Crane Fly Morphology

Morphological terminology follows that of Alexander and Byers (1981).

Crane flies are characterized by their elongate bodies, a pair of narrow wings and long, slender legs.

Gnophomyia tristissima, by Lewis Scharpf Erioptera, by Tom Murray Limoniinae, by Sasha Azevedo
Gnophomyia tristissma,
by Lew Scharpf
Erioptera sp.,
by Tom Murray
Pilaria sp.,
by Sasha Azevedo
     
Tipula furca, by Tom Murray Epiphragma solatrix, by Steve Scott
Tipula furca, by Tom Murray Epiphragma solatrix, by Steve Scott
   
Neocladura delicatula, by Stephen Cresswell Tipula (Yamatotipula) sayi, by Gary Kessler
Neocladula delicatula, by Stephen Cresswell Tipula sayi, by Gary Kessler
   
Nephrotoma ferruginea, by Philip Penketh
Nephrotoma ferruginea, by Philip Penketh

 

Crane flies can be distinguished from all other true flies by the V-shaped transverse suture on the dorsal part of the meso-thorax, and by the absence of ocelli.

Dolichopeza, by Gaga Lin
Dolichopeza sp., by Gaga Lin

 

The body length of crane flies from the front of the head to the tip of the abdomen varies depending upon species. In North America the body sizes vary from 2 mm in Tasiocera ursina, to about 55 mm in Holorusia hespera and 60 mm in the female of Leptotarsus (Longurio) testaceus.

Tasiocera ursina male Holorusia hespera female Leptotarsus testaceus female
Tasiocera ursina, male Holorusia hespera, female Leptotarsus testaceus, female

Head

The head of crane flies is composed of the large compound eyes, the long antennae, and the rostrum which bears the mouthparts.

 

Tipula hirsuta, by Jay Cossey Pedicia albivitta, by Jean-Rene Bibeau
Tipula hirsuta, by Jay Cossey Pedicia albivitta,
by Jean-René Bibeau

 

The compound eyes are large, equal size in both sexes in most species, and usually occupy most of the surface of the head. They are usually glabrous but with short erect hairs in the tribe Pediciini.

The antennae are composed of a cylindrical scape, a subspherical pedicel and 3 (Chionea) to 37 (Gynoplistia) flagellum segments (flagellomeres), commonly 11 in Tipulinae and 12-14 in Limoniinae in the Nearctic Region.

Tipula oleracea, by Frank Koehler  
Tipula oleracea Head, by Frank Koehler  

 

Limonia annulata, by Tom Murray
Limonia annulata Head, by Tom Murray

 

Tipula head by Mark Plonsky Tipula by Gayle and Jeanell Strickland Chionea valga, by Tom Murray Gonomyia, by Ling-Chu Lin
Tipula sp.,
by Mark Plonsky
Tipula sp., by
Gayle and Jeanell Strickland
Chionea valga,
by Tom Murray
Gonomyia sp.,
by Ling-Chu Lin

 

The antennae are generally short to moderate in length, but are often extremely long in male of certain species of Megistocera, Polymera, and Hexatoma.

 

Megistocera fuscana male Hexatoma cinerea male Polymera male
Megistocera fuscana, male Hexatoma cinerea, male Polymera sp., male

 

The flagellomeres are usually simple and unmodified but are branched in species of Ctenophora, Limonia (Idioglochina), and Limonia (Rhipidia).

Ctenophora, by Ling-Chu Lin Limonia (Idioglochina) sp., by Gaga Lin Limonia (Rhipidia) sp., by Gaga Lin
Ctenophora sp.,
by Ling-Chu Lin
Limonia (Idioglochina) sp.,
by Gaga Lin
Limonia (Rhipidia) sp.,
by Gaga Lin

 

The rostrum is conspicuous and often extended into a small projection called nasus in flies of the subfamily Tipulinae. The rostrum is small and inconspicuous in Limoniinae, but greatly elongated in species of Limonia (Geranomyia), Elephantomyia, and Taxorhina. Mouthparts have a pair of four-segmented maxillary palpus. The palpi are short in Limoniinae and longer in Tipulinae.

