Chrysopilus Macquart

Kerr, Peter H., 2010, 2592, Zootaxa 2592, pp. 1-133 : 75-78

Genus Chrysopilus Macquart

Figs. 9–10, 34, 36, 38, 48–49, 65–66, 72, 93–94, 119, 151–152, 160, 175.

Chrysopilus Macquart 1826: 403 . Type species Musca diadema Linnaeus 1767 , by designation of Westwood 1840: 134 (misidentification) = Rhagio aureus Meigen 1804 .

Leptipalpus Rondani 1850: 183 . Type species Tabanus brasiliensis Rondani 1850 , by monotypy.

Heliomyia Doleschall 1857: 402 . Type species Heliomyia ferruginea Doleschall 1857 [= Leptis ferruginosus Wiedemann 1819 ], by monotypy.

Macellopalpus Bigot 1886 : lxviii. Type species Macellopalpus flaveolus Bigot 1886 [= Leptis ferruginosus Wiedemann 1819 ], by monotypy.

† Paleochrysopila Meunier 1892 : lxxxiii. Type species Chrysopilus nagatomii Evenhuis 1994: 292 (= Chrysopilus meunieri Kerr , present work).

Poppiusiella Frey 1918: 30 (as subgenus). Type species Chrysopilus arctica Frey 1918 , by original designation.

Achrysopilus Szilády 1934a: 255 (as subgenus; no type species given; name invalid by article 13.3 of the ICZN code).

Sapporomyia Szilády 1934a: 233 . Type species Leptis basalis Matsumura 1915 , by monotypy.

Chrysopilodes Frey 1954: 15 (as subgenus). Type species Chrysopilus boettcheri Frey 1954 , by monotypy.

Variopilus Frey 1954: 22 (as subgenus). Type species Chrysopilus aequicellulatus Frey 1954 , by original designation.

Solomomyia Nagatomi 1982a: 50 . Type species Solomomyia gressitti Nagatomi 1982a , by original designation. Correct original spelling by present revision. New synonymy.

Solomyia Nagatomi 1982a: 68. Incorrect original spelling.

Poppinsiella Nartshuk 1995: 18. Misspelling. Chrysopyla

Chrysopila , Chrysopyla , errors for Chrysopilus Macquart.

Diagnosis. The monophyly of the species of Chrysopilus is uncertain, due to the recognition of Schizella , which shares all of the potential autapomorphies of the genus. These synapomorphies include thoracic setae that are slightly flattened (scale-like), often with structural color present and a reduced, bare proepimeron. Chrysopilus may also be paraphyletic with respect to Stylospania .

Chrysopilus species are delicate to fairly robust flies, variably sized (3.7 to 19 mm), usually with long, thin legs; black, gray, brown, or orange-brown; often with colored setae on thorax and/or abdomen that adds to color pattern. Wings are hyaline or infuscate, with or without markings; male holoptic (males dichoptic in a few African species), eyes separated in female; first flagellomere subcircular, laterally compressed, with terminal arista; mandibles absent; laterotergite setose; M 3 present; tibial spur formula 0:2:1; hind tibia with short macrochaetae; tergite 9 without ventrolateral arms; female spermathecal ducts with accessory glands. In the northern hemisphere, Chrysopilus species are most commonly confused with species of Rhagio , but may be distinguished by having a single hind tibial spur; arista with microsetae longer than width of arista; and a reduced, bare proepimeron. In the Philippines and possibly its surrounding area, Chrysopilus may be distinguished from Schizella and Stylospania solely by its antenna, which has the arista arising from the first flagellomere centrally (not ventrally), and is the same in both sexes (the female of Stylospania is unknown). In the southern hemisphere, Chrysopilus is distinguished from Atherimorpha by having a single hind tibial spur and aristate antenna.

Description. Head. Clypeus bulbous. Scape approximately same size as pedicel. First flagellomere laterally compressed, rounded and slightly enlarged, bearing fused arista-like extension. Eyes inconspicuously setulose; in female, dichoptic; in male, holoptic or dichoptic, ommatidia evenly distributed, of equal size, or ommatidia split into dorsal and ventral areas and smaller ventrally, not flattened dorsally. Labella with pseudotracheae, longer or shorter than palpus. Theca short and stout, divided into lateral sclerites that are tightly adjacent, apparently fused with suture. Palpus one-segmented. Stipes surrounded by membrane above theca, directed posteriorly (very reduced). Lacinia present, shorter than palpus, tip not serrated. Mandibles absent. Cibarial pump long, clearly not as wide as long. Cornu shorter than cibarial pump. Pharyngeal pump narrow and flat along most of length, approximately half the length of cibarial pump.

