Calycomyza artemisivora Eiseman & Lonsdale 2018, spec. nov.
Creators: name: Eiseman, Charles S.
name: Lonsdale, Owen
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Agromyzidae
Calycomyza
Calycomyza artemisivora

description: Calycomyza artemisivora spec. nov.
(Figs. 12, 14, 102, 257–261)
Holotype: OKLAHOMA: Payne Co., Mehan, 36.014339° N, 96.996744° W, 10.v.2016, em. 31.v.2016, M.W. Palmer, ex Artemisia ludoviciana, #CSE2526, CNC653998 (1♂).
Paratype: OKLAHOMA: same collection as holotype, CNC 653997 (1♂).
Etymology. The specific epithet refers to the host plant, Artemisia L.
Host. Asteraceae: Artemisia ludoviciana Nutt.
Leaf mine. (Fig. 102) A pale, greenish-white blotch on the upper leaf surface; frass in diffuse brown patches, mostly not reaching the margins of the mine.
Puparium. (Fig. 14) Yellowish-brown to reddish-brown; formed outside the mine.
Distribution. USA: OK.
Adult description. Wing length 2.6mm (♂). Female unknown. Length of ultimate section of vein CuA1 divided by penultimate section: 2.5. Eye height divided by gena height: 8.0. First flagellomere rounded. Arista pubescent. Notum subshining.
Chaetotaxy: Two ori, two ors; slightly decreasing in length anteriorly. Ocellar and postvertical setae subequal to ors. Three dorsocentral setae, posterior two strong, anterior seta more closely set to second seta and approximately 3/5 its length. Acrostichal setae in six rows, inset from dorsocentral rows. Mid tibia with two posterolateral setae.
Coloration: (Fig. 12) Setae dark brown. Head mostly light yellow; antenna, back of head, clypeus, palpus, margin of vertex, small rounded triangular spot surrounding tubercle and posterolateral corner of frons to base of inner vertical seta dark brown to black; posterolateral spot on frons extending as line on orbital plate, fading to yellow at base of posterior ors. Thorax black with complete lateral yellow stripe on scutum and postpronotum, and anepisternum with light yellow dorsal stripe that is very narrow anteriorly and ¼ height of sclerite posteriorly. Calypter margin pale, hairs dark brown. Haltere white. Legs black with apex of fore femur narrowly light yellow and base of fore tibia yellowish. Abdomen dark brown to black.
Genitalia: (Figs. 257–261) External genitalia of Calycomyza type, with surstylus somewhat flattened anteroposteriorly, with tubercle-like setae largely directed posteriorly. Phallophorus with short ventral surface. Basiphallus composed of two narrow triangular plates fused to base of hypophallus distally. Hypophallus large, Ushaped, very weakly sclerotized, broad and flat, especially laterally. Paraphallus as long as mesophallus, subrectangular with membranous margin, weakly sclerotized along most of length but base thick and dark; base fused to basoventral plate of mesophallus. Mesophallus dark, tubular, ends slightly narrower, width less than than half length; base with broad ventrobasal plate with narrow stem; space between mesophallus and distiphallus with minute, dark, ovate sclerite. Distiphallus nearly ¾ length of mesophallus, asymmetrical with twist to right side, tapered apex, with very short, slightly narrower basal stem, ventral surface split between thick shallow crests that partially expose strongly haired medial surface. Ejaculatory apodeme with stout stem and shorter, paler blade; sperm pump broad, membranous, with one pair of small lateral sclerotizations; duct annulated, basally pigmented.
Comments. The related species Calycomyza artemisivora and C. eupatoriphaga will key to the similar Calycomyza artemisiae (Kaltenbach) using Spencer & Steyskal (1986). The new species differ minimally in color of the anepisternum and fore femur, but C. artemisivora is distinct genitalically in the broader, paler hypophallus (Figs. 260, 261), the narrower paraphallus, the straighter, longer mesophallus (rounder and more medially constricted in C. eupatoriphaga; Figs 271, 272), and the shorter distiphallus that is tapered at the base and apex (larger and somewhat peanut-shaped in C. eupatoriphaga).
Calycomyza artemisiae, as defined by previous authors, is conceptually broad and likely consists of at least several distinct species that have been treated as interspecific variation or subspecies. This historical treatment is understandable, as these species have conserved external features and a dark, asymmetrical distiphallus that resists characterization. While external features are likely unreliable for differentiating these species, male genitalic features differ in relatively distinct ways that elsewhere in the family would be used as strong support for separate specific status. In the present case, both new species of the C. artemisiae group described here— C. artemisivora and C. eupatoriphaga (genitalia in Figures 268–272) —differ from each other and other members of the group in morphology of the hypophallus, mesophallus, paraphallus and distiphallus, as well as in the relative dimensions of the mesophallus and distiphallus. This contradicts Spencer’s (1990) statement that “this species-complex, with its remarkably wide distribution… it must remain a matter of subjective judgement whether individual populations are considered to represent mere variation, or are given subspecific status or are treated as full species”, but we do ultimately agree with him that this group may be relatively difficult to untangle, and that “[a] detailed revision of the complex, with the study of even more material, could prove of great interest.”
While the identities of other specimens historically treated as Calycomyza artemisiae still require verification, the genitalia of the specimens examined here do not resemble those of any of the dissected Palearctic or Colombian males in the literature, nor of the western Nearctic C. artemisiae marcida Spencer. The Ontario male of C. artemisiae illustrated in Spencer (1969), which Spencer originally noted had a phallus different from other males of that species he had examined, has been verified as belonging to C. eupatoriphaga, described as new below.
description: Published as part of Eiseman, Charles S. & Lonsdale, Owen, 2018, New state and host records for Agromyzidae (Diptera) in the United States, with the description of thirty new species, pp. 1-156 in Zootaxa 4479 (1) on pages 27-28, DOI: 10.11646/zootaxa.4479.1.1, http://zenodo.org/record/1452913