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''Helcita'' is a small genus of planthoppers from the family Derbidae, tribe Zoraidini, currently (2024) with only 4 species. All of the species are uncommon. They have rather restricted and widely separated distribution ranges. Two species are found in tropical parts of Africa, one in Sri Lanka and southern India, and one in Taiwan and some neighbouring islands of Japan. The species of ''Helcita'' can be distinguished from other similar genera by a combination of features related to the venation of the forewings and the shape of the head. On the forewing, the media vein has 6 branches with the 3rd branch forking further into 2 sub branches. This venation is similar to that of the genus ''Pamendanga'' from which ''Helcita'' species can be distinguished by the profile of the head. In ''Helcita'' species, the head extends conically in front of the eyes, whereas ''Pamendanga'' species have a flat profile.
Type species: ''Derbe wahlbergi'' Stål, 1855, a synonym of ''Helcita wahlbergi''
The 4 species of Helcita are all uncommon and have few distribution records. Their ranges are clearly separated, with none of the distributions overlapping. The type species, ''Helcita wahlbergi'' was described from "terra Natalensi", a part of South Africa now known as the KwaZulu-Natal Province. In that region, ''H. wahlbergi'' has been mainly reported from coastal areas, around the city of Durban and further north along the coast, almost up to the border with Mozambique.
In 1926, Frederick Arthur Godfrey Muir, Muir reported ''H. wahlbergi'' also from Sierra Leone, providing a description and illustration. However, 2 years later he realized that this report was based on a misidentification and he renamed the species in Sierra Leone to ''Helcita occidentalis''. ''H. occidentalis'' has been also reported from the Central African Republic and from 2 locations in the Democratic Republic of the Congo.
A third species, ''Helcita nitagalensis'', has been described from Nitagala in Sri Lanka, originally under the name ''Derbe nitagalensis''. That species has been also reported in south-eastern parts of India. A fourth species, ''Helcita shirakii'', has been described from Taiwan. That species is also listed as part of the fauna of the Ryukyu Islands in southern Japan.
The species of ''Helcita'' show similarities to those in the genus ''Pamendanga''. However, in ''Pamendanga'' species the head has a flat profile, while in ''Helcita'' the head is conically extended in front of the eyes, when seen from the side. On the forewing, ''Helcita'' species have a media vein with 6 branches, and the third branch splits again into two sub branches. The radius has 3 branches near its tip. The hind wing of ''Helcita'' species is about half as long as the forewing and usually longer compared to those of ''Pamendanga'' species. Like many other species of Zoraidini, resting ''Helcita'' species raise their wings above the body and spread them out at an angle of about 60°.
The upper side of the head between the eyes (the vertex) can be rather wide like in ''Helcita shirakii'' or narrow like in ''Helcita nitagalensis''. In ''Helcita wahlbergi'' and ''H. occidentalis'' the width of the vertex is in between these two extremes, but is still wider compared to most species of ''Pamendanga'' where the vertex is usually narrow and triangular. In frontal view, the upper part of the face of ''Helcita'' species can also be wide, corresponding to the width of the vertex. However, in those cases, the face is narrower between the eyes. The antennae of ''Helcita'' species are elongated, but shorter than the face, whereas in ''Pamendaga'' species they are about as long as the face.
''Helcita'' species have a body size of around 4 mm and a forewing length of around 10 mm. The general colour is brownish to ochrous, with the ridges on the head and the mesonotum being whitish yellow. The forewings are typically brownish with transparent patches or transparent with brown patches. The veins are whitish to yellowish. Some species, like ''Helcita wahlbergi'', seem to have a variable colouration, ranging from whitish to brownish. The individual ''Helcita'' species can be distinguished by their colouration and the structures of the male genitalia.
The description of the genus ''Helcita'' by Carl Stål, Stål in 1856 was based on a South African species which Stål had described a year earlier as ''Derbe wahlbergi''. The very short descriptions by Stål of both the type species and the genus were expanded by subsequent authors, who provided distinguishing characters to similar genera in the tribe Zoraidini, like ''Pamendanga''. In 1906, William Lucas Distant, Distant described the genus ''Jada'', based on a species from Sri Lanka which had been described in 1891 by William Forsell Kirby, Kirby as "''Derbe'' (?) ''nitagalensis''". However, the genus ''Jada'' was subsequently regarded to be a synonym of ''Helcita'' by Frederick Arthur Godfrey Muir, Muir. In 1910, another species of ''Jada'', ''Jada maculipennis'', was described by Charles S. Banks from the Philippine island of Palawan. However, that species is now regarded as belonging to the genus ''Pamendanga''.
