Four new species of the subgenus Minettiella from China (Diptera, Lauxaniidae, Minettia)

Abstract Four species of Minettia Robineau-Desvoidy, 1830 from Southwest China are described as new to science: Minettia (Minettiella) dashahensissp. nov., M. (Minettiella) longispinasp. nov., M. (Minettiella) membranaceasp. nov. and M. (Minettiella) zhaotongensissp. nov. A key to the species of the subgenus Minettiella of the world is presented.

It is controversial whether Minettiella is a subgenus or a genus. Shatalkin (1996) raised the subgenus Minettiella to the genus level because of the specialized male genitalia and other diagnosis of Minettiella elbergi Shatalkin, 1996. Lee andHan (2014) consider that the genus Minettiella can only be distinguished from the closely resembling genera by the combination of the yellow body coloration and single katepisternal seta, and also pointed out that these characters do not seem to justify their generic differentiation. Shi and Yang (2014) examined the male genitalia of some specimens from five subgenera of Minettia, found the diversity of the male genitalia in Minettiella was the same as that in the subgenera Minettia and Plesiominettia of genus Minettia, and rejected Shatalkin's elevation of the subgenus Minettiella to the genus level. We agree with Shi and Yang (2014) and insist that Minettiella is a subgenus of the genus Minettia.

Materials and methods
General terminology follows Cumming and Wood (2009) and Gaimari and Silva (2010). Genitalia preparations were made by removing and macerating the apical portion of the abdomen in cold saturated NaOH for six hours, then rinsing and neutralizing them for dissection and study. After examination in glycerin, they were transferred to fresh glycerin and stored in a microvial pinned below the specimen or moved to an ethanol tube together with the wet specimens. Specimens examined were deposited in the China Agricultural University, Beijing, China (CAUC).

Taxonomy
Key to the subgenera of Minettia and the species of the subgenus Minettiella * Face and parafacial with sparse whitish gray pruinescence; arista short plumose, longest rays slightly shorter than height of first flagellomere; mid femur with four anterior setae; male genitalia: epandrium with wide median incision on posterior margin in lateral view; surstylus short cone-shaped and originating from inner side of epandrium in lateral view and converging apically in posterior view; female unknown ............ Minettia (Minettiella) plurifurcata -Face with a yellow triangular median spot or only slightly yellow at middle of face, and parafacial with dense whitish gray pruinescence; arista with microscopic setulae, longest rays shorter than 1/3 height of first flagellomere; mid femur with three anterior setae; male genitalia: epandrium with small subapical incision in lateral view and acute apically in posterior view, surstylus contorted with apical setulae and originating from inner side of epandrium in lateral view; female sternite eight semicircular with pair of processes on anterior margin and a wide groove between processes . Diagnosis. Arista blackish brown except paler basally. Mesonotum 1 + 3 dorsocentral setae, acrostichal setulae in four irregular rows, with two pairs of strong acrostichal setulae before prescutellar setae. Epandrium broad, ventral apical angle with setae. Surstylus separated from epandrium and extended from interior of epandrium, curved in lateral view, with connective sclerite under cercus in posterior view. Aedeagal apodeme long, nearly as long as aedeagus.
