Liriomyza euphorbivora Eiseman & LonsdaleLiriomyza

Eiseman, Charles S., Lonsdale, Owen, Linden, John Van Der, Feldman, Tracy S. & Palmer, Michael W., 2021, Thirteen new species of Agromyzidae (Diptera) from the United States, with new host and distribution records for 32 additional species, Zootaxa 4931 (1), pp. 1-68: 27-29

publication ID

https://doi.org/10.11646/zootaxa.4931.1.1

publication LSID

lsid:zoobank.org:pub:88CF2B0D-E02B-46E1-9F52-1B95F717FC8F

DOI

http://doi.org/10.5281/zenodo.4678608

persistent identifier

http://treatment.plazi.org/id/0395A00B-7038-EB57-2A99-FF4B661866B7

treatment provided by

Plazi

scientific name

Liriomyza euphorbivora Eiseman & Lonsdale Liriomyza
status

spec. nov.

Liriomyza euphorbivora Eiseman & Lonsdale   , spec. nov.

( Figs. 40–43 View FIGURES 40–47 , 75 View FIGURES 73–86 , 140–143 View FIGURES 140–143 )

Holotype. USA. OKLAHOMA: Payne Co., Marena , 36.072618°, -97.247242°, 29.v.2018, em. 14.vi.2018, M.W. Palmer, ex Euphorbia marginata   , # CSE4617, CNC1144138 View Materials (1♁).  

Etymology. The specific epithet refers to the host plant genus, Euphorbia L.  

Host. Euphorbiaceae   : Euphorbia marginata Pursh.  

Leaf mine. ( Fig. 75 View FIGURES 73–86 ) The single collected mine was a whitish (partially greenish), roughly circular blotch on the upper leaf surface, centered on the midrib, 7 mm across when complete, with frass in a few small, dark grains and lumps. A photo taken of the lower leaf surface at the time of collection shows what appears to be a 0.2-mm wide, epidermal linear mine, but this does not appear to be contiguous with the mine that contained the fly larva and we believe it is unrelated. It is not discernible in the preserved leaf.

Puparium. Yellow; formed outside the mine.

Phenology and voltinism. The only known specimen was collected as a larva in late May, emerging as an adult in mid-June.

Distribution. USA: OK.

Adult description. Wing length 1.5 mm (♁). Female unknown. Length of ultimate section of vein M 4 divided by penultimate section: 2.8. Eye height divided by gena height: 3.0. First flagellomere small, rounded. Thorax subshining.

Chaetotaxy: Two ori, two ors; subequal to ocellar and postvertical setae. Four dorsocentral setae, only first seta long, with second seta ⅖ length. Five rows of acrostichal setulae.

Coloration: ( Figs. 40–43 View FIGURES 40–47 ) Setae dark brownish-black. Head yellow with ocellar spot dark brown; posterolateral corner of frons dark brown nearly to base of outer vertical, paler brown to base of inner vertical; back of head and clypeus brown. Scutum dark brown with wide, complete lateral yellow stripe on scutum (reaching base of posterior supra-alar and intra-alar) that continues along posterior margin as narrow line along scutellum. Mediotergite dark brown; anatergite brown with posterodorsal corner yellow; katatergite yellow with posteroventral corner brown. Pleuron yellow in base color; anepisternum with wide clavate anteroventral stripe (wider anteriorly) and narrow posteromedial line along suture; anepimeron mottled brown; katepisternum brown below level of seta; meron mostly brown. Scutellum dark anterolaterally. Legs yellow with basal half of fore coxa dark brown, mid coxa basally brownish and hind coxa mottled brown; base of femora narrowly brown (reduced ventrally); tibiae brown with base of fore and mid tibiae yellow, fore tibia yellower and hind tibia darker; tarsi brown. Abdomen brown dorsally, stripe narrowing posteriorly to tergite 5; epandrium brown. Calypter margin yellow with grey tint, hairs greyish-brown.

