Description of Corymbus Park, gen. n. with six new species from the Afrotropical Region (Lepidoptera: Lecithoceridae)

The new genus Corymbus Park, gen. n., including six new species from the Afrotropical Region - Kenya, Malawi, Tanzania, and Uganda - is described. The new species are: C. deprinsi Park & Aarvik, sp. n., C. malmoius Park & Aarvik, sp. n., C . hirtitibia Park & Aarvik, sp. n., C . kenyaensis Park & Aarvik, sp. n., C . hallicis Park & Aarvik, sp. n., and C . nigrizosterus Park & Aarvik, sp. n. Corymbus crossogramma (Meyrick,1921), comb. n. is transferred from the genus Eridachtha Meyrick, 1910 to Corymbus Park. The venation of the type species, and adults and male genitalia of the new species are illustrated. A key to the species is provided.


Introduction
The fauna of Microlepidoptera in general and of the family Lecithoceridae in particular in the Afrotropical Region (= Ethiopian Region) have been poorly documented. The first known species of Lecithoceridae from the Afrotropical Region is Idiopteryx obliquella (Walsingham, 1881) and followed by Lecithocera flavipalpis Walsingham, 1891. Later JANSE (1954, 1963 treated 22 species of Lecithoceridae. VÁRI et al. (2002) listed 21 species of the family for the fauna of southern Africa. The taxonomic history and status of the family in the Afrotropical Region were summarized by . In the website "www.afromoths.net" compiled by J. & W. DE PRINS (updated 25 April 2019), 133 species belonging to 22 genera of the family are listed. In the website, ten recently described species belonging to the subfamily Lecithocerinae from Cameroon by PARK (2018a), seven species of the subfamily Torodorinae and eight new species of the genus Ptilothyris Walsingham, 1897 described by PARK (PARK, 2018b; are included. The genus Corymbus Park, gen. n. (Lecithoceridae: Lecithocerinae) is related to Notioseus Park, basal 2/3, R 5 to termen, M 1 remote from R 4+5 at base, nearly parallel to R 4+5 , M 2 and M 3 free, CuA 1 and CuA 2 free, A1+A2 forked at base. Hindwing yellowish white to orange white; venation with Sc and M 1 stalked for about half of their length; M 2 absent; M 3 and CuA 1 stalked. Male genitalia: Similar to those of Lecithocera Herrich-Schäffer, 1853 and Eridachtha Meyrick, 1910. Basal lobes of uncus semiovate, usually directed distally or outwardly. Gnathos with sclerotized, broad basal plate; median process narrowed toward apex, curved downward from beyond 2/3, pointed apically. Costal bar well developed. Tegumen broad, weakly sclerotized. Valva elongate; cucullus thumb like with rounded apex; ventral margin with a small triangular process or instead slightly protruded medially. Juxta usually with slender, weakly sclerotized latero caudal lobes. Aedeagus stout, curved medially, often with apical spines on dorsal surface, no cornuti.
Etymology: The generic name is derived from Latin, corymb or Greek, κο Ñ ρυµβος (= cluster), referring to the cluster of long hair like scales on the 2 nd segment of the labial palpus.
Key to the species of the genus Corymbus Park (due to the missing hind wing C. crossogramma (Meyrick, 1921) is not included in the key) Head: Vertex covered with orange white scales. Antenna slightly longer than forewing; basal segment elongate, slightly dilated toward apex, orange white; flagellum orange white, filiform, not ciliate. Second segment of labial palpus with long, hair like orange white scales above; 3 rd segment shorter than 2 nd segment, strongly upturned, orange white to pale orange, pointed apically. Thorax orange white to pale orange; tegulae of same colour, with fuscous scales along anterior margin. Hind tibia densely haired, fuscous grey on outer surface. Forewing ground colour orange white, brownish scales scattered irregularly, more dense beneath costa and in distal region; a round fuscous discal spot in middle and a kidney shaped one near end of cell; costa slightly arched; apex more or less acute; termen oblique; venation ( Abdomen yellowish brown on dorsal surface; tergites lack spinose zones; segment VII with sclerotized ridge on anterior margin (Fig. 2F).
