Notes on marine dolichopodid flies from Thailand (Insecta: Diptera: Dolichopodidae)

15 Pages·2001·0.88 MB·English

by  Grootaert, P

THE RAFFLES BULLETIN OFZOOLOGY 2001 49(2): 339-353
© National UniversityofSingapore
NOTES ON MARINE DOLICHOPODID FLIES FROM THAILAND
(INSECTA: DIPTERA: DOLICHOPODIDAE)
Patrick Grootaert and Henk Meuffels
DepartmentofEntomology, RoyalBelgian Institute ofNatural Sciences, Brussels, Belgium. [email protected]
ABSTRACT. - A preliminary report is given on the marine Dolichopodidae from the Thai coasts ofthe
AndamanSeaandthe GulfofSiam. Fifteenspeciesin7generaareidentified. Keys tothe generaandthe
species are provided together with short diagnoses to the species. Seven species are described as new:
Cymatopus thaicus, new species, Thinolestris thaica, new species, Thinophilus nitens, new species, Th.
parmatus, new species, Thinophilus setiventris, new species, Nanothinophilus hoplites, new species and
Phacaspis mitis, new species.
KEY WORDS. - Marine Diptera, Dolichopodidae, Southeast Asia, new species.
INTRODUCTION beachesandmangrovesalongtheAndamanSeaandtheGulf
of Siam. Our report is preliminary since our visits were
Insects are not reputed to have conquered the marine limitedtothedryseasonandonlyafewplaceswereexplored.
environment. Nevertheless, in tropical areas, the adults of Nevertheless, we found some unexpected genera such as
many species livein the supralitoralzone. Moreover, when Phacaspis, previously only known from the southern coast
the substrate is solid, such as rock or coral, many more ofPapuaNewGuinea, and Thinolestris, sofar onlyknown
species can even live as larvae in the intertidal zone. The fromPapuaNewGuineaandSulawesi. Inthepresentpaper
larvae ofthe chironomid genus Clunio are confined to the we describe new species in the genera Phacaspis,
sublitoral zone so that emergence of adults is necessarily Nanothinophilus, Thinophilus, ThinolestrisandCymatopus.
restricedtoperiodswhenthetidesareextremelylowduring
a spring tide. Specific fly communities live on rocky and Ashortsynthesisontheecologyofthevariousdolichopodid
sandy beaches while othercommunities are adaptedto live groups thatcanbefound onthecoastsoftheAndamanSea
inmangroves(Cheng, 1976).Quiteanumberofdolichopodid and the GulfofSiam is presented at the end ofthis paper.
flies have successfully adapted to these saline conditions,
and they are especially predominant in tropical regions.
Thailand is no exception to harbouring these flies and it MATERIAL AND METHODS
possesses a very rich halophilous dolichopodid fauna.
Unfortunately,fewreportsareavailableonthiskindoffauna. Materialwascollectedmainlybynetsweepingbutalsowith
white pan traps. The latter consisted of white rectangular
Grootaert & Meuffels (1998) published a paper on three plastic containers (18 x 13 cm and 5cm high). They were
speciesbelongingtothegenusNanothinophilus, whichwere placed on the ground and filled with 3 % formaldehyde in
found in mangroves along the coast of the Andaman Sea. water. Afew drops ofliquid soap were added to lower the
Anothershortnote(Grootaert& Meuffels, 1999)dealtwith surfacetension. Apartofsome dry mounted specimens, all
the rediscovery ofTerpsimyia in the GulfofSiam, a sofar specimenscollectedarepreservedin70%alcohol.Holotypes
monotypical genus, originally described by Becker (1922) and most paratypes are deposited in the collections ofthe
from Taiwan. Royal Belgian Institute of Natural Sciences (RBINS), but
voucher specimens of most species are deposited at the
In the present paper, we give a report on the communities Biology Department of Srinakharinwirot University in
of dolichopodids that were found during various visits to Bangkok (SWU).
Received 29 Nov 2000 Accepted 15 Feb 2001
339
Grootaert & Meuffels: Marine dolichopodid flies from Thailand
SYSTEMATIC ACCOUNT Wing: vein M interrupted about its middle, or somewhat
undulating and fading away about its middle. (in crab
burrows on sandy beaches; not reported yet from
Key to the male marine dolichopodids occurring in
Southeast Asia) Asyndetus
Thailand (females ofmost genera can be identified as
well with the key) 12. Male with very long lateral hairs on tip of abdomen,
hiding the genital capsule (cliffs, sandy beach) ..
