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Xylophagidae - US/Canada (in development)

Authors: Zachary Dankowicz

Last updated: July 2022

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Xylophagidae of the United States, Canada

23 species in the following genera:

  • Arthropeas
  • Coenomyia
  • Dialysis
  • Rachicerus
  • Xylophagus

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Genera

Alula margin

Antennae

Eyes

Shape

Cell m3

Arthropeas

strongly convex

7-8 flag.

tapering at tip

not emarginate

relatively robust

open

strongly convex

7-8 flag.

tapering at tip

not emarginate

robust

open

Dialysis

strongly convex

apical arista-like stylus

not emarginate

slender

closed(?)

Rachicerus

nearly straight

20-35 flag.

not tapering at tip

emarginate

slender

closed

Xylophagus (Xylophagus)

nearly straight

8 flag.

not tapering at tip

sca. < 3x ped.

not emarginate

slender

open

Xylophagus (Archimyia)

nearly straight

8 flag.

not tapering at tip

sca. 3x ped.

not emarginate

slender

open

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Arthropeas

Location

Shape

Wings

Scutum

Sides of face

Eastern

somewhat more slender

distinctly banded

grayish pollinose, with three dark stripes

bare

magna

USNM

Mostly Western

somewhat more robust

not banded

almost wholly black

hairy

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Dialysis

Eastern spp

Location

Thorax

Fore tibia

Wing membrane

Tergites

Venation

elongata

(male)

BM

USNM

NoEa. Georgia to S. Quebec

♂: dark to black

♀: orange

pale

mostly hyaline/pale brown

t2+ with broad dark basal bands

four, m3 absent

N. Carolina and Tenn. to New York, west to E. Kansas

reddish

♀: mesopleura dark

mostly dark

light brown

t2-8 reddish with broad dark basal bands

five, m3 closed

N. Florida to Penn. and New Jersey, west to S. Illinois

reddish

mostly dark

mostly hyaline, black-brown veins and medial band

♂: reddish with t1 dark, t2-5 with dark medial elliptical spots, sometimes have light brown basal bands, t6-8 with basal dark bands

♀: reddish with t2-3 with dark medial elliptical spots, occasionally absent on t2

five, m3 closed; veins M2 and M3 don’t always extend to the wing margin

illinoensis

INHS

Illinois

“dark yellow”

“legs dark yellow”

“pale infuscate”

“dark yellow

five, m3 closed

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Dialysis

Western spp

Location

Fore tibial spurs

Thorax

Thoracic setae

Legs

Wing membrane

Tergites

Venation

dispar

(female)

NHMUK

USNM

California to S. British Columbia

♂: 2

♀: 2

♂: dark dark

♀: reddish

♂: reddish, appressed, short

♀: pale, moderately dense, short

♂: reddish with hind coxa, apex of fore and middle tibia, hind tibia and all tarsi dark

♀: reddish, concolor, with apical four segments of tarsi dark

♂: evenly dark

♀: hyaline to pale, dark brown median band

♂: t1-2 dark, t3-7 reddish with dark basal medial bands, caudal margin acute

♀: evenly reddish to dark

five, m3 closed

kesseli

CAS

USNM

N. California

♂: 2

♀: unknown

♂: dark with lateral margin, vitta, and scutellum reddish

♀: unknown

♂: appressed, short

♀: unknown

♂: pale with tibiae and tarsi dark

♀: unknown

♂: pale brown with dark brown medial band

♀: unknown

♂: t1 dark, t2 pale with dark basal triangle, not reaching lateral margin, t3-5 pale with triangles

♀: unknown

five, m3 closed

aldrichi

USNM

California to S. British Columbia E. to Idaho

1

♂: dark to black

♀: reddish to dark

♂: pale, dense, elongate

♀: pale, moderately dense, short

♂: reddish to dark, with coxa and apical tarsal segments dark

♀: reddish, apical half of tibiae and all of tarsi dark

♂: dusky brown with dark brown medial band

♀: hyaline to pale with brown median band

♂: t1 dark, t2 with dark basal triangle, not reaching lateral margin, t3-9 reddish with narrow basal dark bands and medial triangles

♀: t2-6 reddish with broad dark basal bands, t1 and t7-9 dark

five, m3 closed

lauta

type MCZ

type MCZ

San Francisco area

1

♂: dark, glossy; lateral margin reddish

♀: reddish, lateral margin pale; medial, elongate, dark marking anterior to scutellum