Male genitalia (Figs 2C-E): Basal lobes of uncus semi ovate, directed outwardly, convex medially on caudal margin. Gnathos with heavily sclerotized basal plate; median process slender, curved downward beyond middle. Costal bar banded, arising from base of tegumen and reaching middle of valva, without distinctly acute median angle. Valva broad in basal 1/4, then narrowed; costa deeply concave medially; cucullus elongate, more or less thumb like with round apex, densely setose, with broad scales along apical margin; a small, triangular process near lower corner of cucullus, followed by small pegs along ventral margin towards apex; sacculus broad, terminated with round apex, shorter than 1/2 the length of basal part of valva. Juxta weakly sclerotized; latero caudal process slender, directed outwardly, slightly shorter than length of juxta; anterior margin broadly convex. Vinculum broad, with round apices; outer margin sclerotized, banded. Aedeagus thick, as long as valva, curved medially, with pair of small triangular spines subapically on dorsal margin. Female unknown.
Diagnosis: The new species is similar to the following new species, C. malmoius but it can be distinguished by more oblique termen of the forewing, fringes concolourous with weak median brownish band. In C. malmoius, the fringes are dark brown in distal half; and the valva of the male genitalia has a small, sharply acute, triangular process apically near the lower corner on ventral margin of cucullus, whereas C. malmoius does not have such a sharply pointed triangular process, but has a rounded protrusion on the ventral margin.
Distribution: Kenya (Central). Etymology: The species is named in honour of Willy De Prins who gave a remarkable contribution to studies on African moths, compiling the Afromoths website. Description Adult (Fig. 3A, B): Male wingspan 14-16 mm. Head, vertex orange white, with orange white,(comma not needed) erect scales laterally; frons orange white. Antenna longer than forewing; basal segment orange white, slightly dilated toward apex, without pecten; flagellum filiform, orange white throughout, not ciliate. Second segment of labial palpus densely covered with long, orange white hair like scales above, ventral surface more less smooth; 3 rd segment shorter than 2 nd segment, upturned, orange white, pointed apically. Thorax orange white; tegulae of same colour with fuscous scales along anterior margin. Hind tibia with dense hair like scales above and beneath, orange white mixed with grey scales. Forewing ground colour pale orange, densely and irregularly scattered with brownish scales, more dense in upper part of cell and distal 2/5; a distinct round, fuscous discal spot in middle and a kidney shaped one near end of cell; costa slightly arched in basal half and beyond 2/3; apex more or less acute; termen oblique, slightly sinuate medially; fringe shining white in basal 1/3, then black beyond; venation as C. deprinsi sp. n. Hindwing orange white; venation as in C. deprinsi sp. n. Abdomen yellowish brown on dorsal surface, lacking spinose zones on tergites; segment VII with sclerotized ridge on anterior margin. (Fig. 3G).

Corymbus malmoius
Male genitalia (Figs 3C-F): Basal lobes of uncus semiovate, directed outwardly, emarginated in Vshape medially on caudal margin. Gnathos with heavily sclerotized basal plate; median process slender, curved downward beyond 2/3. Tegumen posteriorly deeply emarginated in V-shape. Costal bar banded, curved downward at middle, not sharply angled medially. Valva extremely broad in basal 1/4, then abruptly narrowed; costa deeply concave medially; cucullus elongate, thumb like, densely setose, strongly convex on dorsal margin, with broad scales along apical margin; ventral margin with abroad protrusion at lower corner, followed by numerous pegs along margin towards apex; sacculus broad, terminated with round apex, about 1/4 length of ventral margin of valva. Juxta with slender latero caudal processes, shorter than the length of juxta; caudal margin concave medially and anterior margin medially with triangular process. Vinculum broad, rounded apically; outer margin narrowly sclerotized. Aedeagus stout, as long as valva, strongly curved medially, with pair of small triangular processes subapically on dorsal margin.
