Liriomyza garryae Eiseman & Lonsdale 2019, spec. nov.
Creators: name: Eiseman, Charles S.
name: Lonsdale, Owen
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Agromyzidae
Liriomyza
Liriomyza garryae

description: Liriomyza garryae spec. nov.
(Figs. 16, 17, 46, 47, 97–100)
Holotype. TEXAS: Edwards Co., 1.3 mi NW of Camp Wood, 16.iii.2017, em. 24–29.iv.2017, C.S. Eiseman, ex Garrya ovata, #CSE3554, CNC941277 (1³).
Paratypes. ARIZONA: Cochise Co., Cave Creek Canyon, John Hands Campground, 2.iii.2017, em. 30.iii.2017, C.S. Eiseman, ex Garrya wrightii, #CSE3329, CNC940125 (1³); Cave Creek Canyon, Stewart Campground, 2.iii.2017, em. 2–5.iv.2017, C.S. Eiseman, ex Garrya wrightii, #CSE3353, CNC940123, CNC940124 (2♀); Santa Cruz Co., Madera Canyon, 14.iii.2017, em. 17.iv.2017, C.S. Eiseman, ex Garrya wrightii, #CSE3508, CNC940427 (1♀); TEXAS: same data as holotype, #CSE3554, CNC941276, CNC941278 (2♀).
Etymology. The specific epithet refers to the host plant, Garrya Douglas ex Lindl.
Hosts. Garryaceae: Garrya ovata Benth., G. wrightii Torr.
Leaf mine. (Figs. 46, 47) Whitish to brown; varying from broadly linear to trumpet-shaped to a blotch that obliterates the early portion. The dark brown to blackish frass is deposited in scattered grains or more or less continuous arcs. The larva exits through a semicircular slit in the upper epidermis.
Puparium. (Fig. 17) Yellow; formed outside the mine.
Distribution. USA: AZ, TX.
Adult description. Wing length 2.5–2.7 mm (³), 2.6–2.7 mm (♀). Length of ultimate section of vein CuA 1 divided by penultimate section: 2.3–3.5. Eye height divided by gena height: 5.3–5.4. First flagellomere small, rounded, distal margin with slightly longer hairs. Thorax subshining.
Chaetotaxy: Two ors, two ori; males and some females with three ori on one side. Postvertical and ocellar setae subequal to ors. Four strong dorsocentral setae, decreasing in length anteriorly. Acrostichal seta absent. Acrostichal setulae in four rows with posteromedial one or two pairs incurved.
Coloration: (Fig. 16) Setae black. Pigmented areas relatively dark compared to congeners. Back of head, clypeus, posteroventral margin of gena, ocellar tubercle, and posterior margin of frons dark brown with region behind tubercle on vertex paler; posterolateral corner of frons dark brown to base of inner vertical seta, stripe continuing anteriorly along eye margin almost to level of anterior ors; orbital plate lateral to ors with slight brown mottling; yellow regions of head paler below antenna; female sometimes with minute brownish spot at base of setae and setulae on orbital plate, and sometimes with barely visible infuscation around base of arista. Notum dark brown with complete lateral yellow stripe; lateral corner of scutellum dark brown; metanotum dark brown with anatergite and katatergite paler, and posterodorsal corner of anatergite yellow. Pleuron entirely dark brown with dorsal margin of anatergite narrowly yellow. Calypter margin light brown, hairs brown. Male legs dark brown with apex of fore femur yellow with spot as long as wide; apex of mid and hind femora also yellow but with spot shorter; female legs similar but with apical spots on femora all slightly longer than wide. Abdomen mostly dark brownish-black; tergites 1–5 yellow laterally with stripe widest on tergite 2, then 3, with yellow regions visible when viewed dorsally; minute brown spot at base of setae on yellow portions of abdomen.
Genitalia: (Figs. 97–100) Epandrium with one posterodistal spine; inner surface differentiated into long, narrow process that is apically darkened and with minute subapical spine. True surstylus absent; surstylus-like process of epandrium very small, narrow, and with short, rounded apical spine. Phallophorus cylindrical, venter curved. Basiphallus divided between two lateral sclerites that are weakly confluent medially above swollen section of ejaculatory duct; each sclerite extending far past base of mesophallus as separate, laterally sclerotized lobes; right side more irregularly and weakly sclerotized, left side narrower and darker and with additional medial sclerotized band along inner margin. Swollen section of ejaculatory duct with narrowed apex; adjoining basal duct also slightly widened and sclerotized for short distance. Paraphallus absent. Hypophallus broad, lightly sclerotized, slightly pointed apically and widest subbasally; anterior surface densely haired. Mesophallus perpendicular to basiphallus; narrow, dark, cylindrical, almost fully fused to basal stem of distiphallus with only venter incompletely attached; mesophallus+distiphallus with basal stem that is four times longer than wide and slightly widened below apical cup that is twice as wide and split ventrally; margin of cup with dense row of minute spicules that are rounded to pointed; cup enclosing one pair of short tubules. Ejaculatory apodeme not found.
Comments. Liriomyza garryae is a distinctive species with very dark pigment that strongly contrasts the paler regions, the posterolateral corner of the frons is dark to the base of the inner vertical seta with the marking extending anteriorly along the eye margin nearly to the level of the anterior ors, the pleuron is entirely dark excluding a very narrow dorsal line on the anepisternum, the legs are dark with the femora apices yellow, and the abdomen is dark with the lateral margin of the tergites yellow, with this yellow lateral stripe widest and most easily viewed dorsally on tergites 2 and 3.
The abdominal pattern reveals a relationship with grass-feeding species in the Liriomyza flaveola species group, several of which have a dark pattern similar to, but rarely as extensive as that seen in the new species. The key in Lonsdale (2011) will identify L. garryae as one of these species— L. septentrionalis Sehgal. This relationship is supported further by genitalic morphology, including the synapomorphies of the unusual narrow “surstylus” secondarily derived from the epandrium, an expanded and projecting basiphallus, a thicker pigmented subapical section of the duct before the more strongly swollen section typical of all Liriomyza, a dorsally angled mesophallus and a broad cup on the distiphallus. Despite these similarities, many of the other synapomorphies typical of species in this group are not present, suggesting that this dicot-feeder is a possible ancestral lineage that split before diversification on Poaceae occurred: the hypophallus is not fused to the base of the mesophallus; the ejaculatory duct is not apically bent; the mesophallus+distiphallus is not pipe-shaped; the apical section of the distiphallus is not narrowly cup-shaped with one pair of narrower, thicker internal processes; there is no small yellow halo surrounding the base of the vertical setae (absent in some species).
The possible origin of the group outside of a grass-feeding ancestor suggests that other species allied to this group such as the Californian L. abnormis Spencer may not actually feed on Poaceae as previously thought, although Garrya -feeding may represent a secondary return to dicots. This is the first record of any Agromyzidae feeding on the family Garryaceae.
description: Published as part of Eiseman, Charles S. & Lonsdale, Owen, 2019, New State and Host Records for Agromyzidae (Diptera) in the United States, with the Description of Ten New Species, pp. 1-39 in Zootaxa 4661 (1) on pages 12-13, DOI: 10.11646/zootaxa.4661.1.1, http://zenodo.org/record/3378418