Taxonomy of Nearctic Lycorina
By David Wahl
Cushman (1920) was the first treatment of the Nearctic lycorinine fauna. The tribe Lycorinini was erected by Cushman & Rohwer (1920) for Lycorina Holmgren and Toxophoroides Cresson;
it was placed within the Pimplinae s.l., with "affinities" to the Glyptini and Phytodietini. Cushman described a new genus, Chlorolycorina,
and provided three keys to the genera and Nearctic species. As Cushman's characters are pertinent for the analysis of the Nearctic fauna,
the keys are reproduced below as one key with updated morphological terminology. It should NOT be used for present-day identification.
1. Propodeum sharply areolated, distinctly separated from metapleura. Scutellum quadrate, truncate at apex. Vein 2-Cu of hind wing complete. Black with only clypeus and minute markings on head and scutellum yellow.
............................................. Lycorina Holmgren
-- Propodeum with at most an obsolete carina and traces of median carinae, not separated from metapleura. Scutellum trapezoidal, rounded apically. Vein 2-Cu of hind wing absent or basally incomplete. Body highly ornamented.
............................................. 2
2. Posterior face of propodeum perpendicular; apical carina obsolete. Body black with yellow markings and mesosoma more or less reddish. Wings hyaline.
............................................. 3 (Chlorolycorina Cushman)
-- Posterior face of propodeum oblique; apical carina absent; dorsal and posterior faces of propodeum separated by difference of sculpture. Body mostly yellow with blackish markings, at least without red. Fore wing usually apically infuscate.
............................................. 5 (Toxophoroides Cresson)
3. Hind tibia with alternating bands of white and black; tarsus white at base. Mesoscutum more or less red. Triangular areas of tergites each with white spot.
............................................. scitula (Cresson)
-- Hind tibia white, reddish in middle; tarsus black. Mesoscutum without red. Triangular area of tergites immaculate.
............................................. 4
4. Hind coxa red. Ovipositor distinctly longer than hind tibia.
............................................. albomarginata (Cresson)
-- Hind coxa black with white apex. Ovipositor and hind tibia equal in length.
............................................. soror Cushman
5. Apex of fore wing not apically infuscate.
............................................. xanthozonata (Ashmead)
-- Apex of fore wing apically infuscate.
............................................. 6
6. Head in dorsal view almost evenly ovate, genae convex, eyes not bulging. Head in frontal profile with eyes not higher than vertex.
............................................. apicalis (Cresson)
-- Head in dorsal view not evenly ovate, genae flattened, eyes bulging. Head in frontal profile with eyes higher than vertex.
............................................. glaucomatus Cushman
It should be noted that:
- Cushman expressed doubt concerning the status of xanthozonata: "It is very likely the male
of [apicalis], but since the infuscation of the apices of the
wings is very weak, and since it comes from such a widely different locality, it seems inadvisable to
synonymize it."
- The inclusion of apicalis, although Mexican in distribution, was due to Cushman's belief
that it was "closely allied to
xanthozonata (Ashmead) and possibly identical with it . . ." (Cushman, 1920: 12).
- The number of specimens that Cushman had on hand is surprising to the modern sensibility: the
female holotype, two
females, and one male for albomarginata; one female for apicalis; two females for glaucomatus;
the female holotype and two females for scitula; one female for soror; the male holotype for
xanthozonata.
Townes (1944: 79-80) synonymized Chlorolycorina with Toxophoroides but otherwise followed Cushman's species concepts:
- Toxophoroides albomarginatus (Cresson)
- Toxophoroides glaucomatus Cushman
- Toxophoroides scitulus (Cresson)
- Toxophoroides soror (Cushman)
- Toxophoroides xanthozonatus (Ashmead)
Townes later (Townes & Townes, 1951) placed soror as a subspecies of albomarginatus.
Walkley (1967) synonymized xanthozonatus with apicalis.