Diagnosis: This new species is similar to the preceding new species, C. deprinsi sp. n. in external and genital characters, but the forewing ground colour is more yellowish brown with more distinct discal spots, and the termen is less oblique. The male genitalia can be distinguished by the more elongate cucullus, remarkably convex on dorsal margin, ventral margin protruded at lower corner of cucullus. Different from C. deprinsi sp. n. which has a triangular process pointing apically.
Distribution: Tanzania (North), Kenya (South-East). Etymology: The species epithet is derived from a Korean archaic word, malmoye, meaning a language dictionary. Description Adult (Figs 4A-D): Male wingspan 11-11.5 mm. Head, vertex orange white, with pale orange erect scales laterally; frons orange white. Antenna about 1.2 times longer than forewing; basal segment orange white, slightly dilated toward apex, without pecten; flagellum filiform, orange white throughout, not ciliate. Second segment of labial palpus strongly angled, upturned, densely covered with pale orange, long hair like scales above; ventral surface yellowish white, more or less smooth; 3 rd segment slightly shorter than 2 nd segment, pale orange, pointed apically. Thorax orange white; tegulae of same colour, mixed with fuscous scales along anterior margin. Hind tibia with rough yellowish brown scales above and beneath. Forewing ground colour light orange or orange white, uniformly speckled with brownish scales; discal spots weakly developed, a small one in middle and a kidney shaped one near end of cell; costa slightly arched in basal 1/3, with some fuscous scales along costal margin in basal 2/5 and yellowish white scales beyond in apical 4/5; apex obtuse; termen oblique; fringe on termen concolorous in basal 1/3, with narrow orange white band medially, fuscous in apical half. Hindwing orange white; apex acute; fringes concolorous.

Corymbus hirtitibia
Male genitalia (Figs 4E-H): Basal lobes of uncus semiovate, directed outwardly, emarginated medially on caudal margin. Gnathos with heavily sclerotized basal plate; median process slender, curved downward beyond 2/3. Tegumen posteriorly deeply emarginated in V-shape. Costal bar banded, not sharply angled medially. Valva broad in basal 1/4; costa deeply concave medially; cucullus elongate, thumb like, densely setose, slightly convex on costal margin; ventral margin apically near lower corner with sharply pointed triangular process, followed by numerous pegs along margin; sacculus more or less slender with round apex, about half the length of basal part of valva. Juxta shield shaped with protrusions medially on lateral margins; latero caudal lobes directed distally; caudal margin concave medially and anterior margin triangularly produced. Vinculum broad, rounded apically, narrowly sclerotized along outer margin. Aedeagus stout, as long as valva, strongly curved medially, with a pair of small triangular processes subapically on dorsal margin.
Diagnosis: The new species can be distinguished from the above two species by the light orange forewing ground colour, the lack of distinct fuscous discal spots, the pale yellow hindwing, and the hind tibia with rough yellowish brown scales above and beneath. The male genitalia are similar to those of C. deprinsi sp. n., but it can be distinguished by the longer gnathos, the larger and more apically DESCRIPTION OF CORYMBUS PARK, GEN. N. WITH SIX NEW SPECIES FROM THE AFROTROPICAL REGION acute ventral process on the cucullus, and the larger juxta with latero caudal lobes directed distally, whereas they are directed outwardly in C. deprinsi sp. n.
