Mesomerodon spinipenne Ohaus, 1905

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 : 70-73

Mesomerodon spinipenne Ohaus, 1905 Figs 6, 7, 14, 18, 24, 27

Mesomerodon spinipenne Ohaus, 1905: 320-321 (original combination).

Type material.

Lectotype male (designated by Soula 2008) and three paralectotypes (1 male, 2 females). Lectotype male at ZMHB with label data: a) "bei Pozuzu, Eckardt S." and "O. Peru, Chuchurras" (handwritten on verse and obverse), b) " Mesomerodon spinipenne , Type ♂ Ohs." (handwritten on red label), c) "SYNTYPUS, Mesomerodon spinipenne Ohaus, 1905, labelled by MNHUB 2007" (typeset on red label), d) male genitalia card mounted, e) "Lectotype Mesomerodon spinipenne Oh., 2007 Soula" (typeset and handwritten on red label). Paralectotype female at ZMHB with label data: a) “60.” (handwritten, one egg mounted), b) "BRAZIL R.Purus" (typeset), c) " Mesomerodon spinipenne ♀, Cotype Ohs." (handwritten on red label), d) "SYNTYPUS, Mesomerodon spinipenne Ohaus, 1905, labelled by MNHUB 2007" (typeset), e) "Paralectotype 2007, Mesomerodon spinipenne Oh. Soula det." (typeset and handwritten on red label). Paralectotype female at ZMHB with label data: a) "Chuchuras, Amazonas" (handwritten), b) " Mesomerodon spinipenne , Cotype ♀ Ohs." (handwritten on red label), c) "SYNTYPUS, Mesomerodon spinipenne Ohaus, 1905, labelled by MNHUB 2007" (typeset on red label), d) "Paralectotype 2007, Mesomerodon spinipenne S., Soula det." (typeset and handwritten on red label). Paralectotype male deposited at BMNH with label data: a) "Chuchurras Peru" (handwritten), b) "Ohaus determ., Mesomerodon spinipenne Ohs." (typeset and handwritten), c) "Peru 1907 •27” (handwritten), d) “Co-type” (typeset on round yellow label), d) “♂” (typeset), e) “Cotypus!” (typeset on red label), f) male genitalia card mounted, g) "Paralectotype, Mesomerodon spinipenne , Ohaus, 1905, M Seidel des. 2016" (typeset on red label).

Ohaus (1905: 321) stated that the type series included at least one male and at least one female (but likely at least two females based on the length/width range that Ohaus provided) from "Peru Chuchuras (Eckhard); Amazonas, Rio Purus." We found one additional male syntype at the BMNH that fits the measurements provided by Ohaus (1905), and we labeled it as a paralectotype. It is possible that additional paralectotypes may be found in collections.

Description

(based on 52 males and 161 females). Length from apex of clypeus to apex of pygidium 17.0-20.0 mm (♂) and 19.0-24.0 mm (♀); width at mid-elytra 10.0-12.0 mm (♂) and 11.0-14.0 mm (♀). Legs: Protarsomere 2 (♂) with well-defined striae at ventral apex (Fig. 27). Male genitalia (Fig. 24): Parameres with elongate, narrow projection (=stem) and with longitudinal, impressed fissure (Fig. 24a); stem broadened abruptly at apex, subapex with paired, spinose projections (almost appearing broken); ventral sclerite of phallobase with surface concave, apex quadrate (Fig. 24c); lateral view diagnostic (Fig. 24b).

Diagnosis.

Mesomerodon spinipenne males are differentiated from other Mesomerodon species by the following combination of characters: Protarsomere 2 with well-defined striae at ventral apex (Fig. 27) (lacking striae in M. gilletti and M. barclayi sp. n.; Figs 25-26) and form of the parameres, and form of the ventral sclerite of the phallobase (Fig. 24 versus Fig. 23 in M. gilletti and Fig. 22 in M. barclayi sp. n.). Females can only be confidently determined when associated with male specimens from the same collecting event. Females occurring in Bolivia and Peru are most likely conspecific with M. spinipenne (Figs 6-7).

Distribution

(Fig. 18). Mesomerodon spinipenne is the most broadly distributed species in the genus, and it occurs from central Peru to central Bolivia in the western (lowland) Amazonia (from 230 to 762 m elevation). The species has been recorded from Brazil, "Rio Purus" ( Blackwelder 1944, Ohaus 1905, 1934, 1952, Machatschke 1972, Krajcik 2008, Soula 2008, Moore et al. 2017), but in our view this is an erroneous record. The record is based on a paralectotype female collected at the Rio Purus that rises in the Uyacali Region in Peru and flows into Brazil and which could, therefore, have been collected either in Peru or Brazil. Based on our examination of 213 specimens, we think that this specimen represents a Peruvian locality. Records of the species from Ecuador ( Blackwelder 1944, Ohaus 1918, 1934, 1952, Machatschke 1972, Moore et al. 2017, Paucar-Cabrera 2005) are incorrect. These are records for either M. gilletti or M. barclayi sp. n.

Locality data

(Suppl. material 1). 213 specimens from 18 collections.

BOLIVIA: Cochabamba (Chapare), Huánuco ( Blackwelder 1944, Ohaus 1905, 1918, 1934, 1952, Machatschke 1972, Soula 2008, Ratcliffe et al. 2015), Junín ( Blackwelder 1944, Ohaus 1905, 1918, 1934, 1952, Machatschke 1972, Soula 2008, Ratcliffe et al. 2015), Pasco ( Blackwelder 1944, Ohaus 1905, 1918, 1934, 1952, Machatschke 1972, Soula 2008, Ratcliffe et al. 2015), Santa Cruz (Ichilo, Sara)

PERU: Ayacucho (La Mar), Cusco (Quispicanchi), Huánuco (Leoncio Prado, Puerto Inca), Madre De Dios ( Manú, Tambopata), Pasco (Oxapampa), Ucayali (Padre Abad), Santa Cruz ( Blackwelder 1944, Ohaus 1918, 1934, 1952, Gutiérrez 1951, Machatschke 1972, Moore et al. 2017).

Temporal data.

Based on label data, this species is known to be active in all months except January and February.

Natural history.

Based on label data, adult M. spinipenne are active at night and can be collected at lights. Immature stages are unknown.

Remarks.

Based on body measurements provided by Ohaus (1905), we conclude that he had a minimum of 3 specimens: 1 male (length 18.5mm, width 10.5mm) and 2 females (length 22-23.5mm, width 12.5-13.5mm) from two localities (Chuchuras and Rio Purus). The lectotype specimen at ZMHB was designated by Soula (2008), and it is a male specimen labeled by Ohaus as “type” (" Mesomerodon spinipenne , Type ♂ Ohs.") and with the locality label "bei Pozuzu, Eckardt S." and "O. Peru, Chuchurras". As part of this research, we found and labeled specimens that were invalidly labeled as type specimens and that do not belong to the type series (see "Type Specimens").

It is possible that the specific epithet, " spinipenne ", refers to the apex of the elytra in the male which possess an apical spine or tubercle. The Latin root “spini” refers to spine or thorn, and the Latin root “penna” refers to wing. This character state is not unique to M. spinipenne ; instead, it is a synapomorphy for all species in the genus.