Carlson (1979) restored xanthozonatus to specific status, resulting in the following classification:
- Toxophoroides albomarginatus albomarginatus (Cresson)
- Toxophoroides albomarginatus soror (Cushman)
- Toxophoroides glaucomatus Cushman
- Toxophoroides scitulus (Cresson)
- Toxophoroides xanthozonatus (Ashmead)
All post-Cushman authors placed the Nearctic species in Toxophoroides, presumably
(but not explicitly) recognizing the extra-limital nature
of the related genera Lycorina Holmgren (Palearctic and Oriental regions) and
Gonioglyphus Seyrig, 1932 (Ethiopian region). Although
Townes (Townes, Momoi, & Townes, 1965) included all three genera in Lycorina, he later
(Townes, 1970) reverted to the previous classification of three genera.
The genera were delimited on the basis of the degree of propodeal carination and the
development of vein 2/Cu in the hind wing. Gauld (1984) found a continuous
range of variation in the propodeal carinae, and therefore placed all species in one genus, Lycorina.
Gauld's study of the Costa Rican lycorinine species (Gauld, 1997) is relevant to the Nearctic fauna.
All Nearctic taxa belong to his apicalis species-group,
defined by the presence of a median longitudinal carina connecting the anterior and posterior margins
of the pronotum. Also of note is his redescription and
discussion of apicalis Cresson. He considers it to be "a widespread tropical American species whose known
range extends from southern Mexico southwards into Brazil".
With this as background, the AEI collection was examined with the aim of producing an updated key to
Nearctic Lycorina.
It should be noted that whilst Gauld and I both agree on the value of ovipositor length as a diagnostic
character, we measure
it differently: Gauld compares the lengths of the ovipositor sheath and hind tibia, whilst I use the
estimated length of the ovipositor
compared to the hind tibia. While the ovipositor base can be hidden due to positioning of the metasomal
apex, many specimens have the
sheaths curled and distorted, thereby making accurate measurement impossible. I believe it is more
accurate to use the ovipositor length,
measured from the base to the apex
In the event that the ovipositor base is obscured by the apical metasomal segments, one can usually estimate its position
Lycorina albomarginata Cresson
Glypta albomarginata Cresson, 1870: 157. Type: female (Academy of Natural Sciences of Philadelphia). Not examined.
Chlorolyocorina soro Cushman, 1920: 10. Type: female (National Museum of Natural History). Not examined.
Cushman erected soror for a single specimen from New Mexico. Later authors recognized soror to be
closely allied with albomarginata and treated it as a subspecies of the latter, presumably
maintaining it as a formal entity on the basis of Cushman's definition of soror having of
a black hind coxa with a white apex, and a shorter ovipositor than is found in albomarginata s.s.
As mentioned above, Cushman had four specimens of albomarginata and one specimen of soror
before him in 1920. More complete geographic sampling shows that hind coxal color is not reliable.
Northern specimens of albomarginatus (such as from Michigan to New York) range from
1) a completely brownish-red coxa, to
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2) a brownish-red coxa with an apicodorsal dark spot to
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3) a completely black coxa with a narrowly white apex
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While specimens from the southwestern USA often have a black coxa with a white apex,
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about 40% of the females have various mixtures of brownish-red and fuscous on the coxa
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(about 15% of the males show this color mix).
Body coloration is generally darker in the northern part of the range: the mesoscutum can
have the yellow markings reduced to only small spots at the bases of the
notauli.
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The apical tergal white bands can be
considerably narrowed as well.
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Specimens from
Nebraska show considerable white, yellow, and brownish-red on the mesosoma; the hind coxa
varies from completely brownish-red to brownish-red with an apicodorsal dark spot.
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Florida specimens show
even less black on the mesosoma; coxal coloration is as for Nebraska. While specimens from the
southwestern USA (Cushman's soror) have the black hind coxa described above, there is much more
white and brownish-red coloration on the mesosoma than in northern individuals with black hind
coxa; the white tergal bands are much more prominent.
