First record of the genus Myrmica (Hymenoptera: Formicidae) from Northern Vietnam, with a description of two new species

5 Pages·2001·0.27 MB·English

by  Radchenko, A. G.

ANNALES ZOOLOGICI
(Warszawa),2001, 51(2): 221-225
FIRST RECORD OF THE GENUS MYRMICA (HYMENOPTERA:
FORMICIDAE) FROM NORTHERN VIETNAM,
WITH A DESCRIPTION OF TWO NEW SPECIES
W
ALEX.4NDER G. Radchenko' and Grailam Elmes2
'Miisrinii (imI Institute of ZooUMjtj, PolisJi Acadc/u// of Sciences. Hi. W'ilezn stn, OO-li'f).
Warsdir. Poldiid/Institute ofZooJooj/ ofnnriiiu'aii \'<i1ioiKitAcculeiiii/ ofScieiu-es. 15. B.
KliDieliiitsJi-}/str..Kier-SO. 2r)2()01. Ukraine:e-iiiait: mct(<iiiseiic.t,-ier.iia
-'('EH Dorset. Wi)tfritli Teclniologj) Centre. Winfrit/i Xewbnrg. Dorcliester. Dorset UT2 HZD.
UnitedKinz/dom:e-niait(/irvCaeeli.ac.n/i
—
Abstract. Two i\qwMi/rwico species (J/, titciiiica and.1/. ,i/a>nai/ei) are described from
tlie mountains ot Nortliern Vietnam, and their taxonomic status is discussed. .Also, the first
report of.1/. sericei from Metnani and a newreport o!M. ritae from Thailand are I'ecorded.
—
Key words. .Ants, Formicidae, Mijrniica, M. titeiuica, M. i/aiiKniei, taxonomy, new
species, \'ietnani.
Introduction Emery (Northern Thailand, Doi Inanthon National Park,
near Chaing Mai, 20.viii.l998, leg. S. Yamane, in rotten
Mjli'ttiicd species ntainly live in the Temperate Zone wood); this is only the third report of a species first col-
oftheHolarcticRegionbut somearefoundon mountains lected in 1889 (see Radchenko and Elmes 1998, 1999).
in tlie northern parts of the Oriental Region. These
include many species from the ritae species-group of Methods
Mi/rttiicd. which is distributed from Taiwan to
Himalayas, including southern China, northern Burma Wetookmeasurements ofthe three specimens (using
and Thailand (Radchenko and Elmes 1998, 1999; Elmes a graticule accurate to 0.01mm) which can be compared
and Radchenko 1998). Worker.s and queens ofthe ritae- with data for other species published byRadchenko and
gToup differ from other Palaearctici////7?//c« by a vari- Elmes (1998). As in that paper, we use the following
ety of morphological features, particularly by very long abbreviations for morphometries and indices.