Genitalia: ( Figs. 140–143 View FIGURES 140–143 ) Epandrium not fused to surstylus, with one spine. Surstylus with two apical spines. Phallophorus with venter much reduced, short. Basiphallus sclerotized along dorsal and left lateral surface with extension on left distal margin below paraphallus. Paraphallus simple, narrow. Hypophallus with small rod-shaped sclerite with apical hairs. Ejaculatory duct swollen and pigmented apically. Mesophallus slightly shorter than distiphallus, subcylindrical, fused to distiphallus dorsally, with slight ventral carina along suture. Distiphallus slightly wider than mesophallus, distal half shallow and cup-shaped, enclosing one pair of short processes, angled dorsally; basal half slightly narrower, sides parallel in ventral view, tapering basally in lateral view. Ejaculatory apodeme large and well-developed with broad blade; sperm pump with broad sclerotized cup-like venter.

Comments. This is the second Liriomyza   to be reared from Euphorbia   in North America, after L. euphorbiella Eiseman & Lonsdale. That   species is likewise known only from Payne Co., Oklahoma, but it was reared from E. heterophylla var. cyathophora (Murray) Griseb.   rather than E. marginata   , and its mine begins with a distinct linear portion and does not cross the midrib. Mines on E. marginata   similar to that of L. euphorbivora   have been photographed in Ontario ( Mews 2019b), and the aborted mine on E. cf. brachycera Engelm.   in Colorado noted by Eiseman & Lonsdale (2019) could conceivably have represented this species. TSF has found largely linear Liriomyza   mines on E. curtisii Engelm.   in North Carolina, but so far adults have not been reared from these.

Worldwide, 12 Liriomyza   species have now been reported from Euphorbia   , including three listed by Benavent- Corai et al. (2005) that were omitted without explanation from the review of Euphorbia   -feeding Agromyzidae   by Martinez & Sobhian (2000). Of these three, L. congesta (Becker)   normally feeds on Fabaceae   , and L. sonchi Hendel   on Asteraceae   , so these records seem likely to be erroneous (both are derived from a paper on parasitoids of Agromyzidae   in Valencia, published in 1987). The record of the highly polyphagous L. sativae Blanchard   appears plausible, however, apart from its being poorly documented (the cited source, Martinez (1993), is apparently a simple list of host genera, and is a publication we have been unable to obtain after multiple attempts; Martinez & Sobhian (2000) explicitly stated that L. sativae   is “not yet recorded on Euphorbia   ”). Possibly this record refers to McClanahan (1975), who caged a population of L. sativae   with E. pulcherrima Willd. ex Klotzsch   and observed light mining but no puparium formation. Whether the unidentified Nearctic mines noted above represent any of these 12 species remains to be seen, but to aid in the identification of Liriomyza   specimens reared from Euphorbia   , a modified version of the key by Martinez & Sobhian (2000) is presented below with L. euphorbiella   , L. euphorbivora   , and L. sativae   added, and supplemented with data from Ellis (2020).

Updated key to the species of Liriomyza   feeding on Euphorbia

1. Mesonotum with yellow longitudinal bands................................................................ 2

1′. Mesonotum largely black, without distinct yellow longitudinal bands............................................ 3

2. Back of head, at level of vertical bristles, entirely yellow. Acrostichal setulae less numerous (5 to 8), irregularly arranged in two rows...................................................................... Liriomyza euphorbiae Martinez   [mine initially narrow and serpentine, developing into an irregular blotch; on E. kotschyana Fenzl   and E. macroclada Boiss.   ; Turkey]

2′. Back of head, at level of vertical bristles, partly brown. Acrostichal setulae more numerous, arranged in four almost regular rows...................................................................... Liriomyza heringi Nowakowski   [mine a blotch; on E. esula   L., E. nicaeensis All.   , E. palustris   L., E. salicifolia Host   , and possibly E. amygdaloides   L.; Lithuania, Romania, former Soviet Union]

3. Wings without vein dm-cu.............................................................................. 4

3′. Wings with vein dm-cu................................................................................. 5