Thorax (Fig. 4) black, with gray pruinescence. 1 + 3 dorsocentral setae, acrostichal setulae in four irregular rows, with two pairs of strong acrostichal setulae before prescutellar setae; a pair of prescutellar setae, shorter than anteriormost dorsocentral setae. One anepisternal seta and one katepisternal seta. Legs black, tibia brownish yellow at base, mid and hind tarsomeres dark yellow (sometimes fore tarsomeres also dark yellow). Fore femur with eight posterior dorsal setae and five posterior ventral setae; fore tibia with one dorsal preapical seta and one short apical ventral seta. Mid femur with three or four anterior setae and one short apical posterior seta; mid tibia with one strong dorsal preapical seta and one strong apical ventral seta. Hind femur with one preapical anterior dorsal seta; hind tibia with one weak dorsal preapical seta and one short apical ventral seta. Wing slight yellow and hyaline, pale yellow at base; costa with 2 nd (between R 1 and R 2+3 ), 3 rd (between R 2+3 and R 4+5 ), and 4 th (between R 4+5 and M 1 ) sections in proportion of 9.5 : 2.8 : 2.1; r-m on middle of discal cell; ultimate and penultimate sections of M 1 in proportion of 6.8 : 3.9; ultimate section of CuA 1 ca. 1/5 of penultimate. Haltere pale yellow. Abdomen (Fig. 5) black, with sparse gray pruinescence. Male genitalia (Figs 6-10): syntergosternite circular. Epandrium broad, ventral apical angle with setae. Surstylus separated from epandrium and extended from interior of epandrium, tapering apically, curved in lateral view, with connective sclerite under cercus in posterior view; hypandrium narrow in the middle and wide on both sides, with small inner process. Postgonite with setae, slender and curved apically in lateral view; aedeagus tubular, ventral sclerite V-shaped concave apically in ventral view, with a single long spiny process on the bottom, forming an acute angle with aedeagus, aedeagus with membranous processes internally; aedeagal apodeme as long as aedeagus.
Remarks. The new species is very similar to M. (Minettiella) sasakawai from China (Hainan) and Vietnam in the following characteristics: acrostichal setulae in four rows; mid and hind tarsomeres dark yellow, fore femur with eight posterior dorsal setae and five posterior ventral setae; wing slight yellow and hyaline, pale yellow at base; hypandrium narrow in the middle and wide on both sides, but it can be separated from the latter in the mesonotum with 1+3 dorsocentral setae, two pairs of strong acrostichal setulae present in front of prescutellar setae; the syntergosternite being circular; epandrium is broad. In M. (Minettiella) sasakawai, the mesonotum with 0 + 2 dorsocentral setae, a pair of strong acrostichal setulae present in front of prescutellar setae; the syntergosternite is semicircular and narrow under the spiracle; epandrium is slender.
Distribution. China (Guizhou). Diagnosis. Frons dark brown, anterior margin yellow, two black longitudinal stripes along fronto-orbital rows, extending from ocellar triangle to occiput. Arista blackish brown except paler basally, pubescent with longest setulae almost as long as 1/4 height of first flagellomere. Mesonotum with 0 + 2 dorsocentral setae, acrostichal setulae in six irregular rows. Surstylus separated from epandrium, distorted in lateral view and only one short curved claviform process, narrow apically and inwards curved in posterior view. Aedeagal apodeme long, nearly as long as aedeagus.
Head (Fig. 11) black. Face and parafacial with dense grayish white pruinescence. Frons dark brown, anterior margin yellow, as long as wide and parallel-sided, two black longitudinal stripes along fronto-orbital rows, extending from ocellar triangle to occiput; ocellar triangle black, ocellar setae developed, almost as long as posterior fronto-orbital setae and extending to anterior margin of frons; anterior fronto-orbital setae reclinate, shorter than posterior fronto-orbital setae. Gena ca. 1/6 height of eye. Antenna brownish yellow, first flagellomere blackish brown on 2/3 apex of dorsal margin, 1.7 times longer than high; arista blackish brown except paler basally, pubescent with longest setulae almost as long as 1/4 height of first flagellomere. Proboscis blackish brown, with pale yellow and black setulae; palpus black with black setulae.