1. Aristaapical;apairoffronto-orbitalbristlespresent(i.e.frons .......................................Terpsimyia semicincta (Becker)
withabristleateachside,halfwaybetweenbaseofantenna Male with 4 strong bristles on genital capsule.... Diaphorus
and vertex). Hydrophorinae, Aphrosylini 2
Arista dorsal, or subapical; no fronto-orbital bristles 5 13. VeinMnearwingtipstronglyconvergingtowardsveinr4+5
(intertidal zone ofsandy beaches; not reported yet from
2. Forelegstronglybristled,midandhindlegpoorlybristledor Thailand) Paraclius
without striking bristles. Usually fore tarsus shorterthan VeinMnotconvergingtowards veinr4+5 (only supralitoral
or as long as tibia (splash zone ofrocky shores) . ofsandy beaches; not reported yet from Thailand).........
......................................................................... Cymatopus . Dolichopus
Fore leg simple; otherlegs also simple, buthind leg may be
strongly haired or bristled. Fore tarsus clearly shorter
than tibia 3 Genus Phacaspis Grootaert & Meuffels, 1988
3. All legs in male simple, without strong bristles 4
Fore leg simple, hind leg with very long hairs at least Discussion. - This genus is represented inThailandwith 2
on tibia Cymatopus longipilus species: Ph. petiolata Grootaert & Meuffels and Ph. mitis,
new species. They consistofminuteflies about 1mm long
4. Snoutlong,firsttarsalsegmentofforelegveryshortandwith
found on the mud flats in mangroves.
a ventral notch (splash zone on rocky shores) .
.......................... Thambemyia
Snoutshorterthanheightofhead;costawithquitelong,spine
like bristles, longest near wing base (intertidal zone, on Key to the males ofPhacaspis in Thailand
pebbles and sand) Thinolestris
1. 3 dc; third antennal segment triangular, with acute tip; fore
5. First antennal segment dorsally bare 6 femurwithatleast4pvbristleslongerthanfemuriswide
First antennal segment dorsally haired. Dolichopodinae ..13 (Thailand) Ph. mitis, new species
- 4dc;thirdantennalsegmenttrapezoidalwithroundedtip;fore
6. Third antennal segment apically more or less rounded femur with a row of pv which are shorter than femur is
(somewhat kidney shaped in Diaphorinae, or almost wide (Thailand, PNG) .
circularin Thinophilus) 9 .................................Ph. petiolata Grootaert & Meuffels
Third antennal segment triangular in shape 7
7. Clypeuslentiform,eyestouchingabove and sometimeseven
Phacaspis mitis, new species
beneath c1ypeus. No acrostichal bristles present; 3
dorsocentrals 8 (Figs. 1-7)
Clypeus, parallel-sided; acrostichals uniseriate; (common
inmangroves;only 1speciesknownfrom sandybeaches) Materialexamined.- Holotype- male,Thailand: Krabiprovince:
.................................................................... Teuchophorus AoNang,mudflatatlowtideinmangrove(nearbridge,estuary),
coil. P. Grootaert, 24 Oct.I997 (sample nO. 97110).
8. No postocular hairs present; fore leg with tarsal
segments 2-4 short, at most as long as wide . Paratypes- 2males,2femalessameprovenanceasholotype;Trang
................................................................ Nanothinophilus province,Palian,mangrove,3males,2females,coIl.P.Grootaert,
Usual postocularhairs present; fore leg withtarsal segments 1 Nov.1997 (sample nO. 97152); Satun province, Pak Bara,
longer than wide Phacaspis mangrove, 3males, I female (sample 97133), 1male (samplenO
97134,colI.P.Grootaert,28Oct.I997; Singapore,Sungei Buloh,
9. Thirdantennalsegmentalmostcircular(aslongashigh)with 10males (samplen° 20032), coIl. P. Grootaert& N. Evenhuis, 6
a dorsal arista (very common on mudflats in mangroves, Oct.2000;Malaysia, SediliKecil, 1male(samplenO20047),coIl.
in supralitoral zone of sandy beaches, sometimes in P. Grootaert & N. Evenhuis, 12 Oct.2000.
sheltered areas on rocky beaches) Thinophilus
Thirdantennalsegmentgenerallyhigherthanlong(somewhat
Diagnosis. - A small species, resembling Ph. petiolata.
kindney-shaped) Diaphorinae 10
Thoraxwith3pairsofaboutequallylongdorsocentrals.Fore
10. Wing: tp absent; vein M not reaching wing border. Genital femurventrallywitharowofverylong, thin, straightsetae.
capsulewithoutstrongbristles.(mangroveorswampforest; Mid and hindfemora without longer hairs orbristles. Fore
not known yet from Southeast Asia) Cryptophleps
tibianearlyas longas femur, withoutbristles; midtibianot
Wing: tp present; vein M usually reaching wing margin.
thickened. Hypopygiumverylong,reachingbeyondbaseof
Genitalcapsulewithsomelongbristles(onsternum8)(in
Terpsimyia hidden by very long lateral hairs on tip of third abdominal segment. Basal antennal segments brown;
abdomen) 11 thirdantennalsegmenttriangular,withanacuteapex,longer
than deep.
