Simulium (Simulium) doipuiense Takaoka & Choochote, 2005

Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya’Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, Zootaxa 4261 (1), pp. 1-165 : 126-137

Simulium (Simulium) doipuiense Takaoka & Choochote, 2005 (complex)

Simulium (Simulium) doipuiense Takaoka & Choochote, 2005c: 106 –110 (Female, male, pupa and larva). Simulium (Simulium) rufibasis (not Brunetti): Takaoka et al., 2014b: 747.

Specimens examined. One female, three males (all reared from pupae), collected from a stream (width 1.0 m, depth 7 cm, streambed sandy, water temperature 17˚C, exposed to the sun, elevation 999 m, 22˚18’23.788’’N/ 103˚53’42.780’’E), slowly flowing in a grassland, Tavan, Sapa, Lao Cai Province, northern Vietnam, 21-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau; one female, collected while flying around a human, along a road traversing a mountain slope (elevation 997 m, 21˚28’104”N/105˚51’38.687”E), Tam Dao National Park, Vinh Phuc Province, Vietnam, 9-IX-2013, by H. Takaoka, M. Sofian-Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau.

Distribution. Vietnam (Lao Cai and Vinh Phuc).

Remarks. Simulium (S.) doipuiense was described from Thailand ( Takaoka and Choochote 2005c) and was shown to be a species complex consisting of two cytoforms (A and B) by chromosome analysis ( Tangkawanit et al. 2009). According to the original description ( Takaoka and Choochote 2005c), the female of this species is characterized by having a pair of clustered medium-long hairs on the ventral surface of abdominal segment 7, antenna dark brown except the scape, pedicel and first flagellomere yellow, scutum covered with yellow short hairs, hind tibia yellowish white except the apical two-fifths medium to dark brown, and stem of the genital fork without a round apex. The females collected from Vietnam are almost identical to those of S. (S.) doipuiense from Thailand except the following numerical differences (characters of S. (S.) doipuiense from Thailand in parentheses): the relative length of the height of the frons against its narrowest width 1.1 (1.3), relative length of the fore basitarsus against its greatest width 5.1 (4.9), relative width of the hind basitarsus against the hind tibia and femur 0.8 (0.7) and 0.7(0.6), respectively. The males from Vietnam are almost identical to those of S. (S.) doipuiense from Thailand including the number of upper-eye facets in 17 or 18 vertical columns and 18 horizontal rows and the fewer number of spines on the basal protuberance of the style (only several spines), but there is a difference in the relative length of the fore basitarsus against its greatest width (6.7–7.1 in the males from Vietnam versus 5.9–6.1 in those from Thailand). The pupae from both countries are almost identical in many characters including the frons moderately covered with round tubercles.

The female collected from Tam Dao National Park previously reported as S. (S.) rufibasis Brunetti by Takaoka et al. (2014b) was reexamined. Our morphological examination shows that the female differs from that of S. (S.) rufibasis by the antenna dark brown except the scape, pedicel and the base of the first flagellomere yellow, scutum covered with yellow short hairs and hind basitarsus whitish yellow on the basal two-thirds and darkened on the rest. According to the redescription of Puri (1932a), the female of S. (S.) rufibasis has the antennae almost entirely darkened, scutum with brassy short hairs and hind basitarsus whitish yellow on the basal one-third to half and darkened on the rest. The characters of the female are most similar to those of S. (S.) doipuiense , though its hind tibia is yellowish white on the basal half and darkened on the rest, slightly differing from the color of the hind tibia of S. (S.) doipuiense from Thailand which is yellowish white on the basal three-fifths and darkened on the rest. The female collected from Tam Dao National Park is here treated as S. (S.) doipuiense (complex).

Simulium (Simulium) fuscicoxae Takaoka & Ya’cob sp. nov.

Simulium (Simulium) rufibasis (not Brunetti): Takaoka et al., 2015a: 85 .

The female and its associated pupal exuviae and cocoon previously reported from Lam Dong Province, southern Vietnam as S. (S.) rufibasis were reexamined. The result shows that this species is distinguished from S. (S.) rufibasis and other related species. It is here described as a new species.

