Hincks,W. D.

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CORYNDON MEMORIAL MUSEUM EXPEDITION TO
THE CHYULU HILLS.
IX. DERMAPTERA.
By W. D. HINCKS,F.R.E.S.
The Earwigscollectedby the Expeditionandsubmittedfor
studyby Mr. A. F. J. Gedyecompriseforty-ninespecimensof
four species,2 of which are representedby singleexamples.
One species,Echinosomawahlbergi is a widely distributed
African form known from PortugueseGuineain the west to
Abyssiniain the eastand southto the Cape. The remaining
speciesare muchmorerestrictedin range,two at leastbeing
recognisedcomponentsof a smallbut interestingalpinefauna
associatedwith the mountainrangesand massifsof Tropical
Africa. For informationon this subject,limitedas the known
datais, referenceshouldbe madeto the papersof Burr (1907,
Kilimanjaro),Menozzi (1938,East Africa), and Hincks (1938,
MufumbiroVolcanoes).
Little can be saidof the habitsor biologyof any African
Dermapteraand greatindeedis the needfor observationsand
dataof eventhe mostelementarykind.
SuperfamilyLABIDUROIDEA.
Family PYGIDICRANIDAE.
SubfamilyECHINOSOMATINAE.
ECHINOSOMA WAHLBERGI Dohrn, 1863.
EchinosomawahlbergiDohrn,StettinEnt. Zeitschr.,24, 1863:
64, o. (Caffraria.)
EchinosomadistantiBurr, in DistantIns. Transv., 1910:252,
fig. 48, o. (Transvaal)
Chyulu Hills, alt. 5,600ft., June, 1938,10.
Although this widely-distributedspecieshas not always
beencorrectlyidentifiedby previousauthorsthemaleis readily
recognisedby the lateralkeelsof abdominaltergitesV andVI
andthelongandconvolutedvirgaof thegenitalia.Thetruncate
but not transversepygidiumdistinguishesthe female.
Despiteinaccuraciesin therecordsE. wahlbergiis certainly
very widely distributedin Africa. Basedon the literaturethe
followingis the recordedrange: PortugueseGuinea,Liberia,
Togo,Cameroons,FernandoPo, FrenchCongo,BelgianCongo,
Angola, Uganda, Abyssinia, Kenya, Tanganyika, Zanzibar,
Mozambique,Zululand,Natal, Transvaaland CapeColony.
33
The Chyulu male agreesperfectly with material from
BelgianCongoin my collection.
Family LABIDURIDAE.
Subfamily PSALIDINAE.
GELOTOLABIS FELIX (Burr, 1907). (Fig.!.)
Anisolabis felix Burr, in SjostedtKilimandjaro,Orth., 17, 1907:
4, pI. 1, fig. 4, 4a. 09. [Kilimanjaroca. 3,000m. (approx.
10,000ft.).]
Horridolabis paradoxura Zacher,Zooi. Jahrb., 30, 1911: 384,
figs.V, M2. O. (Kenya: Kikuyu Escarpment.)
Chyu'luHills, alt. 5,600 ft. (approx.1,700m.), July,
1938,10.
The speciesgroupedunder the name Gelotolabis are a
specializedbranch of the cosmopolitangenusAnisolabis and
the statusof the manydivisionsof the latter is still debated.
This is a very interestingspeciesregardedas one of the
African montaneforms and was first recordedfrom about
10,000ft. on KilimanjarowhenceBorelli (1915)hassincenoted
it at variousstationsand also on Mt. Kenya. Menozzi(1938)
has recordsfrom Mt. Elgon 3,500m. to 4,000m. (approx.
11,500ft. to 13,000ft.), Mt. Marakwetabout3,426m. (approx.
11,500ft.), Mt. Kinangop 3,500m. to 3,700 m. (approx.
11,500ft. to 12,200ft.), andMt. Aberdare2,900m. to 3,100m.
(approx.9,500 ft. to 10,200ft.). He statesthat G. felix is
characteristicof thealpinezoneover2,500m. (approx.8,200ft.).
It will be seenthat of the localitieswherealtitudesare noted
the presentrecordrepresentsthe lowest limit at which the
specieshasyet beenfound. Burr (1912),however,hasa record
"LoangwaRiver, Mpeta." It is presumedthat this refersto a
NorthernRhodesialocality. TheLuangwaRiver is in thenorth-
easternpart of this territory and to its west is Mpika which
may be the locality intended.There is, however,a Loangwa
River in thenorth-west,flowingintoLake Mweru,but I cannot
traceMpetain this area. Zacher'stype locality is the Kikuyu
Escarpmentin Kenya (8,200ft.), no altitudeis, however,stated
in the originalcitation.