11. Wing:veinMnormal,nearlystraight,notinterruptedorfading
about its middle 12
Male
Body length 1.1-1.2 mm; wing length 1.0-1.15 mm.
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THE RAFFLES BULLETIN OF ZOOLOGY2001
1
2
5
6
7
Figs. 1-7.Phacaspismitis,newspecies,paratypemale. 1.Antenna;2.Foreleg;3.midleg;4.Hindleg;5.Wing;6.Hypopygiumlaterally;
7. Hypopygium dorsally. Scale 0.1 mm.
341
Grootaert & Meuffels: Marine dolichopodid flies from Thailand
Head.Fronsandfacewithdarkmetallicgreengroundcolour. Head. Face nearly twice as wide as depth ofthird antennal
Face broad beneath antennae but rapidly narrowing segment. Tip of third antennal segment a little less acute
downwards; before middle of face eyes almost touching than in male.
(being separated by width ofan eye-facet), eventuallyface
Thorax. Alonghumeral,2notopleural, I sutural, I supraalar,
widening again, the clypeus being wide lentiform (as wide
nopostalar, Apairofscutellars;noacr, 3dc, almostequally
asthirdantennalsegment). Apairoflongdivergingocellars,
long.
a pair of long verticals inserted anteriad of the ocellars.
Fore leg. Coxaanteriorly with bristly hairs that are weaker
Antenna(Fig. I): basalsegmentsdarkbrown;thirdsegment
than in male, but as long. Femur ventrally withoutbristles,
yellowish brown, with apical half feebly darker. Third
with only short, very thin hairs.
segment triangular, 1.25 times as long as deep, with acute
apex. Arista dorsal, about 3 times as long as antenna, very Mid leg. Femur ventrally without short bristlets.
shortly pubescent; basalaristalsegmentshort, less thanone
Hind leg. No longer pv near tip.
third oflength ofthird antennal segment.
Thorax and scutellum with shining, dark metallic green Distribution. - Coast of Andaman Sea (Thailand).
ground colour. Noacr, 3aboutequally long dc. Firstdc the
longest. Scutellum with 2 marginal bristles. No propleural
bristle. Phacaspis petiolata Grootaert & Meuffels, 1988
Legs yellowish brown. Coxae I yellow with brown base,
Material examined. - Thailand: Prachuap Khiri Khan province,
coxae 11 and III brown. All femora dorsally browned,
Sam Roi Yot, mangrove, 1male, coil. P. Grootaert, 2 Apr.1996
ventrally pale yellow; all tibiae and tarsi brownish but
(sample n° 96002).
tarsomeres 1-4ofhindlegpaleyellowish, terminalsegment
dark brown. Discussion. - The specimen recorded here resembles the
speciesoriginallydescribedfromthesoutherncoastofPapua
Foreleg(Fig.2).Coxaanteriorlywitharowofshortbristlets.
New Guineainall characters and is therefore consideredto
Femur ventrally with a row ofabout 6, very thin, but long
be conspecific.
hair-like bristles, 4 ofwhich are longer than greatestdepth
offemur;moreanteroventrallyarowofshorterthinbristles.
Distribution.- CoralSea(PapuaNewGuinea),GulfofSiam
Tibia nearly as longas femur; ventrally arow ofvery short
(Thailand).
bristlets, shorter than diameteroftibia. Length oftibia and
tarsal segments (in mm): 0.3 : O.ll : 0.06 : 0.05 : 0.03 :
0.055.
Genus Nanothinophilus Grootaert & Meuffels, 1998
Mid leg (Fig. 4). Coxa without bristles. Femur simple,
ventrally with a row of very short, hairlike bristlets. Tibia
Discussion.- ThegenusNanothinophilusiscurrentlyknown
aboutas longas femur, withoutbristles.Lengthoftibiaand
only from the Andaman sea coast in Thailand. It is
tarsal segments (in mm): 0.41 : 0.16 : 0.07 : 0.06 : 0.05 :
representedby4species: N. armatusGrootaert& Meuffels,
0.06.
1988, N. pauperculus Grootaert & Meuffels, 1988, N.
Hind leg (Fig. 3). Coxa without bristles. Femur with a few dolichurusGrootaert&Meuffels, 1988andN. hoplites,new
short, hair-like pv near tip. Tibia about as long as femur, species.
withoutbristles,butwithslightlylengthenedhairs,especially
so in antero- and posterodorsal rows. Length of tibia and
tarsal segments (in mm): 0.41 : 0.11 : 0.08 : 0.06 : 0.04 : Key to male Nanothinophilus from Thailand
0.06.