Female. Body length 2.0 mm. Head. Slightly narrower than thorax. Frons black, shiny, with several dark stout hairs along lateral margins; frontal ratio 1.3:1.0:1.2; frons:head ratio 1.0:3.8. Fronto-ocular area well developed, short, directed laterally, and rounded apically. Clypeus black, grayish pruinose, shiny, moderately covered with dark-brown medium-long hairs though mediolongitudinal portion of upper half widely bare. Labrum 0.68 times length of clypeus. Antenna composed of scape, pedicel and nine flagellomeres, brownish black except scape and pedicel light to medium brown and base of first flagellomere dark yellow. Maxillary palp with five segments, medium brown except third segment dark brown; proportional lengths of third, fourth, and fifth segments 1.0:1.2:2.2; third segment ( Fig. 56 A, B) of moderate size, with medium-sized ellipsoidal sensory vesicle (0.3 times length of third segment) having large opening. Maxillary lacinia with 13 or 14 inner and 15 or 16 outer teeth. Mandible with 26 inner and 12 outer teeth. Cibarium ( Fig. 56 C) with 82 minute processes, of which several are vestigial, near posterodorsal margin. Thorax. Scutum black, shiny, white pruinose when illuminated at certain angles, moderately covered with dark short fine hairs interspersed with several dark-brown long upright hairs on prescutellar area. Scutellum dark brown, covered with dark-brown upright long and short hairs. Postnotum black, shiny and white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, shiny and white pruinose when illuminated at certain angles, and bare. Legs. Foreleg: coxa light brown; trochanter medium brown with base whitish; femur medium brown with apical cap dark; tibia whitish except apical cap dark brown and base light brown, with median outer surface widely white and with bright white sheen when illuminated at certain angles; tarsus brownish black, with moderate dorsal hair crest; basitarsus greatly dilated, 5.1 times as long as its greatest width. Midleg: coxa brownish black; trochanter medium except basal extreme whitish; femur medium brown except apical cap dark brown; tibia light brown except basal two-fifths whitish and apical cap dark brown, and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus light to medium brown except basal half of basitarsus whitish. Hind leg: coxa dark brown; trochanter light brown; femur medium to dark brown except base light brown; tibia ( Fig. 56 D) medium to dark brown except basal two-fifths white and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus medium brown except little more than basal half of basitarsus (though base light brown) and basal half of second tarsomere white; basitarsus ( Fig. 56 E) nearly parallel-sided, 5.4 times as long as wide, and 0.8 and 0.7 times as wide as greatest widths of hind tibia and femur, respectively; calcipala ( Fig. 56 E) moderately developed, little shorter than wide, and 0.4 times as wide as greatest width of basitarsus; pedisulcus ( Fig. 56 E) well developed; claw simple, without tooth. Wing. Length 1.9 mm. Costa with dark spinules and hairs; subcosta haired except apical half bare; basal section of radius bare; R1 with dark spinules and hairs; R2 with dark hairs; hair tuft on base of radius dark brown; basal cell absent. Halter . White except base darkened. Abdomen. Basal scale medium brown, with fringe of dull hairs. Dorsal surface of abdomen medium brown to brownish black, with light to dark brown short hairs; tergite 2 and 6–9 shiny when illuminated at certain angles. Ventral surface medium brown to brownish black; segment 7 with pair of submedian sternal plates each bearing 18 or 19 stout medium-long to long hairs, of which seven or eight hairs in cluster ( Fig. 56 F). Terminalia . Sternite 8 ( Fig. 56 G) well sclerotized and bare medially, covered with eight to ten long and medium-long stout hairs and few short fine hairs on each side. Ovipositor valve ( Fig. 56 G) nearly tongue-like, rounded posteromedially, membranous except inner margin weakly sclerotized, densely covered with microsetae together with six or seven short fine hairs; inner margin slightly sinuous. Genital fork ( Fig. 56 H) of inverted-Y form; stem slender and well sclerotized, with widened apex three times as wide as middle of stem; arms of moderate width, each with moderately sclerotized projection directed forwardly from lateral ridge. Paraproct in ventral view ( Fig. 56 I) pointed posteromedially, moderately concave anterolaterally, and with strongly sclerotized anteromedial surface bearing few to several sensilla; paraproct in lateral view ( Fig. 56 J) somewhat produced ventrally, 0.5 times as long as wide, covered with 21–24 short to medium-long hairs and numerous microsetae on lateral and ventral surfaces. Cercus in lateral view ( Fig. 56 J) short, rounded posteriorly, 0.5 times as long as its greatest width, and covered with medium-long and short hairs.

Spermatheca ( Fig. 56 K) ovoidal, 1.2 times as long as wide, moderately sclerotized except duct and narrow area of juncture with duct unsclerotized, without discernible reticulate surface patterns; minute internal setae present; accessory ducts subequal in thickness to each other and slightly thicker than main duct.

