Leptocera argentinica Buck, 2009

Buck, Matthias & Marshall, Stephen A., 2009, Revision of New World Leptocera Olivier (Diptera, Sphaeroceridae), Zootaxa 2039 (1), pp. 1-139 : 25-27

Leptocera argentinica Buck , new species

( Figs. 2 , 36 , 45–47 , 139 )

Description. Body length 2.1–3.3 mm. Habitus and head as in Figs. 36 and 2 . Coloration lighter than in most other species: Medium brown with frontal vitta, part of face (sometimes), inner surfaces of pedicel and first flagellomere, parafacial and gena (at least in part) reddish yellow; palpus, inner surface of fore coxa, mid trochanter, base of fore femur medially, knees, tibiae (sometimes: especially fore and mid tibia), as well as mid and hind tarsi pale brown. Head and thorax with strong grey pruinosity (better developed than in other species except L. gongylotheca sp.n.). Uppermost orbital setula usually exclinate and more or less reclinate, exceptionally inclinate and proclinate. Arista medium-pubescent. Palpus slender. Mid tibia with bristle above distal dorsal about 0.5–0.6x as long as distal anterodorsal bristle; lowermost bristle of proximal posterodorsal series shorter than lowermost bristle of anterodorsal series; posteroapical bristles short, ventral one slightly to clearly longer than dorsal one.

Male terminalia indistinguishable from L. gongylotheca sp.n. (see Figs. 69–72 ). Sternite 5 with few long bristles posterolaterally, medially in front of field of enlarged microtrichia with small, pale, microtrichose area, hind margin with (4–)5(–6) long, strong scales of subequal length. Epandrium with moderately numerous long bristles ventrally. Anterior section of surstylus with apex of anterior process abruptly bent outward (ventral view), nearly perpendicular to main axis of body, ventral lobe little produced, with few, mostly short bristles. Posterior section of surstylus with fairly long, medially directed, semitransparent process anteriorly at base (best seen in lateral or ventral view); inner margin produced into prominent, rounded angle (posterior view), dorsomedial margin desclerotized, apex with two strong bristles (both with pointed tips but inner one much more tapered), posterior surface with few long, pale hairs in lateral half. Cercus with both finger-like and transparent, lamellate medial processes. Postgonite with wide posterobasal notch ( Fig. 139 ).

Female terminalia ( Figs. 45–47 ): Tergite 7 long and strongly convex, anteriorly with a pair of strong, cruciate bristles; medial stripe in posterior 1/3–2/3 and hind margin shining, lacking tomentosity. Sternite 7 with thickened and narrowly shining hind margin (often difficult to appreciate in slightly teneral specimens). Fused tergite 10 + cerci short, with short hairs. Spermathecae elongate, with transversely ridged basal half and slightly dilated, bumpy distal half.