I. Fore tibiae dorsally with at least 3 (seldom 2) or 4 (5) very
Wing (Fig. 5) hyaline. Apical partofml+2 nearly straight,
strong bristles 2
more or less parallel to r4+5. Tp short, much shorter than - Fore tibiae dorsally without strong bristles, at most bearing
apicalpartofm3+4(about I :4).Halterswhitewithagreyish some hairs 3
hue; squamae pale yellow with very short inconspicuous
2. Foretibiaedorsallywith3(seldom2)strongbentbristles.Fore
cilia.
femurventrallywithbristlesthatareaboutaslongasfemur
Abdomenshiningdarkmetallicgreen. Firstsegmentwithout is wide N. armatus Grootaert & Meuffels
sternum. Hairs and hind marginal bristlets on terga - Foretibiaedorsallywith4to5strongbentbristles.Forefemur
ventrally with bristles that are longer than femur
microscopic. Hypopygium(Figs.6,7)verylongandslender,
is wide N. hoplites, new species
pale yellow with brownish yellow base, reaching nearly to
base of abdomen. 3. Hypopygium less than half as long as abdomen.
Fore tibiae dorsally with some fine white hairs .
Female .............................N. pauperculus Grootaert & Meuffels
- Hypopygium more than halfas long as abdomen. Fore tibiae
Body length 1.2-1.35 mm; wing length 1.1-1.2 mm. dorsally with some brownish hair-like bristles ..
As the male, except: ................................N. dolichurus Grootaert & Meuffels
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THE RAFFLES BULLETIN OF ZOOLOGY 2001
Nanothinophilns hoplites, new species whicharelongerthandepthoffemur. Hypopygiumreaching
(Figs. 8-12) beyond base offourth abdominal segment.
Materialexamined.- Holotype- male,Thailand:Krabiprovince, Male.
Ao Nang, 24 Oct.l997, mud t1at in mangrove at low tide.
Body length 1.55-1.6 mm; wing length 1.3 mm.
Paratypes- Imale,2females,sameprovenanceasholotype,coil. Head. Fronsandfacewithdarkmetallicgreengroundcolour.
P. Grootaert (sample no. 97110).
Faceas inN. pauperculus, at its narrowestpointless broad
thandepthofthirdantennalsegment.Palpismall,yellowish,
Diagnosis. - LikeN. armatus, but fore tibia with a row of
with few, very short hairlets. Rostrum short, dark brown.
4-5 very longandstrong,bentbristles.Forefemurventrally
Chaetotaxyofheadas inN. pauperculus,butbristlesblack.
with bristles that are longer than diameter of femur. Hind
Antennayellow;apicalhalfofthirdsegmentfeeblybrowned.
femur ventrally with two irregularseries ofbristles, two of
Thirdsegmentaboutaslongasdeep,triangularwithrounded
8 9
12
10
11
Figs.8-12.Nanothinophilushoplites,newspecies,holotypemale.8.Foreleganteriorly;9.Hindleganteriorly; 10.Hypopygiumlaterally;
11. Hypopygium ventrally; 12. Cerci. Scale 0.1 mm.
343
Grootaert & Meuffels: Marine dolichopodid flies from Thailand
basalanglesandaratheracuteapex.Aristadorsal,morethan Discussion.- N. hoplitesiscertainlyverycloselyrelatedto
3 times as long as antenna, very shortly pubescent; basal N. armatus. Thenumberofstrongbristleson thefore tibiae
aristal segment halfas long as third segment. mightbevariableinthis speciesgroupbutthereare various
differences in the male genitalia as well. So, they are
Thorax and scutellum with dark metallic green ground
considered as distinct species.
colour, shining. All bristles black. No acr; 3 about equally
long dc. Scutellumwith 2marginals. No propleural bristle.
Distribution. - Coast of Andaman Sea (Thailand).
Legsandcoxaepaleyellow; midcoxaeexteriorlybrowned.
Fifth segment oftarsi not browned.
Foreleg(Fig. 8).Coxaanteriorlywithveryshort,finehairs, Genus Thinophilus Wahlberg, 1844
withoutbristles.Femurventrally withapartlydoubledrow
of hair-like bristles, that are longer than depth of femur; Discussion.- ThegenusThinophilusisverycommoninsun
dorsally an irregular row oflengthenedhairs. Tibia shorter exposed areas on the mud flats in mangroves and along
thanfemur (about3:4); dorsally arow of4-5 very longand creeks. It is less common on rocky shores and on sandy
strong, bentbrownish yellow bristles, the second one from beaches. Apart from the three new species described here,
baselongest, morethanhalfas longas tibia;onapical half, wesuspectthatmanymoremarinespeciesawaitdescription.
dorsally, two rows of hairs. Tarsus short; first segment
ventrally with a row of short bristlets. Length oftibia and
tarsal segments (in mm): 0.3 :0.1 :0.04 :0.03 :0.03 :0.05. Key to male Thinophilus ofThailand
Midleg. Coxawithoutbristles.Femurgentlybent,atapical
1. All coxae darkened; 20d tarsal segment of mid leg
fourth with a thin, hairlike anterior bristle. Tibia slightly
enlarged (Fig. 22) and darkened .
shorterthanfemur,feeblythickenedandmoreorlessspindle ............................................... Th. parmatus, new species
shaped; at apical fourth a weak, but rather long ad; some - Fore coxae yellow; tarsal segments ofmid leg simple .......2
hairs of the antero- and posterodorsal rows slightly
lengthened. Length of tibia and tarsal segments (in mm): 2. Wing spotted; 3'd abdominal sternum with a cluster
ofhairs Th. setiventris, new species
0.35 :0.15 :0.04 :0.04 :0.03 :0.05.