♂: reddish, elongate, appressed, very dense

♀: pale, short, moderately dense

♂: reddish with apical half of hind tibia, hind coxa, and tarsi dark

♀: evenly pale

♂: evenly pale brown

♀: hyaline, pale brown median band

♂: t2-4 reddish with dark medial triangle not reaching lateral margin, diminishing to dark spot on t5-8, t1 dark

♀: reddish with t1 dark, t2-6 with dark medial triangle, not reaching lateral margin

♂: five, m3 open or closed

♀: five, m3 closed

mentata

type INHS

types USNM

California to Washington

1

♂: dark, sometimes glossy

♀: pale

♂: short, appressed, moderately dense

♀: pale, very short, appressed

♂: pale to reddish with tarsi dark, occasionally hind basitarsus paler; on some specimens dorsal half of hind femur dark

♀: reddish with apex of tibia and all tarsal segments dark

♂: amber to pale brown, dark brown median band

♀: amber to light brown, brown median band

♂: reddish with t1 dark, t2 with dark medial basal triangle, not reaching lateral margin, t3-8 generally with medial dark spot, occasionally absent on t3-5

♀: reddish, t2-6 with dark medial spot, occasionally absent on t3-6

five, m3 closed

reparta

type AMNH

type AMNH

S. California

1

♂: reddish; pleura dark

♀: reddish to dark

♂: short, appressed

♀: pale, short, appressed

♂: reddish with apical third of tibiae and all of tarsi dark, hind coxal tubercle sometimes reduced

♀: reddish, tarsi dark, hind coxa without tubercle

♂: evenly amber

♀: pale to amber, brown median band

♂: reddish with t1 dark, t2-8 with medial dark triangles or spots not reaching lateral margin

♀: reddish with t1 dark, t2-6 with dark medial spot not reaching lateral margin

five, m3 closed

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Rachicerus

Location

Flagellomeres

Thorax

Vittae

Katepisternum

Legs

fulvicollis

BM (Georgia)

USNM

Eastern

♂: 27-34, moniliform

♀: 18-19, moniliform

pale, glossy

indistinct

pale

Eastern

♂: 21, moniliform

♀: 20-22, moniliform

black, subshiny to glossy (as well as the abdomen, unlike others)

indistinct

♂: pale, apex of tarsomere 1 and all of tarsomeres 2-5 dark brown

♀: pale

Eastern

♂: 24-27, pectinate, reddish towards base

♀: 23-26, pectinate, reddish towards base

pale to dark

dark brown to dark

♂: pale, with hind coxa, apex of hind femora and tibiae, and tarsomeres 4 and 5 dark

♀: dark with tibia and tarsomeres 1-2 of fore leg, tibia and tarsomeres 1-3 of middle leg, basal half of tibia, tarsomeres 1-2 and basal half of tarsomere 3 of hind leg pale

Western

♂: 17-21, av. 19, moniliform

♀: 14-16, av. 15, moniliform

dark

orange

♂: pale with dorsal half dark

♀: yellow

♂: pale, tarsi 2-5 dark

♀: pale to pale brown

niger

CU (California)

California, Oregon

♂: 17-21, moniliform

♀: 14, moniliform

paleish to dark brown, glossy

♂: dark brown

♀: absent

dark

dark, glossy

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Xylophagus (Xylophagus)

Location

Frons

Hind coxal tubercle

Tergites

Mesothorax

Legs

nitidus

USNM

New Hamp. to W. Ontario

evenly pruinose

with

dark, glossy

note from 2022 says orange??

dark, glossy

foreleg pale to reddish, tarsomeres 4-5, dark; middle leg pale to reddish, apical half of femur pale dark; hind leg with coxa, trochanter and basal half of femur reddish, remaining segments and base of coxa dark

gracilis

N. California to W. Alaska

evenly pruinose

without

♂: dark to black, lightly pruinose along medial line and on apical segments

♀: brown to dark

♂: black, lightly pruinose

♀: dark brown to dark, pruinose

♂: fore, middle, and hind legs evenly dark

♀: coxae and trochanters pale, pruinose; femora, tibiae, and tarsomeres 1-3 reddish; apical two tarsomeres dark; hind coxa with basal margin dark

New Bruns. to Georgia, west to Missouri and W. Ontario

pruinose with glossy band dorsal to antennae

without

♂: dark to black, glossy

♀: dark, lightly pruinose

black with vittae narrow

♂: fore leg pale, apex of tarsomere 2 and all of tarsomeres 3-5 dark; middle leg pale with basal edge of coxa, dorsal margin of femur, apex of tibia and basitarsus, and all of tarsomeres 2-5 dark; hind leg pale, base of coxa, apical third and dorsal margin of femur, apex of tibia and basitarsus and all of tarsomeres 2-5 dark