4. Orbits between upper ors and vti completely yellow. Abdominal tergites without yellow lateral band. Penultimate section of M4 2.5 to 3 times longer than last section.............................................. Liriomyza balcanica (Strobl)   [mine broadly linear or a linear-blotch; on E. cyparissias   L., E. esula   , E. myrsinites   L., and possibly E. amygdaloides   ; Germany and Poland to Turkey]

4′. Upper part of orbits black. At least the basal part of abdominal tergite with yellow border. Penultimate section of M4 maximum 2 times longer than last section................................................... Liriomyza myrsinitae Hering   [mine a blotch preceded by a short linear portion; on E. myrsinites   ; Bulgaria, Spain]

5. Orbits between upper ors and vti completely yellow. Mesophallus long, narrow, fused to distiphallus with broad, bilobed cuplike base from which one pair of short weakly scleritized tubules emerge.................. Liriomyza pascuum (Meigen)   [mine a primary blotch, generally containing several larvae; on E. amygdaloides   , E. characias   L., E. dulcis   L., E. esula   , E. glareosa Pall. ex M.Bieb.   , E. palustris   , and E. pithyusa   L.; throughout Europe]

5′. Upper part of orbits black. Phallus not as above............................................................. 6

6. Frons yellow at base of inner vertical seta. Distiphallus entirely split, short, with minute basal stem contrasting rounded apical chamber...................................................................... Liriomyza strigata (Meigen)   [branching mine centered on the midrib; a polyphagous species, uncommonly reported from unspecified Euphorbia   ; throughout Europe]

6′. Frons brown at base of inner vertical seta. If distiphallus entirely split and short ( L. huidobrensis   ), then apical chamber narrow, not much wider than stem............................................................................... 7

7. Surstylus with two apical spines. Distiphallus angled dorsally, with very short apical chamber........................ 8

7′. Surstylus with one apical spine. Distiphallus various, but not as above........................................... 9

8. Eye 4.8–5.9 times higher than gena. Posterior margin of scutum along scutellum black. Ventral 2/3 of anepisternum brown. Femora entirely yellow. Left distal margin of basiphallus long, extending to apex of paraphallus. Basal stem-like half of distiphallus (fused to mesophallus) gradually narrowing to point of fusion with mesophallus............................................................................................ Liriomyza euphorbiella Eiseman & Lonsdale   [mine initially narrow and linear with the frass in alternating strips, expanding to an elongate blotch with irregular and more or less diffuse frass; on E. heterophylla var. cyathophora   ; USA]

8′. Eye 3.0 times higher than gena. Posterior margin of scutum narrowly yellow. Anepisternum yellow with brown clavate spot. Femora brown basally (paler on venter). Left distal margin of basiphallus shorter, not reaching apex of paraphallus. Basal stemlike half of distiphallus parallel-sided and abruptly wider than mesophallus.. Liriomyza euphorbivora Eiseman & Lonsdale   [mine a roughly circular blotch on upper leaf surface, centered on the midrib, with frass in a few small, dark grains and lumps; on E. marginata   ; USA]

9. Femora usually only brown basally, but sometimes more heavily mottled. Abdominal tergites narrowly yellow laterally. Acrostichal setulae (acr) between second and fourth pairs of dorsocentral setae in four more or less regular rows. Distiphallus simple, cup-shaped................................................................... Liriomyza sativae Blanchard   [mine linear; a polyphagous species, with one questionable record from unspecified Euphorbia   (light mining of E. pulcherrima   observed in a laboratory setting, but no puparia were formed); North and South America; introduced in Europe, Asia, Africa, Australia, and several Pacific islands]