- Wing unspotted; 3cd abdominal sternum without a cluster of
Hind leg. Coxa without bristles. Femur (Fig. 9) feebly hairs Th. nitens, new species
narrowed and gently bent in basal half; ventrally, at apical
third, a long, stout bristle, and about middle a few shorter
bristles, hardly longer than diameter of femur; more Thinophilus setiventris, new species
posterodorsallyanirregularrowofbristle-likehairs,shorter (Figs. 13-16)
thandepthoffemur. Tibiashorterthanfemur,bearingalong,
thin, hairlike anterodorsal bristle at two thirds from base; Material examined. - Holotype - male, Thailand, Ranong
province, Ranong, Wat Tapotaram, river near hot springs, 5
hairsofantero-andposterodorsalrows slightlylengthened.
Apr.1996.
Length of tibia and tarsal segments (in mm): 0.4 : 0.11
0.07 :0.05 :0.04 :0.06. Paratypes- 5males,8females,sameprovenanceasholotype(leg.
P. Grootaert (sample nO 96025).
Wing as in N. pauperculus.
Abdomendarkmetallic green, with purplereflections. First Diagnosis.- Medium-sized,metallicgreenspecies,withdull
segment with sternum. Hairs and hindmargina1 bristlets on black spots on mesoscutum. Palpi brownish yellow. Legs,
tergamicroscopic. Hypopygium(Figs. 10, 11, 12)longand including fore coxae, yellow; hind tibia browned basally.
slender, pale yellow with brownish base, folded under Antennae yellow, dorsally browned. Legs poorly bristled;
abdomen, and reaching beyond base of fourth segment. forefemurof maleventrallywithirregularrowsofscattered,
EpandrialsetalongerthaninN. armatus.Bristlingandshape shortbristles, includingarow of 3to4longerpvonapical
of surstylus also different. third. Wing clouded on tp, on apical third of r4+5 and on
wing boss. Third sternum in male with a cluster of hairs.
Female
Body length 1.5-1.55 mm; wing length 1.2-1.5 mm. Male
As the male, except: Body length 2.8-3.5 mm(x: 3.15 mm); wing length2.3-2.7
mm (x: 2.5 mm).
Head. Face at middle about 1.5 times as wide as depth of
third antenna1 segment. Head.Fronsandfacewithshiningdarkmetallicgreenground
colour. Face at its narrowest point only a little wider than
Foreleg.Coxawithhairsalittlelongerthaninmale.Femur
the ocellar callus; clypeus much shorter than epistoma,
ventrally without hairlike bristles. Tibia dorsally with two
projecting. Palpi large, brownishyellow tobrown, setwith
rows of short bristles, all shorter than diameter oftibia.
sparse, short black hairs. Rostrum dark brown. Occiput
Mid leg. Femur with hairs ofanteroventral row somewhat shiningdarkmetallicgreen.2ocellars,diverging;2verticals,
lengthened; 1weakavatapicalfourth.Tibiasimple,without muchshorterthantheocellars,converging;2tiny, hair-like
bristles. postocellars;2postverticals,notinrowwiththepostoculars.
Hind leg. Femur and tibia simple, without bristles. Lateral and lower postoculars pale, pluriseriate. Antennae
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13 14 .-----;::.::..~~
15
16
Figs. 13-16. Thinophilus setiventris, new species, paratype male. 13. Fore leg posteriorly; 14. Hypopygium laterally; 15. Surstyli; 16.
Wing. Scale 0.1 mm.
short, yellow; all segments dorsally, andthirdsegmentalso Midleg. Coxawithablackexteriorbristle;anteriorlyamix
apically, broadly browned. Second segment encompassing ofshort blackhairs and bristles. Femur with 2-3 preapical
third segment partly on upper side, bearing very short pv. Tibia about as long as femur; 2 ad; a circlet of short
bristlets. Third segment rounded, about as long as deep. apicals. Length oftibia and tarsal segments (in mm): 0.92
Arista dorsal, practically bare, less than 3times as long as :0.55: 0.24: 0.16: 0.1: 0;11.
antenna;basalaristalsegmentveryshort,hardlylongerthan
Hind leg. Coxa with a black exterior bristle. Femur with 1
broad.
or2shortad, thatmay belacking. Tibiaalittle longerthan
Thorax and scutellum shining blackish green, with purple femur; 2 ad, 3 d, 2 v, all short; 4 apicals; at anteroventral
shine. Mesoscutum with a dull black spot in front of apicalrimashortfringe. Lengthoftibiaandtarsalsegments
scutellum, between the hindmost two pairs of dc, and (in mm): 1.2 :0.32 :0.3 :0.2 :0.1 :0.12.