Thorax (Fig. 14) black, with gray pruinescence. 0 + 2 dorsocentral setae, acrostichal setulae in six irregular rows, with pair of strong acrostichal setulae before prescutellar setae; a pair of prescutellar setae, almost as long as anteriormost dorsocentral setae. One anepisternal seta and one katepisternal seta. Legs black, tibia brownish yellow at base, mid and hind tarsomeres dark yellow (sometimes fore tarsomeres also dark yellow). Fore femur with eight posterior dorsal setae and five posterior ventral setae; fore tibia with one dorsal preapical seta and one short apical ventral seta. Mid femur with four anterior setae and one short apical posterior seta; mid tibia with one strong dorsal preapical seta and one strong apical ventral seta. Hind femur with one preapical anterior dorsal seta; hind tibia with one weak dorsal preapical seta and one short apical ventral seta. Wing slight yellow and hyaline, pale yellow at base; costa with 2 nd (between R 1 and R 2+3 ), 3 rd (between R 2+3 and R 4+5 ), and 4 th (between R 4+5 and M 1 ) sections in proportion of 7.1 : 2.0 : 1.5; r-m on middle of discal cell; ultimate and penultimate sections of M 1 in proportion of 4.9 : 2.8; ultimate section of CuA 1 ca. 1/6 of penultimate. Haltere pale yellow.
Abdomen (Figs. 15) black, with sparse gray pruinescence. Male genitalia : syntergosternite circular, with one broad membranous ventral process. Epandrium narrow dorsally and broad ventrally, with one small ventral concave basally, ventral setae apically. Surstylus separated from epandrium, distorted in lateral view and only saw one short curved claviform process, narrow apically and inwards curved in posterior view, with connective broad sclerite under cercus at base; hypandrium narrow, U-shaped, with one distinct membranous inner process. Postgonite slender in ventral view, acute at tip, as long as half-length of aedeagus; aedeagus with long spiny processes internally, with distinct apical concave; aedeagal apodeme long, nearly as long as aedeagus.
Remarks. The new species is very similar to Minettia (Minettiella) membranacea sp. nov. from Yunnan in the following characteristics: frons with two black longitudinal stripes along fronto-orbital rows, extending from ocellar triangle to occiput; mesonotum with 0 + 2 dorsocentral setae, acrostichal setulae in six irregular rows, and a pair of strong acrostichal setulae present in front of prescutellar setae; wing slight yellow and hyaline, pale yellow at base, but it can be separated from the latter in the fore femur with five posterior ventral setae, the mid femur with four anterior setae, the syntergosternite with one broad membranous process; the hypandrium narrow and U-shaped; the aedeagus with long spines ventrally. In M. (Minettiella) membranacea sp. nov., the fore femur with six posterior ventral setae, the mid femur with three anterior setae, the syntergosternite with one anterior median process in lateral view, one membranous band under ventral bridge; the hypandrium V-shaped; the aedeagus with membranous processes internally.
Distribution. China (Guizhou). Diagnosis. Antenna brownish yellow, first flagellomere blackish brown on 2/3 apex of dorsal margin. Proboscis blackish brown, with pale yellow and black setulae. Mesonotum with two dorsocentral setae, acrostichal setulae in six irregular rows. Mid and hind tibia brownish yellow at base and tarsomeres dark yellow. Syntergosternite circular, broad dorsally and narrow ventrally, with one small anterior median process in lateral view, one membranous band under ventral bridge. Hypandrium median ventral side outward, V-shaped. Aedeagal apodeme long, slightly shorter than aedeagus.