9′. Femora brown basally and with additional light to heavy dorsal mottling. Lateral margin of abdominal tergites brown. Acros- tichal setulae (acr) between second and fourth pairs of dorsocentral setae in two to three more or less regular rows. Distiphallus divided into one pair of short tubules......................................... Liriomyza huidobrensis (Blanchard)   [mine linear, often following the midrib and lateral veins; a polyphagous species, uncommonly reported from unspecified Euphorbia   according to Martinez & Sobhian (2000); the only record listed by Weintraub et al. (2017) is one of E. marginata   from China; this South American fly is introduced in North America, Europe, Asia, and Africa]

Characters of the thorax of Liriomyza euphorbivora   best differentiate it from other Liriomyza   externally, as four rows of acrostichal setulae and a very narrow yellow posterior margin on the scutellum is not found in many species. In the United States, it occurs in L. eupatoriella Spencer   , but this species has both vertical setae on yellow, the femora are entirely yellow (not basally brown) and the distiphallus is of a different structure, being more cup-shaped with the base strongly narrowed in lateral view. In Canada, the new species keys most readily to L. cracentis Lonsdale   and L. agrios Lonsdale   , although the spot on the anepisternum of these two species is much larger, their femora are entirely yellow, and the distiphallus is more cup-shaped, without a short apical chamber. The phallus instead shows more similarity to species without the posteriorly yellow scutum. These include L. conclavis Lonsdale   (host unknown), L. asclepiadis Spencer   and L. peleensis Spencer   (both on Asclepias   ), which have a medially constricted mesophallus and a very sharply upturned distiphallus, and L. subasclepiadis Spencer   (also on Asclepias   ), which also has a more strongly angled distiphallus.

Updated key to the species of Liriomyza   feeding on Euphorbia

1. Mesonotum with yellow longitudinal bands................................................................ 2

1′. Mesonotum largely black, without distinct yellow longitudinal bands............................................ 3

2. Back of head, at level of vertical bristles, entirely yellow. Acrostichal setulae less numerous (5 to 8), irregularly arranged in two rows...................................................................... Liriomyza euphorbiae Martinez   [mine initially narrow and serpentine, developing into an irregular blotch; on E. kotschyana Fenzl   and E. macroclada Boiss.   ; Turkey]

2′. Back of head, at level of vertical bristles, partly brown. Acrostichal setulae more numerous, arranged in four almost regular rows...................................................................... Liriomyza heringi Nowakowski   [mine a blotch; on E. esula   L., E. nicaeensis All.   , E. palustris   L., E. salicifolia Host   , and possibly E. amygdaloides   L.; Lithuania, Romania, former Soviet Union]

3. Wings without vein dm-cu.............................................................................. 4

3′. Wings with vein dm-cu................................................................................. 5

4. Orbits between upper ors and vti completely yellow. Abdominal tergites without yellow lateral band. Penultimate section of M4 2.5 to 3 times longer than last section.............................................. Liriomyza balcanica (Strobl)   [mine broadly linear or a linear-blotch; on E. cyparissias   L., E. esula   , E. myrsinites   L., and possibly E. amygdaloides   ; Germany and Poland to Turkey]

4′. Upper part of orbits black. At least the basal part of abdominal tergite with yellow border. Penultimate section of M4 maximum 2 times longer than last section................................................... Liriomyza myrsinitae Hering   [mine a blotch preceded by a short linear portion; on E. myrsinites   ; Bulgaria, Spain]

5. Orbits between upper ors and vti completely yellow. Mesophallus long, narrow, fused to distiphallus with broad, bilobed cuplike base from which one pair of short weakly scleritized tubules emerge.................. Liriomyza pascuum (Meigen)   [mine a primary blotch, generally containing several larvae; on E. amygdaloides   , E. characias   L., E. dulcis   L., E. esula   , E. glareosa Pall. ex M.Bieb.   , E. palustris   , and E. pithyusa   L.; throughout Europe]

5′. Upper part of orbits black. Phallus not as above............................................................. 6

6. Frons yellow at base of inner vertical seta. Distiphallus entirely split, short, with minute basal stem contrasting rounded apical chamber...................................................................... Liriomyza strigata (Meigen)   [branching mine centered on the midrib; a polyphagous species, uncommonly reported from unspecified Euphorbia   ; throughout Europe]