Pupa. Body length 2.3 mm. Head. Integument including antennal sheaths yellow and moderately covered with round tubercles ( Fig. 57 A); frons with two pairs of unbranched trichomes (anterior trichome medium-long, posterior one long) ( Fig. 57 B); face with pair of unbranched medium-long trichomes ( Fig. 57 C), which are subequal in length to anterior ones of frontal trichomes. Thorax. Integument yellow, moderately covered with round tubercles except dorsal surface of posterior half covered with cone-shaped tubercles; thorax with two long anterodorsal trichomes (posterior trichome broken, not measureable but probably as long as or slightly shorter than anterior one) ( Fig. 57 D), two anterolateral trichomes (anterior trichome medium-long, posterior one long) ( Fig. 57 E), one medium-long mediolateral trichome ( Fig. 57 F), and three ventrolateral trichomes (one short and two medium-long) ( Fig. 57 G), on each side; all trichomes unbranched. Gill ( Fig. 57 H) with six slender thread-like filaments in three pairs (one dorsal, one middle and one ventral) arising from short common basal stalk; basal fenestra small; all pairs short-stalked; stalks of dorsal and ventral pairs lying at angle of 90 degrees when viewed laterally; filaments decreasing in length and thickness from dorsal to ventral, with longest filament 1.3 mm long and shortest filament 0.8 mm long; dorsal filament of dorsal pair thickest, and two filaments of ventral pair thinnest; relative thickness of each filament from dorsal to ventral when measured basally 1.0:1.0:0.8:0.8:0.7:0.7; all filaments light brown, tapered toward apex, with moderately developed annular ridges and furrows forming definite reticulate surface patterns except apical half of dorsal pair of filaments and middle and ventral pairs of filaments with weakly or indistinct ridges and furrows, and densely covered with minute tubercles. Abdomen. Dorsally, all segments unpigmented; segment 1 with one unbranched medium-long seta ( Fig. 57 I) on each side; segment 2 with one unbranched short seta and five minute setae ( Fig. 57 J) on each side; segments 3 and 4 each with four distinct hooked spines and one unbranched spinous short seta on each side; segments 5–7 lacking spinecombs; segments 6 with comb-like groups of minute spines on each side; segments 8 and 9 each with distinct spine-combs in transverse row and comb-like groups of minute spines on each side; segment 9 without terminal hooks. Ventrally, segments 4–8 unpigmented and segment 9 somewhat yellowish; segments 3–8 each with comblike groups of minute spines; segment 4 with one unbranched or bifid stout hook and few slender minute setae on each side; segment 5 with pair of bifid stout hooks submedially and few unbranched short setae on each side; segments 6 and 7 each with pair of bifid inner and unbranched outer stout hooks somewhat separated from each other, and few unbranched short setae on each side. Grapnel-shaped hooklets absent on each side of segment 9. Cocoon ( Fig. 57 K). Wall-pocket-shaped, roughly woven anteriorly with many small open spaces in webs, ochreous, and not extended ventrolaterally; individual threads visible; 2.0 mm long by 1.0 mm wide.

Male and mature larva. Unknown.

Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [ UMSRP: Vietnam 0 40, Holotype, Simulium (S.) fuscicoxae , Female, coll. Vietnam, 24-IV-2014, Takaoka et al.], reared from a pupa collected from a small stream (width 1–2 m, water temperature 16.0˚C, exposed to the sun, elevation 1,492 m, 12˚07’59.430”N/108˚35’42.001”E), slowly flowing in open land, 45 km from Dalat , Da Chais , Lac Duong , Lam Dong Province, southern Vietnam , 24-IV-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau.

Biological notes. The pupa of this new species was collected from a slender tree root trailing in the current. Associated species were S. (G.) confertum , S. (S.) chamlongi and S. (S.) nodosum .

Distribution. Vietnam (Lam Dong).

Etymology. The species name fuscicoxae refers to the dark fore coxae of the female of this new species.

Remarks. Simulium (S.) fuscicoxae sp. nov. is assigned to the S. tuberosum species-group of the subgenus Simulium , defined by Rubtsov (1956), based on the unpatterned female scutum, simple claw, paired clustered hairs on the seventh sternite ( Fig. 56 F), and ordinary ovipositor valves ( Fig. 56 G), pupal gill with six slender filaments ( Fig. 57 H) and simple wall-pocket-shaped cocoon ( Fig. 57 K).

This new species is characterized in the female by a sensory vesicle having a large opening ( Fig. 56 A), dark short hairs on the scutum, darkened fore coxae, a pair of clustered stout hairs on the ventral surface of abdominal segment 7 ( Fig. 56 F), and in the pupa by lacking spine-combs on the dorsal surface of abdominal segment 7. By having the darkened female fore coxae and pupal abdominal segment 7 lacking spine-combs, this new species is distinguished from seven of eight related species with a pair of clustered stout hairs on female sternite 7: S. (S.) rufibasis Puri and S. (S.) ramosum Puri from India, S. (S.) doipuiense (complex), S. (S.) manooni Takaoka & Choochote , S. (S.) weji Takaoka , all from Thailand, S. (S.) neorufibais Sun , and S. (S.) xinbinen Sun , both from China ( Chen and An 2003; Puri 1932a; Takaoka 2001a; Takaoka and Choochote 2005c). The remaining species, S. (S.) setsukoae Takaoka & Choochote , from Thailand, which has the darkened female fore coxae, differs from this new species by having a longer female sensory vesicle (0.4–0.5 times the length of the third maxillary palpal segment) with a moderate-sized opening, and triangular ovipositor valves, each with a pointed posteromedian tip ( Takaoka and Choochote 2004a).

Simulium (Simulium) rosliramlii Takaoka & Chen sp. nov.

