Hirtodrosophila minshanensis Chen, Katoh & Gao, 2019

Chen, Yu, Katoh, Takehiro K. & Gao, Jian-Jun, 2019, The Hirtodrosophila melanderi species group (Diptera: Drosophilidae) from the Huanglong National Nature Reserve, Sichuan, China, Zootaxa 4623 (1), pp. 113-131 : 118-120

Hirtodrosophila minshanensis Chen, Katoh & Gao , sp. nov.

( Figs 2 A–D, 4A–F, 6)

Diagnosis. Surstylus with 14–21 long, trichoid setae on inner mesal surface ( Fig. 6F ). Lateral processes of aedeagus (fork of aedeagus) with branches pointed apically, and finely serrate on apex to lateral margin ( Fig. 6 I–K, M). NT status = G (190), T (526), and C (574) ( Table 2 ).

Description (♂, ♀). Head ( Figs 2A, B , 4 A–F): Eye red with dense interfacetal setulae. Frontal vitta brown. Fronto-orbital plate dark brown, anteriorly and posteriorly paler, with several setulae slightly shorter than anterior reclinate orbital; anterior reclinate orbital situated between proclinate and posterior reclinate orbitals. Ocellar triangle dark brown, with a few small setae inside and behind triangle made by ocelli; ocellar setae inserted slightly outside triangle made by ocelli. Face and facial carina brown to dark brown, carina broad, high ventrally. Gena yellowish brown, darker anteriorly. Subvibrissa stout, differentiated from other orals. Occiput and postgena dark brown. Pedicel grayish brown; first flagellomere grayish brown; arista with 3–5 dorsal and one ventral branches in addition to terminal fork. Supracervical setae nine per side, thin, apically curved and sharp; postocular setae ca. 29 per side. Clypeus dark brown. Palpus pale yellow, apically grayish, club-shaped, with one apical and one subapical, prominent setae; basal lobe of palpus with a few small setulae. Cibarium not thickened on anterior margin; anterior end of cibarium not dilated; anterolateral corners of cibarium strongly protruded anteriad; dorsal wall of cibarium pear-shaped, with posterior portion oval, with four square arranged anterior sensilla in addition to 5–7 medial and 23–24 posterior sensilla per side. Prementum with 5–7 (one proximal, 2–4 lateral, and two distal) pairs of setae, ventral surface only slightly swollen distally. Labellum with eight pseudotracheae nearly the same in width per side.

Thorax ( Fig. 2A, B ): Postpronotal lobe yellowish brown, with two prominent, subequal setae. Mesonotum yellowish brown to brown with three dark brown, longitudinal stripes: medial one broadened posteriorly, lateral ones beyond dorsocentral setae; dorsocentral setae parallel or slightly convergent. Scutellum dark brown centrally, paler laterally; basal scutellar setae divergent, apical ones cruciate. Notopleuron yellowish brown to brown. Thoracic pleura dark brown, ventrally darker. Acrostichal setulae in six regular rows. Mid katepisternal seta distinctly longer than those below it.

Wing ( Fig. 2A, C ) hyaline, long; veins pale brown to brown; r-m and dm-cu crossveins clear. C 1 setae two, subequal. R 2+3 nearly straight distally, R 4+5 and M 1 nearly parallel distally. Halter whitish yellow, basally grayish.

Legs ( Fig. 2A ) yellowish brown to grayish brown, tarsi distally dark brown. Preapical dorsal setae present on tibiae of all legs; apical setae present on tibiae of midleg; ventral setulae of tarsi rather stout, especially those on apical and proximal portion. Fore- and midleg 1st tarsomeres shorter than total length of four succeeding tarsomeres. Hindleg 1st tarsomere slightly shorter than or as long as total length of the four succeeding tarsomeres.

Abdomen ( Fig. 2A, D ): Tergites glossy, nearly entirely dark grayish brown; male tergite VI+VII show a pale area dorsocaudally. Sternites grayish brown; male sternite V distinctly broader than others.

