Research Article |
Corresponding author: Ding Yang ( dyangcau@126.com ) Academic editor: Marija Ivković
© 2018 Chufei Tang, Patrick Grootaert, Ding Yang.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Tang C, Grootaert P, Yang D (2018) Protomedetera, a new genus from the Oriental and Australasian realms (Diptera, Dolichopodidae, Medeterinae). ZooKeys 743: 137-151. https://doi.org/10.3897/zookeys.743.22696
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Protomedetera gen. n. (Diptera: Dolichopodidae), a new genus of the subfamily Medeterinae, is described from the Oriental and Australasian realms based on four new species. Protomedetera singaporensis Grootaert & Tang, sp. n. is designated as type of the new genus. The genus is peculiar because of the small body size, the small globular first flagellomere (postpedicel), the simple male genitalia with indistinct or small epandrial lobe and half-hidden cercus. The following four new species are described and illustrated: P. biconvexa sp. n., P. biseta sp. n., P. glabra sp. n., and P. singaporensis sp. n. A key to the species of the new genus is provided.
Australasia, Medeterinae , new genus, Oriental
Medeterinae is a wide spread dolichopodid subfamily which occurs in all geographical realms. Overall, there have been 25 extant genera reported, with three new genera Nikitella, Medeterella, and Demetera defined by
The specimens on which this study is based were partly collected by Dr Olivier Missa in Papua New Guinea, by fogging tree canopies in a primary rain forest in Baiteta (4°59'10.36"S, 145°45'47.05"E; Madang province). This material was first preserved in salt that caused bleaching of the flies. Later they were transferred to 75% ethanol. The Oriental material (Singapore, Malaysia) was collected by hand on tree trunks or rarely in a Malaise trap. The type material is conserved in the collections of the Royal Belgian Institute of Natural Sciences (
Morphological terminology for adult structures mainly follows
The acquisition of the NGS COI barcode of P. singaporensis sp. n. follows the PCR conditions and the primer from
The following abbreviations are used:
acr acrostichal bristle (s),
ad anterodorsal bristle (s),
av anteroventral bristle (s),
dc dorsocentral bristle (s),
npl notopleural bristle (s),
pd posterodorsal bristle (s),
oc ocellar bristle (s),
ph posthumeral bristle,
pp propleuron,
pt postalar bristle (s),
pv posteroventral bristle (s),
sa supraalar bristle (s),
sc scutellar bristle (s),
su sutural bristle (s),
vt verticle bristle(s),
CuAx ratio length of dm-cu / length of distal portion of CuA,
LI fore leg,
LII mid leg,
LIII hind leg.
Protomedetera singaporensis Grootaert & Tang, sp. n.
The name Protomedetera gen. n. is proposed since this genus looks like a small and simplified Medetera.
Body small and stout, body length less than or equal to 2.0 mm. Eye without soft hair between each facet. Two oc, two vt. Scape short and small, almost invisible in lateral view. Pedicel cup-like, large, with first flagellomere sunken in it; usually with long apical bristles over first flagellomere. First flagellomere rounded, wider than long or nearly as long as wide, with short pubescence. Arista nearly bare or shortly pubescent, basal portion of arista very short. Ocellar tubercle distinct but not strongly raised. Upper postcranium deeply concave. Proboscis not strongly sclerotized.
Thorax raised dorsally at shoulder. Mesonotum flat before scutellum. Two h, one ph, one su, two npl, two sa, one pt, five to six dc, biseriate acr. Anterior portion sometimes densely covered by short bristles. Legs only with few bristles, wholly yellow or mainly yellow including tarsomeres. Hind coxa with one weak outer bristle. Hind tibia without any ad/pd/av/pv. Hind tarsomere I short and flat. Wing nearly hyaline, tinged light yellow; veins light brown, R4+5 and M parallel. CuAx ratio no more than 0.25. Squama pale with long pale hairs. Halter pale.