''Thracia nitagalensis'' (Kirby, 1891)
''Jada nitagalensis'' (Kirby, 1891)
''Helcita nitagalensis'' (Kirby, 1891)
This species has been named after the type locality, Nitagala in Sri Lanka. Apart from Sri Lanka, it has been also reported from south-eastern India. The colouration is described by William Lucas Distant, Distant as "Tawny-yellow; vertex of head, thoracic carinations, and face nearly pure white; apices of tarsi black; tegmina pale tawny-brown, the veins yellow ...".
''Helcita occidentalis'' Muir, 1928
In 1926, Frederick Arthur Godfrey Muir, Muir described and illustrated a species from Sierra Leone which he wrote agrees quite well with Stål's ''Helcita wahlbergi'' except for darker marks on the forewings. He would need to examine a male from South Africa (the type locality of ''H. wahlbergi'') to confirm this identification. In 1928, after having examined a male from Durban, South Africa, he wrote that the specimens from Sierra Leone and South Africa belong to different species, and he renamed the Sierra Leone species as ''Helcita occidentalis''. There are few records of ''H. occidentalis'', but the distribution seems to extend from Sierra Leone to the Central African Republique and to the northern and western parts of the Democratic Republic of the Congo. The colouration has been described as ochrous brown with some parts darker, the lower parts and the sides are lighter and the pronotum is yellowish white. The forewings are translucent with many brown patches, especially in the costal area and at the tips of the veins. The fore and middle femurs are dark brown in front and the fore and middle tibiae as well as the tarsi are brown. The hind tibiae are yellowish with brown tips.
This species has been described from Taiwan, but is also reported from the Ryukyu Islands in southern Japan. The general colour has been described as brown with yellowish brown spots on pronotum and abdomen. The ridges on head and mesonotum are light yellowish. The forewings are brownish, interrupted by lighter areas.
''Helcita wahlbergi'' (Stål, 1855)
This is the type species of the genus ''Helcita''. It is found in South Africa, around the city of Durban. The colouration has been described as yellowish. The forewings are whitish with brown patches.
Distribution
The 4 species of Helcita are all uncommon and have few distribution records. Their ranges are clearly separated, with none of the distributions overlapping. The type species, ''Helcita wahlbergi'' was described from "terra Natalensi", a part of South Africa now known as the KwaZulu-Natal Province. In that region, ''H. wahlbergi'' has been mainly reported from coastal areas, around the city of Durban and further north along the coast, almost up to the border with Mozambique.
In 1926, Frederick Arthur Godfrey Muir, Muir reported ''H. wahlbergi'' also from Sierra Leone, providing a description and illustration. However, 2 years later he realized that this report was based on a misidentification and he renamed the species in Sierra Leone to ''Helcita occidentalis''. ''H. occidentalis'' has been also reported from the Central African Republic and from 2 locations in the Democratic Republic of the Congo.
A third species, ''Helcita nitagalensis'', has been described from Nitagala in Sri Lanka, originally under the name ''Derbe nitagalensis''. That species has been also reported in south-eastern parts of India. A fourth species, ''Helcita shirakii'', has been described from Taiwan. That species is also listed as part of the fauna of the Ryukyu Islands in southern Japan.
Description
The species of ''Helcita'' show similarities to those in the genus ''Pamendanga''. However, in ''Pamendanga'' species the head has a flat profile, while in ''Helcita'' the head is conically extended in front of the eyes, when seen from the side. On the forewing, ''Helcita'' species have a media vein with 6 branches, and the third branch splits again into two sub branches. The radius has 3 branches near its tip. The hind wing of ''Helcita'' species is about half as long as the forewing and usually longer compared to those of ''Pamendanga'' species. Like many other species of Zoraidini, resting ''Helcita'' species raise their wings above the body and spread them out at an angle of about 60°.
The upper side of the head between the eyes (the vertex) can be rather wide like in ''Helcita shirakii'' or narrow like in ''Helcita nitagalensis''. In ''Helcita wahlbergi'' and ''H. occidentalis'' the width of the vertex is in between these two extremes, but is still wider compared to most species of ''Pamendanga'' where the vertex is usually narrow and triangular. In frontal view, the upper part of the face of ''Helcita'' species can also be wide, corresponding to the width of the vertex. However, in those cases, the face is narrower between the eyes. The antennae of ''Helcita'' species are elongated, but shorter than the face, whereas in ''Pamendaga'' species they are about as long as the face.