Interestingly, Cushman's ovipositor character holds up: southwestern USA specimens have
the ovipositor 1.1-1.3x as long as the hind tibia, while eastern USA specimens have a range
of 1.4-1.5x as long as the ovipositor. In addition, southwestern specimens have a gentle but
distinct curve to the ovipositor; the ovipositors of eastern specimens are straight. Can the
combination of the color of southwestern specimens (black or partially black hind coxae that
are not the result of general melanism) with the shorter curved ovipositor be used to diagnose
soror? Unfortunately, there are exceptions that belie the use of this character. A specimen from
the San Jacinto Mountains of California has pure black hind coxae but the ovipositor is straight
and 1.5x as long as the hind tibia. Two specimens from southeastern Oregon (Malheur Co.: Juntura)
have brownish-red hind coxae with a brown apicodorsal spot, and straight ovipositors that range
from 1.2-1.3x as long as the hind tibia.
In summary, albomarginata consists of a confusing mix of populations, representing
either a very polymorphic species or a cluster of similar species that can be separated only
with molecular data. Recognition of soror is not justifiable at this time.
Lycorina apicalis Cresson
Lycorina? apicalis Cresson, 1874: 407. Type: female (Academy of Natural Sciences of
Philadelphia). Not examined.
Although Gauld (1997) did not consider apicalis to range north of southern Mexico, it is not out of
the question that the species could be discovered in the southwestern USA. It is therefore included
in the new key to Nearctic Lycorina to guard against confusion with the similar glaucomata.
Cushman differentiated apicalis and glaucomata on the basis of eye and gena characters (see above).
He apparently had on hand only one specimen of apicalis (Mexico: no other locality information given)
that had been compared to the holotype (Mexico: Cordoba) by S.A. Rohwer; Rohwer considered the two
specimens to be conspecific. I examined 15 specimens from Costa Rica that were excellent matches with
Gauld's redescription of the species, particularly in regard to body size and the punctation of T1.
When these are compared to specimens of glaucomata, Cushman's head characters cannot be observed.
Walkley's synonymization of xanthozonata with apicalis (Walkley, 1967) is not
supported (see the discussion under glaucomata).
The habitus of a representative specimen is given
Lycorina glaucomata Cushman
Toxophoroides glaucomatus Cushman, 1920: 12. Type: female (National Museum of Natural History).
Not examined.
Glypta xanthozonata Ashmead, 1890: 449. Type: male (National Museum of Natural History).
Examined.
While glaucomata is readily distinguished from other Nearctic Lycorina (see the key), its
relationship to luzae Gauld is not so clear. Comparison of glaucomata with a luzae
paratype in the AEI collection reveals
the two species to be more or less identical in color pattern
The only discernable differences are chromatic:
1) a brown stripe on the anterior surface of the
hind femur in luzae
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vs. a unmarked femur in typical pale
glaucomata (not the northern dark populations; see below),
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2) a yellowish-white ground color in luzae vs. a
rich yellow ground color in glaucomata,
and 3) T4-5 yellowish-white with black markings
in luzae
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vs. the presence
of faint reddish-brown highlights in glaucomata [11_Lycorina glaucomata_#0053-02].
I cannot say if this is only geographical color variation or indicative of specific differences.
L. glaucomata has a latitudinal color range with northern specimens showing more extensive
black coloration than southern ones; this readily seen in this comparison between specimens from
Ontario
Northern specimens can have the mesoscutal yellow reduced so that only two thin lateral
longitudinal stripes are present (thus approximating the pattern in scitula); note that the
stripes are yellow in glaucomata but white in scitula.
Glypta xanthozonata was described by Ashmead (1890) on the basis of a single male
from Missouri and was transferred to Toxophoroides by Viereck (1911). Cushman maintained
it as a valid species, although he thought it "extremely like apicalis": "It is very likely
the male of that species, but since the infuscation of the apices of the wings is very weak and since
it comes from such a widely different locality, it seems inadvisable to synonymize it." Later workers
recognized the species as well, with Carlson (1979) recording the species from southeastern North
Carolina, southern Florida, and Missouri. Examination of the holotype reveals it to be an unusually
pale specimen of glaucomata
The wing apices are barely infuscated,
and the body coloration is whitish-yellow and
dark brown instead of deep yellow and black of glaucomata. It is clearly not apicalis,
due to the presence of a dark mark above the propodeal insertion and the coarsely and closely
punctate central dark part of T1.
