Pelignellus freidbergi, Zatwarnicki & Mathis, 2019

Zatwarnicki, Tadeusz & Mathis, Wayne N., 2019, New discoveries in New World Atissini as revealed in revision of Pelignellus Sturtevant & Wheeler (Diptera: Ephydridae), Israel Journal of Entomology (Oxford, England) 49 (2), pp. 11-26 : 17-22

Pelignellus freidbergi n. sp.

( Figs 2–10)

Pelignellus subnudus sensu Wirth 1968 : 77.6 [misidentification; Neotropical catalog].

LSID: urn:lsid:zoobank.org:act:C7D5204C-E92E-4F6A-B85E-7055081842E1 .

Etymology: The species is named to honor Amnon Freidberg.Amnon accompanied us to Costa Rica where we conducted field work.Although he focused on tephritoid Diptera , he collected several other flies, including numerous specimens of shore flies. Amnon is exceptional in the field and is a “born” naturalist. His skills and success as a collector are legendary. It is our pleasure to name this species after him.

Diagnosis: Small shore flies, body length 1.10–1.65 mm. Body mostly gray with central portion of scutum brown.

Head ( Figs 2, 7, 8): Frons dark gray, varying slightly depending on angle of view; mesofrons forming isosceles triangle, greater distance across vertex, uniformly colored; 2 pairs of small interfrontal setae, posterior seta inserted at level with anterior ocellus or slightly posterior, anterior seta inserted about midway between anterior ocellus and anterior margin of frons; 4 short fronto-orbital setulae, anterior 3 proclinate and aligned along lateral margin of frons, posterior setula larger than anterior 3, lateroclinate to lateroreclinate, inserted medially from alignment of anterior 3; pseudopostocellar and ocellar setae reduced, similar in size to anterior fronto-orbital setulae. Antenna mostly gray to dark gray, only ventral portion of basal flagellomere yellow to yellowish orange; basal half of arista swollen, bearing 5 dorsal rays, these relatively short, none greater in length than height of basal flagellomere, apical half of arista style-like. Face in lateral view concave, with silvery microtomentum, epistomal margin robustly produced. Facial and genal setae and setulae silvery while. Eye elliptical, obliquely oriented. Gena relatively high; gena-to-eye ratio 0.58–0.64.

Thorax ( Figs 7–9): Scutum with much of midportion brown, anterior and lateral areas gray; scutellar disc with small, medial area tan; 1 pair of presutural acrostichal setae and only posterior dorsocentral seta better developed; other acrostichal and dorsocentral setulae short; notopleuron with 1–2 faint, short setulae anterodorsad of anterior seta. Pleural area generally gray, pleural setae reduced, pale colored. Wing ( Fig. 9) faintly tan, somewhat hyaline; wing ratio 0.42–0.44; costal vein ratio 0.68–0.71; M vein ratio 0.58–0.63. Legs generally gray to blackish gray; only basal 3 tarsomeres yellowish.

Abdomen: Tergites uniformly gray, similar to pleural areas. Male terminalia ( Figs 3–6): Epandrium in posterior view ( Fig. 3) as an inverted U, in lateral view ( Fig. 4) with ventral portion projected anteriorly as a triangle; cercus in posterior view ( Fig. 3) broadly ovate, in lateral view ( Fig. 4) narrowly semihemispherical; surstylus elongate, narrow, in posterior view ( Fig. 5) irregularly curved, bearing setulae medially at midlength and apically, in lateral view ( Fig. 6) elongate, narrow, straight, slightly tapered; postgonite in lateral view ( Fig. 6) narrow, elongate, mostly parallel sided but with narrow, relatively short, acutely pointed projection sub-basally and at midlength, in ventral view ( Fig. 5) elongate, narrow, medial surface irregularly sinuous; pregonite in lateral view ( Fig. 6) tiny, more or less triangular, bearing 2 apical setulae, in ventral view ( Fig. 5) oriented obliquely medially; fused aedeagus/ phallapodeme in lateral view ( Fig. 6) elongate, apical half digitiform, basal half more robust and with U-shaped notch sub-basally, in ventral view ( Fig. 5) narrow, moderately elongate, apical third tapered to acutely pointed apex; hypandrium in lateral view ( Fig. 6) very slender, elongate, shallowly sinuous. Female terminalia ( Fig. 10): Female ventral receptacle ( Fig. 10): Operculum as inverted U or thimble, as high as wide, dorsal curvature moderately narrow, ventral margin flat, extended process J-shaped, with narrow, upturned feet at apex.

Holotype: ♂ “ COSTA RICA. Guana [caste]: Playa Puerto Soley (11°02.5'N 85°40.1'W), 16 June 2003, D. & W. N. Mathis / ENT 00198835 [plastic bar code label] / HOLOTYPE ♂ Pelignellus freidbergi

Zatwarnicki & Mathis USNM [red].” The holotype is double mounted (minuten in block of plastic elastomer), is in excellent condition, and is deposited in USNM.

Paratypes: 33♂ 4♀ bear the same label data as the holotype ( USNM) ; Costa Rica: 17♂ 8♀ Guanacaste: Playa de Cuajiniquil (10°56.1'N 85°42.2'W), beach, 16.vi.2003, D. & W.N. Mathis ( USNM) ; 6♂ 7♀ Puntarenas: Bahia Gigante ( Rio Lajas ; 9°53.8'N 84°56'W), beach, 22.vi.2001, D. & W.N. Mathis ( SMNHTAU, USNM) ; 1♀ Malpaís (09°37.6'N 85°09.1'W), beach, 21.vi.2001, D. & W.N. Mathis ( USNM) .

Other material examined: El Salvador: 1♂ Sonsonate: Acajutla [13°35.7'N 89°49.6'W], 29.xii.1964, M.E. Irwin ( USNM) . Panama: 1♀ Cocle: Playa Santa Clara (08°22.4'N 80°06.4'W), 2.vii.1967, W.W. Wirth ( USNM) ; 6♂ 48♀ Darien: Jaqué (07°31'N 78°09.6'W), 24–28.vii.1952, W.W. Wirth ( USNM) ; Panama: 1♂ 1♀ Fort Kobbe (08°55.1'N 79°35.7'W), vii.1957, W.W. Wirth ( USNM) ; 16♂ 39♀ Porto Chorrera (08°52.8'N 79°47'W), 9.vii.1952, W.W. Wirth ( USNM) .

Type locality: Costa Rica, Guanacaste, Playa Puerto Soley (11°02.5'N 85°40.1'W) .

Distribution: Neotropical: Costa Rica (Guanacaste, Puntarenas), El Salvador (Sonsonate), Panama (Cocle, Darien, Panama).

Remarks: Although similar to P. subnudus in having a high gena, this species differs in having two pairs of interfrontal setae and in characters from structures of the male terminalia, especially the shape of the elongated surstyli.