Heteracris guineensis (Krauss, 1890)

Wandji, Alain Christel, Yetchom-Fondjo, Jeanne Agrippine, Kekeunou, Sévilor, Kenne, Martin, Missoup, Alain Didier, Tindo, Maurice, Simeu-Noutchom, Alain, Mbadjoun-Nzike, Marcelle, Xu, Sheng-Quan, Djomnang-Nkwala, Alfiery Laurel & Fomena, Abraham, 2021, Description of Heteracris lecoqi Yetchom-Fondjo & Kekeunou sp. nov. and Heteracris hannai Wandji & Kekeunou sp. nov. and redescription of Heteracris guineensis (Krauss, 1890) (Orthoptera: Acrididae) with comments on its ecology in the Southern part of Cameroon, Zootaxa 4915 (1), pp. 95-106 : 101-102

Heteracris guineensis (Krauss, 1890)

Synonymy: Eyprepocnemis guineensis Krauss, 1890 ; Thisoicetrus guineensis Sj ̂stedt. 1918; Heteracris aurantiacus (Uvarov, 1921) ; Heteracris maculosa (Krauss, 1890) .

Syntypes: West Tropical Africa , Togo, Misah ̂he, SMN Stuttgart .

Material examined:

1 male from Balamba (4°24’796”N, 11°14’866”E), 16 males and 7 females from Mfou (3’48”364”N, 11°40’496”E), 19 males and 11 females from Talba (4°37’704”N, 11°29’815”E), 1 female from Babété (5°35’520”N, 10°15’373”E), 12 males and 2 females from Bangoulap (5°06’.013”N, 10°32’.332”E), 8 males and 6 females from Buea (4°09’247”N, 9°18’567”E), 8 males and 12 females from Kumba (4°39’101”N, 9°24’502”E), 16 males and 10 females from Tombel (4°45’359”N, 9°40’215”E), 2 males and 1 female from Djawara (4°02’24’’N, 10°05’60’’E), and 10 males and 14 females from Ekité (3°48’2.84’’N, 10°06’11.95’’E); deposited in the Zoology Laboratory, of University of Yaoundé 1, Cameroon ( ZLUYC) and in the Zoology Research Unit , Laboratory of Biology and Physiology of Animal Organisms, University of Douala, Cameroon (ZRULBPAOUDC) .

Diagnosis: lophi with almost flattened posterior margin; interlophal space with a complex structure shape; outer margins of lateral plates almost straight; apodemes of cingulum parallel, exceeded the apex of basal valves of penis, with U-shaped structure; valves of cingulum exceeded significantly the apex of apical valves of penis in lateral view; rami slightly opened in ventral view; hind wing hyaline, sometimes with red base and infumate tips; hind tibiae black in basal half, with one yellow basal ring framed by two black rings, reminder bright red in apical part, spines yellowish in basal half and blackish in apical half.

Description: male: length of body 22.00 ± 1.40 mm (n = 5 individuals), female: length of body 40.10 ± 3.80 mm (n = 5 individuals). Integument slightly rugose; head subconical; fastigial foveolae present; medium and slightly ridged eyes; fastigium of vertex short, with truncated apex and weak median carinulae; antenna filiform, longer than head and pronotum together; pronotum slightly tectiform, with weak lateral carinae in the prozona, obliterated and divergent in metazona; median carina raised and crossed by three sulcus, with an obtuse and weakly incised posterior margin; prozona longer than metazona; tegmina and wings fully developed, with rounded apex; intercalary vein of medial area of elytra present; tympanum present; prosternal process cylindrical; mesosternal interspace open, wider than its length; male supra-anal plate conical, with a transverse sulcus on the middle field and another on the apical field; male cercus longer in basal part and flattened, curved downwards in apical part (fig. 2b); male subgenital plate conical; posterior margin of subgenital plate in female protruding; valves of ovipositor robust, with curved apical. Bridge of epiphallus broad and arched; ancorae well developed, curved and with acute apex; lophi broads, lobiform and slightly curved upward (fig. 3Ia), posterior margin almost flattened in profile view; interlophal space forming a complex structure; external margins of the lateral plates almost straight; rami of cingulum well developed and broad; apodemes of cingulum slender, parallel with U-shaped structure, and exceeding the apex of basal valves of penis; zygoma large; basal and apical valves of penis connected by sclerotized flexion; lateral expansions of basal valves of penis strongly curved; apex of apical valves significantly curved upwards; valves of cingulum exceeding significantly the apex of apical valves of penis (fig. 3Id, 3Ig and 3Ij).

Coloration (fig. 2a): body generally greenish or yellowish; upper side of antennae clear, lower side dark. Posterior margin of eyes yellow highlighted. Pronotum disc with a broad brown longitudinal band bordered by two narrower yellow bands, the latter extending anteriorly to the fastigium and posteriorly on the elytra; hind wings hyalines, sometimes with red base and infumate tips; medio-internal area of hind femurs bearing two large black bands; infero-internal area and pre-genicular ring yellow; hind tibiae with a yellow basal ring framed by two black rings, remainder bright red; spines yellow in basal part and black in apical part (fig. 2 a).

Ecology: regardless of the study area, only one annual generation of nymphs and adults was observed. In the South-West area, the nymphs are present in April , June , July and from September to December. Adults are present throughout the year (fig. 4a). In the West zone, the nymphs are present in December while the adults are present from January to June (fig. 4b). In the Littoral zone, adults are present almost throughout the year, except in January and December. They are most abundant in September. Nymphs are present in April , September and November ( Fig. 4c ). In the Centre area , the nymphs are present in February , March , May , July , October and November. Adults are present in January and from March to December , with high abundances in June (fig. 4d). This species is widely distributed in the southern part of Cameroon. It can easily be observed in high abundance in fallows, crops fields, and agro-forests while it is accidentally found in the forests except those of Buea and Tombel (fig. 5a). Heteracris guineensis is an accidental species regardless of the vegetation type. Table 2 below shows the occurrence frequency obtained in each vegetation type in the different regions .

Figures

FIGURE 4: Temporal fluctuations of Heteracris guineensis in different study sites of Cameroon between August 2015 to August 2016 in the Littoral region and between February 2016 to January 2018 in the South-west, West, and Centre region. Legend: a: South-West region, b: West region, c: Centre region, d: Littoral region, ACR: Adults of Centre Region, NCR: Nymphs of Centre Region, AWR: Adults of West Region, NWR: Nymphs of West Region, ASWR: Adults of South-West Region, NSWR: Nymphs of South-West Region, ALR: Adults of Littoral region, NLR: Nymphs of Littoral region.