propodeal spines, a long and low petiole, a fig-shaped
postpetiole, and a longantennal scape (which is weakly Morphometries
cuned at the base and usuallylonger than head). HL- length of head in dorsal \iew', measured in a
Recently, Prof. Seiki Yamane sent us someMyriitica straight line from the anterior point of median
samples, collected in Northern Vietnam; these were the clypealmargintomid-point oftheoccipitalmargin
first records ofgenusMtjfititea fromVietnam. The sam- HW- maximum width of head in dorsal view behind
ples included three species, all of which belong to the the eyes
rttdc-group. There were 2 workers ofMi/n/iico serica FW- minimumwidth offronsbetw^een thefrontallobes
Wlieeler (Xeo Mi Ti, 1680 m.. Sa Pa, Lao Cai, northern FLW- maximumwidth between externalborders ofthe
\letnam, 29-3().\ii.l998, leg B. TViet). These specimens frontal lobes
showed minor differences from txTjicalM. .serico, which SL - maximum straight-hne length of antennal scape
were insufficient to warrant describing a new species: seen in profile
furthermore, M. serica appears to be relatively wide- .AL - diagonal length of the alitrunk seen in profile,
spread in adjacent southern China (Radchenko and from the neck shield to the posterior mai-gin of
Elmes 1998). Three workers were sufficiently different metapleural lobes (workers) and from the ante-
from all other kno\Mi sjjecies from the /7Yr/('-grou]D for rio-dorsal point ofalitrunk lo posterior margin of
them to be described as new for science (below). In addi- metapleural lobes (queens and males)
tion. Prof. Yamane sent (3 workers of Mz/rinica ritae HTL - length of tibia of hind k>g
222 A. G. Radchenko ond G. W. Elmes
PNW- maximumwidthofpronotumfromaboveindorsal Indices
\iew (workers)
PL - maximum length ofpetiole from above Cephalic
PPL- maximum length ofpostpetiole from above
PW- maximum width ofpetiole from above
PPW- maximumwidth ofpostpetiole from above
PH - maximum height ofpetiole in profile
PPH- maximum height ofpostpetiole in profile
ESL- maximum length ofpropodeal spine in profile
ESD- distancebetweentipsofpropodealspinefromabove
SCW- maximum width of scutum from above (queens
and males)
SCL - length ofscutum+scutellum from above (queens
and males)
AH- height of alitrunk, measured from upper level of
mesonotum perpendicularly to the level of lower
margin ofmesopleurae (queens and males)
MYRHIKA OFVIETNAM 223
224 A. G. Radchenko and G. W. Eimb
12
gs^ 5?^^
Figures8-l2. Details ofstruclure olMuniiica natiKuiei (holoU-pe.worker). (8) Head, dorsalview, (9) anteniial scape in profile, (10) alitrunk and
waist inprofile, (U) samefromabove, (12) tibiaofliindleg. Scalelineforallfiguresequal to 1 mm.
Spurs on middle and hind tibiae well developed and dis- Discussion
tinctly pectinate.
WTiole body with very coarse sculpture. Frons Both new species clearly belong to the /v'tof^-gToup.
between frontal carinae level with the eyes with six Despite its size, on all principle features M. titunicd
rugae. Onlyfrons andgenaewithsinuous rugae, remain- belongs in the r/taf'-complex (Radchenko and Elmes
der of head dorsum with coarse reticulation; clypeus 1998), particularlybythecoarse rugosityoftheheadand
with coarse longitudinal rugae; mandibles striato-rugu- alitrunk, and the smooth surfaces between rugae on the
lose; frontal triangle smooth and shiny. headdorsum. Except iovMyrmlca angulata Radchenko
Alitrunk dorsum very coarsely reticulates, sides of et ul. 2001, M. titanica differs from all other species of
pronotumwith reticulation, mesopleurae and lower part the r/taf'-complex by the punctures of the surfaces
of propodeal sides with rugae; petiole and postpetiole between rugae ofthepetiole and postpetiole. However, it
withcoarse concentricrugae. Surfaces ofhead, alitrunk, clearly differs fromM. angulata which has scapes that
petiole and postpetiole between rugae superficially but are sharply curved at their base, by its much larger size
distinctly punctured, appearing dull (but punctures of and gradually cur\'ed scapes (also compare measure-
pronotum somewhat reduced); gaster smooth and shiny ments and indices with those in Radchenko et at. 2001).
