Plangiopsidini Cadeña-Castaneda, 2015

Massa, Bruno, 2023, Biodiversity hotspot in the Sangha Trinational Protected Area revealed through Orthoptera Tettigoniidae, Zootaxa 5331 (1), pp. 1-67 : 12-13

Tribe Plangiopsidini Cadeña-Castaneda, 2015

According to Cadeña-Castaneda (2015) the tribe Plangiopsidini is diagnosed based on the following characters: face oval, eyes subcircular, pronotal disc flat and with small denticulations on lateral carina, lateral lobes compact, curving progressively to the humeral sinus, tegmen lanceolate, fore coxae armed with a spine, tympanic organs exposed in the exterior side and conchate in the interior side, meso- and metasternum with lateral lobes rounded or acuminate, tenth tergite without modification, male cerci simple and armed with apical spine. Females with ovipositor as long as a third of the length of the hind femora, curving sharply upwards, valves with crenulate margins, upper valve with cuticular invaginations from the base to the apex (variable character). Among these characters, only small denticulations on the lateral carina are absent in some species (e.g., Plangiopsis adeps ), thus we could remove this character from those belonging to the tribe. Presently only the genera Plangiopsis Karsch, 1889 ( Figs. 5a–5d ) and Plangiola Bolívar, 1906 ( Fig. 6d ) are listed within the tribe Plangiopsidini . Plangiola is a little different, having eyes more elongate than in the species of Plangiopsis .

Another character that has not been previously considered is the shape of the fastigium of the vertex, which is a little raised, with a rather wide space between the antennae, different from the tribe Holochlorini Brunner von Wattenwyl, 1878 , where the fastigium of the vertex is raised, narrow, and the space between the antennae is very small (e.g., genera Holochlora , Arantia , Dapanera , etc.) ( Figs. 7a–7d ). The fastigium of the vertex in the species of the tribe Plangiopsidini shows clearly two lateral dimples, not so evident in the species belonging to the tribe Holochlorini ( Figs. 5a–5d , 6a–6d , 7a–7d ).

When Sĵstedt (1902) described the genus Bongeia (type species: B. puncticollis from Cameroon), he wrote that it is most closely related to the genus Tapeina Brunner von Wattenwyl, 1878 . Because the genus Tapeina Lepeletier & Audinet-Serville in Latreille, 1828 already existed for a neotropical Cerambycidae, Bolívar (1906) renamed it as Tapiena and described Tapiena minor from Ghana (West Africa), the only African species for this genus. The genus Tapiena is an east Asian-Indonesian genus belonging to the tribe Holochlorini , with only one African species; actually the genus is heterogeneous, but the fastigium of the type species, T. acutangula ( Brunner von Wattenwyl, 1878) , is narrow, like in the other Holochlorini . The African species, T. minor , recently again recorded from Ghana by Naskrecki (2008), differs in this character from T. acutangula , with its fastigium wide between the antennae ( Fig. 6c ), much like that of other genera included in the tribe Plangiopsidini . This difference leaves little doubt that Tapiena minor does not actually belong to the tribe Holochlorini , but instead to the tribe Plangiopsidini , with which it shares the other characters of the tribe. Consequently, T. minor does not belong to the genus Tapiena , but to an undescribed genus, described below as Afrotapiena n. gen. Therefore, the genus Tapiena is definitively excluded from Africa, distributed only in east Asia and Indonesia.

Concerning the genus Bongeia (type species B. puncticollis ; see Fig. 6a ), it was placed within Psyrae (presently tribe Holochlorini ), like Tapiena , but also in this case the fastigium, as well as other characters, are more similar to those of the other genera included in the tribe Plangiopsidini . Furthermore, the genus Itokiia Sj ̂stedt, 1902 (type species: I. silvarum Sj ̂stedt, 1902; see Fig. 6d ), was also included within Psyrae ( Holochlorini ), but its characters, including the fastigium of the vertex, suggests it also belongs to the tribe Plangiopsidini .