Female. Body length 2.5–2.9 mm. Head. Slightly narrower than thorax. Frons black, shiny, with several dark stout hairs along lateral margins; frontal ratio 1.3:1.0:0.9–1.1; frons:head ratio 1.0:3.4–3.8. Fronto-ocular area well developed, short, directed laterally, and rounded apically. Clypeus black, grayish pruinose, shiny, moderately covered with dark-brown medium-long hairs though mediolongitudinal portion of upper half widely bare. Labrum 0.7–0.8 times length of clypeus. Antenna composed of scape, pedicel and nine flagellomeres, dark brown to brownish black (though base of first flagellomere light brown). Maxillary palp with five segments, medium brown except third segment dark brown; proportional lengths of third, fourth, and fifth segments 1.0:1.0–1.1:2.3–2.4; third segment ( Fig. 58 A) of moderate size, with medium-sized ellipsoidal sensory vesicle (0.3–0.4 times length of third segment) having medium-sized or large opening. Maxillary lacinia with11–14 inner and 11–17 outer teeth. Mandible with 33–35 inner and 12 or 13 outer teeth. Cibarium ( Fig. 58 B) with 98–110 minute processes, of which several are vestigial, near posterodorsal margin. Thorax. Scutum black, shiny, white pruinose when illuminated at certain angles, moderately covered with yellow short fine hairs interspersed with several dark-brown long upright hairs on prescutellar area. Scutellum dark brown, covered with dark-brown upright long and short hairs. Postnotum black, shiny and white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, shiny and white pruinose when illuminated at certain angles, and bare. Legs. Foreleg: coxa yellow; trochanter medium brown with base yellow; femur medium brown with apical cap dark brown; tibia whitish except apical cap dark brown and base light brown, with median outer surface widely white and with bright white sheen when illuminated at certain angles; tarsus black, with moderate dorsal hair crest; basitarsus moderately dilated, 6.4–7.2 times as long as its greatest width. Midleg: coxa brownish black; trochanter medium to dark brown; femur dark brown except apical cap brownish black; tibia dark brown except basal twofifths whitish and apical cap brownish black, and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus light to medium brown except basal half of basitarsus whitish yellow. Hind leg: coxa dark brown; trochanter dark yellow to light brown; femur dark brown except base dark yellow to light brown; tibia ( Fig. 58 C) medium to dark brown except basal half or little more or less yellowish white, and apical cap brownish black, and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus medium brown except little less than basal two-thirds of basitarsus (though base light brown) and basal half of second tarsomere yellowish white; basitarsus ( Fig. 58 D) nearly parallel-sided, 6.3–6.9 times as long as wide, and 0.7–0.8 and 0.7 times as wide as greatest widths of hind tibia and femur, respectively; calcipala ( Fig. 58 D) moderately developed, slightly shorter than wide, and 0.4 times as wide as greatest width of basitarsus; pedisulcus ( Fig. 58 D) well developed; claw simple, without tooth. Wing. Length 2.5–2.7 mm. Costa with dark spinules and hairs; subcosta haired except apical one-fourth to two-fifths bare; basal section of radius bare; R1 with dark spinules and hairs; R2 with dark hairs; hair tuft on base of radius dark brown; basal cell absent. Halter . White except base darkened. Abdomen. Basal scale dark brown, with fringe of dull hairs. Dorsal surface of abdomen dark brown to brownish black, with light to dark brown short hairs; tergite 2 and 6–9 shiny and iridescent when illuminated at certain angles. Ventral surface medium brown to brownish black; segment 7 with pair of submedian sternal plates each bearing 15–20 stout long hairs ( Fig. 58 E). Terminalia . Sternite 8 ( Fig. 58 F) well sclerotized and bare medially, covered with four to seven long and medium-long stout hairs and few short fine hairs on each side. Ovipositor valve ( Fig. 58 F) nearly tongue-like, rounded posteromedially, membranous except inner margin weakly sclerotized, densely covered with microsetae together with seven or eight short fine hairs; inner margin slightly sinuous. Genital fork ( Fig. 58 G) of inverted-Y form; stem slender and well sclerotized, with widened apex three to four times as wide as middle of stem; arms of moderate width, each with moderately sclerotized projection directed forwardly from lateral ridge. Paraproct in ventral view ( Fig. 58 H) pointed posteromedially, moderately concave anterolaterally, and with strongly sclerotized anteromedial surface bearing six to eight sensilla; paraproct in lateral view ( Fig. 58 I) somewhat produced ventrally, 0.7 times as long as wide, covered with 26–30 short to medium-long hairs and numerous microsetae on lateral and ventral surfaces. Cercus in lateral view ( Fig. 58 I) short, rounded posteriorly, 0.6 times as long as its greatest width, and covered with medium-long and short hairs. Spermatheca ( Fig. 58 J) ovoidal, 1.2 times as long as wide, moderately sclerotized except duct and narrow area of juncture with duct unsclerotized, without discernible reticulate surface patterns; minute internal setae present; accessory ducts subequal in thickness to each other and slightly thicker than main duct.