Thorax. Mesonotum with or without vittae. Dorsocentral bristles absent; all dorsal setae of equal length. Anepisternum setulose on dorsal margin only or setulose on dorsal and posterior margins. Laterotergite setose, throughout laterotergite. Metallic- or scale-like thoracic setae, often with structural color, present. Proscutellum absent. Subscutellum enlarged or not. Wing hyaline or infuscate, with or without markings; pterostigma present or absent. Lower calypter reduced. Upper calypter variously developed. Costa extends to wing tip or past wing tip. Humeral crossvein well developed. Sc-r crossvein absent or variously developed, positioned distal to h by less than length of h. Dorsal side of R 1 setulose, ventral side bare. All other wing veins bare. R 1 and R 2+3 close together at wing margin. R 2+3 sinuous, apical third ultimately bends slightly anteriorly, toward leading edge of wing margin, length of R 2+3 about as long as R 5, or longer. Base of R 4 –R 5 proximal of, directly above, or distal of distal end of cell dm. R 4 at base usually strongly curved, leading directly to wing margin or with short proximal offshoot at point of curvature near R 5; along most of its length, nearly straight or lightly sinuous. R 4 and R 5 contain wing tip or R 4 ending at wing tip. R 5 longer or shorter than R 4+5 (r-m to R 4 origin). R-m crossvein proximal to one-third of discal cell. Origin of CuA 1 at cell bm. CuA 2 greater than 2/3 length of posterior vein of cell bm. M 3 present. Alula full, rounded, with broad curvature. Anal lobe well developed. Cell cu p closed. Halter knob between 1/3–1/2 length of stem. Tibial spur formula 0:2:1. Hind coxal tubercle absent. Hind tibial macrochaetae present, short. Postmetacoxal bridge reaches internal base of metasternal furcum as incomplete, thin extension.

Abdomen. Abdominal segments evenly tapered. In female, last 3 abdominal segments telescoping; tergite 7 much longer than wide; intersegmental membrane between segments 7 and 8 especially long; sternite 8 as wide as long or wider than long. Male genitalia with epandrium simple, not containing hypandrium ventrally. Epandrium wider than long, strongly notched anteriorly. Tergite 10 present, divided medially, without setae. Hypoproct tomentose, without setae. Cerci directly adjacent to one another, separation distance one quarter width of cercus or less. Cerci, in posterior view flattened or lightly rounded. Hypandrium fused entirely to gonocoxites. Gonocoxite with or without dorsal sinuous ridge, leading to gonocoxal apodeme. Gonocoxal apodemes short or long enough to reach anterior margin of hypandrium. Sperm sac bulbous, without paired swellings ventrally. Lateral ejaculatory processes present, not part of sperm sac posteriorly. Ejaculatory apodeme moderately long to long, reaching at least anterior margin of hypandrium. Ejaculatory apodeme rodshaped or laterally compressed (often upside-down v-shaped in profile). Aedeagal tines absent. Endoaedeagal process absent. Female terminalia with three spermathecae, clubbed or swollen, lightly to moderately sclerotized. Spermathecal ducts no more than three times length of sternite 9, not inflated at base of spermathecae, without swelling halfway between genital chamber and spermathecae. Spermathecal duct accessory glands present or absent; where present, arise at approximately the distal third of the spermathecal ducts or at the base of each spermatheca. Ejection apparatus of spermathecal ducts lightly sclerotized, not thickened, with surface furrows. Common spermathecal duct thickened, moderately long, about as long as longest diameter of genital chamber. Genital chamber elongate, occupying most of sternite 9 area. Accessory gland posterior to genital chamber inconspicuous, easily overlooked even after staining. Sternite 9 anterior end broadly paddle-shaped; posterior end with broad extensions posteriorly, held in vertical plane. Tergite 10 partially split or split into two separate lateral sclerites, short (length less than half width). Sternite 10 split into two sclerites, almost entirely underneath cercal segments. Cercus two-segmented. First segment of cercus not elongate, with or without ventral process. Ventral lobes of first segment of cercus curve ventrally towards one another to form ring, visible in the posterior perspective. Basal cercal segment adjacent dorsally. Second cercal segment not elongated, with or without apical sensory pits.

Larva. Body with 11 segments (not counting head). Thoracic segments with creeping welts ventrally. Head capsule not folded within second segment. Head capsule composed of a single, undivided plate (dorsal plate). Head capsule less than 4.5 times longer than greatest width (1.5 width/ 4.5 length). Mandibular brush present, associated with simple fold of cuticle. Mandibular hook with external groove on adoral surface, smooth, without microsetae. Labral teeth developed, sclerotized, in two rows, converging anteriorly (teeth separated by central depression). Maxilla not sclerotized. Saw sclerite of mandibular base absent. Maxillary palpus soft, segments poorly differentiated; three maxillary palpomeres. Antenna last segment entire (as nub). Antenna three-segmented. Unpaired salivary pump absent. Posterior tentorial expansion free, with thin extension produced dorsally.

Biology. Chrysopilus is cosmopolitan, found on all continents except Antarctica, throughout the tropics, up to near 4000 masl in Bolivia (pers. obs.); as far north as the Arctic circle, and as far south as Chiloé Island, Chile; in Africa, most Chrysopilus species are confined to humid montane forest ( Stuckenberg 1997). Chrysopilus adults may be found throughout the year in tropical habitats, and become more seasonal, relative to their latitudinal displacement from the equator. In temperate climates, they are most common throughout the summer in both the northern and southern hemispheres. Larval Chrysopilus are predators of oligochaetes and soft-bodied insect larvae and may be aquatic, associated with streamside vegetation, or, like Rhagio , may be found in moist soils that are rich in organic matter ( Roberts 1969; Thomas 1978 a, 1978b, 1997; Tsacas 1962). In addition to this, Paramonov (1962) notes that Chrysopilus larvae eat the eggs of Schistocerca and Dociostaurus (Orthoptera) .