6′. Frons brown at base of inner vertical seta. If distiphallus entirely split and short ( L. huidobrensis   ), then apical chamber narrow, not much wider than stem............................................................................... 7

7. Surstylus with two apical spines. Distiphallus angled dorsally, with very short apical chamber........................ 8

7′. Surstylus with one apical spine. Distiphallus various, but not as above........................................... 9

8. Eye 4.8–5.9 times higher than gena. Posterior margin of scutum along scutellum black. Ventral 2/3 of anepisternum brown. Femora entirely yellow. Left distal margin of basiphallus long, extending to apex of paraphallus. Basal stem-like half of distiphallus (fused to mesophallus) gradually narrowing to point of fusion with mesophallus............................................................................................ Liriomyza euphorbiella Eiseman & Lonsdale   [mine initially narrow and linear with the frass in alternating strips, expanding to an elongate blotch with irregular and more or less diffuse frass; on E. heterophylla var. cyathophora   ; USA]

8′. Eye 3.0 times higher than gena. Posterior margin of scutum narrowly yellow. Anepisternum yellow with brown clavate spot. Femora brown basally (paler on venter). Left distal margin of basiphallus shorter, not reaching apex of paraphallus. Basal stemlike half of distiphallus parallel-sided and abruptly wider than mesophallus.. Liriomyza euphorbivora Eiseman & Lonsdale   [mine a roughly circular blotch on upper leaf surface, centered on the midrib, with frass in a few small, dark grains and lumps; on E. marginata   ; USA]

9. Femora usually only brown basally, but sometimes more heavily mottled. Abdominal tergites narrowly yellow laterally. Acrostichal setulae (acr) between second and fourth pairs of dorsocentral setae in four more or less regular rows. Distiphallus simple, cup-shaped................................................................... Liriomyza sativae Blanchard   [mine linear; a polyphagous species, with one questionable record from unspecified Euphorbia   (light mining of E. pulcherrima   observed in a laboratory setting, but no puparia were formed); North and South America; introduced in Europe, Asia, Africa, Australia, and several Pacific islands]

9′. Femora brown basally and with additional light to heavy dorsal mottling. Lateral margin of abdominal tergites brown. Acros- tichal setulae (acr) between second and fourth pairs of dorsocentral setae in two to three more or less regular rows. Distiphallus divided into one pair of short tubules......................................... Liriomyza huidobrensis (Blanchard)   [mine linear, often following the midrib and lateral veins; a polyphagous species, uncommonly reported from unspecified Euphorbia   according to Martinez & Sobhian (2000); the only record listed by Weintraub et al. (2017) is one of E. marginata   from China; this South American fly is introduced in North America, Europe, Asia, and Africa]

Characters of the thorax of Liriomyza euphorbivora   best differentiate it from other Liriomyza   externally, as four rows of acrostichal setulae and a very narrow yellow posterior margin on the scutellum is not found in many species. In the United States, it occurs in L. eupatoriella Spencer   , but this species has both vertical setae on yellow, the femora are entirely yellow (not basally brown) and the distiphallus is of a different structure, being more cup-shaped with the base strongly narrowed in lateral view. In Canada, the new species keys most readily to L. cracentis Lonsdale   and L. agrios Lonsdale   , although the spot on the anepisternum of these two species is much larger, their femora are entirely yellow, and the distiphallus is more cup-shaped, without a short apical chamber. The phallus instead shows more similarity to species without the posteriorly yellow scutum. These include L. conclavis Lonsdale   (host unknown), L. asclepiadis Spencer   and L. peleensis Spencer   (both on Asclepias   ), which have a medially constricted mesophallus and a very sharply upturned distiphallus, and L. subasclepiadis Spencer   (also on Asclepias   ), which also has a more strongly angled distiphallus.

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Diptera

Family

Agromyzidae

Genus

Liriomyza

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Diptera

Family

Agromyzidae