Numerous outstanding hairs present on head margins; Superficially, it most resembles the previously largest
hairs onalitrunkverylong; hairs ofantennal scapes and knownMyrtnica species,if.gigantea (ColUngwood),but
tibiae subdecumbent. Colour of alitrunk and head dark is much larger than that species (HW > 1.80 mm versus
reddish-brown, gaster brownish-red, antennae and legs < 1.65mm;HL > 2.10mm v < 1.90mm;AL > 3.30mm r
yellowish-red. < 2.60 mm). M. titanica also has much longer erect to
Queens, males and ecology are unknown. suberect hairs onantennal scape and tibiae comparedto
Types. Holotypeworker. Northern Vietnam, Lao Cai, M. gigantea. Furthermore, comparison of the various
Sa Pa, Xeo Mi Ti, alt. 1680 m, 29-30.vii.1998, leg. B. T. indices (Table 1) with those for M. gigantea holotype
Viet. Holotype in collection of S. Yamane (Kagoshima (RadchenkoandElmes 1998) andthesecondfoundwork-
University- see acknowledgement). er (Radchenko and Elmes 1999), shows thatIf. titanica
Etymology. This species is dedicated to the has relativelylonger scapes (SIl 0.98 v 0.89), arelatively
Japanese myrmecologist Prof. SeikiYamane, who kindly shorterpetiole (PIl 1.13v 1.55 andPI20.55 v 0.48), arel-
sent us material for investigation. ativelylonger,higherbutnarrowerpostpetiole (PPIl 1.16
MYRMICA OF VIETNAM 225
r 1.06; PPI3 1.33 v 1.43), relatively longer spines (ESLI bly many more /vYf/f-group species endemic to particu-
0.46 r 0.35) andlegs (HTI 1.21 v 1.05). lar mountain systems in northern Burma, Thailand,
The taxonomie position of the M. yomanei is less Laos and Vietnam, and of southern China, yet to be dis-
clear While it clearly belongs to the /v'to^^-group, it covered (Radchenko and Elmes 1998).
shares features of both the ritae- and 6o/^o///-complex-
es (Radchenko and Elmes 1998). The fto/to^//-complex Acknowledgements
differs from the /77«r^-complex by a much more finely
rugose or even striated head and alitrunk, a punctured We are sincerely gi-ateful to Prof. Seiki Yamane
(not rugose) waist, and a head dorsum with distinctly (Department of Earth and Environmental Sciences.
punctured surfaces between the rugae.M. jicniKtnei has Faculty of Science, Kagoshima University, Koi'imoto
thecoarse sculpture ofthewholebodywhichistypical of 1-21-35, Kagoshima, 890-0065, Japan) who sent us his
the r//o('-complex (based on this feature we assign it to material ofthe species considered above.
that complex), but the surfaces between rugae have the
punctures that are tj'pical in the ?^o/to/?/-complex. This References
unusual combination of features well discriminates M.
il<nn(ni('i from any known species from the ritne-gvo\i\i Elmes,G.W. andA. (i.Radchenko. 1!)9S..AntsofthegenusMi/niiicd
except torJ/, draco Radchenkoet al. 2001. It differs from from Taiwan (Hynienoptera, Formieidae). Chinese Journal of
M. draco byitswell-developed, coarse, reticulated sculp- Entomology, 18:217-2:24.
ture of the head dorsum and by the punctures on sur- Radchenko, A. G. and (i. W. Elmes. 1998. Taxonomie I'evision ofthe
r/'tdc species group of the genus .Ifi/n/i/ca (Hymenoptoi'a,
faces betweentherugaeofthealitrunk (compareFigs. 8, Fofinicidae). \'estnikZoologii. 32: 3-27.
10, 11 with Figs.ll, 13, 14 in Radchenko et al. 2001). Radchenko, A. G. and G. W. Elmes. 1999. First description of the
The fact that a small number of samples from the femaleofMi/rni/ca ritae(Hynienoptera,Formieidae),withsome
mountains of northern Vietnam produced examples of notesonthe/77«^'-gToup. Vestnik Zoologii. 33: 9,5-98,
Radchenko, A. G,, S. Zhou and G, W. Elmes, 2001, New and rai'e
three species from the r//«(^-group olMijriinca provides
Mijriuk-(t species (H\inenoptera, Eoi'micidae) from Southern
furtherconfirmation ofouropinion that there are proba- China,Annates Zoologici, .t1: 211-219,
Received: .March30,2001
.Accepted: May20,2001