Hypopygium: Epandrium distinctly longer than wide, nearly triangular. Epandrial lobe indistinct or small. Surstylus simple. Cercus half hidden in epandrium, with marginal bristles, covered by short peg-like bristles. Phallus usually hidden in hypandrium, sometimes modified apically.
1 | Pedicel with long apical bristles, longer than total length of pedicel and flagellomere | 2 |
– | Pedicel without long apical bristles | P. glabra sp. n. |
2 | Basal third of costa thickened; cercus (Fig. |
P. biconvexa sp. n. |
– | Basal third of costa not thickened; cercus simple, without apical papillae | 3 |
3 | Width of face at middle 1.4 times as wide as first flagellomere. Pedicel with only one long apical bristle distinctly longer than total length of pedicel and first flagellomere (Fig. |
P. singaporensis sp. n. |
– | Width of face at middle as wide as first flagellomere. Pedicel with two long apical bristles 1.5 times as long as the total length of pedicel and first flagellomere (Fig. |
P. biseta sp. n. |
Pedicel with four apical bristles twice as long as total length of first flagellomere and pedicel. Vein costa bold at basal 1/3. Cercus short thick, with two round apical protuberances each with a strong apical bristle. Hypandrium with one irregular process at apical 2/5 to 1/4, sharp apically. Phallus not modified.
Male (Fig.
Head metallic green, nearly black, with grey pollinosity; eyes separated; face nearly parallel, width of face at middle as wide as first flagellomere. Hairs and bristles on head black, postocular bristles and posteroventral hairs short pale. Two strong oc, two strong vt. Antenna wholly yellow; scape short and small, almost invisible; pedicel cup-like, large, with first flagellomere sunken in it, with circlet of apical bristles of which four very long strong, distinctly covering first flagellomere, twice as long as total length of first flagellomere and pedicel; first flagellomere small, rounded, nearly as long as wide, with tiny pubescence; arista black, almost bare, nearly as long as head width, with basal segment 0.1 times as long as apical segment. Ocellar tubercle distinct but not strongly raised. Upper postcranium deeply concave. Proboscis yellow, not strongly sclerotized, with light thin lines and short strong apical bristle; palpus yellow, slightly raised, rounded, with black preapical bristle.
Thorax raised dorsally at anterior area, dark metallic green, with some grey pollinosity. Mesonotum flat before scutellum. Pp with one strong spine-like bristle at lower 1/3. Hairs and bristles on thorax black; two h, one ph, one su, two npl, two sa, one pt, five dc, six biseriate acr at anterior portion. Anterior portion densely covered by short bristles. Scutellum with one pair of strong sc.
Legs mainly yellow except mid and hind coxae, dorsum of mid and hind femora brown. Hairs and bristles on legs mainly black. One weak prothoracic bristle above fore coxa. Fore coxa at a distance with mid coxa. Mid and hind coxae each with one weak outer bristle at middle. Femora without distinct bristles. Mid tibia with one ad at middle and three apical bristles. Hind tibia with two tiny apical bristles. Hind tarsomere I somewhat shortened and flat. Tibiae and five tarsomeres of legs LI : 2.0 : 1.0 : 0.3 : 0.3 : 0.2 : 0.4; LII : 3.0 : 1.5 : 0.8 : 0.5 : 0.3 : 0.4 ; LIII : 3.5 : 0.8 : 1.0 : 0.8 : 0.4 : 0.5. Wing nearly hyaline, tinged light yellow; veins light brown, costa vein thickened at basal 1/3, R4+5 and M parallel. CuAx ratio 0.25. Squama pale with long pale hairs. Halter pale.
Abdomen metallic green with grey pollinosity. Hairs and bristles black. Hypopygium (Fig.
Female. Unknown.
The name biconvexa means two protuberances, referring to the two apical two protuberances of the cercus.
Holotype male, PAPUA NEW GUINEA, Madang province, Baiteta (4°59'10.36"S, 145°45'47.05"E) FOG XH, 16/III/1994, leg. Olivier Missa (coll.
