Teleopsis amnoni, Feijen & Feijen & O., 2019

Feijen, Hans R., Feijen, Cobi & O., P., 2019, An annotated catalogue of the stalk-eyed flies (Diopsidae: Diptera) of India with description of new species in Megalabops Frey and Teleopsis Rondani, Israel Journal of Entomology (Oxford, England) 49 (2), pp. 35-72 : 57-64

Teleopsis amnoni n. sp.

( Figs 30, 31, 33–38, 41–51)

Teleopsis sykesii : Feijen & Feijen 2011: in part, only p. 145, fig. 3.

LSID: urn:lsid:zoobank.org:act:6C132E9F-8438-4418-9F1C-67E17142333B .

Etymology: It is a pleasure to name this species after Dr Amnon Freidberg. He made an important collection of Diopsidae and made the SMNHTAU Diopsidae holdings available for our studies.

Diagnosis: Teleopsis amnoni n. sp. can be recognised by its size, robust habitus, lack of hairiness, wing pattern (no apical spot, uniform infuscation from preapical crossband to apex, broad preapical crossband with much darker anterior half, irregular central band with darker patches along veins, irregular narrow basal crossband, two vague paler spots between basal and central crossbands, three vague paler spots between central and subapical crossbands), wing mostly covered by microtrichia, IVS 4× stalk diameter, OVS 2–3× stalk diameter, base of IVS less than half the stalk diameter, strong facial teeth, mainly glossy collar, blackish brown pollinose scutum and scutellum, ratio scutellar spine/scutellum length ~3.0, incrassate front femora with around 45 (♀) or 50 (♂) tubercles, large glossy spot laterally on terga 1 and 2, pair of pollinose spots on tergum 3, female sternum 5 split on meson but anteriorly still connected, female sternum 6 consisting of two plates, female sternum 7 basally not connected to tergum, female spiracle 7 well into membrane, round spermathecae with around four small pustules, left male spiracle 7 in synsternum, surstyli articulated, long and straight, mesally directed and almost touching on the meson, surstyli only with microtrichia on posterior inner side, bulging and apically broadest male cerci, ratio eye span/body length 0.84 in ♀ and 1.34 in ♂, and assumed sexual dimorphism (D) with regard to eye span of ~1.6–2.0.

T. amnoni n. sp. can be considered as the sister species of T. sykesii ( Table 1) and, as such, forms the second representative of the T. sykesii species-group.

Description: Body length ♀ 6.6 mm, ♂ 6.8 mm; eye span ♀ 5.6 mm, ♂ 9.1 mm; wing length ♀ 4.8 mm, ♂ 5.3 mm; length of scutellar spine ♀ 1.40 mm, ♂ 1.42 mm.

Head. Central part dark brown ( Figs 33, 34), dorsally glossy, laterally and on face pollinose, central knob on face glossy; frons ( Figs 33, 34) with smooth trapezoid section centrally in front of tubercle, slightly elevated anteriorly near groove, surrounded by roughened lateral areas; arcuate groove concolorous; face with ridge parallel to and just below arcuate groove, face with central knob, strong facial teeth, a few pale setulae; eye span small in female (16 % smaller than body length) and very large in male (34 % longer than body length); probably moderate rate of dimorphism in eye span (if D is slightly higher than in D. sykesii , D could well be between 1.6–2.0, see Fig. 51); stalks dark brown, broad apical parts blackish, pollinose; IVS large, 4× diameter of eye stalk ( Fig. 33), base of IVS small, less than half the stalk diameter; OVS 2–3× stalk diameter.

Thorax. Collar glossy blackish brown, except for pollinose ventral and posterior edges; scutum and scutellum blackish brown pollinose ( Figs 30, 31), more densely pollinose on humeral calli; scutellar spines glossy except for pollinose base; pleura blackish brown, dorsal ⅔ pollinose, ventral ⅓ glossy except for pollinose posterior edge; supra-alar spines ( Fig. 30) glossy, 3.5× as long as pleurotergal spines, dorsolaterally directed; scutellar spines almost straight, diverging under an angle of 70° ( Figs 30, 31), ratio scutellar spine/scutellum length in ♀ 3.05 (n=1) and in ♂ 2.95 (n=1), ratio scutellar spine/body length in ♀ and ♂ 0.21; pleurotergal spines pollinose, short and blunt, posterolaterally directed; in pinned specimens apical seta broken off, but in one fly on photographs it could be discerned; some setulae on thorax, scutellar spines with a number of setulae on very indistinct warts.