Additional unpublishedKenya recordsfrom altitudesof
over 9,000ft. will be givenin a forthcomingpaper.
The genitaliaof the male specimenare here figuredfor
comparisonwith Zacher'sillustrationreferredto above.
SuperfamilyFORFICULOIDEA.
Family LABIIDAE.
SubfamilyLABIIN AE
34
3I
5
FIG. 1.
FIG. 2.
FIG. 3.
FIG. 4.
FIG. 5.
EXPLANATION OF FIGURES.
(brawn by the writer with the aid of a squared eyepiece; the scale
against each represents approximately half a millimetre.)
Malegenitaliaof Gelotolabis felix (Burr). (Paramereshrunken,
donotshowcharacteristicshapedespitetreatmentwithKOH.)
Malegenitaliaof Chaetospania rodens Burr.
Portionof apicalsegmentsof maleC. rodens showingpygidium
andpart of onelimb of forceps.
Part of penultimatesterniteof maleC. rodens showingmanu-
brium.
Portionof apicalsegmentsof femaleC. rodens showingpygidium
andpartof onelimbof forceps.
35
CHAETOSPANIA RODENS Burr, 1907. (Figs. 2 to 5.)
ChaetospaniarodensBurr, in SjostedtKilimandjaro, Orth.,
17, 1907:7, pI. 1, fig. 5. 69. [Kilimanjaro, Kibonoto
(cultivatedzone)1,300m. to 1,900m. (approx.4,400ft. to
6,300ft.).]
Chyulu Hills, 5,200ft. to 6,000ft., April-July, 1938,
566, 599, 2 juv. [April 19, 1 nymph,5,200ft.;
May 1 nymph,5,400ft.; June 266, 19 (damaged),
5,600ft.; July 16,5,600 ft., 266, 399, 6,000ft.]
Lengthincludingforceps6, 9 mm. to 12mm.; 9,
9 mm. to 11mm.
Hithertothis specieshas not beenrecordedfrom Kenya.
All previous records are from Tanganyika,mostly in the
Kilimanjaro area,exceptfor a singlenote by Burr (1912)of
a specimenfrom Ukaika-Mawambin Belgian Congo.
Probablymostof the reportsof this insectare from high
altitudes,but that this is not entirelythe case,is evidentfrom
Burr's (1907B)Amani record.
One malein the presentseries(July, 6,000ft.) is interest-
ing in havingthewingsreducedto suchan extentasnot to be
visiblebeyondthedistalmarginof thetegmina.This specimen
is ratherslendererthantheothersandtheabdominalpunctura':'
tion appearsheavier. The latter character,however,variesto
someextentin the seriesalthoughit is alwaysstrongerin the
male than the female. This brachypterousmale appearsto
differ in no otherparticular.
Burr in his original descriptiondoes not mention the
obviouspair of tuberculiformprominenceson thedistalmargin
of the ultimatetergiteabovethe pygidiumin bothsexes.
Themalegenitaliais herefiguredfor thefirsttime,together
with the manubriumof the male and apicalsegmentsof the
abdomenshowingthe forcepsand pygidiumin both sexes.
C. rodensis closelyallied to C. ugandanaBorelli, 1907
(Uganda: Ibanda), also recordedfrom the Cameroonsand
BelgianCongo,but maybedistinguishedby themalegenitalia,
pygidiumandcoloration,especiallyof the.legs,in bothsexes.
Family FORFICULIDAE.
SubfamilyFORFICULINAE.
FORFICULA SJOSTEDTI Burr, 1907.
Forficula sjostedtiBurr, Trans. Ent. Soc., Lond., ,1907: 116.
69. (Kilimanjaro,Kiboscho.)
ForficulabequaertiMenozzi,Rev. Zoo1.Bot. Afr., 119, 1930:96,
figs. 1, 2.69. (Belgian Congo: "Mt. Ninagongaand
Burunga.")
36
Forficula sjostedti var. fusca Borelli, Bull. Mus. Hist. Nat.,
Paris, ,1912:20. O. (Kilimanjaro,Kiboscho.)