Nephrotoma alterna female antennae Dicranoptycha elsa antennae, by Gayle and Jeanell Strickland
Nephrotoma alterna,
by Gayle and Jeanell Strickland
Dicranoptycha elsa,
by Gayle and Jeanell Strickland

 

Elephantomyia westwoodi, by Tom Murray Limonia (Geranomyia) sp., by Lew Scharpf Toxorhina species by Brian Womble
Elephantomyia westwoodi,
by Tom Murray
Limonia (Geranomyia) sp.,
by Lew Scharpf
Toxorhina magna,
by Brian Womble

 

Thorax

The thorax is dominated by the sclerites of the mesothorax in both dorsal and lateral aspects, with well-developed V-shaped transverse suture on the mesodorsum. Two spiracles are situated in membranous areas on the pleural region. Halter long to very long in the Nearctic species.

 

Tipula thorax by Mark Plonsky
Tipula dorsimaculata,
by Mark Plonsky

 

ABBREVIATIONS AND TERMINOLOGY OF THE CRANE FLY HEAD AND THORAX
HEAD THORAX Mesonotum: (including prescutum, scutum, scutellum) 
ant: antenna  a bas: anterior basalare  p bas: posterior basalare
flgm: flagellomere anepm: anepimeron  presct: prescutum 
lbl: labella anepst: anepisternum   prn: pronotum 
ped: pedicel  a spr: anterior spiracle   p spr: posterior spiracle 
plp: maxillary palp  cerv scl: cervical sclerite   sct: scutum 
rst: rostrum  cx: coxa   sctl: scutellum 
scp: scape  fem: femur   tib: tibia 
  hlt: halter  tro: trochanter 
  kepm: katepimeron  trn sut: transverse V suture  
  kepst: katepisternum   
  mtn: metanotum   

 

Wings are normally present, but reduced or lost in a few groups, either in both sexes (Chionea) or in females only. Wing venation is highly variable within families, and are important in taxonomy.

 

Tipula wing, by Gayle and Jeanell Strickland
Tipula sp., by Gayle and Jeanell Strickland
 
Dicranoptycha wing, by Strickland
Dicranoptycha sp., by Gayle and Jeanell Strickland
 
Pilaria wing, by Strickland
Pilaria sp., by Gayle and Jeanell Strickland

 

ABBREVIATIONS AND TERMINOLOGY USED TO DESCRIBE THE CRANE FLY WING
A1, A2: branches of anal veins m1, m2, m3: medial cells
C: costa M1, M2, M3: branches of media
CuA: anterior branch of cubitus R: radius
CuA1, CuA2: branches of cubitus R1+2, R3, R4+5: branches of radius
d: discal cell (1st m2 cell) r-m: radial-medial crossvein
M: media Rs: radial sector
m-cu: medial-cubital crossvein Sc: subcosta
m-m: medial crossvein Sc2: branch of subcosta

 

Each leg consists of coxa (plural: coxae), trochanter, femur (pl. femora), tibia (pl. tibiae), and tarsus (pl. tarsi). Tibiae has zero to two terminal spurs. All crane flies have five tarsal segments (tarsomeres), and tarsal claws either simple or variously toothed.

 

Chionea by John Haarstad
Chionea sp., by John Haarstad

Abdomen

Abdomen is long and slender and with nine evident segments. The apex of abdomen in male enlarged into a club-shaped hypopygium, in female extended into elongate, acutely pointed ovipositor. They can be sexed visually in the field by these two characters.

 

Nephrotoma alterna male lateral Nephrotoma alterna male lateral
Nephrotoma alterna male genitalia lateral Nephrotoma alterna female ovipositor lateral
Nephrotoma alterna male,
by Gayle and Jeanell Strickland
Nephrotoma alterna female,
by Gayle and Jeanell Strickland

 

Dicranoptycha elsa female Dicranoptycha elsa male
Dicranoptycha elsa ovipositor Dicranoptycha elsa genitalia
Dicranoptycha elsa female,
by Gayle and Jeanell Strickland
Dicranoptycha elsa male,
by Gayle and Jeanell strickland

 

The genitalia of crane flies as a group are diverse greatly. Various authors have attempted to study these characters and proposed independently for the terminology of the reproductive apparatus. The terminology used here for the male and female genitalia, and for the identification keys follow that of Alexander and Byers (1981).

 

Tipula disjuncta male
Tipula disjuncta male,
by Gayle and Jeanell Strickland
 
Tipula sp. female, by Gayle and Jeanell Strickland
Tipula sp. female,
by Gayle and Jeanell Strickland

 

 

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