial [R] vein, str—stridulitrum).