Lycorina scitula (Cresson)
Glypta scitula Cresson, 1870: 155. Type: female (Academy of Natural Sciences of Philadelphia).
Not examined.
This species is easily distinguishable from other Nearctic species by the characters in the key.
While some individuals exhibit more dark mesosomal coloration
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than others,
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this does not appear to be geographically correlated. Florida specimens have great reduced dark markings
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Distributions (based upon specimens in the American Entomological Institute and the Canadian National
Collection of Insects):
L. albomarginata. CANADA: MB, NB, NS, QC, SK ; MEXICO: Jalisco, Zacatecas; USA: AZ,
CA, CO, FL, KS, KY, MI, NM, NY, OH, OR, TX. Apparently transcontinental, south to south-central
Mexico.
L. glaucomata. CANADA: ON; USA: FL, KS, KY, MD, MI, MO, OK, NC, NJ, OH, SC, TN, TX.
Eastern Nearctic.
L. scitula. CANADA: NB; USA: GA, KS, KY, MD, MI, MO, NC, NY, OH, SC, VA, WV.
Eastern Nearctic.
LITERATURE CITED
Ashmead, W.H. 1890. Description of new Ichneumonidae in the collection of the U.S. National Museum. Proceedings of the United States National Museum, 12: 387-451
Carlson, R.W. 1979. Family Ichneumonidae. In: Krombein, K.V., P.D. Hurd, D.R. Smith, and B.D. Burks (eds.). Catalog of Hymenoptera of America North of Mexico. Vol. 1. Smithsonian Institution Press: Washington, D.C. 1198 pp.
Cresson, E.T. 1870. Descriptions of new species belonging to the subfamily Pimplariae found in America north of Mexico. Transactions of the American Entomological Society, 3: 143-172.
Canadian Entomologist 4: 61-64.
Cushman, R.A. 1920. The North American ichneumon-flies of the tribes Lycorini, Polysphinctini, and Theronini. Proceedings of the United States National Museum, 58: 7-48.
Cushman, R.A. & S.A. Rohwer. 1920. Holarctic tribes of the ichneumon-flies of the subfamily Ichneumoninae (Pimplinae). Proceedings of the United States National Museum, 57: 379-396.
Gauld, I.D. 1984. An Introduction to the Ichneumonidae of Australia. 413 pp. British Museum (Natural History), London.
Gauld, I.D. 1997. The Ichneumonidae of Costa Rica, 2. Memoirs of the American Entomological Institute, 57: 1-485.
Townes, H. 1944. A catalogue and reclassification of the Nearctic Ichneumonidae. Part I. Memoirs of the American Entomological Society, 11: 1-477.
Townes, H. 1970. The genera of Ichneumonidae, part 3. Memoirs of the American Entomological Institute, 13: 1-307.
Townes, H., S. Momoi & M. Townes. 1965. A catalogue and reclassification of the Eastern Palearctic Ichneumonidae. Memoirs of the American Entomological Institute, 5: 1-661.
Townes H, & M. Townes. 1951. Ichneumonidae. In: Hymenoptera of America north of Mexico - synoptic catalog. (Muesebeck, C.F. W, Krombein, K.V., & Townes, H., eds.) United States Department of Agriculture, Agricultural Monograph 2, 184-409.
Viereck, H.L. 1911. Descriptions of six new genera and thirty-one new species of Ichneumon flies. Proceedings of the United States National Museum 40: 173-196.
Walkley, L.M. 1967. Family Ichneumonidae. In: Krombein, K.V., & B.D. Burks (eds.). Hymenoptera of America north of Mexico – synoptic catalog. United States Department of Agriculture, Agricultural Monograph 2, supplement 2: 60-213.
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