Paratypes: PAPUA NEW GUINEA, Madang province, Baiteta (4°59'10.36"S, 145°45'47.05"E), FOG AR 15, 15/VI/1995, leg. Olivier Missa; 1 male, FOG AR 24, 5/VII/1995; 1 male, FOG XJ, 7/IV/1994 (coll.
Pedicel with two long apical bristles 1.5 times as long as total length of pedicel and first flagellomere. Cercus nearly oval, 3.6 times as long as wide, narrow at tip, with several long apical marginal bristles and some short peg-like bristles. Hypandrium simple, rounded apically in lateral view. Phallus thin, hook-like apically, with a preapical denticle.
Male (Fig.
Head metallic green, nearly black, with grey pollinosity; eyes separated; face nearly parallel, width of face at middle as wide as first flagellomere. Hairs and bristles on head black, postocular bristles and posteroventral hairs short and pale. Two strong oc, two strong vt. Scape and pedicel yellow; scape short and small, almost invisible; pedicel cup-like, large, with first flagellomere sunken in it, with circlet of apical bristles of which two bristles 1.5 times as long as total length of pedicel and first flagellomere; first flagellomere small, rounded, brown, nearly as long as wide, with tiny pubescence; arista black, almost bare, nearly as long as head, with basal segment extremely short, less than 0.1 times as long as apical segment. Ocellar tubercle distinct but not strongly raised. Upper postcranium deeply concave. Proboscis yellow, not strongly sclerotized, with light thin lines; palpus yellow, slightly raised, rounded, with yellow preapical bristle.
Thorax raised dorsally at front area, dark metallic green, with some grey pollinosity. Mesonotum flat before scutellum. Hairs and bristles on thorax pale; two h, one ph, one su, two npl, two sa, one pt, six dc, five biseriate acr at anterior 1/2. Shoulder portion covered by short bristles. Scutellum with one pair of strong sc.
Legs mainly yellow except mid and hind coxae brown. Hairs and bristles on legs mainly pale. One weak prothoracic bristle above fore coxa. Fore coxa with row of bristles anteriorly. Hind coxa with one weak outer bristle. Fore femur with six pv (three at basal 1/6, three at apical 1/6). Hind femur with four pv at apical 1/4. Mid tibia with one ad at basal 1/3 and three apical bristles. Hind tibia with two apical bristles. Hind tarsomere I somewhat shortened and flat. Tibiae and five tarsomeres of legs LI : 2.5 : 1.1 : 0.5 : 0.3 : 0.2 : 0.4; LII : 3.6 : 1.3 : 0.8 : 0.5 : 0.3 : 0.4 ; LIII :3.5 : 0.8 : 1.0 : 0.8 : 0.4 : 0.5. Wing nearly hyaline, tinged light yellow; veins light brown, R4+5 and M parallel. CuAx ratio 0.2. Squama pale with long pale hairs. Halter pale.
Abdomen metallic green with grey pollinosity. Hairs and bristles black. Hypopygium (Fig.
Female. Unknown.
The name biseta refers to the two long bristles on the pedicel.
Holotype male: PAPUA NEW GUINEA, Madang province, Baiteta (4°59'10.36"S, 145°45'47.05"E), FOG AR 40, 3/VIII/1995, leg. Olivier Missa (in coll.
Paratypes: PAPUA NEW GUINEA, Madang province, Baiteta (4°59'10.36"S 145°45'47.05"E), 2 males, FOG AR 1, 27/IV/1995, leg. Olivier Missa; 1 male, FOG AR 15, 15/VI/1995; 1 male, FOG XA 9, 9/IV/1993, leg. Olivier Missa (in coll.
Pedicel with circlet of short bristles nearly as long as pedicel. Wing veins without any thickness. Cercus rhomboid, with row of long marginal bristles and one long apical bristle, covered by short weak peg-like bristles. Hypandrium simple, black apically.
Male (Fig.
