Swammerdamella amacuzacae, Huerta, Heron & Dzul, Felipe, 2013

Huerta, Heron & Dzul, Felipe, 2013, First record of the genus Abrhexosa Freeman from Mexico, with the description a new species, and two new species and new records of the genus Swammerdamella Enderlein (Diptera: Scatopsidae), Zootaxa 3693 (1) : -

Swammerdamella amacuzacae sp. nov.

( Figs 4 A–B, 5A, 6)

Type material. Holotype male, labelled: Morelos, Mpio. Puente de Ixtla, Localidad El Estudiante, a 150 mts. del río Amacuzac, 870 msnm, abril-2011, trampa Malaise, Col. Huerta, H., dissected, in CAIM. Paratypes: 2 males, same data as holotype; 3 males: Mexico, Guerrero, Ayutla de Los Libres, Localidad La Unión, cercano a la localidad, Rancho “El Camalote”, Trampa Malaise, 24-Abr-1997, Col. W. Bibiano Marín, in CAIM.

Other material examined. 1 male: Mexico, Guerrero, Cutzamala de Pinzón, Río Cutzamala, 16-IX-1983, cebo humano, 10:20 AM, Col. S. Ibáñez-Bernal.

Diagnosis. Male: This is the only Neotropical species with sternite 7 V-shaped ( Fig. 5 A), aedeagal plate with posterior margin truncate; penis valve rounded; tergite 6 quadrate.

Description. Male. Head dark brown. Eyes with interommatidial spicules; antenna with 7 flagellomeres, uniformly dark brown; pedicel subcylindrical, similar in length to the first flagellomere; flagellomeres I to VI wider than long, distal flagellomere club-shaped, longer than the others flagellomeres; flagellum length, 0.17 mm; palpus brown, stout, reniform, pointed, sensilla scattered, length, 0.10 mm; labellum light brown, setose; cardo-stipes with 5 setae.

Thorax. Dark brown. Scutum covered with sparse short setae, 9 supra-alar setae; anterior spiracular sclerite with 24 setae; anterior part of anepiternum with 9 setae; 6 sub-alar setae; anterior part of katepisternum with 2 setae; posterior spiracular sclerite with 3 setae. Legs ( Fig. 6 ) brown; coxae dark brown; fore and mid femur dark brown, hind femur brown, wider on 1/3 basal; tibiae brown, fore tibia darker, a pale spot on middle of fore and mid tibiae, hind tibia with a pale ring medially; tarsi pale yellow, fore tarsi darker.

Wing length 1.0 mm, width 0.46 mm; hyaline, membrane entirely covered with dense, minute, light micropilosity; radial veins short, extending 0.41 of wing length, light brown; 7 dorsal setae on basal portion of R, 6 dorsal setae on R4+5, 1 dorsal setae on R1; posterior veins translucent; fork of M with branches diverging markedly only near apex of wing; false vein faint.

Abdomen: Dark brown; tergite 6 quadrate, length, 0.22 mm, width, 0.26 mm; sternite 6 simple. Segment 7 ( Fig. 4 A), similar to other species, length 0.19 mm. Tergite 7 ( Fig. 5 A) length, 0.09 mm, width, 0.19 mm; anterior margin rounded; posterior margin concave, with usual median process, truncate apically, and one apical process shorter and more sclerotized. Sternite 7 ( Fig. 5 A) V-shaped, length, 0.14 mm, width, 0.24 mm; sclerotized in middle. Genital capsule ( Fig. 4 B), length, 0.14 mm, width, 0.15 mm, gonocoxite (sensu Cook, 1956) long, fingershaped; aedeagal plate with truncate posterior margin; penis valve (sensu Cook, 1956), rounded with posterior margin sclerotized, bearing scattered setae.

Female. Unknown.

Distribution. Neotropical. Mexico (Guerrero and Morelos).

Etymology. The name amacuzacae refers to the river Amacuzac, flows through Morelos state.

Discussion. Swammerdamella amacuzacae is clearly related to other known Neotropical species of the genus. Of these, Swammerdamella grogani Huerta & Ibáñez-Bernal and Swammerdamella glochis Cook are the ones more similar to the new species. S. amacuzacae differs from S. grogani by the intersegmental membrane of segment 7, without lateral specialized group of setae, the gonocoxite long, digitiform, and the sternite 7 V-shaped. S. glochis Cook , has sternite 7 U-shaped, with triangular gonocoxite and anterior margin of tergite 7 slightly pointed.

Figures

FIGURE 4. Swammerdamella amacuzacae sp. nov. Male, A – B; Swammerdamella amorimi sp. nov. Male, C – F. A, C. Segment 7, ventral view; B, D. Genitalia, ventral view; E. Tergite 6, dorsal view; F. Sternite 6, dorsal view.

FIGURE 5. Segment 7. Male. Ventral view. A. Swammerdamella amacuzacae sp. nov.; B. Swammerdamella amorimi sp. nov.

FIGURE 6. Swammerdamella amacuzacae sp. nov. Male. Legs. Lateral view. A. Fore leg, B. Mid leg, C. Hind leg.