Wing. Irrorated with three irregular crossbands ( Figs 37, 38); apex (apical ⅐) uniformly infuscated, no apical dark spot ( Figs 30, 31); preapical band broad and well defined, anteriorly half much darker, posterior half just darker than apex, extending basally in cell r4+5, vaguely connected to central crossband in cell r1 and along veins R 4+5 and M 1; three pale spots in between the central and preapical bands, one in cell r2+3, very minor one in cell r4+5 and large one basally in cell m1; irregular central crossband including crossveins r–m and dm–m, reaching from edge to edge, darker around crossvein r–m and veins R 2+3,R 4+5 and M 4; irregular basal band narrow, running from apex of cell c via tip of cell cua to wing edge, vaguely connected to central band in cell r1, cell bm+dm, around vein M 4 and along wing edge, giving two indistinct paler spots in cell br and cell m4, a distinct vein-like dark stripe running from cell cua to more than halfway the wing edge; cell r4+5 narrow basally, broad centrally and narrowing towards the apex; vein M 4 from crossvein dm–m onward turning downward and reaching till three-quarters of the distance to the wing edge; glabrous basal areas including basal ⅔ of cell c, posterior basal tip of cell r1, basal half of cell br, basal quarter of cell bm+dm and cell cua except for apex.

Legs. Front leg with brown coxa, trochanter and femur, tibia blackish brown, tarsus dark brown with distal segment blackish, coxa 1 pollinose anteriorly, femur 1 largely pollinose on inner side and with pollinose stripe on outer side; mid leg and hind leg brown, apical ⅕ of femora 2 and 3 and tibiae 2 and 3 dark brown; femur 1 ( Figs 30, 31) incrassate in both sexes, ratio of length/width in ♀ 3.6 and in ♂ 3.8, tubercles on distal three-quarters, inner row in ♀ with 26.5 (range 26–27, n=2) and in ♂ with 28.0 tubercles (range 28, n=2), outer row in ♀ with 19.5 tubercles (range 19–20, n=2) and in ♂ with 22 tubercles (range 22, n=2), outer row with small gap.

Preabdomen. Dorsally blackish brown, tergum 3 more chestnut brown, pollinose; on terga 1 and 2 large glossy spot laterally ( Fig. 36); tergum 3 anterolaterally with densely pollinose spots; seam between terga 2 and 3 distinct; sterna dark brown, pollinose, sternum 1 less pollinose; sternum 1 basally just touching syntergum ( Fig. 41); spiracle 1 in tergum; intersclerite laterally connected to sternum 2 ( Fig. 41), sternum 2 very narrow anteriorly and strongly broadening posteriorly; sterna 3 and 4 broad rectangular plates.

Female postabdomen. Deflexed; terga 6 and 7 single rectangular sclerites ( Fig. 42); tergum 8 represented by two rounded sclerites ( Fig. 43), sclerites covered by microtrichia; tergum 10 with laterally small, delineated, more sclerotised sections and with one pair of long setulae ( Fig. 43); cerci rather elongate, ratio of length/width 3.4, covered with microtrichia and a number of setulae; sternum 5 split on meson but anteriorly still connected, sternum 6 mesally narrowly divided in two plates; sternum 7 constricted posteriorly on meson and basally not connected to tergum ( Fig. 42); sternum 8 represented by two rectangular sclerites, posteriorly rounded; spiracle 7 clearly in membrane; subanal plate ( Fig. 44) pentagonal, posteriorly two pairs of long setulae and four pairs of short setulae; spermathecae ( Fig. 46) round, strongly sclerotised, with about four small pustule-like tubercles, duct with no constriction near spermathecae; sclerotised ring of ventral vagina wall ellipsoid, with sharp double bend at one-quarter from posterior end ( Fig. 45).