roundishdullblackspotsabovewingroots; amedianglossy
Wing (Fig. 16)hyaline,slightlybrownishtinged, withvague
stripewidenes to the rear, to encompassthe dullblackspot
brownishcloudings ontp, apical third ofr4+5 and on wing
infront ofscutellum. Neckyellowish. Noacr. 6dc,thefirst
boss. Apical partofm1+2 with a slightupward bent (wing
ofwhich is small and hairlike, and the hindmost is a long
boss)justinfrontofitsmiddle,apicallyparalleltor4+5.Tp
andstrongbristle;the4dc in betweenthemarerathershort
aboutaslongasapicalpartofm3+4.Analveinpresent,short.
and all of about the same length. Scutellum with 2 strong
Halterspaleyellow. Squamaeyellowish,withshortpalecilia.
marginals, flanked each by a short hair. 3white propleural
Abdomendarkmetallicgreen, shining,withlargedullblack
bristles. Prothoracic collar with a row of white bristles.
saddle spots on anterior half ofterga. Sixth tergum bluish
Legsyellow. Forecoxayellow;midandhindcoxaebrownish black; fifth tergum with abluish gloss. Hairs and marginal
black,withyellowtips. Hindtibiabrownedatbase.Alltarsi bristles on terga short, black. Third sternum with a cluster
progressively browned on last three or two segments. ofblack bristly hairs on apical two thirds; fourth and fifth
sternaalso with arather long hairiness. Hypopygiumblack
Foreleg(Fig. 13).Coxaanteriorlywith2longblackbristles,
(Figs. 14, 15); cerci black, with short black hairs.
and, moretowards the innerside, witharowof3-4shorter,
thinblackbristles;atapexaslantingrowof4bristles.Femur
Female
with 3-5 pv on apical third; ventrally an irregular row of
weak, short bristles on basal half; a short dorsal bristlet at Body length2.8-3.8 mm(x: 3.45 mm); wing length2.5-3.1
theverybaseoffemur.Tibiaaboutaslongasfemur; 2dorsal mm (x: 2.85 mm).
bristles, a shorter one near base (sometimes reduced to a
Face about 1.5 times as wide as the ocellar callus. The pv
simplehair), andastrongeronejustbeyondmiddle;asmall
on apical third of fore femur very short or even nearly
ventralapicalbristle.Tarsalsegments 1-4withventralapical
lacking; no ventral bristles or hairs. Sterna of abdomen
spinules; first tarsal segmentventrally spinulose. Length of
without long hairs. Oviscapt with short black acanthae.
tibia and tarsal segments (in mm): 0.7 :0.3 :0.15 :0.12 :
0.09 :0.11.
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Grootaert & Meuffels: Marine dolichopodid flies from Thailand
Discussion. - This species may bethe sameas Thinophilus shortventral bristles. Wing hyaline, not clouded. Antennae
indigenus Becker, 1902, described from various localities yellow. Venter ofabdomen ventrally bare.
inEgyptandlaterreportedfromTainan(Taiwan)by Becker
(1922). Itisquitedoubtfulthatitconcernsthesamespecies. Male
In neitherpaper, Becker(l.c.) mentions long bristles on the
Body length 4.3 mm; wing length 3.4 mm.
sterna. A quite similarspecies was found in a mangrove in
Head.Fronsandface withshiningdarkmetallicgreenground
Singapore.Ithasaventralcombofspinulesontheforetibiae
colour,withcopperyreflections. Faceatits narrowestpoint
and the ventral bristling on the fore femora is also better
distinctly wider than ocellar callus. Clypeus much shorter
developed.Moreoveritdoesnotpossessaclusterofbristles
than epistoma, more bronze-coloured, feebly projecting.
on the third sternum like in Th. setiventris.
Palpilarge, yellow,withscatteredshortblackhairs.Rostrum
brownish black. Occiput shining dark metallic green. 2
ocellars, pointing upwards, diverging; 2 shorter verticals,
Thinophilus nitens, new species
pointing forwards, converging; no postocellars; 2 short
(Figs. 17-20)
postverticals, not in row with the postoculars. Upper
Material examined. - Holotype - male, Thailand, Ranong postoculars uniseriate, short, black; lateral and lower
province, Ranong, Wat Tapotaram, river near hot springs, 5 postoculars pluriseriate, not very long, whitish. Antennae
Apr.1996. short, yellow; second and third segments dorsally feebly
browned. Second segment encompassing third segment
Paratypes - 2 females, same provenance as holotype, coil. P.
partly on upper side, bearing tiny marginal bristlets. Third
Grootaert (sample nO 96025).
segment rounded, about as long as deep. Arista dorsal,
practically bare, about 2,5 times as long as antenna; basal
Diagnosis. - Large, metallic green species. Palpi yellow.
aristal segment very short.