Head metallic green, nearly black, with grey pollinosity; eyes separated; face nearly parallel, width of face at middle 0.6 times as wide as first flagellomere. Hairs and bristles on head black, postocular bristles and posteroventral hairs short pale. Two strong oc, two strong vt. Antenna wholly yellow except first flagellomere brownish at apex, scape and pedicel yellow; scape short and small, almost invisible; pedicel cup-like, large, with first flagellomere sunken in it, with circlet of short bristles nearly as long as pedicel; first flagellomere small, rounded, nearly as long as wide, with tiny pubescence; arista black, almost bare, nearly as long as head, with basal segment extremely short, less than 0.1 times length of apical segment. Ocellar tubercle distinct but not strongly raised. Upper postcranium deeply concave. Proboscis yellow, not strongly sclerotized, with light thin lines; palpus black, small, with black preapical bristle.
Thorax raised dorsally at front area, dark yellow without metallic gross, brownish at propleuron and mesopleuron, with some grey pollinosity. Mesonotum flat before scutellum. Hairs and bristles on thorax pale; two h, one ph, one su, two npl, two sa, one pt, two weak dc, six biseriate acr at anterior 1/2. Shoulder portion densely covered with short bristles. Scutellum with one pair of strong sc.
Legs wholly yellow without distinct bristle. Hind tarsomere I somewhat shortened and flat. Tibiae and five tarsomeres of legs LI : 3.0 : 0.8 : 0.5 : 0.5 : 0.4 : 0.5; LII : 3.5 : 1.3 : 0.8 : 0.6 : 0.4 : 0.5 ; LIII :4.5 : 0.8 : 1.2 : 1.0 : 0.5 : 0.6. Wing nearly hyaline, tinged light yellow; veins light brown, R4+5 and M parallel. CuAx ratio 0.2. Squama pale with long pale hairs. Halter pale.
Abdomen metallic green with grey pollinosity. Hairs and bristles black. Hypopygium: simple, pale. Hairs and bristles pale. Epandrium (Figs
Female (Fig.
The name glabra means bare, referring to the pedicel which has no long bristles and a simple hypandrium.
Holotype male: PAPUA NEW GUINEA, Baiteta (4°59'10.36"S, 145°45'47.05"E), FOG AR 14, 14/VI/1995, leg. Olivier Missa (in coll.
Paratypes: PAPUA NEW GUINEA, same provenance as holotype: 1 male, FOG AR 13, 9/VI/1995; 1 male, FOG AR 9-3, 26/V/1995; SINGAPORE: 2 males, Sime forest, 8/IV/2005, leg. P. Grootaert (in coll. LKCNHM); 1 male, Clementi Woods, 23/IV/2005, drains, leg. I. Van de Velde; 1 female, Nee Soon, 27/IV/2005, leg. P. Grootaert; 1 male, Clementi woods, 25/VI/2005, drains, leg. I. Van de Velde (in coll.
Width of face at middle 1.4 times as wide as first flagellomere. Pedicel with only one long black apical bristle 1.5 times as long as total length of pedicel and first flagellomere. Surstylus with four long apical bristles. Cercus with one long apical bristle.
Male (Fig.
Head metallic green, nearly black, with grey pollinosity; eyes separated; face nearly parallel, width of face at middle 1.4 times as wide as first flagellomere. Hairs and bristles on head black except postocular bristles and posteroventral hairs pale. Two strong oc, two strong vt. Antenna dark yellow except first flagellomere black; scape short and small, almost invisible; pedicel cup-like, large, with first flagellomere sunken in it, with circlet of bristles, all yellow and short except one black and long, 1.5 times as long as total length of pedicel and first flagellomere; first flagellomere small, rounded, nearly as long as wide, pubescent; arista black, pubescent, nearly as long as head, with basal segment extremely short, less than 0.1 times length of apical segment. Ocellar tubercle distinct but not strongly raised. Upper postcranium deeply concave. Proboscis brown with brown apical hairs; palpus brown, small, with strong brown apical bristle.
