Phyllophaga bipartita ( Horn, 1887 )

Schnepp, Kyle E., 2019, Three new synonymies in Phyllophaga Harris, 1827 (Coleoptera: Scarabaeidae), with lectotype and neotype designations, Insecta Mundi 742 (742), pp. 1-6 : 3

Phyllophaga bipartita ( Horn, 1887)

Figures 5–6 , 11–12

Lachnosterna bipartita Horn 1887: 242 . Lectotype: MCZ, here designated, male.

Phyllophaga biparita (Horn) : Glasgow 1916: 373.

Phyllophaga falta Sanderson 1950: 92 . New synonymy. Type: INHS, male.

Lachnosterna bipartita was described by Horn (1887) from “ Kansas, Louisiana and Texas.” Glasgow resurrected Phyllophaga in 1916 and included this species in the genus. Phyllophaga falta was described by Sanderson (1950) from a single male collected in Fayetteville, Arkansas ( Fig. 12 ). Externally, P. falta is similar to P. fervida (Fabricius) , as stated by Sanderson (1950), with the only notable difference being the origin of a ridge on the penultimate sternite of the male. This is, however, the same ridge found in some individuals of P. bipartita . There is a wide variation in development of this ridge, from virtually non-existent to heavily sclerotized and projecting to the apex of the segment. Externally, there are no differences between P. falta and some individuals of P. bipartita . There is considerable variation in the development of sclerotized parts of the male genitalia of P. bipartita , as stated by Luginbill and Painter (1953) and Ratcliffe and Paulsen (2008), including projections on the parameres as well as the internal sac. Southwestern populations of P. bipartita have the left paramere (when viewed with parameres face on, as in Fig. 5 ) lacking a strongly hamate structure, instead they look similar to the right paramere. Specimens from the central and eastern portion of this species range have an enlarged hook structure, as well as having a forward projecting process of varying size on the right paramere. The internal sac of P. bipartita is also quite variable, some have a pair of heavily sclerotized patches with a series of spinules on the apex, while others have a lightly sclerotized strip with no spinules where these patches would be. There are also two patches of short spines of varying development on the bottom of the sac at the base; some specimens have patches not unlike those in P. falta . These patches are occasionally strongly developed and each appear as a single large, dark, spinose section. There are also specimens that fall between these two extremes. Phyllophaga falta ( Fig. 6 ) appears to be one of the many variations of P. bipartita , just with strongly reduced parameres. Since the type of P. falta falls within the range of external variation of P. bipartita , the two species are here synonymized.

After examining the type series of L. bipartita , a male lectotype ( Fig. 5 ) is here designated to fix the name to a single specimen to allow comparison to other types. Label data ( Fig. 11 ) are as follows: “Kan. // ♂ // [handwritten label] L./ bipartita/ Horn // MCZ-ENT/ 00008066 // Jan.–Jul. 2005 / MCZ Image/ Database // [on red] TYPE No. [handwritten] 3673/ [handwritten] Lachnosterna / [handwritten] bipartita/ G. H. Horn // [on red] MCZ TYPE/ [handwritten] 8066 // [on red] LECTOTYPE / Lachnosterna bipartita / Horn, 1887 / Det: K. E. Schnepp 2018”.

Figures

Figures 1–6. Male genitalia of Phyllophaga type specimens. 1) Phyllophaga sociata, lectotype. 2) Phyllophaga knausii, lectotype. 3) Phyllophaga rugosa, neotype. 4) Phyllophaga chippewa, holotype. 5) Phyllophaga bipartita, lectotype. 6) Phyllophaga falta, holotype.

Figures 7–12. Specimen labels of Phyllophaga type specimens. 7) Phyllophaga sociata, lectotype. 8) Phyllophaga knausii, lectotype. 9) Phyllophaga rugosa, neotype. 10) Phyllophaga chippewa, holotype. 11) Phyllophaga bipartita, lectotype. 12) Phyllophaga falta, holotype.