Morphometric variability and life history traits of the rare Paramogoplistes novaki in comparison to Mogoplistes brunneus (Orthoptera: Mogoplistidae)

Abstract

SummaryIn this study, morphometric and life history traits were compared between two species of scaly crickets – Paramogoplistes novaki (Krauss, 1888) and Mogoplistes brunneus Serville, 1838. Crickets were collected along the Krčić River in SE Croatia using pitfall traps. In total, 37 P. novaki and 105 M. brunneus specimens were included in the analyses. Diagnostic traits such as total body length and pronotum length to width ratio proved to be unreliable particularly in differentiating females of the two species. On the other hand, subgenital plate shape turned out to be useful in distinguishing P. novaki from M. brunneus in all stages. Several new differential morphometric traits were found in adults – subgenital plate length, width and length to width ratio. Higher variability of morphometric traits between the sexes was recorded in M. brunneus than in P. novaki, one of the cues indicating possible neotenic origin of the latter. The activity period of P. novaki was shorter and more autumn-oriented than the activity period of M. brunneus. Their surface activity maxima exhibited clear temporal separation, likely to avoid competition due to niche overlapping. Sex ratio was female-biased in both species, pronouncedly so in M. brunneus, probably indicating higher activity of females due to more frequent foraging and/or seeking for oviposition sites. The current study represents a step forward in understanding morphometric variability and life history of these two little-known scaly cricket species.