Male terminalia ( Fig. 6 A–M): Epandrium dark grayish brown, very broad dorsally and narrow ventrally in lateral view, ventral lobe finger-shaped, pubescent except for anterior to ventral margin, with 26–28 long setae, ventral ones longer. Cercus dark grayish brown, positioned low and perpendicular to epandrium, pubescent except for ventral portion, separated from epandrium, with 34–39 long setae, caudoventrally with a patch of short and thick spines in addition to a row of 3–5 black, stout, peg-like spines. Surstylus large, thick, projecting ventrad beyond ventral lobe of epandrium, unpubescent, dorsoproximally fused to epandrium, distally bifid, with two rows of peglike, apically blunt prensisetae, and several short ventral setae; upper row somewhat horizontal and straight, with 10–11 prensisetae, lower row somewhat vertical and curved, with 12–14 prensisetae; ventral inner surface with ca. seven short setae. Tenth sternite broad, oblong, moderately sclerotized, undulant, without distinct ridge. Hypan- drium much broader than long, unpubescent, with a pair of paramedian setae. Gonopods absent. Paramere with 3–4 sensilla as long as or longer than paramedian setae. Aedeagus apically with a pair of lateral processes with inwardcurved branches, pincer-like in ventral view (“fork of aedeagus” hereinafter); aedeagal basal processes and guide absent; aedeagal apodeme straight, thin, much shorter than and fused to aedeagus.

Female terminalia ( Fig. 6 N–P): Tergite VIII dark grayish brown, paler ventrally, pubescent dorsally, caudoventrally with ca. four short setae. Epiproct and hypoproct dark grayish brown, nearly entirely pubescent. Sternite VII distally darker, notched caudomedially, nearly entirely pubescent, with several setae. Oviscapt valve distally rounded in lateral view, with ca. six lateral and 13−14 marginal, peg-like ovisensilla, and four (three short, dorsal and one long, ventral) trichoid-like, inner, subterminal sensilla. Spermathecal capsule dark brown, broader than long, with introvert about 9/10 height of capsule; introvert horizontally wrinkled.

Measurements (in mm): BL (straight distance from anterior edge of pedicel to tip of abdomen) = 2.81 in holotype (range in 16♂ paratypes: 1.88–2.98; range in 3♀ paratypes: 2.28–2.65), ThL (distance from anterior notal margin to apex of scutellum) = 1.12 (1.00–1.23; 1.18–1.20), WL (distance from humeral crossvein to wing apex) = 3.21 (2.59–3.30; 3.06–3.35), WW (maximum wing width) = 1.44 (1.22–1.40; 1.30–1.50).

Indices: FW/HW (frontal width/head width) = 0.53 (range in 16♂ and 3♀, or less if noted, paratypes: 0.50– 0.55), ch/o (maximum width of gena/maximum diameter of eye) = 0.28 (0.22–0.38), prorb (proclinate orbital seta/ posterior reclinate orbital seta in length) = 0.66 (11♂, 3♀: 0.55–0.77), rcorb (anterior reclinate orbital seta/posterior reclinate orbital seta in length) = 0.39 (11♂, 3♀: 0.30–0.39), vb (subvibrissa/vibrissa in length) = 0.39 (15♂, 3♀: 0.28–0.58), orbito (distance between proclinate and posterior reclinate orbital setae/distance between inner vertical and posterior reclinate orbital setae) = 0.75 (0.54–0.89), dcl (anterior dorsocentral seta/posterior dorsocentral seta in length) = 0.54 (0.52–0.71), sctl (basal scutellar seta/apical scutellar seta in length) = 1.11 (16♂, 1♀: 1.01–1.21), sterno (anterior katepisternal seta/posterior katepisternal seta in length) = 0.44 (0.60–0.86), dcp (distance between ipsilateral dorsocentral setae/distance between anterior dorsocentral setae) = 0.48 (0.40–0.55), sctlp (distance between ipsilateral scutellar setae/distance between apical scutellar setae) = 1.11 (1.10–1.53), C (2nd costal section between subcostal break and R 2+3 /3rd costal section between R 2+3 and R 4+5) = 3.09 (2.73–3.61), 4c (3rd costal section between R 2+3 and R 4+5 /M 1 between r-m and dm-cu) = 0.71 (0.48–0.76), 4v (M 1 between dm-cu and wing margin/M 1 between r-m and dm-cu) = 1.43 (1.02–1.48), 5x (CuA 1 between dm-cu and wing margin/dm-cu between M 1 and CuA 1) = 1.45 (1.14–1.50), ac (3rd costal section between R 2+3 and R 4+5 /distance between distal ends of R 4+5 and M 1) = 2.53 (2.00–2.75), M (CuA 1 between dm-cu and wing margin/M 1 between r-m and dm-cu) = 0.45 (0.29–0.43), C3F (length of heavy setation in 3rd costal section/length of 3rd costal section) = 0.43 (0.30–0.45).