Head (Fig. 21) black. Face and parafacial with dense grayish white pruinescence. Frons dark brown, as long as wide and parallel-sided, two wide black longitudinal stripes along fronto-orbital rows, extending from ocellar triangle to occiput; ocellar triangle black, ocellar setae developed, almost as long as posterior fronto-orbital setae and extending to anterior margin of frons; anterior fronto-orbital setae reclinate, shorter than posterior fronto-orbital setae. Gena ca. 1/7 height of eye. Antenna brownish yellow, first flagellomere blackish brown on 2/3 of the apex of dorsal margin, 1.7 times longer than high; arista blackish brown except paler basally, pubescent with longest setula almost as long as 1/3 height of first flagellomere. Proboscis blackish brown, with pale yellow and black setulae; palpus black with black setulae. Thorax (Fig. 24) black, with brownish gray pruinescence. Two dorsocentral setae, acrostichal setulae in six irregular rows, with pair of strong acrostichal setulae before prescutellar setae; a pair of prescutellar setae, longer than anteriormost dorsocentral setae. One anepisternal seta and one katepisternal seta. Legs black, mid and hind tibia brownish yellow at base and tarsomeres dark yellow. Fore femur with eight posterior dorsal setae and six posterior ventral setae; fore tibia with one dorsal preapical seta and one short apical ventral seta. Mid femur with three anterior setae and one short apical posterior seta; mid tibia with one strong dorsal preapical seta and one strong apical ventral seta. Hind femur with one preapical anterior dorsal seta; hind tibia with one weak dorsal preapical seta and one short apical ventral seta. Wing slight yellow and hyaline, pale brown at base; costa with 2 nd (between R 1 and R 2+3 ), 3 rd (between R 2+3 and R 4+5 ), and 4 th (between R 4+5 and M 1 ) sections in proportion of 9.6 : 2.4 : 1.8; r-m before middle of discal cell; ultimate and penultimate sections of M 1 in proportion of 6.4 : 4.4; ultimate section of CuA 1 ca. 1/6 of penultimate. Haltere pale yellow.
Abdomen (Fig. 25) black, with sparse gray pruinescence. Male genitalia : syntergosternite circular, broad dorsally and narrow ventrally, with one small an- terior median process in lateral view, one membranous band under ventral bridge. Epandrium slender. Surstylus separated from epandrium, with setae and curved in lateral view, with connective sclerite under cercus in posterior view; hypandrium median ventral side outward, V-shaped. Postgonite curved apically in ventral view, with long setae and nearly digitiform, aedeagus with membranous processes internally, with small apical concave; aedeagal apodeme long, slightly shorter than aedeagus. Remarks. The new species is very similar to Minettia (Minettiella) spinosa Shi & Yang from Hubei in the following characteristics: acrostichal setulae in six rows; the tarsomeres dark yellow, mid femur with three anterior setae and one short apical posterior seta; wing slight yellow and hyaline, but it can be separated from the latter in the face without spot; the mesonotum with pair of strong acrostichal setulae; the syntergosternite without setula near spiracle; the epandrium without subapical concavity; the hypandrium V-shaped. In M. (Minettiella) spinosa, the face with a yellow triangular median spot or only slightly yellow in center of face; the mesonotum without strong acrostichal setulae; the syntergosternite with one setula near spiracle; the epandrium with one small subapical concavity; the hypandrium H-shaped.
Distribution. China (Yunnan). Diagnosis. Face and parafacial with dense grayish white pruinescence. Anterior fronto-orbital setae reclinate, shorter than posterior fronto-orbital setae. Mesonotum with 0+2 dorsocentral setae, acrostichal setulae in six irregular rows. Mid and hind tarsomeres dark yellow (sometimes fore tarsomeres also dark yellow). Wing slight yellow and hyaline, brown at base. Dorsal of epandrium narrower than dorsal of syntergosternite. Surstylus separated from epandrium, claviform, with single long seta in the middle, expanded apicially in lateral view and cone-shaped in posterior view. Postgonite hairy. Aedeagal apodeme tubular, as long as half-length of aedeagus.