The Palaearctic and Oriental regions are the most species-rich areas for Chrysopilus , although there are certainly many more species in the Neotropical Region than are currently recognized .

Literature. Keys to North America, eastern Europe, China, Japan and Africa are provided by Hardy (1949), Narchuk (1969), Yang et al. (1997), Nagatomi (1978) and Stuckenberg (1965, 1997), respectively.

Notes. Lindner (1923) designated the Palaearctic species Chrysopilus obscuripennis Loew as the type species for Bicalcar Lindner. However, Hennig (1955) located the type material of C. obscuripennis and found that there were actually two specimens. One was a typical Chrysopilus , labeled as the type, which evidently Lindner never saw, and the other was a specimen of Atherimorpha , from an unknown source. The latter specimen was the basis of Lindner's description. Thus, Lindner cited Chrysopilus obscuripennis Loew as the type species of Bicalcar , but had described the genus on the basis of a misidentification. Sabrosky (1999) states that the type of Bicalcar is Chrysopilus obscuripennis Loew = " Atherimorpha obscuripennis (Loew) ". This new combination is in error, however, since the specimen that Lindner used for the type species of Bicalcar was not Chrysopilus ; rather, it was an unidentified Atherimorpha species , misidentified as Chrysopilus obscuripennis .

I have seen the type of Chrysopilus arctica Frey and agree with Nagatomi (1982a: 56) and Nartshuk (1995: 18) that this species clearly belongs within Chrysopilus . Stuckenberg (1965) first discusses the confusion regarding C. arctica Frey , but did not have access to relevant material for making a determination at the time. Nartshuk (1995) eloquently describes the confusion regarding this species and justifies the correct placement, although she refers to Poppiusiella as Poppinsiella, in lapsus.

Nagatomi (1982a: 50) comments, in the same passage containing the description of Solomomyia , that “this genus is certainly derived from Chrysopilus .” The recognition of this genus, therefore, by Nagatomi’s own admission, renders Chrysopilus a paraphyletic group. Solomomyia gressitti is distinguished from species of Chrysopilus by having wing vein CuA 1 arising from the discal cell and vein R 4 is also unusually long. Nagatomi mentions another character: “the large area behind ocelli does not make an acute angle with front and is visible in a direct frontal aspect (i.e., when line from antenna to median ocellus is kept horizontal).” This is not an unusual character state for females of any genus within Tabanomorpha . While the features of the wing in Solomomyia appear unique, intrageneric differences of wing venation (and aberrant wing venation) are not uncommon in this area of Diptera . The male genitalia illustrated by Nagatomi (1984: figs. 118–120) are identical to many Chrysopilus species. Since this and all other character states, aside from the aberrant CuA 1 origin (and perhaps the long R 4 vein), are wholly consistent with the genus Chrysopilus , persistence of Solomomyia as a separate genus is unjustified.

The species concept of Chrysopilus rufipes Macquart is uncertain, but placement in Chrysopilus has been established ( Hardy 1920a; Oldroyd in Paramonov 1962), despite its recognition as unplaced by Nagatomi & Evenhuis (1989). Hardy (1920a) wrote that this species was as a junior synonym of C. aequalis (Walker) but Paramonov (1962: 135) preferred to treat these taxa as separate species, citing difficulty in interpreting original types.

Yang et al. (1997: 256) described Spatulina sinensis from a single male specimen from Shaanxi, China and remarked that if the new species is not a true Spatulina , it would belong to a new genus. The authors note that S. sinensis differs from Ptiolina in having mid-upper face deeply sunken and occiput above the neck strongly concave. The head and abdomen are illustrated from the lateral view and the male genitalia are also illustrated; however, none of the putatively special features that they mention are visible. The specimen lacks antennal segments beyond the pedicel and no other potential autapomorphies are given in the text. The male genitalia are quite unlike those found in Ptiolina and it is unclear why the species is placed in Spatulina . Tergite 10 is split medially into two thin, lateral sclerites and the gonostyles are thick, with obvious inward bend, exactly as it is in some species of Chrysopilus . The mid tarsus, hind femur, and all thoracic setae are also missing from the type specimen. All features illustrated and described are fully consistent with those found in species of Chrysopilus , including the deeply sunken face and concave occiput. For this reason, it is more appropriate to place this species in the genus Chrysopilus , as Chrysopilus sinensis (Yang, Yang & Nagatomi) , new combination.

Chrysopilus nagatomii Evenhuis 1994 and Chrysopilus nagatomii Yang & Yang 1991 are primary homonyms. By the principle of priority, C. nagatomii Yang & Yang remains valid and C. nagatomii Evenhuis is a junior homonym. The replacement name Chrysopilus meunieri Kerr , new name, is given here for C. nagatomii Evenhuis , named after the original worker.