Male. Body length 2.9–3.4 mm. Head. Slightly wider than thorax. Upper eye medium brown, with large facets in 20–22 vertical columns and in 21 or 22 horizontal rows. Clypeus black, thickly white pruinose, shiny when illuminated at certain angles, covered with dark-brown hairs along lateral margins and near ventral margin (medial portion of upper half bare). Antenna composed of scape, pedicel and nine flagellomeres, brownish black; first flagellomere elongate, 1.6–1.9 times as long as second one. Maxillary palp grayish to dark brown, composed of five segments with proportional lengths of third, fourth, and fifth segments 1.0:1.1:2.3–2.6; third segment ( Fig. 59 A) of moderate size; sensory vesicle ( Fig. 59 A) small, ellipsoidal (0.2–0.3 times as long as third segment), and with small opening. Thorax. Scutum black, with white pruinose pattern, i.e., anterior pair of crescent spots (though not sharply pointed posteriorly) on shoulders extended posteriorly along lateral margins and narrowly connected near base of wings to large transverse posterior spot entirely covering prescutellar area; these pruinose areas silvery when illuminated at certain angles; scutum uniformly and moderately covered with brassy recumbent short hairs interspersed with dark-brown long upright hairs on prescutellar area. Scutellum brownish black, with several darkbrown long upright hairs. Postnotum black, white pruinose when illuminated at certain angles and bare. Pleural membrane bare. Katepisternum longer than deep, black, white pruinose when illuminated at certain angles, and bare. Legs. Foreleg: coxa medium brown; trochanter medium to dark brown; femur medium to dark brown with apical cap brownish black; tibia dark brown except median large portion widely white on outer surface, and with white sheen widely on outer surface when illuminated at certain angles; tarsus brownish black to black, with moderate dorsal hair crest; basitarsus greatly dilated, 8.3–8.5 times as long as its greatest width. Midleg: coxa brownish black; trochanter dark brown; femur dark brown with apical cap brownish black; tibia dark brown except apical cap brownish black and extreme base light brown; tarsus medium brown except basal one-third of basitarsus light brown. Hind leg: coxa dark brown; trochanter medium brown; femur dark brown except apical cap brownish black and extreme base light brown; tibia dark brown except apical cap brownish black and basal tip dark yellow to light brown; tarsus ( Fig. 59 B) dark brown except basal one-third or little less of basitarsus whitish yellow (though extreme base somewhat darkened) and basal one-third of second tarsomere whitish yellow; basitarsus ( Fig. 59 B) much enlarged, gradually widened from base to apical one-third, then slightly narrowed to apex, 3.5–3.7 times as long as its greatest width, and 1.1 and 1.3–1.4 times as wide as greatest widths of hind tibia and femur, respectively; calcipala ( Fig. 59 B) small, slightly shorter than wide, 0.3 times as wide as greatest width of basitarsus; pedisulcus ( Fig. 59 B) well developed. Halter . White except basal portion darkened. Wing. Length 2.5– 2.6 mm. Other characters as in female except subcosta bare. Abdomen. Basal scale brownish black, with fringe of dark long hairs. Dorsal surface of abdomen brownish black to black, with dark short hairs; segments 2, 6 and 7 each with pair of silvery spots dorsolaterally, those on segment 2 broadly connected in middle to each other. Genitalia. Coxites, styles and ventral plate in ventral view as in Fig. 59 C. Coxite in ventrolateral view subquadrate, 0.7 times as long as wide. Style in medial view ( Fig. 59 D) 2.1 times as long as coxite, somewhat produced dorsally near basal one-third forming low protuberance having several small cone-like spines on its dorsal surface. Style in ventrolateral view ( Fig. 59 E) elongate, 2.7 times as long as its greatest width at base (or at basal one-third), slightly constricted subbasally, tapered from basal one-third to apex. Ventral plate in ventral view ( Fig. 59 C) well sclerotized, with body subquadrate (though slightly narrowed basally, and rounded on each posterolateral corner), posterior margin somewhat concave, and with round projection directed ventrally, which is covered with many minute setae; arms divergent from each other; ventral plate in lateral view ( Fig. 59 F) with posterior margin serrated along basal half or little more; ventral plate in end view ( Fig. 59 G) rounded ventrally, with lateral margin serrated along basal two-thirds, with numerous setae on posterior surface except each side of basal portion bare. Median sclerite in lateral view ( Fig. 59 F) arising just anterior to ventral plate, directed dorsally; median sclerite in caudal view ( Fig. 59 H) plate-like, gradually widened from base to apical one-third, then narrowed to apex, with round apex. Paramere in caudal view ( Fig. 59 I) with several distinct hooks and several smaller ones. Aedeagal membrane ( Fig. 59 I) moderately covered with minute setae, and with moderately sclerotized dorsal plate in form of horizontal bar ( Fig. 59 J). Abdominal segment 10 ( Fig. 59 K, L) without hair or with one or two hairs on ventral surface and three or four hairs on lateral surface on each side. Cercus ( Fig. 59 K, L) small, rounded, with six to nine distinct hairs.

