A new species of Hanseniella (Symphyla: Scutigerellidae) from the interior highlands of Arkansas

6 Pages·1992·1.7 MB·English

Vol. 103,No. 5,November&December, 1992 169
ANEW SPECIES OFHANSENIELLA (SYMPHYLA:
SCUTIGERELLIDAE) FROM THE INTERIOR
HIGHLANDS OF ARKANSAS
1
RobertT.Allen2
AweBsSteTrRnAACrTka:nsHaasn.seTnhieelnlaewousapcehciiteischias,monsetwclsopseecliyesr,eliastdeedstcor//i,bevdanfdrykoemiRfircohmCMaoluinfotraniina.iAn
keytothethreeknown North Americanspeciesisgiven.
Edwards(1990) has pointedoutthat Symphyla are"extremelycom-
mon inhabitantsofsoil in all partsoftheworld."butthat"thescientific
literatureonthegroupisnotvoluminous."Bothstatementsarecertainly
trueofthisclassofarthropodsinNorthAmerica. Edwards(1990)indis-
cussing the morphology and ecology ofthe Symphyla also rendered a
valuable service to those wishing to work with this group by providing
keystothetwoNorthAmericanfamiliesandtheNorthAmericangenera
recognizedineach family.ThegenusHanseniella Bagnallbelongstothe
familyScutigerellidae.Thispaperdescribesanewspeciesandpresentsa
key to the three North American species ofHanseniella.
ThesymphylidgenusHanseniellaoccursonallthecontinentsexcept
Antarctica.Thegenusismostdiverseintropicalareas.Onlytwospecies,
H. californica Hilton (1931) and H. vandykei Michelbacher (1939), are
known from North America, both species recorded only from Califor-
nia.ThispaperdescribesanewspeciesfromtheOuachita Mountainsof
western Arkansas.
1 ReceivedJanuary22, 1991.Accepted September3, 1991.
- Department of Entomology and Applied Ecology, University of Delaware. Newark.
DE. 19717-1303.
ENT. NEWS 103(5): 169-174,November& December, 1992
ENTOMOLOGICALNEWS
170
Key to the North American Species ofHanseniella
1. Tarsalclawsunequal(Fig.21),oneclawmuch longerthan theother 2
Tarsalclawsequal califomica Hilton
2. Proximal segmentoffirstpairoflegswith onelongprominentseta;21-26antennal
segments;central rodofheadcontinued anteriorly vandykeiMichelbacher
Proximal segment of first pair oflegs with three prominent setae (Fig. 24); 16-25
antennal segments, usually 19, 20, 21; central rod ofhead notcontinued anteriorly
(Fig. 1) ouachiticha newspecies
Hanseniella ouachiticha, new species
Holotype:Arkansas,PolkCounty,RichMountain,EagletonOverlook,17February1988,
CMC
extractedwithBerlesefunnel,RobertT.Allen,collector.Slide-mountedin medium,
deposited in theAmericanMuseum ofNatural History,NewYork(AMNH).
Paratypes. 79slide-mounted (CMC medium)specimens, samedata asthe holotype; 10
specimens. University ofArkansas Arthropod Collection (UAAC); 5 specimens United
States National Museum (USNM); 5 specimensAMNH; 59specimens, RobertT.Allen
Collection(RTAC).
Etymology.ThisspeciesisnamedaftertheOuachitaMountains,amajorsubsegmentof
theInteriorHighlands.
mm
Length.2.5-3.0 (apexofheadtoapexoflastabdominal segment).
Head(Fig. 1).General: slightlywiderthanlong,setaepresentovertheentiresurface,all
aboutthesamelengthandsize,exceptforthesetaealongtheposteriormarginsofthescuta.
Centralrod:weaklydevelopedposteriorly,notevidentinallspecimens;lateralbranches
sometimesevident,extendingtowardthepostantennalorgans.Mandibles(Fig.6):visible
inmostspecimens;themandibleisalargeenditeapparentlycomposedoftwoparts,the
outerlobebearingfourdistinctteeth,theinnerlobewithanumberofindentationsnotas
deep ordistinctas those in theouterlobe. Postantennal organ; small, notevidentin all
specimens.
Antennae.(Figs.7,14)Numberofsegmentsvariablerangingfrom 16-25,butmostcom-
monly19,20,21;segments1-3usuallywithonewhorlofsetae;twowhorlsonsegments4-10,
sometimeson 3 aswell; othersegments with threewhorls,startingwith segment 11; ter-
minal segmentwith the usual three-stalked "sensory" structure; othersegments without
evidentsensoryorgans.
