Compsodactylus argentinus ( Moser, 1919 )

Fuhrmann, Juares, 2019, Taxonomy of Neotropical genera Compsodactylus and Dasyus and notes on claw movement in Macrodactylini (Coleoptera: Scarabaeidae: Melolonthinae), Zootaxa 4679 (1), pp. 139-163 : 141-142

Compsodactylus argentinus ( Moser, 1919) ; new combination

( Figs. 1–4 , 10–13, 17–18 , 21–22 , 98 )

Isonychus argentinus Moser, 1919: 41 ; Blackwelder 1944: 230 (checklist); Frey 1970b: 128, fig. 13 (aedeagus); Evans 2003: 275 (checklist); Evans & Smith 2009: 236 (checklist).

Compsodactylus scabrosus Fuhrmann, 2012: 47 ; Figueroa & Neita-Moreno 2019: 588; new synonym.

Diagnosis. Body without metallic reflections; females fusiform in lateral view; elytral striae strongly and regularly punctate; metatibia of males gradually enlarged ( Fig. 12 ); females with inner distal area of gonocoxite rounded.

Description. Emendation to Fuhrmann (2012) description (named as C. scabrosus new synonym). Body ( Figs. 1–2 ) fusiform in dorsal and lateral view; length: 5.1–6.5 mm; greatest width at half of elytra: 2.2–3.2 mm. Dark brown with legs, elytra, and pygidium yellow. Head greatest width: 1.1–1.4 mm; eye small in dorsal view and interocular distance 5 times wider than eye width (measures taken at medial area of eyes). Epistomal suture straight or slightly sinuous. Clypeus with spine-like setae. Pronotum length: 1.7–1.9 mm; greatest width: 1.9–2.2 mm. Elytral striae strongly and regularly punctate. Metathoracic legs of males ( Figs. 11–13 ) with femur slightly enlarged and posterior third with some inner spine-like setae; tibia gradually enlarged, posterior area almost straight ( Fig. 13 ), transverse carina I short and with some stout setae. Parameres as figured ( Figs. 17–18 ). Endophallus ( Figs. 21–22 ) with ventromedial area with asperites.

Remarks. Compsodactylus argentinus and C. parvulus are quite similar to each other, and the former is distinguished as follows (opposition to C. parulus ): clypeus with spine-like setae (with or without); female fusiform in lateral view (dorsoventrally flattened; Fuhrmann 2012: figs. 6, 9); elytra strongly and regularly punctate (shallowly and irregularly punctate); male metatibia progressively enlarged (abruptly enlarged in proximal third) ( Figs. 12, 15 ); gonocoxite inner margin straight (rounded; Fuhrmann 2012: figs. 74–75). The aedeagus is helpful in species determination ( Figs. 17–23 ). Males of C. parvulus are relatively more dorsoventrally flattened than those of C. argentinus ( Figs. 2, 5 ), but this characteristic is much more conspicuous in females.

Distribution. Argentina: Catamarca, Salta, Tucumán ( Fig. 98 ).

Type series. Isonychus argentinus : the species was described based on an undetermined number of specimens. A male lectotype from ZMHU ( Figs. 1–2 ) is hereby designated. Lectotype without external damage; labels ( Fig. 3 ): [ Argentina | Pro. Salta | mtt. 1905 | Steinbach] [ Isonychus | argentinus | Type Mos.] [Berlin] [LECTOTYPE | Isonychus | argentinus | Moser, 1919 | des. J. Fuhrmann | 2014 ♂] [ Compsodactylus | argentinus | ( Moser, 1919) | des. J. Fuhrmann | 2014 ♂]. A male paralectotype was seen from ZMHU with similar labels to the lectotype.

Compsodactylus scabrosus : the species was described based on a male holotype and two male and two female paratypes, one of these females was designated as an allotype. Holotype from CEMT without external damage; labels ( Fig. 4 ): [ ARGENTINA, SALTA | Payogasta iii.1992] [HOLOTYPE ♂ | Compsodactylus | scabrosus | det. J. Fuhrmann, 2012].

Material examined. (9 specimens). ARGENTINA: SALTA, 1905, Steinach (collector), 2 ♂ (lectotype and paralectotype of I. argentinus ) ( ZMHU) , Payogasta , iii.1992, 1 ♂ (holotype of C. scabrosus ) ( CEMT) , 1 ♀, 2 ♂ (paratypes of C. scabrosus ) ( CEMT) ; TUCUMÁN, San Miguel de Tucumán (“Ciudad”), A. Martínez (collector), xii.1948, 1 ♀ (paratype of C. scabrosus ) ( MZSP) ; CATAMARCA, Andalhualá, Willik-Terán (collector), 20.ii.1967, 1 ♂, 1 ♀ ( CEMT) .

Figures

FIGURES 1–8. Compsodactylus. 1–3, Compsodactylus argentinus male lectotype (dorsal, lateral, labels); 4, labels of C. scabrosus male holotype (= C. argentinus); 5–6, C. parvulus male (dorsal, lateral); 7, C. parvulus female holotype labels; 8, labels of mislabeled male of C. parvulus. Scale = 1 mm.

FIGURES 9–20. Male appendages. 9, Dasyus collaris metacoxa; 10, Compsodactylus argentinus metacoxa; 11, C. argentinus apex of metatibia; 12, C. argentinus metafemur and tibia; 13, C. argentinus tibia, posterior view; 14, C. parvulus apex of metatibia; 15, C. parvulus metafemur and tibia; 16, C. parvulus tibia, posterior view; 17–18, C. argentinus aedeagus (lateral and parameres in dorsal view); 19–20, C. parvulus aedeagus (lateral and parameres in dorsal view). cxk, coxa-katepisternum articulation; cxp, coxopleural articulation; cxt, coxa-trochanter articulation; mbd, marginal bead; mip, metacoxal inner process (limit in dotted line). Scale = 1 mm.

FIGURES 21–23. Compsodactylus. 21, Compsodactylus argentinus temones, dorsal; 22, C. argentinus endophallus, ventral (asperites details with relative magnification of 3x); 23, C. parvulus endophallus, ventral (asperites details with relative magnification of 3x). Scale: 0.2 mm.

FIGURES 98–99. South America distributional records. 98, Compsodactylus; 99, Dasyus. Scale = 500 km.