THE NYMPHS OF OPHIOGOMPHUS

540 PROCEEDINGS OF THE NATIONAL MUSEUM

11. THE NYMPHS OF OPHIOGOMPHUS

The

following generic characterizationofthe OpJiiogonvplms

nymph

isgiven

by Needham

The Dragon

FliesofIllinois:*

Nymph^stout,little flattened. Head abruptly sloping forward from theocelli.

Labrimipilot-shaped. Antennae withthetwobasalsegmentsglobular,tliirdsegment twiceaslong asbothbasal,muchflattenedandlaidclosebeside thelabrum. Fourth jointaminute rudiment. Medianlobeofmentumrounded, withborderofshort blunt teethandadoubleseries offringingscales. Lateral lobesnearlystraight,not terminatinginanend hook and minutelydenticvdated within;movable hookshort, arcuate.

Legsrathershort. ForeandmiddletibiaeAvithexternal hooks, wing-cases divari- cate, strongly sloping downward toward the sides. Dorsal hooks on abdominal segments on 2 or 3-9. Tenth segment notinclosed by the 9th but triquetral, exceeding thelateralspines,itsown^lateralmargin forminga partofthemarginof theabdomen.-

The nymphs

ofthewesternspecies of thisgenusareseparatedfrom oneanotherwith considerable difficulty. Figures224, 227, 230, 233 and236

show

labia ofthefivespecies,which,aswithanyothersingle characterofthenymphs, varytoolittletobeofanyuseinseparating the species.

The

dorsal spines are also practically the

same

in aU species.

The

characters usedin the following notesaretheonly ones I have found to be of value.

KEYTONYMPH.S.

a}.Segments6-9withlateralspines.

6'.Superiorappendagesthree-fourthslengthofmedianappendage; dorsal hooks

strong hison.

¥. Superiorappendagestwo-thirdslengthofmedianappendage; dorsalhooks heavy butlow, onlythoseon segments2-4 erect occidentisando.californicus.

a?. Segments7-9withlateralspines.

c^ Dorsal spinesweakandlow,onlythefirsttwoorthree erect severus.

c^. Dorsal spines slender,erect,well developed morrisoniand m.nevadensis.

iBull.111.StateLab. Nat.Hist., vol._6,art.1,1901,p. 57.

=ThenymphsofErpetogomphusaredistinguishedbydorsalspineson^segments2-4 only. Ihaveexam- inednymphsofcompositus,designatus,andanundescribedspecies.

2192.

DRAG0NFLIE8, CALIFORNIA AND NEVADA— KENNEDY. 545

Figs.219-22S.—OpmoGOMPHUsnymphs. 219.().moreisoni. 220. O. severus. 221.O.morrisoni NEVADENSISI 222.O. BISON. 223.O. OCCmENTIS.

65008°—Proc.N.M.vol.52

—

17 35

546

PROCEEDINGS OF THE NATIONAL MUSEUM.

vol. 52.

Figs. 224-226.—Ophiogomphusbison,nymph. 224.Mentum. 225.Teethand setae onMmDLElobe ofmentum. 226.segments6-10.

Figs. 227-229.—Ophiogomphusmoreisoni.

Figs. 230-232.—Ophiogomphusseveeus.

Figs.233-235.—Ophiogomphus moeeisoninevadensis.

F>GS. 236-238.—Ophiogomphusoccidentis.

NO. 2192.

DRAG0NFLIE8, CALIFORNIA AND NEVADA—KENNEDY. ₅₄₇

OPHIOGOMPHUSBISONSelye,nymph.

A

dark, heavily mottled

nymph,

veryhairy, inwhich characterit

resemblesmornsoni;27-33labial teeth,thoseat eitherendoftherow- being onlyhalf aslongasthemedian^teeth.

Abdomen

withthedorsal hooks on segments2-9 longer thaninthe otherspecies^{^}andheavier;

lateral hooks on segments 6-9.