Pupa. Body length 2.6–3.2 mm. Head. Integument including antennal sheaths yellow and bare except face moderately covered with round tubercles ( Fig. 60 A); frons with two pairs of unbranched long trichomes ( Fig. 60 A); face with pair of unbranched long trichomes ( Fig. 60 A), which are slightly shorter than frontal trichomes. Thorax. Integument yellow and widely bare on dorsal surface of anterior half except narrow area along mediolongitudinal line moderately covered with round tubercles; integument moderately covered with round tubercles on ventrolateral surfaces near gills, and sparsely or moderately covered with cone-like tubercles on dorsal surface of posterior half; thorax with two long anterodorsal trichomes (anterior trichome somewhat longer than posterior one) ( Fig. 60 B), two long anterolateral trichomes (anterior trichome slightly thinner and shorter than posterior one) ( Fig. 60 C), one short or medium-long mediolateral trichome ( Fig. 60 D), and three ventrolateral trichomes (one short and two medium-long) ( Fig. 60 E), on each side; all trichomes unbranched except posterior trichome of anterolateral trichomes in one pupa bifid. Gill ( Fig. 60 F) with six slender thread-like filaments in three pairs (one dorsal, one middle and one ventral) arising from short common basal stalk; basal fenestra small; dorsal pair with medium-long stalk, and middle and ventral pairs short-stalked; stalks of dorsal and ventral pairs lying at angle of 67–90 degrees when viewed laterally; filaments decreasing in length and thickness from dorsal to ventral, with longest filament 1.6–2.2 mm long and shortest filament 1.2–1.5 mm long; dorsal filament of dorsal pair thickest, and two filaments of ventral pair thinnest; relative thickness of each filament from dorsal to ventral when measured basally 1.0:0.9:0.8:0.8:0.7:0.7; all filaments medium brown, tapered toward apices, with distinct annular ridges and furrows forming definite reticulate surface patterns (except stalks and short basal portions of four filaments of middle and ventral pair smooth), and densely covered with minute tubercles. Abdomen. Dorsally, all segments unpigmented except segment 1 light yellowish; segment 1 with one unbranched medium-long seta ( Fig. 60 G) on each side; segment 2 with one unbranched short seta and five spinous minute setae ( Fig. 60 H) on each side; segments 3 and 4 each with four distinct hooked spines and one unbranched spinous minute seta on each side; segments 5 and 6 lacking spine-combs; segments 6 with comb-like groups of minute spines on each side; segments 7–9 each with distinct spine-combs in transverse row (though those on segment 7 small in number) and comb-like groups of minute spines on each side; segment 9 having pair of small weakly developed terminal hooks ( Fig. 60 I) or not. Ventrally, segments 4–8 unpigmented and segment 9 somewhat yellowish; segments 3–8 each with comblike groups of minute spines; segment 4 with one unbranched or bifid stout hook ( Fig. 60 J) and few slender minute setae on each side; segment 5 with pair of bifid stout hooks submedially and few unbranched short setae on each side; segments 6 and 7 each with pair of bifid inner and unbranched outer stout hooks somewhat separated from each other, and few unbranched short setae on each side. Grapnel-shaped hooklets absent on each side of segment 9. Cocoon. Wall-pocket-shaped, moderately woven, thickly woven, ochreous, and not extended ventrolaterally; individual threads visible; 3.0– 3.5 mm long by 1.5–1.6 mm wide.

Mature larva. Unknown.

Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [ UMSRP: Vietnam 0 41, Holotype, Simulium (S.) rosliramlii , Female, coll. Vietnam, 20-XII-2014, Takaoka et al.], reared from a pupa collected from a river (width 6 m, depth 0.6 m, bottom rocky, water temperature 11.0˚C, exposed to the sun, elevation 1,728 m, 22˚22’22.719”N/103˚45’24.852”E) fast-flowing in forest, Lai Chau, Sapa , Lao Cai Province, northern Vietnam, 20-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau . PARATYPES: Five females and five males, in 80% ethanol, same data as those of the holotype, labeled in each vial as [ UMSRP: Vietnam 0 41, Paratype, Simulium (S.) rosliramlii , coll. Vietnam, 20-XII-2014, Takaoka et al.].

Biological notes. The pupae of this new species were collected from a plastic sheet in the current. Associated species were S. (G.) eshimai sp. nov., S. (N.) laichauense sp. nov. and S. (N.) tayense sp. nov.

Distribution. Vietnam (Lao Cai).

Etymology. The species name rosliramlii is in honor of Dr. Rosli Ramli, Head of Institute of Biological Sciences, University of Malaya, who supported our current research project on black flies in Vietnam.

Remarks. Simulium (S.) rosliramlii sp. nov. is assigned to the S. tuberosum species-group of the subgenus Simulium , based on the male genitalia, of which the ventral plate is quadrate or subquadrate, having a round projection directed ventrally with serrated posterolateral margins when viewed ventrally ( Fig. 59 C, F, G), and the style bears several cone-like spines subbasally on the dorsal surface ( Fig. 59 D).