Legs, including fore coxae, yellow. Fourth and fifth tarsal
segments ofmalefore and mid legs slightlybroadenedand Thorax and scutellum shining dark metallic green, with a
darkened.Forefemurofmaleventrallywitharowofbristles purplish shine. No dull black spots on mesoscutum. Neck
onbasalhalf,andposteroventrallywitharowof4-5bristles brownish yellow. No acr; 6 dc, the hindmostofwhichonly
on apical third. Mid and hindfemora ofmale with rows of is a long bristle. ScuteIIum with 2 large marginals, each
18
17
19
20
Figs. 17-20. Thinophilus nitens,new species,holotypemale. 17.Fore leg posteriorly; 18.Hypopygiumlaterally; 19. Surstyli; 20. Wing.
Scale 0.1 mm.
346
THE RAFFLES BULLETIN OFZOOLOGY 2001
flanked by a short hair. Propleura with a few white hairs, Face not much wider than in male. Fore femur has only a
twoofwhicharelong,andonebristle-like.Prothoraciccollar rowofshortpvonapicalthird.Midandhindfemorawithout
with a row of white bristles. ventralbristles.Midfemurwitharowofveryshortposterior
bristlets on apical two fifths; hind femur has a row ofvery
Legs yellow. Fore coxa yellow; mid and hind coxae dark,
short ad on apical half. Fore tibia: 2 ad, 2pd, sometimes a
with yellow tips. Fore and mid tarsi darkened from base of
weakventralbristle.Hindtibia: 3ad,3pd,2ventralbristles.
fourth segmentsonwards;fourthandfifth segmentsslightly
Oviscapt with short black acanthae.
broadened.Hindtarsusdarkenedfromtipofsecondsegment
onwards; fifth segment very feebly broadened.
Foreleg(Fig. 17).Coxaanteriorlywithwhitehairsandone
Thinophilus parmatus, new species
black bristle; at apex a row of5 thin black bristles. Femur
(Figs. 21-26)
ventrally, on slightly more than basal half, with a row of
about8thinblackbristles,all ofthemshorterthandiameter Material examined. - Holotype - male, Thailand: Phang-Nga
offemur; posteroventrallyonapicalthirdarowof4-5 short province:TakuaPa,river,estuary,coIl.P.Grootaert, 8May.1998
bristles.Tibiaaboutaslongas femur;2-3 veryshort,hairlike (sample nO 98031).
ad. Firsttarsal segmentventrallyspinulose;tarsal segments
Paratypes- 5males, 2 females ofsame provenance as holotype;
1-4 each with 2 apicoventral spinules. Fourth and fifth
Trangprovince,Palian, I Nov.1997, I male, 1female, mangrove
segments slightlybroadened, dorsallyrathershaggyhaired.
(sample n° 97152).
Lengthoftibiaandtarsal segments (in mm): 1.0:0.42 :0.2
: 0.14 : 0.1 : 0.15. Derivationominis.- Lat.parmatus, 'bearingasmallshield',
Midleg.Coxawithastrongblackexteriorbristle;anteriorly referring to the enlarged second tarsomere on the mid leg.
a rather long black hairiness, the hairs growing shorter
towards tip of coxa. Trochanter with a black ventral spot, Diagnosis.- Rathersmallspecieswithyellowpalpi,yellow
and3very smallanteriorbristlets. Femurventrallyonbasal antennae and all coxae dark. Male: second segmentofmid
twothirdswitharowofshortbristles;posteroventrally,about tarsusdorsallyenlargedintoadarkbrownlobe;thirdsegment
middleoffemur, arow of3-5 shortbristles; on apical third less widened, contrasting pale. 6-7 dc growing longer
someofthehairsoftheposteriorrow,andoneoftheanterior backwards, all relatively short. Cerci yellow; aedeagus
row, arebristlelike;asmallpreapicalpv.Tibiaaboutaslong without extension.
asfemur; 2adand2pd,formingpairsnearbaseandatmiddle
oftibia,allshort;acircletofapicals,includingaratherstrong Male
ventralbristle.Tarsalsegments 1-4eachwith2apicoventral Body length 2.3-2.7 mm; wing length 2.05-2.3 mm.
spinules.Forthandfifthtarsal segmentsslightlybroadened,
Head.Fronsandfacewithshiningdarkmetallicgreenground
dorsally rather shaggy haired. Length of tibia and tarsal
colour. Facerathernarrow, atitsnarrowestpointabouthalf
segments (in mm): 1.3 :0.8 : 0.26 : 0.18 : 0.11 :0.15.
as wide as depth of third antennal segment. Clypeus only
Hind leg. Coxa with a feeble, black exterior bristle. onethirdaslongasepistoma,broaderthanlong,protruding.