Thorax raised dorsally at front area, dark metallic green, with some grey pollinosity. Mesonotum flat before scutellum. Hairs and bristles on thorax pale; two h, one ph, one su, two npl, two sa, one pt, five dc, six biseriate acr at anterior 3/5 portion. Shoulder portion densely covered with short bristles. Scutellum with one pair of strong sc.
Legs mainly yellow but coxae, basal 4/5 of femora and tarsomere V brown. Hairs and bristles on legs pale. Bristles on legs thin and hair-like. Fore and mid coxae each with two rows of anterior bristles. Hind femur with one preapical pv. Mid tibia with one ad at basal 1/3 and one short apical bristle. Hind tarsomere I somewhat shortened and flat. Tibiae and five tarsomeres of legs LI : 2.4 : 1.0 : 0.5 : 0.4 : 0.3 : 0.5; LII : 3.5 : 1.2 : 0.8 : 0.5 : 0.3 : 0.4 ; LIII :4.5 : 1.7 : 0.8 : 0.5 : 0.3 : 0.5. Wing nearly hyaline, tinged light yellow; veins light brown, R4+5 and M parallel. CuAx ratio 0.125. Squama pale with long pale hairs. Halter pale.
Abdomen metallic green with grey pollinosity except first segment, with one large black spot laterally at segment V. Hairs and bristles black. Hypopygium (Fig.
Female. Unknown.
The name singaporensis refers to the Republic of Singapore where this species was found.
Holotype male: SINGAPORE, Nee Soon (swamp forest), 2 May 2012 in Malaise trap NS2 (leg. J. Puniamoorthy; in coll. LKCNHM with reference R_ckq_DOL_ZRCBDP00005503_Protomedetera_sp_M_NS2).
The NGS barcode is deposited in GenBank accession number: BankIt2080950 Seq1 MG820472.
The concept “microdolichopodid” by
Overall, the appearance of Protomedetera is similar to Cryptopygiella Robinson, they share the small size of the body and the wing, the long bristle on the pedicel, the biseriate acr, the ratio of crossvein dm-cu and distal CuA. However, the male genitalia of the two genera are quite different. In Cryptopygiella, the male genitalia are almost completely enclosed in the tip of the abdomen; appendages of male genitalia including the cercus, the surstylus, the epandrial lobes, and the hypandrium are all strongly reduced (
Protomedetera is included into Medeterinae for the following features: the flat vertex, the deeply concave upper postcranium, the suboval first flagellomere and the apical arista, the parallel sided face, the pollen on the face obscuring the metallic ground-colour, the strongly flattened and slightly depressed posterior mesonotum, the absent lateral sc, the absent preapical bristles of mid and hind femora, vein M without bosse alaire. Though the facets of eyes do not have any soft hair and the surstylus is not complex, the two features are absent in some other genera of Medeterinae, too. For example, Medetera is bare between facets (
The new genus seems to have a wide tropical Oriental and Australasian distribution. It is actually known from Malaysia, Singapore, and Papua New Guinea. Daniel Bickel (pers. comm.) mentioned that it is present in Fiji as well. Since we did not see any differences between specimens of Protomedetera biconvexa sp. n. from Papua New Guinea and Malaysia, we consider them as conspecific for the moment. Similar consideration was taken on P. glabra sp. n., which distributes in both Papua New Guinea and Singapore. Molecular techniques will be needed in the future to support this conspecifity since such a disjunct distribution is very unlikely.
The authors thank Dr Olivier Missa, Dr Isabella Van de Velde, and Ms Jayanthi Puniamoorthy for collecting the specimens. Ms Kai Qing Chin (NUS) took the photograph of Protomedetera singaporensis sp. n. and did the NGS barcoding. We also thank Prof Rudolf Meier (NUS) for the lab facilities in Singapore. Precious advice from Daniel Bickel is deeply appreciated. The research was funded by the National Natural Science Foundation of China (31772497). The first author received a travel grant from the Royal Belgian Institute of Natural Sciences for her visit to