The

paired superiorappendages three-fourthsthelengthofthemedianappendage. (Seefigs.222,224- 226, and 239.)

Length, 28-29

mm.;

abdomen, 17.5; hind femur, 4,5; width of abdomen,8.5-9.

The

abovedescriptionisfromexuviaecollectedonthe

San

Lorenzo River nearSantaCruz, whichis the typelocalityfor theimago of the species. I have not taken this emerging, butno other species

was

collected on this stream and these exuviae agreewith exuviae IhavecollectedatChico,wherehison

was

onthe wing. Needham's description of

nymphs

and exuviae collected

by

Schwarz on

Lake Tahoe

^fits

my

exuviaeof lison,butIfound mornsoni on

Lake Tahoe

andonlymornsoniin the

Tahoe

region. Ibelievethelocalitygiven

isa mistake. Mornsoniis.aspecies ofthe coolupperlimit of

gom-

phine life occurring at from 4,000 to 10,000 feet elevation, while

all

my

recordsforhison arefrom thelow hotvalleys of central Cali- fornia.

OPHIOGOMPHUSOCCIDENTISHagen, nymph.

A medium

colored

nymph;

alengthwise row ofsmall fight spots along either side of the

dorsum

ofthe abdomen. Only moderately hirsute,

hairy than the nevadensis exuvia from

Winnemucca

Slough,butlessso thanseverus; 21-25labial teethwhich are equal inlength thi'oughout the row.

Abdomen

withdorsalhooks onseg- ments 2-9, these noticeably variable in height and strength,but usually with thefii'st hook slender, erect, the remaindershort and heavy. Lateral hooks on segments 6-9.

The

paired superior ap- pendagestwo-thirds the lengthof themedian appendage. (Seefigs.

223,236-238, and240.)

Length, 28

mm.;

abdomen, 18; hind femur, 4.5; width of a1)-

domen, 8-8.5.

The

abovedescriptionis fromexuviae collectedon theColumbia RiveratUmatiUa,Oregon. I

am

sureofthe identityofthis,though

Itooknoneactuallyemerging.

OPHIOGOMPHUSOCCIDENTIS CALIFORNICUSKennedy, nymph.

I have eight occidentis exuviae from the American River at Sacramento,Cahfornia. These are probably of the yellow variety, californicus,butI cansee no characters separating

them

from the occidentis

nymphs

of theColumbia River. In these thelateralab-

iNotlongerthanin morrisoniandmontanus, butinthese theyare slender.

548 PROCEEDINGS OF THE NATIONAL MUSEUM.

VOL. 52.

dominalspines arevery variablein length,

some

being shortandblimt, othersunusuallylong. Suchvariations occurevenontheindividual.

Inonethespineson segment6 are blunt,on segments7-9 long and pointed.

OPHIOGOMPHUSSEVERUSHagen, nymph.

A medium

colored

nymph,

only moderately hairy; 26-29 labial teeth.

Abdomen

withdorsalhooks on segments2-9,low and weak.

244

I'lGS.239-243.—OPHIOGOMPHUS,DORS.^L 8riNESOFNVMrilS. 239.U. BISON. 240.O. OCCIDENTIS. 241 O.MOERISONI. 242.O.MORRISON!NEVADENSIS. 243.O.SEVERUS.

Figs.244-246.—Ophiogomphus, lateral fringeonsegment7of nymph. 244.O. morrisonineva- DENSIS. 245.O. SEVERUS. 246.O. MORRISONI.

Lateral hooks on segments 7-9.

The

paired superior appendages four-fifths aslongasthemedian appendage. (Seefigs.220,230-232, 243and245.)

Length, 28

mm.;

abdomen, 19; hind femur, 4.75; width of abdomen, 8.

DescribedfromexuviaecollectedonSatus Creek,

Yakima

Comity, Washington. Ihavespecimensof thistaken emerging.