Trochanterventrallywithablackspot, withaventralbristle Palpi large, yellow, bearing scattered, very short black
and a few hairs. Femur ventrally with a row of very short bristlets.Rostrumlarge,blackish.Postcraniumshiningdark
bristles; dorsally nearbase someofthehairsarebristlelike; metallicgreen.2large,divergingocellars;2verticals(broken
ashortpreapicalav, andanequallyshortpreapicalpv.Tibia off); 2tiny postocellars; 2postverticals (brokenoff). Upper
about as long as femur; 3 ad, 2 pd, all short; 4 apicals; at postoculars uniseriate, black; lowerpostoculars very short,
anteroventral apical rim a short brownish fringe. Tarsal pale;lowerpostcraniumwithveryshort,palehairs.Antenna
segments 1-4each with 2apicoventral spinules. Fifthtarsal short, yellow; upper margin of third segment narrowly
segmentvery slightly broadened. Length oftibiaand tarsal brown. Secondsegmentnotencompassingthirdsegmenton
segments (in mm): 1.65 :0.5 : 0.38 : 0.27 :0.15 :0.17. upper half, with very short, pale marginal bristlets. Third
Wing (Fig. 20) hyaline, feebly brownish tinged, without segmentshort, rounded, with long, pale pubescence. Arista
cloudings. Apical part of ml+2 gently curved (wing boss) subapical, black, about twice as long as antenna, with
beforeitsmiddle,apicallyparalleltor4+5.Tpaboutaslong microscopicpubescence;basalaristalsegmentyellow, very
as apical part of m3+4. Anal vein present. Halters pale short.
yellow. Squamae pale yellow, with pale cilia. Thorax and scutellum shining dark metallic green, with
Abdomenbeautifullyshiningdarkmetallicgreen,sidewards bronzeandpurplishreflections;betweentherows ofdcdark
bluish, dorally on terga 1-4 more bronzy, on terga 5 and 6 twodarklongitudinalstripes,reachingbackwardstolastbut
morebluish-greenandpurplish; incisionsbetweentheterga onepairofdc.Noacr.6-7dc,allrathershort,growinglonger
hardlydulled.Hairsandmarginalbristlesontergaveryshort, backwards.Scutellumwith2marginals,withoutlateralhairs.
black. Venter bare. Hypopygium (Figs. 18, 19) blackish, Propleuraewithafewveryshorthairs [bristles?,brokenoff].
folded in under terga 5 and 6, its tip reaching nearly the Legs.Allcoxaedark;foreandmidcoxaewithgreenishgloss;
anterior margin ofthe fifth abdominal segment. hind coxa usually paler, brownish. Legs yellow; fifth
segmentsofalltarsifeeblybrowned.Enlargedsecondtarsal
Female segment of mid leg dark brown, third segment yellowish
Body length 4.4-5.3 mm; wing length 3.9-4.1 mm. white.
347
Grootaert & Meuffels: Marine dolichopodid flies from Thailand
Fore leg (Fig. 21). Coxaanteriorly withtwo irregularrows with two irregular rows of short, thin bristles, longest on
of short black hairs and bristles, growing slightly longer basal halfoffemur (bristles ofthe more anteroventral row
downwards; at apical rim a few short, black, bent bristles. longest, slightly longer than half a diameter of femur); a
Femurventrallywitharowofshort,hairlikebristles,longest preapicalpv.Tibiaslightlylongerthanfemur; 2short,weak
near base (hardly halfas long as depth offemur); a small adonbasalhalf; 1small,weakpv(notalwayspresent);some
preapicalpv. Tibiaaboutas longasfemur; ventrally witha apicalbristles,the2ventralonesratherstrong. Secondtarsal
row of short bristles, as long as or slightly shorter than segment(Fig. 22)dorsallyenlargedintoadarkbrownlobe,
diameter of tibia; no dorsal bristles. Tarsal segments 1-4 bearing rather long bristly hairs dorsally; third segment
ventrally 'prickly' asaresultofrowsofshortbristlets.Length broadenedatbase,taperingtowardsitstip(Fig. 22).Length
oftibiaandtarsal segments (inmm): 0.8 :0.43 :0.15 :0.12 oftibiaand tarsal segments (in mm); 1.1 :0.5 :0.17 :0.15
:0.09 :0.1. :0.1 :0.11.
Mid leg. Coxaanteriorly with afew short, hairlikebristles; Hind leg. Coxa with a black exterior bristle. Femur (Fig.
attiparowofclose-set,short,bentbristles.Femurventrally 23)ventrallywithscattered, short, verythinerecthairs, one
-- --
----
21 \\\ \ \ \
24
25
26
Figs. 21-26. Thinophilusparmatus, new species, paratypemale. 21. Foreleg posteriorly; 22. Mid tarsus; 23. Hindfemur; 24. Aedeagus
and surstyli ventrally; 25. Hypopygium laterally; 26. Surstyli. Scale 0.1 mm.
348