Lichtwardtia polychroma (Loew, 1864)

Tang, Chufei, Yang, Ding & Grootaert, Patrick, 2018, Revision of the genus Lichtwardtia Enderlein in Southeast Asia, a tale of highly diverse male terminalia (Diptera, Dolichopodidae), ZooKeys 798, pp. 63-107 : 63

Lichtwardtia polychroma (Loew, 1864) Figs 16, 17, 18

Rhagoneurus polychromus Loew, 1864: 346, Fig. 3, a, b, c. Male & female. Type locality: Sri Lanka.

Material examined.

There is a single male conserved in the collection of Becker (MfN, Berlin) bearing the label " Rhaconeurus polydromus m" in the handwriting of Loew (Figure 16). We think that the “m” stands for mihi (mine or my species) or for manuscript name. It was this specimen that Becker cited in his 1922 book commenting on the writing error Rhaconeurus by Loew which should have been Rhagoneurus . Becker labelled the specimen zickzak Wied. det. Becker though he published it as zickzack . It bears a third yellow label with "Ceylon Nietner S." in print and in handwriting Rambodda. Below we see in handwriting Loew (Figure 16). Nietner S. means Nietner sammelt.

The information on the locality is new because Loew did not give a precise locality in his description. Rambodda (nowadays cited as Ramboda) is a small village in Sri Lanka known for its famous waterfalls. Johannes (John) Nietner (died 1874) was a German naturalist chiefly interested in botany and entomology. Born in Potsdam, he was a plantation owner in Rambodda, Ceylon and described many new insect species from the island. Having a special interest in insects, he made large collections and sent specimens for study by experts abroad. Collections from him are in the Deutschen Entomologischen Institut, the Museum für Naturkunde in Berlin, in the Naturhistorischen Museum in Vienna and the Natural History Museum in London.

We designate the male as lectotype since Loew did not designate a holotype. A female was included in the description but we failed to find it. Stacked images of the lectotype male were provided by the courtesy of Mr. Bernhard Schurian and Sven Marotske (MfN, Berlin).

Comments.

Zhang et al. 2009 re-described and illustrated a similar species as Lichtwardtia ziczac (Wiedemann). Thanks to her detailed drawings and re-description we could see that her species does not correspond to the female holotype of L. ziczac . The latter has the cross veins brownish seamed (Figure 25). The male that she studied was found on Bali (Indonesia) and we are not sure if it is really conspecific with our L. polychroma from Cambodia although the huge dorsal hook near the tip suggests so. Temporarily we consider the specimens from Cambodia as L. polychroma both having a swelling of the costa, while the species from Bali without swelling of the costa as a different new species.

Additional material examined for the descriptions.

CAMBODIA (all coll. RBINS): 1 male, Siem Reap prov., Angkhor, Preah Khan Temple; 17-24 February 2005, Malaise trap in secondary forest (leg. Oul Yothin). 4 males; same provenance, 24 January– 21 February 2006. 1 male, same provenance, 28 March– 7 April 2006. 1 male; Siem Reap prov., Angkhor, Bakheng; 23-31 October 2005; Malaise trap in secondary forest (leg. Oul Yothin).

Diagnosis.

Antenna largely yellow, legs yellow (Figs 16, 17). Postpedicel 1.5 times as long as wide. Arista-like stylus with rather short hairs. Wing entirely hyaline with a short widening of the costa just before R1 joins the costa. Mid coxa anteriorly with a blackish brown band, posteriorly with a brown band. Hind coxa entirely yellow. Hypandrium (Figure 18) with a strong brown subapical spine. Phallus smooth. Cercus pointed with broadened bristles.

Description.

Male.Body length 4.2 mm, wing 3.8 × 1.3 mm.

Head dark metallic green, with thick pale pollinosity; face slightly raised, frons and face both with thick pale pollinosity, gradually narrowed downward. Hairs and bristles on head black except postocular bristles yellow. Antenna yellow; postpedicel with extreme tip and dorsal margin brownish; elongate triangular, blunt at tip, nearly as long as wide; arista-like stylus with long densely set hairs. Proboscis dark yellow, with short black hairs; palpus, dark yellow with one black apical bristle.

Thorax dark green, with pale grey pollinosity. Hairs and bristles on thorax black; five strong dc, ten pairs of strong acr, with dense short strong bristles at anterior portion. Scutellum with two pairs sc, apical pair long strong, basal pair short and weak. Legs mainly yellow. Fore and hind coxa entirely yellow, but mid coxa with a black band anteriorly and a broad band posteriorly. Fore coxa anteriorly at base with a few short erect bristles, anteriorly densely covered with short black bristle-like hairs, four very long ap and a few shorter bristles. Mid coxa anteriorly densely covered with short black hairs, with a long outer bristle at the tip of the blackish band; hind coxa with two outer bristles, basal one strong, apical one short and weak. Mid and hind trochanters both with several short weak hairs. Fore femur lacking ventral bristles. Mid femur with one preapical pv. Hind femur with one strong ad at apical quarter. Fore tibia with two ad, two pd, one av, and three ap. Mid tibia with two ad, three pd, one av, and four ap; all long strong. Hind tibia with two ad, four pd, one pv, and three ap; all long. Hind tarsomere I with one strong ad at middle, one short strong ad at basal third and two short apical bristle. Relative lengths of tibia and five tarsomeres of legs LI: 9.0: 6.0: 2.4: 1.2: 1.0: 1.0; LII: 16.0: 8.0: 5.0: 4.0: 2.4: 1.6; LIII: 18.0: 6.0: 4.0: 4.0:?:?. Wing nearly hyaline, tinged brownish, veins brown. M with fading M2, M1 with one short subvein. Crossvein dm-cu straight. CuAx ratio 1.1. Lower calypter pale with black hairs. Haltere pale.

Abdomen metallic green, with pale pollinosity. Hairs and bristles on abdomen black.

Male terminalia. Epandrium 1.9 times longer than wide (Figure 18E); epandrial lobe with three long pale ap. Surstylus thin and long with three thin ap and three bristles at middle. Cercus nearly triangular, pale except the thick black seam, with weak digitations around outer margin, with black blade-like marginal bristles on digitations. The tip is elongated with the apical bristle on a papilla. A strong black bristle present on the inner margin of the cercus near the tip. Hypandrium with one large brown hook-like tooth at tip and some tiny denticles on the dorsal margin (Figure 18C). The large brown tooth is resting on the brownish tip of a large pale membranous projections on both sides of the ventral margin of the epandrium (Figure 18B). Phallus bifurcate with a dorsal rounded swelling on the dorsal fork (Figure 18A). Tip of the ventral fork somewhat truncate (Figure 18E).

Female. Unknown.

Comments.

Loew (1864) gave a very detailed description of the male and although he mentioned the small swelling of the costa before the R1 reaches the costa, he did not indicate it on his drawings of the wing ( Loew 1864: figure 3 and 3C). That caused more confusion. Having this characteristic L. polychroma resembles our L. nodulata that has however a larger swelling of the costa on the point where R1 joins the costa (Figs 16, 17) and it lacks the large brown tooth a the tip of the hypandrium. L. zhangae sp. n. from Bali has no broadening before the R1 joins the costa but identical armed hypandrium. Lichtwardtia hirsutiseta has a broad swelling much more in advance of the point where R1 meets the costa; its antenna is also much darker while entirely yellow in L. polychroma . Here again we did not dissect the specimen waiting for appropriate techniques to study the ancient DNA. Nevertheless we think that L. polychroma is conspecific with specimens from Cambodia that we describe above in more detail.

Distribution.

Cambodia, Sri Lanka.