OPHIOGOMPHUSMOKRISONISelys.nymph.

A medium

to dark

nymph,

very hairy; each abdominal segment on its dorsal aspect fringed posteriorly with nimierous long hairs;

25-29labial teeth.

Abdomen

with dorsalhooks on segments2-9, these longer

and more

erect and

slender than inotherspecies,

NO.2192.

DRAGONFLIES, CALIFORNIA AND NEVADA— KENNEDY. 549

exceptn'evadensis,which they resemble,but notdiffering enoughto

make

apositive specific character. Lateralhooks on segments ^7-!).

The

paired superior appendages four-fifths as long as the median appendage. (Seefigs.219,227-229, 241 and246.)

Length, 28

mm.

^; abdomen,18; hindfemur,₅;widthofabdomen,8.

Describedfromnumerous emerging

nymphs

andexuviaecollected on

Donner

Lake, July23, 1914.

OPHIOGOMPHUSMORRISONI NEVADENSISKennedy,nymph.

A

large fightcolored

nymph,

nakedexceptforafewshorthairson thetibiaeand aboutthehead; 26labial teeth.

Abdomen

withdorsal hookson segments2-9, longer,

slender,and

erectthanin otherspeciesexcept

mormom.

Lateralhookson segments7-9.

The

paired superior appendages four-fifths as long as the median appendage. (Seefigs.221,233-235,242and244.)

Length, 31

mm.;

abdomen, 20; hind femur, 5.5; width of abdomen, 8.5.

Described from a single male exuvia collected on

Winnemucca

Slough at

Pyramid

Lake, August, 1914.

The

only other

gomphine

fomid at this place,whichis a branch outlet oftheTruckee River, was Erpetogomphuscompositus. Thisisnot the

nymph

ofthat.*

OPHIOGOMPHUS,species.

In the Cornell collection are five dried

nymphs

from

"N.

Mex."

Theseareverycloseto severus,butdifferinhavingthedorsalspines noticeablyweaker,and only the spine on segment2 erect,those on segments 3-9pointingcaudad.

Severus is recorded

by

Selys^{^}from theMerinoValley (elevation, 9,600feet).

New

Mexico. Ihaveseenno specimensofimagoesfrom

New

Mexico. Selys records theMerino Valley as on theColorado.

Ifso, this

may

be the

nymph

of arizonicus.

12.

THE WESTERN

SPECIES

OF GOMPHUS, INCLUDING A NEW

SPE-

Dalam dokumen Proceedings of the United States National Museum (Halaman 62-67)

540 PROCEEDINGS OF THE NATIONAL MUSEUM

11. THE NYMPHS OF OPHIOGOMPHUS

The

nymph

by Needham

The Dragon

The nymphs

show

The

same

The

DRAG0NFLIE8, CALIFORNIA AND NEVADA— KENNEDY. 545

—

PROCEEDINGS OF THE NATIONAL MUSEUM.

DRAG0NFLIE8, CALIFORNIA AND NEVADA—KENNEDY. 547

A

nymph,

Abdomen

The

mm.;

The

San

was

was

nymphs

by

Lake Tahoe

my

Lake Tahoe

Tahoe

gom-

my

A medium

nymph;

dorsum

more

Winnemucca

Abdomen

The

mm.;

The

am

them

nymphs

548 PROCEEDINGS OF THE NATIONAL MUSEUM.

some

A medium

nymph,

Abdomen

244

The

mm.;

Yakima

A medium

nymph,

Abdomen

and more

more

DRAGONFLIES, CALIFORNIA AND NEVADA— KENNEDY. 549

make

The

mm.

nymphs

Donner

A

nymph,

Abdomen

more

more

mormom.

The

mm.;

Winnemucca

Pyramid

The

gomphine

nymph

nymphs

"N.

DRAG0NFLIE8, CALIFORNIA AND NEVADA—KENNEDY. ₅₄₇