Scuta.(Figs.2-59-13, 17-20)Posteriormarginsofscutastraightoronlyweaklyconcave.
The following "table" enumerates the number of setae found along the posterior
marginofScutaI-XTV.TheShortSetaearethosebetweentheLongLateralSetaeorallthe
posterioron ScutaV,VII,andXI.
ScutaNo.
Vol. 103,No. 5,November& December. 1992 171
0.5mm
Figures 1-8.Hanseniellaouachiticha: 1.head;2-5,scuta 1 to4respectively;6.mandible;7,
antennal segments 1-6; 8,stylus,coxalsac andcoxaofleg 10.
ENTOMOLOGICALNEWS
172
Figures9-16.Hanseniellaouachiticha.9-13,scuta5to9respectively; 14,distalfourantennal
segments; 15,spinneret; 16,trichobothriumvesicle.
Vol. 103,No. 5,November&December, 1992 173
at /V hJ.If. 1
M;,':',
~ J4ff444k c^-J
.-.yLy ,.f.-^4J'
Figures\l-25.Hanseniellaouachiticha. 17-20,scutalOto13respectively;24.tarsusandclaws
ofleg10;22.coxaofleg10;23,femurandtibiaofleg10;24.proximalsegmentofleg1 show-
ing3 prominentsetae.
ENTOMOLOGICALNEWS
174
Legs.Legsegmentsclothedwithadensecoveringofsmallpilosehairs.Firstpair:halfthe
lengthofthesecondpairoflegs;proximalsegmentwiththreedistinctprominentsetaeon
theanteriorsurface,distal segmentwith two rowsofthreeprominentsetaeeach on the
anteriorsurface.Legpairs2-9;tarsiwithtworowsof3-5prominentsetae(Fig.21);tibae,
femora,andtrochanterswithavariablenumberofprominentsetae.Legpair10(Fig.23):
tarsi with two rowsof4prominentsetae, sometimes alsowith 2-3 additional setae near
theserows;tibiaandfemorawithavariablenumberofprominentsetae.Claws:(Fig.21)
unequal,oneclawhalforlessthan halfthelengthoftheotheron alllegs.
Styli.(Fig. 8)Welldeveloped,presentatthebaseoflegpairs3-11.
CoxalSacs(Eversiblevesicles)(Fig.8).Distinct,presentatthebaseoflegpairs2-11;the
sacappearstobecomposedoftwo"sclerotized"areas,each with2-3 prominentsetae.
Trichobothria(Fig. 16). Setaealmostaslongasthespinneret;ventral marginoftricho-
bothriumvesiclewith7-8prominentsetaeintheproximal1/2-3/4;distal1/4withonlyone
longprominentsetaetowardstheapex.Innerapicalmarginwithaseta 1/2aslongasbody
ofthespinneret;outerapical marginproduced intoan acutespine-likeprocess.
DISCUSSION
Hanseniellaouachiticha appears to be most closely related toH. van-
dykei. The newspecies differs from H. vandykeibythe characters given
inthe key,i.e. a fewernumberofantennal segments,proximal segment
offirst pairoflegs with three prominent setae ratherthan one, and the
veryshortcentral rodofthehead. In addition theproximal legsegment
ofthe first pair oflegs is elongate in H. ouachiticha and short, almost
square, in H. vandykei.
ThetypelocalityforthenewspeciesisonRichMountain,thehighest
feature(about2,750feet)in theOuachita Mountains. All the specimens
were found in a single Berlese sample taken from rotting logs and at
the base ofrotting stumps. This mountain is also the type locality for
two species ofendemic earth worms, a freshwater amphipod, and the
Rich Mountain salamander.
LITERATURECITED
Edwards, C. A. 1959, Keys to the genera of the Symphyla. Journ. Linn. Soc. Zool.
44:164-169
Edwards,C.A.1990.Symphyla.Chapter28.inSoilBiologyGuide,ed.D.L.Dindal,John
Wiles&Sons,NewYork.
Hilton, W. A. 1931. Symphyla from North America. Ann. Entomol. Soc. Amer. 24:537-
553.
Michelbacher, A. E. 1939. Further notes on Symphyla with descriptions ofthree new
species from California.Ann. Entomol. Soc. Amer. 32:747-757.