This new species is characterized in the female by having a pair of clustered stout hairs on the ventral surface of abdominal segment 7 ( Fig. 58 E), and in the pupa by lacking tubercles on the frons ( Fig. 60 A) and anterodorsal surface of the thorax. Among species of the S. tuberosum species-group, only S. (S.) pradyai Takaoka described from Bhutan has a similar combination of these characters ( Takaoka and Somboon 2008). However, this new species is distinguished in the female from S. (S.) pradyai by the following characters (those of S. (S.) pradyai in parentheses): length ratio of the height of the frons against its narrowest width 0.9–1.1 (1.2), antenna entirely darkened (scape, pedicel and base of the first flagellomere yellow), ratio of the length of the fore basitarsus against its greatest width 6.4–7.2 (5.4), and ratio of the length of the hind basitarsus against its greatest width 6.3–6.9 (5.6). The pupa of this new species is distinguished from that of S. (S.) pradyai by the short stalk of the ventral pair of filaments (about half as long as that of the dorsal pair) ( Fig. 60 F) (the stalk of the ventral pair of filaments is about twice as long as that of the dorsal pair in S. (S.) pradyai ).

Simulium (Simulium) giayense Takaoka & Lau sp. nov.

Female. Nearly as in female of S. (S.) rosliramlii sp. nov. except following characters. Body length 2.7 mm. Head. Frontal ratio 1.3–1.4:1.0:1.2. Frons:head ratio 1.0:3.8–4.3. Labrum 0.6–0.7 times length of clypeus. Antenna dark brown to brownish black except base of first flagellomere dark yellow. Maxillary palp: length ratio of third, fourth and fifth segments 1.0:1.1:2.4; sensory vesicle oblong, 0.4 times as long as third segment, with opening of moderate size. Maxilla with 12–14 inner and 15 or 16 outer teeth. Mandible with 33–35 inner and 13–15 outer teeth. Cibarium with 82–107 minute processes. Legs. Fore basitarsus 5.9–6.0 times as long as its greatest width. Hind basitarsus 6.3–6.5 times as long as wide, and 0.7–0.8 and 0.6 times as wide as greatest widths of hind tibia and femur, respectively. Terminalia . Sternite 8 with nine stout long hairs together with four or five short hairs on each side; ovipositor valves each with five or six short hairs; paraproct with 35 or 36 short to long hairs on ventral and lateral surfaces.

Male. Nearly as in male of S. (S.) rosliramlii sp. nov. except following characters. Body length 3.0 mm. Head. Nearly as wide as thorax. Upper eye with large facets in 20 vertical columns and in 20 horizontal rows. Antenna: first flagellomere 1.7 times as long as second one. Maxillary palp: length ratio of third, fourth and fifth segments 1.0:1.2:2.8; sensory vesicle ellipsoidal, 0.2 times as long as third segment. Thorax. Scutum covered with yellow short hairs. Legs. Fore basitarsus 8.0 times as long as its greatest width. Hind basitarsus ( Fig. 61 A) enlraged, gradually widened from base to apical one-third, then narrowed, 3.4 times as long as its greatest width, 1.0 and 1.2 times as wide as greatest widths of hind tibia and femur, respectively; second tarsomere dark brown except basal half yellowish white. Genitalia. Abdominal segment 10 with one or three short hairs on each lateral surface. Cerci round, each nine short to medium-long hairs.

Pupa. Nearly as in pupa of S. (S.) rosliramlii sp. nov. except following characters. Body length 2.8–3.2 mm. Head. Integument ochreous, densely covered with round tubercles ( Fig. 61 B). Thorax. Integument ochreous, densely covered with round tubercles except dorsal surface of posterior portion moderately covered with small tubercles. Mediodorsal trichomes ( Fig. 61 C) long, subequal in length to each other, and nearly as long as posterior trichome of anterolateral trichomes ( Fig. 61 D); mediolateral trichome as in Fig. 61 E, and ventrolateral trichomes as in Fig. 61 F. Gill ( Fig. 61 G) with six slender filaments in three pairs, each short-stalked, arising from short common basal stalk; all filaments grayish brown, decreasing in length and thickness from dorsal to ventral; dorsal filament of dorsal pair longest (2.4 mm long), and ventral filament of ventral pair shortest (1.3 mm long); relative thickness of filaments from dorsal to ventral 1.0:0.9:0.8:0.8:0.7:0.7; stalk of dorsal pair of filaments lying at 60 degree against stalk of ventral pair when viewed laterally. Abdomen. Terminal hooks absent.

Mature larva. Unknown.

Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [ UMSRP: Vietnam 0 42, Holotype, Simulium (S.) giayense , Female, coll. Vietnam, 20-XII-2014, Takaoka et al.], reared from a pupa collected from a small stream (width 0.5 m, bottom rocky, water temperature 11.0˚C, exposed to the sun, elevation 1,750 m, 22˚21’43.110”N/103˚47’19.221” E) moderately flowing in a secondary forest, Sapa , Lao Cai Province, northern Vietnam , 20-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau. PARATYPES: One female and one male (both reared from pupae), in 80% ethanol, same data as those of the holotype labeled in a vial as [ UMSRP: Vietnam 0 42, Paratype, Simulium (S.) giayense , coll. Vietnam, 20-XII-2014, Takaoka et al.].

Biological notes. The pupae of this new species were collected from plastic sheets in the current. Associated species were S. (M.) nigrofilum sp. nov., S. (N.) tayense sp. nov., S. (S.) laocaiense sp. nov., S. (S.) sapaense sp. nov. and S. (S.) turgidum sp. nov.