Thus, the characters of the tribe Plangiopsidini Cadeña-Castaneda, 2015 should be: face oval, eyes subcircular, rounded or elongate, anterior margin of pronotum incurved, posterior margin rounded, pronotal disc flat with or without small denticulations on lateral carina, lateral lobes compact, curving progressively to the humeral sinus, higher than long or as high as long, tegmen lanceolate, second pair of wings longer than tegmina, speculum on right tegmen present or absent, fore coxae armed with a spine, conchate tympana in inner side, open in the outer side, tenth tergite without modification, male cerci simple with or without apical spine, styli present. Ovipositor gently upcurved or curving sharply upwards.

The following genera therefore are considered to belong to the tribe Plangiopsidini : Plangiopsis (four species: P. semiconchata Karsch, 1889 , P. foraminata Karsch, 1892 , P. adeps Karsch, 1896 , P. nouabalensis n. sp.), Plangiola (only one species: P. herbacea ), Bongeia (two species: B. puncticollis , B. brevicauda Ebner, 1943 ), Itokiia (only one species: I. silvarum ) and Afrotapiena n. gen. (only one species: A. minor ) (see Figs. 5a–5d , 6a–6d , 8a–8d , 9a–9c , 10a–10f , 11a–11f ).

Figures

FIGURE 5. Frontal view of the head of Plangiopsis nouabalensis n. sp. (a), P. foraminata Karsch, 1892 (b), P. adeps Karsch, 1896 (c) and P. semiconchata Karsch, 1889 (d), belonging to the tribe Plangiopsidini Cadeña-Castaneda, 2015. Arrows indicate the lateral dimples on the fastigium of vertex.

FIGURE 6. Frontal view of the head of species, whose genera are here included in the tribe Plangiopsidini: Bongeia puncticollis Sĵstedt, 1902 (a), Plangiola herbacea Bolívar, 1906 (b), Afrotapiena n. gen. minor Bolívar, 1906 (before Tapiena minor) (c), Itokiia silvarum Sĵstedt, 1902 (d). Arrows indicate the lateral dimples on the fastigium of vertex.

FIGURE 7. Frontal and dorsal view of the head of the genera Arantia Stål, 1874 (a, b) and Holochlora Stål, 1873 (c, d), both belonging to the tribe Holochlorini Brunner von Wattenwyl, 1878. Arrows indicate the narrowness of fastigium.

FIGURE 8. Habitus in lateral view of Plangiopsis nouabalensis n. sp. (a), P. semiconchata Karsch, 1889 (b), P. foraminata Karsch, 1892 (c), Plangiopsis adeps Karsch, 1896 (d).

FIGURE 9. Habitus in lateral view of Bongeia puncticollis Sĵstedt, 1902 (a), Itokiia silvarum Sĵstedt, 1902 (b), Tapiena (presently Afrotapiena n. gen.) minor Bolívar, 1906, syntype (c).

FIGURE 10. Lateral view of the headand pronotum of species here considered belonging to the tribe Plangiopsidini: Plangiopsis nouabalensis n. sp. (a), Plangiopsis semiconchata Karsch, 1889 (b), P. adeps Karsch, 1896 (c), Bongeia puncticollis Sĵstedt, 1902 (d), Plangiola herbacea Bolívar, 1906 (e), Afrotapiena n. gen. (previously Tapiena) minor Bolívar, 1906 (f).

FIGURE 11. Dorsal view of head, pronotum and stridulatory area of Plangiopsis nouabalensis n. sp. (a), P. semiconchata Karsch, 1889 (b), P. foraminata Karsch, 1892 (c), P. adeps Karsch, 1896 (d), Bongeia puncticollis Sjöstedt, 1902 (♀ holotypus) (e), Itokiia silvarum Sjöstedt, 1902 (♁ holotypus) (f).