''Helcita'' species have a body size of around 4 mm and a forewing length of around 10 mm. The general colour is brownish to ochrous, with the ridges on the head and the mesonotum being whitish yellow. The forewings are typically brownish with transparent patches or transparent with brown patches. The veins are whitish to yellowish. Some species, like ''Helcita wahlbergi'', seem to have a variable colouration, ranging from whitish to brownish. The individual ''Helcita'' species can be distinguished by their colouration and the structures of the male genitalia.
Biology
There is no information on the biology of the immature stages of ''Helcita'' species. However, it can be assumed that they live in decaying organic matter like other derbids, feeding on fungi. There are few host plant records for the adult hoppers in the genus ''Helcita''. In other members of the tribe Zoraidini, the adults feed mainly on monocots. Images of ''Helcita wahlbergi'' also suggest they feed on monocots, but ''Helcita occidentalis'' has been reported from both Elaeis, oil palms (a monocot) and from Theobroma cacao, cacao trees (not a monocot).Taxonomy and species
The description of the genus ''Helcita'' by Carl Stål, Stål in 1856 was based on a South African species which Stål had described a year earlier as ''Derbe wahlbergi''. The very short descriptions by Stål of both the type species and the genus were expanded by subsequent authors, who provided distinguishing characters to similar genera in the tribe Zoraidini, like ''Pamendanga''. In 1906, William Lucas Distant, Distant described the genus ''Jada'', based on a species from Sri Lanka which had been described in 1891 by William Forsell Kirby, Kirby as "''Derbe'' (?) ''nitagalensis''". However, the genus ''Jada'' was subsequently regarded to be a synonym of ''Helcita'' by Frederick Arthur Godfrey Muir, Muir. In 1910, another species of ''Jada'', ''Jada maculipennis'', was described by Charles S. Banks from the Philippine island of Palawan. However, that species is now regarded as belonging to the genus ''Pamendanga''.
''Helcita nitagalensis''
''Derbe'' (?) ''nitagalensis'' Kirby, 1891''Thracia nitagalensis'' (Kirby, 1891)
''Jada nitagalensis'' (Kirby, 1891)
''Helcita nitagalensis'' (Kirby, 1891)
This species has been named after the type locality, Nitagala in Sri Lanka. Apart from Sri Lanka, it has been also reported from south-eastern India. The colouration is described by William Lucas Distant, Distant as "Tawny-yellow; vertex of head, thoracic carinations, and face nearly pure white; apices of tarsi black; tegmina pale tawny-brown, the veins yellow ...".
''Helcita occidentalis''
''Helcita wahlbergi'' Muir, 1926 [not Stål]''Helcita occidentalis'' Muir, 1928
In 1926, Frederick Arthur Godfrey Muir, Muir described and illustrated a species from Sierra Leone which he wrote agrees quite well with Stål's ''Helcita wahlbergi'' except for darker marks on the forewings. He would need to examine a male from South Africa (the type locality of ''H. wahlbergi'') to confirm this identification. In 1928, after having examined a male from Durban, South Africa, he wrote that the specimens from Sierra Leone and South Africa belong to different species, and he renamed the Sierra Leone species as ''Helcita occidentalis''. There are few records of ''H. occidentalis'', but the distribution seems to extend from Sierra Leone to the Central African Republique and to the northern and western parts of the Democratic Republic of the Congo. The colouration has been described as ochrous brown with some parts darker, the lower parts and the sides are lighter and the pronotum is yellowish white. The forewings are translucent with many brown patches, especially in the costal area and at the tips of the veins. The fore and middle femurs are dark brown in front and the fore and middle tibiae as well as the tarsi are brown. The hind tibiae are yellowish with brown tips.
''Helcita shirakii''
''Helcita shirakii'' Yang and Wu, 1993This species has been described from Taiwan, but is also reported from the Ryukyu Islands in southern Japan. The general colour has been described as brown with yellowish brown spots on pronotum and abdomen. The ridges on head and mesonotum are light yellowish. The forewings are brownish, interrupted by lighter areas.
''Helcita wahlbergi''
''Derbe wahlbergi'' Stål, 1855''Helcita wahlbergi'' (Stål, 1855)
This is the type species of the genus ''Helcita''. It is found in South Africa, around the city of Durban. The colouration has been described as yellowish. The forewings are whitish with brown patches.
References
{{Taxonbar, from1=Q10519438 Taxa described in 1856 Auchenorrhyncha genera Zoraidini Hemiptera of Africa Hemiptera of Asia Taxa named by Carl Stål