Description. Male. Body length 3.9-4.2 mm, wing length 4.4-4.8 mm. Female. Body length 3.8-4.3 mm, wing length 4.3-4.9 mm. Head (Fig. 31) black. Face and parafacial with dense grayish white pruinescence. Frons dark brown, as long as wide and parallel-sided, two black longitudinal stripes along fronto-orbital rows, extending from ocellar triangle to occiput; ocellar triangle black, ocellar setae developed, longer than anterior fronto-orbital setae and posterior fronto-orbital setae, extending to anterior margin of frons; anterior fronto-orbital setae reclinate, shorter than posterior fronto-orbital setae. Gena ca. 1/6 height of eye. Antenna brownish yellow, first flagellomere blackish brown on 2/3 apex of dorsal margin, 1.7 times longer than high; arista blackish brown except paler basally, pubescent with longest setulae almost as long as 1/4 height of first flagellomere. Proboscis blackish brown, with pale yellow and black setulae; palpus black with black setulae. Thorax (Fig. 34) black, with gray pruinescence. 0+2 dorsocentral setae, acrostichal setulae in six irregular rows, with pair of strong acrostichal setulae before prescutellar setae; a pair of prescutellar setae, almost as long as anteriormost dorsocentral setae. One anepisternal seta and one katepisternal seta. Legs black, tibia brownish yellow at base (sometimes tibia dark yellow), mid and hind tarsomeres dark yellow (sometimes fore tarsomeres also dark yellow). Fore femur with eight posterior dorsal setae and five posterior ventral setae; fore tibia with one dorsal preapical seta and one short apical ventral seta. Mid femur with three or four anterior setae and one short apical posterior seta; mid tibia with one strong dorsal preapical seta and one strong apical ventral seta. Hind femur with one preapical anterior dorsal seta; hind tibia with one weak dorsal preapical seta and one short apical ventral seta. Wing slight yellow and hyaline, brown at base; costa with 2 nd (between R 1 and R 2+3 ), 3 rd (between R 2+3 and R 4+5 ), and 4 th (between R 4+5 and M 1 ) sections in proportion of 9.6 : 2.5 : 1.7; r-m beyond middle of discal cell; ultimate and penultimate sections of M 1 in proportion of 6.5 : 3.7; ultimate section of CuA 1 ca. 1/5 of penultimate. Haltere pale yellow. Abdomen (Fig. 35) black, with sparse gray pruinescence. Male genitalia : syntergosternite circular, broad dorsally and narrow ventrally. Dorsal of epandrium narrower than dorsal of syntergosternite. Surstylus separated from epandrium, claviform, with a long seta in the middle, expanded apically in lateral view and coneshaped in posterior view, with connective weakly sclerotized claviform sclerite; hypandrium wide on both sides and concave in the middle, U-shaped. Postgonite hairy. Aedeagus with pair of ventral sclerites on basal 1/3 in ventral view, with membranous spiny processes apically, with small apical concave; aedeagal apodeme tubular, as long as half length of aedeagus.
Remarks. The new species is very similar to Minettia (Minettiella) tianmushanensis Shi & Yang from Hainan in the following characteristics: mesonotum with 0 + 2 dorsocentral setae, a pair of strong acrostichal setulae present in front of prescutellar setae; the mid femur with three or four anterior setae; the surstylus is claviform, cone-shaped in posterior view, but it can be separated from the latter in the frons with two black longitudinal stripes along fronto-orbital rows; acrostichal setulae in six irregular rows; aedeagal apodeme as long as half length of aedeagus. In M. (Minettiella) tianmushanensis, the frons without black longitudinal stripe; acrostichal setulae in four irregular rows; aedeagal apodeme as long as aedeagus.
The new species is very similar to Minettia (Minettiella) membranacea sp. nov. from Yunnan in the following characteristics: frons with two black longitudinal stripes along fronto-orbital rows, extending from ocellar triangle to occiput; mesonotum with 0 + 2 dorsocentral setae, acrostichal setulae in six irregular rows, and a pair of strong acrostichal setulae present in front of prescutellar setae; wing slight yellow and hyaline, pale yellow at base, but it can be separated from the latter in the fore femur with five posterior ventral setae, the mid femur with four anterior setae, the syntergosternite with one broad membranous process; the hypandrium narrow and U-shaped; the aedeagus with long spines ventrally. In M. (Minettiella) membranacea sp. nov., the fore femur with six posterior ventral setae, the mid femur with three anterior setae, the syntergosternite with one anterior median process in lateral view, one membranous band under ventral bridge; the hypandrium V-shaped; the aedeagus with membranous processes internally.