Distribution. Vietnam (Lao Cai).

Etymology. The species name giayense refers to the land in which the Giay tribe lives.

Remarks. This new species is similar in the female to S. (S.) rosliramlii sp. nov. but is distinguished in the male by the scutum covered with yellow short hairs, and in the pupa by the frons and dorsal surface of the anterior half of the thorax densely covered with tubercles ( Fig. 61 B). This new species is distinguished from S. (S.) rufibasis from India ( Puri 1932a) by the female and male scuta covered with yellow short hairs (brassy or coppercolored short hairs in S. (S.) rufibasis ), female hind basitarsus yellowish white on the basal three-fifths (yellowish white on the basal half or basal one-third in S. (S.) rufibasis ), and male abdomen with segments 2, 6 and 7 each having a pair of shiny dorsolateral patches (segments 2, 5, 6 and 7 each with such shiny patches in S. (S.) rufibasis ). The arrangement of the pupal gill filaments is similar to that of S. (S.) manooni Takaoka & Choochote from Thailand ( Takaoka and Choochote 2005c), from which this new species is distinguished by the pupal frons densely covered with tubercles ( Fig. 61 B) (pupal frons moderately covered with tubercles in S. (S.) manooni ).

Figures

FIGURE 56. Female of Simulium (Simulium) fuscicoxae sp. nov. A & B, Third segments of maxillary palps with sensory vesicles (right side; A, front view; B, lateral view); C, Cibarium (front view); D, Hind tibia (left side; outer view); E, Hind basitarsus and second tarsomere (left side; outer view). F, Cluster of hairs on sternite 7 (left half); G, Sternite 8 and ovipositor valve (right side only; ventral view); H, Genital fork (ventral view); I & J, Paraprocts and cerci (I, ventral view; J, lateral view). K, Spermatheca. Scale bars. 0.1 mm for D and E; 0.02 mm for A – C and F – K.

FIGURE 57. Pupa of Simulium (Simulium) fuscicoxae sp. nov. A, Frons moderately covered with tubercles (left half; front view); B, Frontal trichomes; C, Facial trichome; D – G, Thoracic trichomes (D, anterodorsal; E, anterolateral; F, mediolateral; G ventrolateral); H, Anterior part of thorax and gill filaments (right side; outer view); I, Hair-like seta on dorsal surface of abdominal segment 1; J, Hair-like seta and minute seta on dorsal surface of abdominal segment 2; K, Cocoon (lateral view). Scale bars. 0.5 mm for K; 0.1 mm for H; 0.02 mm for A – G, I and J.

FIGURE 58. Female of Simulium (Simulium) rosliramlii sp. nov. A, Third segment of maxillary palp with sensory vesicle (right side; front view); B, Cibarium (front view); C, Hind tibia (left side; outer view); D, Hind basitarsus and second tarsomere (left side; outer view). E, cluster of hairs on sternite 7 (right half); F, Sternite 8 and ovipositor valve (right side only; ventral view); G, Genital fork (ventral view); H & I, Paraprocts and cerci (H, ventral view; I, lateral view). J, Spermatheca. Scale bars. 0.1 mm for C and D; 0.02 mm for A, B and E – J.

FIGURE 59. Male of Simulium (Simulium) rosliramlii sp. nov. A, Third segment of maxillary palp with sensory vesicle (right side; front view); B, Hind basitarsus and second tarsomere (left side; outer view); C, Coxites, styles and ventral plate (ventral view); D & E, Styles (right side; D, medial view; E, ventrolateral view); F, Ventral plate and median sclerite (lateral view); G, Ventral plate (caudal view); H, Median sclerite (caudal view); I, Paramere and aedeagal membrane (left side; caudal view); J, Dorsal plate (caudal view); K & L, Abdominal segment 10 and cerci (right side; K, lateral view; L, caudal view). Scale bars. 0. 1 mm for B; 0.02 mm for A and C – L.

FIGURE 60. Pupa of Simulium (Simulium) rosliramlii sp. nov. A, Frons bare except near face moderately covered with tubercles (left half; front view); B – E, Thoracic trichomes (B, anterodorsal; C, anterolateral; D, mediolateral; E ventrolateral); F, Anterior part of thorax and gill filaments (right side; outer view); G, Hair-like seta on dorsal surface of abdominal segment 1; H, Hair-like seta and minute seta on dorsal surface of abdominal segment 2; I, Terminal hooks (caudal view); J, Bifid hooklet on ventral surface of abdominal segment 4. Scale bars. 0.1 mm for F; 0.05 mm for A; 0.02 mm for B – E and G – J.

FIGURE 61. Male and pupa of Simulium (Simulium) giayense sp. nov. A, Male; B – G, Pupa. A, Hind basitarsus and second tarsomere (left side; outer view); B, Frons densely covered with tubercles (left half; front view); C – E, Thoracic trichomes (C, mediodorsal; D, anterolateral; E, mediolateral; F ventrolateral); G, Anterior part of thorax and gill filaments (right side; outer view). Scale bars. 0.1 mm for A and G; 0.05 mm for B; 0.02 mm for C – F.