Chyulu Hills, 5,200ft. to 6,000ft., April-July, 1938,
800, 6<;1<;1,21 juv. [April 2 nymphs,5,200ft.;
April 10' (immature),1 nymph,5,600ft.; May 10'
macrolabicphase, 5,200ft.; June 30'0', 3<;1<;1,9
nymphs,5,600ft.; June 10, 1<;1,2 nymphs,6,000ft.;
July 20'0, 1<;1,6 nymphs,5,600ft.; July 1<;1,1
nymph,6,000ft.]
Thesespecimensexhibit variousdegreesof shrinkageand
distensionsothataccuratemeasurementsarenot desirable.The
macrolabicmale is, however,in goodconditionand measures
11mm.body,and6.5mm.forceps.Theothermalesapproximate
11mm. body, and 4mm. forceps. The correspondingfigures
for the femalesare 10-11:2.
The presentseriesagreeswell with the materialrecorded
by me(Hincks,1938)fromtheMufumbiroVolcanoesin Belgian
Congo.
The variety fusca of Borelli cited above is not WOrth
distinguishing. '
F. sjostedti is a winglessspeciescharacteristicof certain
volcanicareaswhereit is oftenthe only earwigfoundat alti-
tudesof about2,500m, (approx.8,000ft.) and over. It is a
dominentinsectat thesestationsand Sj6stedtcollectedover
500 specimenson Kilimanjaro from which series Burr first
diagnosedthe species.
Nearly all the recordshithertopublishedare includedin
the followingsummary:-
BELGIAN CONGO AND RUANDA:
MufumbiroVolcanoes,Burr 1912;Rehn 1925,2,900m. to
3,300m. (approx.9,500ft. to 11,000ft.); Menozzi1930;
Hincks 1938,1,900m. to 3,475m. (approx.6,300ft. to
11,500ft. Volcanoes Sabinyo, Karisimbi, Mikeno,
Nyiragonga,Gahinga,and Kinago).
TANGANYIKA:
Xilimanjaro, Burr 1907A,2,000m. to 4,000m. (approx.
6,500ft. to 13,000ft.); Burr 1912;Borelli 1915;Borelli
1912,1915(var. fusca) 1,000m. to 1,700m. (approx.
3,300ft. to 5,600ft.).
Meru, Burr 1907A,4,000m. to 4,300m. (approx.13,200ft.
to 14,200ft.
37
KENYA:
Mt. Kenya, Borelli 1915,1,800m. (approx.6,000ft.) .
AberdareMts., Borelli 1915,3,000m. to 3,100m. (approx.
9,900ft. to 10,200ft.).
Mt. Elgon.
Kikuyu Escarpment.
ElgeyuEscarpment.
Mt. Marakwet,Menozzi1938,2,300m. to 3,500m. (approx.
7,600ft..to 11,600ft.).
MauEscarpment,Borelli 1915(var.fusea),2,420m. (approx.
8,000ft.).
BIBLIOGRAPHY.
Borelli, 1907.Spedizioneal Ruwenzoridi S.A.R. Luigi Amedeo
di Savoia Duca degli Abruzzi., xvii. Nuove speciedi
Forficole.Boll. Mus. Zoo1.Anat. compoTorino,~~,N° 558:
1-6.
Borelli, 1915.Voyagede Ch. Alluaud et R. Jeannelen Afrique
Orientale(1911-12).InsectesOrthopteres,1. Dermaptera.
Paris, 1915:1-20,2 plates.
Burr, 1907A.in Sjostedt,Wissensch.Ergebn.Schwed.Zoolog.
Exped., Kilimandjaro, 17, Orthoptera,1. Dermatoptera.
Uppsala,1907:1-12,1 plate.
Burr, 1907B.UeberDermapterenausDeutsch-Ost-Afrika.Berl.
Entom.Zeitschr.,52, 1907:201-207.
Burr, 1912.UbereinigeneueundinteressanteDermapterenaus.
demKonig1.Zoolog.Museum,Berlin. Sitzungsber.Gesell.
Naturf. Freunde,Berlin, 11912: 311-330.
Hincks, 1939.Explorationdu Pare National Albert. Mission
G.F. de Witte (1933-35),17, Dermaptera.Bruxelles,1938:
1-16.
Menozzi,1938.MissionScientifiquede l'Omo.,4, Zoologie,lase.
34. Paris Museum,1938:135-143.
Rehn, 1925.ZoologicalResultsof the Swedish,Expeditionto
CentralAfrica, 1921. Insecta9. Dermaptera.Arlay for
Zoo!.,17,1925:1-4.
38


Coryndon Memorial museum expedition to the chyulu hills- IX. Dermaptera

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Coryndon Memorial museum expedition to the chyulu hills- IX. Dermaptera

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