Dead-twig discrimination for oviposition in a cicada, Cryptotympana facialis (Hemiptera: Cicadidae)

Abstract

In phytophagous insects, in spite of some general advantages of oviposition on a vital part of their host food plants, certain species prefer dead tissues for oviposition. In the present study, we examined oviposition-related behaviors of a cicada, Cryptotympana facialis (Walker), which lays eggs exclusively into dead twigs. From behavioral observation of females experimentally assigned to live or dead plant material, we found that egg laying into freshly cut live twigs is abandoned in two phases, i.e. before and after initiation of egg nest-creating behavior with the ovipositor. Behavioral sequence analyses revealed that oviposition was generally preceded by rubbing with the rostrum tip and brief stylet-penetration behavior, suggesting that oral assessment may play a primary role in decision-making of oviposition in the earlier discriminating phase. From the similarity in behavioral flows of this assessment to vital tissue-seeking behaviors, cicada females are presumed to judge a twig as dead by sensing the absence of vital cues. These findings contribute to understanding a behavioral basis of dead plant recognition for oviposition, potentially giving an insight into ecological and evolutionary aspects of diverse oviposition preferences.

Reforestation provides a foraging habitat for brown bears (Ursus arctos) by increasing cicada Lyristes bihamatus density in the Shiretoko World Heritage site

“…Several annual cicada species in Japan lay their eggs on dead branches attached to living trees (e.g. Cryptotympana facialis (F. Walker, 1858), Moriyama et al (2016)). In the study site, oviposition scars by L. bihamatus were frequently observed on dead branches of the living larch trees (K. Tomita personal observation), suggesting that this species also deposits its eggs on the dead branches of living trees.…”

Disentangling the direct and indirect effects of canopy and understory vegetation on the foraging habitat selection of the brown bear Ursus arctos

“…A possible reason for the positive effect of the larch plantations on cicada nymph density might be the fact that larches harbor more oviposition sites for cicadas than broadleaved trees. Cicada species in Japan usually lay eggs on dead branches attached to living trees (Moriyama et al 2016). Conifer plantations usually have more attached dead branches than natural forests (Yoshida and Hijii 2006).…”

The formation of a hatching line in the serosal cuticle confers multifaceted adaptive functions on the eggshell of a cicada

“…In contrast to C. facialis , some temperate cicada species use a strategy of hatching within the oviposition year, without overwintering in diapause [ 31 , 53 , 62 , 63 ]. In addition, although C. facialis lays eggs in dead twigs [ 33 ], some other cicadas choose live plant tissues for oviposition [ 64 , 65 ]. Their eggs appear to encounter various moist environments and are unlikely to hatch in response to humidity cues, implying that they might face different types of adaptive demands than C. facialis .…”

“…Cryptotympana facialis normally lays eggs in dead twigs of woody plants (Fig. 1 a) [ 33 ]. In order to obtain loose eggs, the collected adult females were wrapped in a wet paper towel as described previously [ 34 ].…”

“…In this study, we present a unique feature that is found in eggshells of cicadas and enables these insects to meet the conflicting demands of their embryonic lives. Cicada eggs are laid into a small hole made in plant tissues by a spear-shaped ovipositor [ 31 – 33 ]. A remarkable feature of the eggs of temperate cicadas is the extremely long duration of the egg stage; in some species, the egg period reaches up to 12 months [ 31 , 34 , 35 ].…”