Holotype. ♂ (#06466), CHINA: Danyunxia Station, Huanglong Nature Reserve, Songpan , Sichuan, 32°43'36" N, 104°02'55" E, 2,140 m, 16.ix.2018, ex banana trap, J.J. Gao, W.F. Zhang, and Y.F. Zou.

Paratypes. CHINA: 1♂ (#06467), same data as holotype ; 15♂ (#06444−48, #06451, #06452, #06454, #06456−62), 3♀ (#06449, #06463, #06464), Huanglong scenic area, Huanglong Nature Reserve, Ngawa , Sichuan, China , 32°45'07" N, 103°49'18" E, 3,200 m, 13−14.xi.2018, by net sweeping, J.J. Gao .

Distribution. China (Sichuan).

Etymology. Pertaining to the type locality, the Minshan Mountains area.

Remarks. This species closely resembles H. seticlasper Katoh & Gao, 2018 and H. spinicerca Katoh & Gao, 2018 in the shape of terminalia, but can be distinguished from it by fewer setae on inner surface of surstylus (41−56 in H. seticlasper and 29−31 in H. spinicerca ; Katoh et al., 2018), and the molecular diagnostic sites also can distinguish this species from the others ( Table 2 ).

Figures

FIGURE 2. Left lateral habitus, head and thorax (dorsal view), wing (left ventral or right dorsal view), and abdomen (dorsal view). A−D, H. minshanensis sp. nov. (holotype #06466); E−H, H. lambda sp. nov. (holotype #06453). Scale bar (dashed) = 0.5 mm (the same in the following figures).

FIGURE 4. Head (anterior view), postocciput (posterior view), cibarium (dorsal and lateral view), and prementum (ventral and lateral view). A−F, H. minshanensis sp. nov. (paratype #06449); G−L, H. lambda sp. nov. (paratype #06455). Abbreviations: cly = clypeus, m s = medial sensilla, p s = posterior sensilla, spc s = supracervical setae. Scale bar (solid) = 0.1 mm (the same in the following figures).

FIGURE 6. Hirtodrosophila minshanensis sp. nov. (A−M: paratype #06444; N−P: paratype #06449). A, B, periphallic organs (posterior and posterolateral view, respectively); C, ventral lobe of epandrium (lateral view); D, cerci (ventral view); E, dorsal part of surstylus (posterolateral view); F, inner surface of surstylus (posterolateral view); G, H, 10th sternite (anterior and ventral view, respectively); I−K, phallic organs (ventral, ventrolateral, and lateral view, respectively); L, sensilla of paramere (ventrolateral view; pointed with red arrow); M, fork of aedeagus (ventral view); N, O, oviscapt (ventral and lateral view, respectively); P, spermatheca.Abbreviations: aed = aedeagus, aed a = aedeagal apodeme, cerc = cercus, epand = epandrium, hypd = hypandrium, pm = paramere, sur = surstylus.