Mesomerodon gilletti Soula, 2008

Seidel, Matthias, Jameson, Mary L. & Stone, Rachel L., 2017, A new cryptic species and review of the east-Andean leaf chafer genus Mesomerodon Ohaus, 1905 (Coleoptera, Scarabaeidae, Rutelinae), ZooKeys 671, pp. 61-85 : 69-70

Mesomerodon gilletti Soula, 2008 Figs 4-5, 8, 9-13, 16-17, 18, 23, 26

Mesomerodon gilletti Soula, 2008: 21 (original combination)

Type material.

Holotype male, allotype female, and eight paratypes (four male, four females. Holotype male at CCECL with label data: a) "Tena (E), 9/91, (750m)" (handwritten), b) male genitalia card mounted c) "Holotype, 2007, Mesomerodon gilletti S., Soula" (typeset and handwritten on red label). Allotype female at CCECL with label data: a) "Tena (E), 9/91, (750m)" (handwritten), b) "Allotype, 2007, Mesomerodon gilletti S., Soula" (typeset and handwritten on red label). Paratype male at CCECL with label data: a) "Tena (E), 9/91, (750m)" (handwritten), b) male genitalia card mounted, c) "Paratype, 2007, Mesomerodon gilletti S., Soula" (typeset and handwritten on red label). Paratypes (2 females) at CCECL with label data: a) "Tena (E), 9/91, (750m)" (handwritten), b) "Paratype, 2007, Mesomerodon gilletti S., Soula" (typeset and handwritten on red label). Paratypes (2 males) at CCECL with label data: a) "Misahuali (E.), 5/91" or "Misahuali (Eq.), 5/91" (handwritten), b) male genitalia card mounted, c) "Paratype, 2007, Mesomerodon gilletti S., Soula" (typeset and handwritten on red label). Paratype male at CCECL with label data: a) "EQUATEUR: Prov. NAPO, MISAHUALLI ile ANACONDA, Alt. 350 m.; 17-22.9.1990, Leg. Joss" (typeset), b) male genitalia card mounted, c) "Paratype, 2007, Mesomerodon gilletti S., Soula" (typeset and handwritten on red label). Paratypes (2 females) at CCECL with label data: a) "Misahuali (E.), 5/91" (handwritten), b) "Paratype, 2007, Mesomerodon gilletti S., Soula" (typeset and handwritten on red label).

Description

(based on 50 males and 19 females). Length from apex of clypeus to apex of pygidium 18.0-20.0 mm (♂) and 21.0-24.0 mm (♀); width at mid-elytra 10.0-11.0 mm (♂) and 12.0-14.0 mm (♀). Legs: Protarsomere 2 of male lacking well-defined striae at ventral apex (Fig. 26). Male genitalia (Figs 23): Parameres with elongate, narrow projection (=stem) and with nearly obsolete impressed longitudinal fissure (Fig. 23a); stem broad, not narrowed toward apex, subapex lacking paired, spinose projections; ventral sclerite of phallobase with surface concave, apex quadrate (Fig. 23c); lateral view diagnostic (Fig. 23b).

Diagnosis.

Mesomerodon gilletti males are differentiated from other Mesomerodon species by the following combination of characters: Protarsomere 2 of male ventrally with striated region poorly defined or lacking at apex (striated in M. spinipenne ; lacking in M. barclayi sp. n.; [Figs 25-27]) and parameres, and ventral sclerite of phallobase (Fig. 23 versus Fig. 24 in M. spinipenne and Fig. 22 in M. barclayi sp. n.). Mesomerodon gilletti females can only be confidently determined when associated with male specimens from the same collecting event.

Distribution

(Fig. 18). Known from western (lowland) Amazonia in Ecuador and Colombia (new country record). The species occurs in apparent sympatry with M. barclayi sp. n. A record of ' Mesomerodon species 1' from Napo Province in Paucar-Cabrera (2005) probably represents a record of Mesomerodon gilletti . Records of Mesomerodon from Ecuador ( Blackwelder 1944, Ohaus 1918, 1934, 1952, Machatschke 1972, Moore et al. 2017, Paucar-Cabrera 2005) are records for either M. gilletti or M. barclayi sp. n.

Locality data

(Suppl. material 1). 69 specimens from 12 collections.

COLOMBIA: Putumayo

ECUADOR: Napo, Orellana, Sucumbíos

Temporal data.

Based on label data, this species is known to be active in the months of February, May, June, August, September, October, and November.

Natural history.

Based on label data, adult M. gilletti are found associated with lights at night. Immature stages are unknown.

Remarks.

Soula (2008) named this species based on twelve specimens, dedicating the species to Conrad Gillett (then at the BMNH) who provided specimens for Soula’s study. In overall appearance, M. gilletti was not discernable from M. spinipenne except for the "parameres that are different enough to justify the status of the species in its own right" ( Soula 2008).