Progoniogryllus, Ma & Jing & Zheng, 2021

Ma, Libin, Jing, Xuan & Zheng, Yanna, 2021, Integrative taxonomy base on morphology and molecular phylogeny with description of a new genus, Progoniogryllus gen. nov. and two new species (Orthoptera: Grylloidea: Gryllidae; Gryllinae), Zootaxa 4995 (3), pp. 523-536 : 529-530

Genus Progoniogryllus gen. nov.

Type species: Progoniogryllus rotundus sp. nov., here designated.

Diagnosis. Size small for Gryllinae species. Colored dark brown and ornamented with patches and stripes in light color, especially, above eyes there are backward forked stripes. Pronotum pubescent, armed with straight fore and hind margins and the former slightly narrower than the hind. Elytra short, far from supra-anal plate; basal and apical area of elytra rather short and almost similar in length; possessing two oblique veins and developed mirror; and media fold (fan) between apical part of lateral and dorsal area developed and expanded. Fore tibiae armed with outer tympanum and the inner one absent. Epiphallus almost without middle lobe and gap between lateral lobes rather broad. Ectoparamere simple and shaped as wide blade. Particularly, testis of the new unusually developed and occupies a large space in the abdominal cavity.

Molecular phylogeny. To infer the taxonomic status of the new genus, we constructed phylogenetic relationship of two species of the new genus, 32 other Gryllinae species and three species of Gryllotalpidae ( Fig. 2 ). The tree presented that the new taxa is included in the lineage of Modicogryllini and relevant species. Within the species we concluded, the new ones are much closer to Goniogryllus . Although they are distinct, it is significant that both the new and Goniogryllus bear similar coloration.

Courtship behavior. If the male and female are placed in a box, the male will make a courtship call and approach female. The male will point the end of his abdomen at the female, and it can be observed that there is a spermatophore hanging at the end of the abdomen, but the female seems to avoid the male. Usually, the female's avoidance will not cause the male to give up, he will continue to get close to the female, constantly chase and point his tail up at the female in different positions. After courtship for about 7–15 minutes, the male keeps falling back and takes the opportunity to get under the female's body. After the external genitalia are connected, the copulation commences. During the mating, it is found that the female and the male twist at a certain angle ( Fig. 3 ). The whole process lasts about 2 minutes, then the female leaves and the copulation ends.

Etymology. The name refers to the position of the new in the phylogenic tree (fig. 2) in the article.

Included species: Progoniogryllus rotundus sp. nov. and Progoniogryllus directus sp. nov.

Remarks. External appearance of the new genus slightly resembles the genera Parasongella Otte, 1987 , Callogryllus Sjöstedt, 1910 and Goniogryllus Chopard, 1936 since they both possess short elytra (or not) and bear yellowish stripes above eyes, but the tegmina of the new taxa are somewhat longer and possess an intact mirror, and the genitalia of the new taxa is distinct from the above.

Parasongella includes three species, Parasongella ornaticeps ( Chopard, 1969) (type locality: Thailand), Parasongella japonica Ichikawa, 2001 (type locality: Japan) and Parasongella nigriceps Otte, 1987 (type locality: Tanzania). Although considered in the same genus, their male genitalia are rather different from each other. The type species, P. nigriceps , bears genitalia that are very similar to Songella species and the clypeus is strongly upwards bent. The genitalic complex of P. japonica is very similar to the species of Goniogryllus , but that of P. ornaticeps is different from the former two. Thus, we do not think it warranted to combine those three species into Parasongella ( Ichikawa, 2001) .

The male genitalia of the new genus is similar to the genus Gryllodes Saussure, 1874 , and, their elytra is rather similar to each other. But the body of Gryllodes species is somewhat dorsoventrally compressed and that of the new genus is normal. Based on the phylogenic relationship which was established based on gene sequences, these two genera are distantly related.

Figures

FIGURE 2. The phylogenetic relationship among Gryllinae species, obtained by Maximum likelihood inference. Outgroups are Gryllotalpa sp_Moz, Gryllotalpa africana and Gryllotalpa sp_PNG. Abbreviations: Van (Vanuatu, Espiritu Santo), Moz (Mozambique Yemen, Socotra), PNG (PNG, Mt Wilhelm), NC (New Caledonia), India (India, Kerala).

FIGURE 3. Copulation of P. directus sp. nov. (female above male).