Rhaphium mediocre ( Becker, 1922 )

Grootaert, Patrick, Taylor, Christopher & Guénard, Benoit, 2019, Three new species of Rhaphium Meigen, 1803 from mangroves in Hong Kong (Diptera: Dolichopodidae: Rhaphiinae), European Journal of Taxonomy 540, pp. 1-21 : 17-19

Rhaphium mediocre ( Becker, 1922)

Figs 7 , 9

Porphyrops mediocris Becker, 1922: 59 (type localities: Taihoku and Kankau, Taiwan).

Rhaphium mediocre – Negrobov 1979: 511 , figs 1816–1818 (fig. 1816: lectotype male terminalia, lateral view; fig. 1817: epandrium, ventral view; fig. 1818: cercus, dorsal view). — Yang et al. 2011: 1277, fig. 806. — Tang et al. 2016 (key).

Diagnosis

Medium-sized species (3.2 mm). Male: legs yellow except fore coxa black, fore femur dark brown, tip of hind femur, base and tip of hind tibia and all hind tarsomeres black. Postpedicel elongate triangular, twice as long as wide, arista 1.2 × as long as postpedicel. Postocular bristles black, mixed with some white bristles. Fore coxa with long black bristles only. Tip of mid coxa with a number of adhered bristles forming a thorn. Hind coxa with a long and a short black exterior bristle near tip.

Type material

Lectotype

TAIWAN • ♂; Taipei; H. Sauter leg.; 1912; see Fig. 9 inset for the labels; Museum für Naturkunde, Berlin; MfN.

Remarks

The type locality of the lectotype is Taihoku in Taiwan, an alternative name for modern Taipei. Becker (1922) mentions one male and three females from Taihoku and Kankau, April 1912 (leg. Sauter) in the Hungarian National Museum. It is likely that these have been destroyed. Furthermore, he mentions two males and two females from Taihoku, November 1912 (leg. Sauter), which are now held by the Museum für Naturkunde in Berlin. A lectotype male was designated by Negrobov (1979) and the male terminalia were drawn and published.

More differences are provided under the comments on R. canniccii sp. nov.

Key to the Chinese Rhaphium micans group, modified after Qilemoge et al. (2019)

Species with postpedicel at most 2.5 × as long as wide; fore tarsus simple; fore femur without strong ventral bristles or long hairs, at most half as long as width of femur. Note that R. lumbricus also belonging to the micans -group has the fore tarsomere 1 dorsally depressed, but is strongly raised ventrally (Qilemoge et al., loc. cit.).

21. Fore tarsomere 1 with row of strong ventral bristles on basal half, tarsomere 2 inflated apically ( Yang et al. 2011: fig. 807c) ....................................................................................................................... 22 – Fore tarsomere 1 without distinct ventral bristles, tarsomere 2 simple ........................................... 23

22. Fore and mid femora yellow apically, fore and mid tibia yellow; fore coxa with black bristles and hairs ............................... ............................................................................ R. micans (Meigen, 1824) – Fore femur, mid and hind tarsi dark; fore coxa with light yellow bristles and hairs .......................... .................................................................................................................... R. dispar Coquillett, 1898

23. All coxae dark, fore and mid femora yellow apically .................................................................... 24 – Basal half of fore coxa and apical ⅓ of hind femur dark ............................................................... 25

24. Hind tibia with 3 ventral bristles; mid tarsomere 1 1.1 × as long as hind tarsomere 1 ....................... .................................................................................. R. wuduanum Wang, Yang & Masunaga, 2005

– Hind tibia without distinct ventral bristles; mid tarsomere 1 1.4 × as long as hind tarsomere 1 ........ .................................................................................................................. R. gansuanum Yang, 1998

25. Mid coxa with 1 strong outer bristle and bunch of ventral bristles; mid tibia with 1 anteroventral ... ......................................................................................................................................................... 26 – Mid coxa only with only 1 strong outer bristle at middle, without bunch of ventral bristles; mid tibia without ventral bristles .......................................................... R. bisectum Tang, Wang & Yang, 2016

26. Squama with yellow hairs; cercus not bifoliate; surstylus short and thick ( Fig. 6 ) ....................... 27 – Squama with black hairs; cercus bifoliate; surstylus basally thick, apically sharp, with one protuberance ............................................................ R. tianshuiense Qilemoge, Wang & Yang, 2019

27. Postpedicel less than twice as long as wide (between 1.6–1.7 ×), arista at most 2 × as long as postpedicel; fore femur entirely yellow ( Fig. 5 ) ....................................................... R. canniccii sp. nov.

– Not with this combination of characters. Postpedicel 2 × as long as wide. Fore femur brownish above dorsally ................................................................................................................................ 28

28. Postpedicel twice as long as wide, arista at most 1.2 × as long as postpedicel ( Fig. 7 ) ..................... ................................................................................................................. R. mediocre ( Becker, 1922)

– Postpedicel twice as long as wide, arista 3 × as long as postpedicel ( Fig. 8 ) ..................................... ................................................................................................................... R. eburnea ( Parent, 1926)

Figures

Fig. 7. Rhaphium mediocre (Becker, 1922), lectotype, ♂, head in lateral view (coll. mfn-berlin). (Photo credit Mr Bernhard Schurian and Sven Marotske)

Fig. 9. Rhaphium mediocre (Becker, 1922), lectotype, ♂, habitus, with labels and preparation of male terminalia on plastic sheet (MfN). (Photo credit Mr Bernhard Schurian and Sven Marotske)

Fig. 6. Rhaphium canniccii sp. nov., holotype, ♂, terminalia (RBINS). A. Surstylus, lateral view. B. Epandrium, ventral view. C. Epandrium with cerci ventral view. D. Epandrium, lateral view. Abbreviation: hy = hypandrium. Scale bars: 0.1 mm.

Fig. 5. Rhaphium canniccii sp. nov., holotype, ♂, habitus (RBINS). Scale bar: 1 mm. (Photo credit Ms Camille Locatelli)

Fig. 8. Rhaphium eburnea (Parent, 1926), lectotype, ♂, habitus (MNHN). (Photo credit Mr Emmanuel Delfosse, MNHN)