Distribution: Tanzania (South), Kenya (Central). Etymology: The species epithet is derived from Latin, hirtus (= hairy) and tibia (= leg), referring to the hairy hind tibia. Description Adult (Figs 5A-B): Male wingspan, 14 mm. Head, vertex yellowish white, with orange white erect scales laterally. Antenna slightly longer than forewing; basal segment orange white, dilated in distal half, without pecten; flagellum filiform, orange white, not ciliate. Second segment strongly angled, upturned, densely covered with pale orange, long, hair like scales above, smooth on ventral surface; 3 rd segment slightly shorter than 2 nd segment, pale orange, pointed apically. Thorax yellowish white; tegulae of same colour as thorax, fuscous along anterior margin. Hind tibia with rough yellowish brown scales above and beneath; tarsi yellowish white. Forewing ground colour yellowish white, speckled with brownish scales, more dense in upper 1/3 and in distal 2/5; discal spots weak, a small one in middle and a kidney shaped one near end of cell; costa slightly arched in basal half, with some fuscous scales along costal margin in basal 1/3; apex obtuse; termen oblique; fringe on termen concolorous in basal half and fuscous in apical half. Hindwing orange white; apex acute; fringes concolorous. Abdomen dorsally orange white, lacking spinose zones on tergites; segment VII with sclerotized ridge on anterior margin; sternite VIII broad, concave medially on caudal margin (Fig. 5E).
Diagnosis: The male genitalia of C. kenyaensis sp. n. are similar to those of C. hirtitibia sp. n., but the basal lobes of the uncus are more deeply incised on the caudal margin; the cucullus is more dilated distally, with a ventral process slightly longer but not sharply pointed apically; the latero caudal lobes of the juxta directed outwardly; and the aedeagusus with minute processes subapically. However, it is easily distinguished from C. hirtitibia sp. n. by the yellowish white ground colour of both wings.
Distribution: Kenya (Central). Etymology: The species epithet is derived from the type locality. Head, vertex pale greyish orange, laterally with yellowish brown erect scales. Antenna slightly longer than forewing; basal segment dark brown in basal 3/5 on external surface, slightly dilated in apical 1/3, without pecten; flagellum filiform, pale orange becoming orange white towards apex, not ciliate. First segment of labial palpus dark brown externally; second segment strongly angled, arched, upturned, densely covered with pale orange, long, hair like scales above, smooth on ventral surface; 3 rd segment shorter than 2 nd segment, pale orange, pointed apically. Thorax covered with brownish scales dorsally; tegulae of same colour as thorax, fuscous along anterior margin. Hind tibia with rough orange white hair like scales above and beneath; tarsi orange white. Forewing ground colour orange white, irregularly speckled with dark brown scales; a round, small dark brown discal spot in middle and a kidney shaped, dark brown oblique one near end of cell; costa slightly arched in basal half, nearly straight beyond; apex obtuse; termen oblique; fringe on termen pale orange grey. Hindwing ground colour orange white; a row of erect scales running from base along lower margin of cell; a row of black scales centrally from base to termen, around tornus, and along termen; apex acute; fringes concolorous. Abdominal segments lacking spinose zones on tergites; sternite VIII concave on caudal margin medially (Fig. 6F).

Corymbus hallicis
Male genitalia (Figs 6D-E): Basal lobes of uncus semiovate, directed outwardly emarginated medially on caudal margin. Basal plate of gnathos sclerotized latero caudally with triangular acute processes; median process slender, curved downward preapically. Tegumen posteriorly deeply emarginated in V-shape. Costal bar slender, gently curved, without median angle. Valva broad basally, with a great toe like process on the ventral margin of basal part; costa gently concave medially; cucullus thumb like, densely setose, with slightly convex costal margin, with numerous pegs along ventral margin; sacculus shorter than basal part of valva, nearly parallel sided, slightly oblique near apex. Juxta slender latero caudal lobes as long as the length of juxta; caudal margin medially deeply concave. Vinculum broad, rounded apically, with narrowly sclerotized band along outer margin. Aedeagus stout, shorter than valva, curved medially; with pair of large triangular processes apically on dorsal margin.
