Progomphus complicatus Selys, 1854

Molineri, Carlos, Rodríguez, José Sebastián, Leiva, Marta & Márquez, Javier Andrés, 2023, Diagnoses and key for the larvae of Progomphus Selys, 1854 from Argentina (Anisoptera: Gomphidae), with first larval descriptions for P. aberrans Belle, 1973 and P. kimminsi Belle, 1973, Zootaxa 5297 (2), pp. 239-259 : 244-246

Progomphus complicatus Selys, 1854 ( Figs. 3–4 )

Reared material. ARGENTINA: 3 female adults with larval exuviae (IBN-O-1124, IBN-O-1300, IBN-O-1430) from Tucumán, Tapia, río Tapia , puente RN9, 26.61046° S, 65.26338° W, 668 m, 19/Dec/2021 (collected) , 17/ Jan/2022 (emerged) , C. Molineri & G. Fontanarrosa leg.; 1 male adult with associated exuvia (IBN-O-1302), same data except date 29/Dec/2022 .

Other material. ARGENTINA: 2 larvae (IBN-O-92, IBN-O-93) from Tucumán, El Boyero, arroyo Pozo del Pescado , 26.18948° S, 65.28417° W, 784 m, 17/Dec/2022, C. Molineri & J.S. Rodríguez leg. ; 1 larva (IBN-O-91) from Jujuy, Caimancito, río San Francisco (bajo puente de Aguas Calientes ), 23.71166° S, 64.53444° w, 360 m, 17/Nov/2014, E. Dominguez & C. Molineri leg. ; 6 larvae (IBN-O-95) from Jujuy, Caimancito, Río Zora por ruta interna, 23.77222° S, 64.61250° W, 385 m, 07/Aug/2014, J.S. Rodríguez leg. ; 9 larvae (IBN-O-94) same data ; 5 larvae (IBN-O-99) from Tucumán, Acheral, Citrícola, Arroyo Hollinado , 27.11722° S, 65.45661° W, 359 m, 28/ Jul/2006 , C. Molineri et al. leg.; 5 larvae (IBN-O-97) same data ; 1 larva (IBN-O-96) same data except 15/Sep/2008 ; 1 larva (IBN-O-98) from Tucumán, Acheral, RP 38, río Aranillas , 27.11643° S, 65.45904° W, 359 m, 28/Jul/2006 , Molineri et al. leg .; 2 larvae (IBN-O-100) from Tucumán, El Boyero, arroyo Pozo del Pescado , 26.18948° S, 65.28417° W, 784 m, 27/Oct/2017, C. Molineri, J. Márquez & J.S. Rodríguez leg.

Larval diagnosis. Progomphus complicatus can be separated from other larvae in the genus by the following combination of characters: fourth antennomere relatively long and slender ( Fig. 4b ); mandibular formula ( Figs. 3a–b ) L 1 2 3 4 0 a (m 1,2,3, 4) b, R 1 2 3 4 y a (m 1,2) b; galeolacinia with 4 ventral teeth, the first one very reduced, shorter than ½ length of the second ( Fig. 3c ), palp acute apically; prementum subrectangular ( Fig. 3f ), ligula without submedian tubercles, margin with two rows of flat setae, short and blunt on ventral row, much longer and acute with irregular margin in the dorsal row ( Fig. 3e ); lateral margins of prementum with 4 short and 1 long spines submedially, and 1 short spine apically ( Fig. 3f ); labial palp with smooth margins, inner apical projection subtriangular reaching basal 1/3 of movable hook, movable hook stout slightly shorter to outer palpal margin; fore claws cheliform, meso- and hindtarsal claws normal (long and acutely pointed, flattened), hind claw with a subapical seta; thorax and legs with blackish setae; without tibial distal spurs; hind tarsi darker than the rest of the leg; posterolateral spines present on S5–9 ( Fig. 4d ); relatively large acute dorsal tubercles on terga S2–9 ( Fig. 4e ); sterna S2–8 formed by three plates (a large central one, and two smaller laterally), sterna S1 and S9–10 formed by one plate ( Fig. 4d ); apical abdominal segments and anal pyramid elongated, relative length of sternite S8: S9: S10: epiproct = 1.1: 1.1: 1: 1.1.

Santos (1968) described the larval stage of P. complicatus , but association of adults was only by supposition (i.e., shared locality). We have reared 3 females and 1 male adults from larva that confirm the larval—adult association. We provide above some data and illustrations, not mentioned in the original description that now have proven to be useful to distinguish the species (e.g., mandibular formula, shape and arrangement of maxillary teeth, and other details of abdomen). Among the Argentinean species, P. complicatus is similar to P. aberrans and P. kimminsi , because all of them present a slender, subcylindrical distal antennomere, absence of tibial spurs, and S5 with posterolateral spine. Nevertheless, the larva of P. complicatus can be easily separated from them by its short anal pyramid (vs long and slender in the other two species), and by the absence of posterolateral spine on S4 (present in the other two species).

Distribution: Argentina (Catamarca, Jujuy, Misiones, Salta, Tucumán, Lozano et al. 2020) and Brazil ( Belle 1973; Almeida et al. 2013; García et al. 2019).

Figures

FIGURE 3. P. complicatus Selys, female last instar larval exuvia: a, left mandible, occlusal view; b, right mandible, occlusal view; c, maxilla, ventral view (arrow indicates first tooth); d, same, dorsal view; e, detail of flat marginal setae on ligula; f, prementum, ventral view.

FIGURE 4. P. complicatus Selys, female last instar larval exuvia: a, dorsal habitus; b, antennae, dorsal (number indicate 4th antennomere); c, “normal” fore tarsal claws, lateral; d, abdomen, ventral; e, abdomen, lateral.