Male postabdomen. Sterna 5 and 6 short, broad rectangular plates, synsternum 7+8 ( Fig. 49) a short broad sclerite, tapering laterally; left spiracle 7 in synsternum, right spiracle 7 probably in membrane (lost during preparation); epandrium ( Fig. 47) broad, rounded, covered with microtrichia and about 21 pairs of setulae; surstyli articulate, slender, straight, ratio length/width 3.5, mesally directed almost touching on meson ( Figs 35, 47), on inner posterior side with microtrichia, anterior side, apex and outer posterior side glabrous, short setulae present; surstyli connected to lateral side of cerci, not interconnected via processus longi; cerci large, broad, bulging outward in middle, apical ⅓ strongly sclerotised ( Fig. 47), ratio length/ width 1.5, widest near apex, covered with microtrichia and along edges quite long setulae; phallapodeme ( Fig. 48) quite straight, anterior arm hardly curving downward anteriorly, anterior arm ⅓ longer than posterior arm, posterior arm strongly bifurcated, vane broad and strongly sclerotised; aedeagus open structure of long, narrow sclerites, intermittent organ sticking well out from apex; ejaculatory apodeme broadly wedge-shaped ( Fig. 50).

Holotype: ♂ India: Karnataka, Hwy [= Highway] 206, 45 km E Honavar, 14°16.70'N 74°43.21'E, 550 m, 4.xii.2003, I. Yarom ( SMNHTAU).

Paratype: 1♀, same data as holotype .

Additional material: Three sets of photographs are known that clearly show representatives of T. amnoni n. sp. One (Feijen & Feijen 2011, fig. 3) was taken by Mr Shyamal Lakshminarayanan in India, North Wayanad, Kerala (11°49'17"N 75°50'42"E) in x.2006. This photograph is now reproduced ( Fig. 31) with the corrected species name. Photographs by Stephen Marshall ( Fig. 30) were made in India, Fringe Ford, Wayanad, Kerala, 11°52'42.72"N 75°57'57.07"E, 1130 m, on 30.iv.2017. The first photograph by Aniruddha Dhamorikar was taken on vii. 2011 in Tung, Maharashtra, India ( Dhamorikar 2012, slide 96), while the second one (Dhamorikar 2017, fig. 16) from Maharashtra probably shows T. amnoni n. sp. on the left side and a definite T. sykesii on the right.

Distribution: T. amnoni n. sp. is known from Maharashtra, Karnataka and northern Kerala.

Biology: More is known about the habitat of T. sykesii , but T. amnoni n. sp. appears to have similar preferences as both species can be found together. As such, their environment can be described as follows: natural or slightly disturbed forest, not far from a stream and in the Sahyadri (Western Ghats). In the dry season, both Teleopsis can be found in or near cave-like structures. Given their distribution in western India, the two species of the T. sykesii species-group are geographically strongly isolated from other Teleopsis . The two T. sykesii records for Myanmar are very doubtful (Feijen & Feijen 2011). The closest other Teleopsis can be found in Sri Lanka: the equally isolated T. ferruginea species-group (Feijen 2011: 81). Otherwise the nearest Teleopsis members are found in Thailand and Peninsular Malaysia.

The sister species T. sykesii shows moderate sexual dimorphy with regard to the eye span, D=1.51 (Feijen & Feijen 2011). The rate of dimorphy D is calculated as the difference in allometric slope for males and females. Allometric slope is the least-squares regression slope of eye span on body length. For T. sykesii , these slopes are for males 2.65 ± SE 0.10 (n=58) and for females 1.14 ± 0.03 (n=97). Of course, D cannot be determined from two data points available for T. amnoni , but their position in relation to the allometric lines for T. sykesii ( Fig. 51), gives an indication that D for T. amnoni could be slightly higher than for T. sykesii . The difference in ratio eye span/body length is also larger in T. amnoni with 0.84 in ♀ (n=1) and 1.34 (n=1) in ♂. For T. sykesii these ratios are respectively 0.93 (n=97) and 1.23 (n=58).