Type material. Holotype ♀ and 30 ♂♂, 16 ♀♀ paratypes ( CNCI): ARGENTINA, Prov. Tucumán, Arroyo 14 km S El Tala, 700 m, 13–14.x.1968, L.E. Peña. Other paratypes: ARGENTINA. Prov. Buenos Aires: 2 ♂♂, 1 ♀, San Isidro, xi.1975, S. Bolle ( CNCI). Prov. Catamarca: 1 ♀, 6 km N Belén, 1,240 m, 16–31.x.1968, malaise, Willink et al. ( IMLA); 13 ♂♂, 7 ♀♀, Arroyo El Pintado S of La Viña, 650 m, 27–28.ix.1968, L.E. Peña ( CNCI); 3 ♂♂, 1 ♀, same but 27–29.ix.1968, L.E. Peña ( CNCI); 2 ♀♀, 4 km N Santa María, 1,700 m, 4–5.x.1968, L.E. Peña ( CNCI); 4 ♂♂, 1 ♀, El Rincón 4 km N Andalgalá, 1,000 m, 2–3.x.1968, L.E. Peña ( CNCI); 1 ♂, 1 ♀, La Merced , 26.ix.1968, L.E. Peña ( CNCI); 4 ♂♂, 2 ♀♀, 18 km N La Merced, 1,000 m, 26.ix.1968, L.E. Peña ( CNCI); 1 ♀, El Arenal, W Cordillera Aconquija, 2,600 m, 3–4.x.1968, L.E. Peña ( CNCI); 3 ♂♂, 1 ♀, Sumalao, 19.ii.1992, wet muddy area along field, sweep, S.A. Marshall ( DEBU). Prov. Jujuy: 2 ♂♂, 5 ♀♀, Agua Caliente NE Güemes , 1,100 m, 18–19.x.1968, L.E. Peña ( CNCI); 3 ♀♀, Ingenio Ledesma nr. General San Martín, 10.x.1968, L.E. Peña ( CNCI); 9 ♂♂, 11 ♀♀, Perico del Carmen , 21.x.1968, L.E. Peña ( CNCI). Prov. Mendoza: 1 ♀, Cacheta, 23.ii.1953, Aczél & Moyano ( IMLA). Prov. Salta: 1 ♂, 2 ♀♀, Cañada La Gotera , 15 km W Chicoana, 19.ii.1992, sweep wet litter, S.A. Marshall ( DEBU); 9 ♂♂, 12 ♀♀, Río Juramento 60 km S Güemes, 18.x.1968, L.E. Peña ( CNCI); 1 ♂, 1 ♀, Escoipe, 58 km SW Salta, 1,900 m, 8.x.1968, L.E. Peña ( CNCI); 3 ♂♂, 1 ♀, Palo Pintado N San Carlos , 1,900 m, 6.x.1968, L.E. Peña ( CNCI); 1 ♀, Anjuana, 3 km N San Carlos, 5.x.1968, L.E. Peña ( CNCI); 1 ♂, 3 ♀♀, Rosario de Lerma , 24.ii.1992, swept over bulldozed road, S.A. Marshall ( DEBU); 3 ♂♂, 3 ♀♀, same but 29.ii.1992, foul mud, wet vegetation ( DEBU); 1 ♂, same but 24.ii.1992, garbage, mud, creek ( DEBU); 4 ♂♂, 3 ♀♀, same but 29.ii.1992, swept in wet hedgerow ditch ( DEBU); 2 ♂♂, 3 ♀♀, Rosario de Lerma , INESALT yard, 16–28.ii.1992, malaise, S.A. Marshall ( DEBU); 1 ♀, Santa Rosa de Tastil , 3,000 m, 21.ii.1992, very dry along creek, S.A. Marshall ( DEBU); 2 ♂♂, 2 ♀♀, Alto de la Sierra, 1,550 m, 2–30.xii.1987, subtropical humid forest, malaise/FIT, S. & J. Peck ( DEBU). Prov. Tucumán: 3 ♂♂, 2 ♀♀, Río Colorado , 22.ii.1953, R. Golbach ( IMLA); 6 ♂♂, 4 ♀♀, Lacavera, 23–28.xi.1951, Aczél & Golbach ( IMLA); 1 ♀, Yerba Buena, xii.1955, mercury lamp trap, R. Golbach ( IMLA); 3 ♀♀, Aconquija, 18.xii.1949 ( IMLA); 1 ♂, same but 6–10.xii.1950, R. Golbach ( IMLA); Dique Cadillal, 2 ♂♂, 4 ♀♀, 16–29.i.1957, 1 ♀, 16–24.i.1957, R. Golbach ( IMLA); Villa Padre Monti, 4 ♂♂, 2 ♀♀, 17.i–7.ii.1948, 2 ♂♂, 17.i–7.iii.1948, R. Golbach ( IMLA); 1 ♀, B.qdo Julio, 3.x.1926 ( IMLA); 6 ♂♂, 3 ♀♀, 30 km N Tucumán, 700 m, 15.x.1968, L.E. Peña ( CNCI); 3 ♂♂, 2 ♀♀, San Pedro de Colalaeo , 14.x.1968, L.E. Peña ( CNCI). BOLIVIA. Dpto. Santa Cruz: 1 ♀, Aguaclarita nr. Aguaclara, 2.x.1996, Bettella & Rossi ( DEBU); 1 ♀, Río Piray nr. Aguaclara, 3.x.1996, P. Bettella ( DEBU); 2 ♂♂, 1 ♀, La Laguna nr. Pampa Grande, 2.x.1996, W. Rossi ( DEBU, CBFC); 5 ♂♂, 3 ♀♀, Pampa Grande, swamp, Bettella & Rossi ( DEBU). Note: Only exemplars of each series were dissected. Since this species can only be separated from L. gongylotheca sp.n. by the shape of the female spermathecae it is possible that the listed material includes specimens of the latter.