♀: fore leg with coxa and trochanter reddish, remaining segments and base of coxa dark, basal third of basitarsus pale; middle and hind legs dark with basal third of basitarsus pale

cinctus

(male)

LUOMUS

USNM

California to Alaska, east to Nova Scotia and south to Miss.

pruinose with glossy band dorsal to antennae

without

♂: dark to black, sometimes t2-5 with orange markings

♀: dark to black with t2-4 and median oval area of t5 yellowish-orange; occasionally abdominal tergites may be evenly black

black

♂: fore leg with coxa and trochanter pale, coxa pruinose; femur, tibia, and tarsi reddish with anterior margin of tibia and tarsomeres 1-3 and all of tarsomeres 4-5 dark; middle leg reddish with coxa pruinose, anterior margin of tibia and tarsomeres 1-3, and all of tarsomeres 4-5 dark; hind leg reddish, basal margin of coxa, apex of femur, base and apex of tibia, apex of tarsomeres 1-3, and all of tarsomeres 4-5 dark

♀: fore leg with coxa and trochanter pale, coxa pruinose; femur, tibia and tarsi reddish with tarsomeres 4-5 dark; hind leg reddish with basal margin of coxa and tarsomeres 4-5 dark

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Xylophagus (Archimyia)

Location

Frons

Legs

Alaska to Colorado, east to New Bruns.

evenly glossy

♂: fore and middle legs pale to reddish, tarsomeres 2-5 pale dark; hind leg reddish, base of coxa, dorsal margin of tibia, and tarsomeres 2-5 dark

♀: fore and middle legs reddish with tarsomeres 4-5 dark; hind leg reddish with base of coxa, dorsal margin of tibia, apex of tarsomeres 1-2, and all of tarsomeres 3-5 dark

Maryland to New Bruns., west to the plains of Alberta

pruinose, with glossy band dorsal to antennae

♂: fore leg pale to lightly reddish, tarsomeres 4-5 dark; middle leg pale to reddish, tarsomeres 4-5 and apex of tarsomere 3 dark; hind leg pale to reddish with base of coxa, dorsal margin of tibia, apex of tarsomere 1, and tarsomeres 2-5 dark

♀: legs dark to black, tibial spurs reddish

S. California to the Yukon Terr.

pruinose, with glossy band dorsal to antennae

♂: fore leg reddish with coxa pale, tarsomeres 4-5 dark; middle leg reddish; hind leg reddish, coxa with basal dark band, tarsomeres 4-5 dark, occasionally dorsal margin of tibia dark

♀: fore leg with coxa and trochanter pale, femur, tibia and tarsomeres 1-3 reddish, tarsomeres 4-5 dark to black; middle leg reddish with tarsomeres 3-5 dark; hind leg reddish with basal margin of coxa and tarsomeres 3-5 dark

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References

Sources for this entire project include:

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References

Leonard, M. D. 1930. A revision of the dipterous family Rhagionidae (Leptidae) in the United States and Canada. Mem. Am. ent. Soc. 7: l-181. https://books.google.com/books?id=mMMyAQAAMAAJ&pg=RA3-PA1&lpg=RA3-PA1

McAlpine, 1981. Manual of Nearctic Diptera Volume 1. Agriculture and Agri-Food Canada Research Branch, pp. 489-492.

Webb, 1978. A Revision of the Nearctic Genus Dialysis (Diptera: Rhagionidae). Journal of the Kansas Entomological Society, Vol. 51, No. 3 (Jul., 1978), pp. 405- 431.

Webb, 1979. A Revision of the Nearctic Species of Xylophagus (Diptera: Xylophagidae). Journal of the Kansas Entomological Society, Vol. 52, No. 3 (Jul., 1979), pp. 489-523.

Webb, 1983. A New Genus and Species of Nearctic Coenomyiid (Diptera: Coenomyiidae). Proceedings of the Entomological Society of Washington, Vol. 85, No. 4, pp. 822-825.

Webb, 1984. A Revision of the Nearctic Species of Rachicerus (Diptera: Rachiceridae). Journal of the Kansas Entomological Society, Vol. 57, No. 2 (Apr., 1984), pp. 298-315.

Woodley, 1993. Napemyia Webb, a new synonym of Dialysis Walker (Diptera: Xylophagidae). Proceedings of the Entomological Society of Washington 95: 635-838.

Woodley, 2011. A World Catalog of the Xylophagidae (Insecta: Diptera). Myia 12: 455-500.