Diagnosis: The new species can be distinguished from its congeners by the more fuscous forewing and the hindwing with blackish scales in central part, around tornus, and along termen. The male genitalia have more easily distinguishable diagnostic characters with a great toe like process on the basal part of the valva, not on cucullus, and the aedeagus has a pair of large triangular processes on ventral margin basally.
Distribution: Malawi (Central). Etymology: The species epithet is derived from Latin, hallex (= great toe, hallux) referring to the toe like process on the ventral margin of the valva. Description Adult (Figs 7A-C, G): Male wingspan 14-14.5 mm. Head vertex orange white, laterally with orange white erect scales. Antenna about 1.2 times longer than forewing length; basal segment yellowish white, without pecten; flagellum filiform, yellowish white, not ciliate. Second segment of labial palpus nearly straight in basal 1/3, then bent at right angle, upturned, densely covered with orange white, long hair like scales appressed above, nearly smooth on ventral surface; 3 rd segment much shorter than 2 nd segment, orange white, pointed apically. Thorax and tegulae orange white. Hind tibia with rough orange white hair like scales above and beneath; tarsi yellowish white. Forewing ground colour yellowish white, scattered with pale orange scales in basal 1/3; discal spots weak, one smaller in middle and a kidney shaped one near end of cell; costa slightly arched beyond 2/3; apex obtuse; termen oblique; fringes on termen concolorous in basal half and fuscous in apical half. Hindwing orange white, with a black, club shaped streak arising from middle of cell to near termen; apex more or less obtuse; fringes concolorous. Abdomen orange white dorsally, lacking spinose zones on tergites; segment VII with sclerotized ridge on anterior margin; sternite VIII broad, concave medially on caudal margin. (Fig. 7G).

Corymbus nigrizosterus
Male genitalia (Figs 7D-F): Basal lobes of uncus large, broad, with more or less dentate caudal DESCRIPTION OF CORYMBUS PARK, GEN. N. WITH SIX NEW SPECIES FROM THE AFROTROPICAL REGION margin medially; the median process of the gnathos relatively short; posterior margins of tegumen with distinct oblique, V-shape ridges; ventral process at the lower corner of the cucullus triangular with broader base; cucullus apically nearly forming a right angle; juxta with thick latero caudal lobes, directed caudally. Aedeagus stout, broader in basal 1/3, strongly curved medially, with pair of apical triangular processes on dorsal surface. Diagnosis: The new species can be distinguished from all congeners by the presence of a black, club shaped streak in the hindwing, running from near middle to near termen. The male genitalia are similar to those of C. kenyaensis sp. n., but can be distinguished by the large, broad basal lobes of the uncus, which are more or less dentate medially on the caudal margin; the shorter median process of the gnathos; the tegumen with distinct V-shaped, oblique ridges on posterior margin; triangular process with broader base at the lower corner of the cucullus; and the latero caudal lobes of the juxta thicker.
Distribution: Tanzania (East: Tanga region), Uganda. Etymology: The species name is derived from Latin, niger (= black), referring to the conspicuous black streak in the hindwing.
Corymbus crossogramma (Meyrick, 1921) comb. n. (Fig. 1B) Corthyntis crossogramma Meyrick, 1921: 87. Eridachtha crossogramma;Meyrick, 1925: 220;Janse, 1954: fig. 10-line drawing). Remarks: The forewing veins CuA 1 and CuA 2 of crossogramma are remote from each other, differing from those of Eridachtha in which they are stalked. It is assumed that MEYRICK (1925) placed crossogramma in Eridachtha due to a miss interpretation of CuA 1 and CuA 2 , which are shortly stalked in the forewing, and JANSE (1954) followed it. Also the expansible tuft of hairs on the 2 nd segment of the labial palpus in crossogramma differs from that of Eridachtha, forming a cluster of long hair like scales. Consequently, crossogramma is transferred to Corymbus Park. The species can be distinguished from the new species described above by the external appearance as figured in figure1B.