Other material examined ( L. argentinica sp.n. or L. gongylotheca sp.n., males unassociated with females). ARGENTINA. Prov. Buenos Aires: 1 ♂, Arroyo Carnaval, Villa Elisa , 23.xii.1979, C.M. & O.S. Flint ( USNM) . Prov. Catamarca: 2 ♂♂, 16 km E Catamarca, 26.ix.1968, L.E. Peña ( CNCI) ; 1 ♂, Punta de Balasto , 1,900 m, 4.x.1968, L.E. Peña ( CNCI) . Prov. Jujuy: 1 ♂, Cieneguillas, 3,650 m, 28.x.1968, L.E. Peña ( CNCI) . Prov. Salta: 1 ♂, El Maray, 50 km W Chicoana, 2,500 m, 18-28.ii.1992, dry, pan traps, S.A. Marshall ( DEBU) ; 1 ♂, Campo Quijano , 20.ii.1992, forest vestige, sweep, S.A. Marshall ( DEBU) ; 8 ♂♂, El Rey Natl. Pk., Río La Sala , 900 m, 5-10.xii.1987, open streamside in forest, malaise/FIT, S. & J. Peck ( DEBU) ; 1 ♂, El Rey Natl. Pk., Aguas Negras Trail, 900 m, 11-15.xii.1987, forest, malaise/FIT, S. & J. Peck ( DEBU) . Prov. Santa Cruz: 1 ♂, Punta Tumba , 7.ii.1992, pond margin, S.A. Marshall ( DEBU) . Prov. Tucumán: 1 ♂, Tacanas , 3.iii.1948, R. Golbach ( IMLA) ; 1 ♂, El Bañado, 1,700 m, 5.x.1968, L.E. Peña ( CNCI) .

Etymology. This species is named after the country in which most specimens were collected.

Distribution. From east Bolivia (Dpto. Santa Cruz) to southern Argentina (Santa Cruz Province). The species shows a remarkable elevation range (sea level to 3,650 m).

Discussion. This species and the closely related L. gongylotheca sp.n. can be diagnosed by the fairly extensive reddish yellow coloration of the head, the unusually strong pruinosity of the body as well as several details of the male genitalia: apex of anterior process of anterior section of surstylus bent outward rectangularly, inner margin of the latter produced into a prominent rounded angle, lateral one of the two apical bristles of posterior section more pointed than in other species. Except for the completely different shape of the spermathecae we could find no morphological character that separates this species from the sympatric L. gongylotheca sp.n. (see discussion under that species).

Figures

FIGURES 2–6. Leptocera heads and antennae. Heads of (2) L. argentinica sp.n. (Argentina); (3) L. fulva (Costa Rica). Arista and first flagellomeres of (4) L. aequilimbata (Peru); (5) L. neocurvinervis (Chile); (6) L. caenosa (U.S.A.). ad s—additional setulae on orbit, l or—lower orbital bristle, u or—upper orbital bristle.

FIGURES 36–37. Leptocera caenosa group adults: (36) L. argentinica sp.n., male from type locality (Argentina); (37) L. erythrocera pararoralis, male (Ontario, Canada).

FIGURES 45–47. Leptocera argentinica sp.n. (Argentina). Female terminalia: (45) dorsal; (46) spermathecae; (47) ventral. sa—shining area of tergite 7.

FIGURES 138–146. Postgonites and aedeagal complex of Leptocera caenosa group. Postgonites of (138) L. aequilimbata (Argentina), (139) L. argentinica sp.n. (Argentina), (140) L. neocurvinervis (Chile), (141) L. erratica sp.n. (South Africa), (142) L. sphaerotheca sp.n. (U.S.A.), (143) L. ellipsipennis (Juan Fernández Is.), (144) L. parallelipennis sp.n. (Juan Fernández Is.), (145) L. cultellipennis (Juan Fernández Is.). Aedeagal complex of (146) L. duplicata (Juan Fernández Is.). bp—basiphallus, dp—distiphallus, ea—ejaculatory apodeme, pa—phallapodeme, pg—postgonites.

FIGURES 69–75. Leptocera gongylotheca sp.n. (Argentina). Male terminalia (phallus and postgonites omitted): (69) lateral; (70) posterior; (71) ventral; (72) sternite 5. Female terminalia: (73) dorsal; (74) spermathecae; (75) ventral. cp—finger-like process of cercus, da—desclerotized area, proc—process at base of posterior section of surstylus, sa—shining area of tergite 7.