Soldier caste with morphological and reproductive division in the aphid tribe Nipponaphidini

Abstract

We investigated demographic, morphological and histological aspects of Distylaphis foliorum, a gall-forming nipponaphidine aphid from Java, Indonesia, whose first instar nymphs had been reported to have enlarged forelegs and attack other insects. The gall inhabitants of D. foliorum consisted of two discrete populations; one developing normally and the other remaining at the first instar. Morphometric analysis identified two types of first instar nymphs; nymphs with relatively long forelegs and slender abdomen, and nymphs with relatively short forelegs and fat abdomen. The former nymphs were found from both young galls and mature galls, while the latter nymphs were from young galls only. Histological analysis strongly suggested a reproductive division in the first instar. In the former nymphs from mature galls, ovaries and mycetomes were degenerate and replaced by well-developed fat body cells. These results indicated that D. foliorum has a morphologically differentiated sterile soldier caste in the first instar. This study is the first report of a soldier caste with morphological and reproductive division in the aphid tribe Nipponaphidini, and suggests that highly specialized soldier castes have evolved at least four times in aphids.

Formation of long‐lasting galls by overwintered nymphs in the Japanese aphid Quadrartus yoshinomiyai (Hemiptera: Aphididae: Hormaphidinae)

“…), one of which produces a morphologically specialized, sterile caste (Fukatsu & Antonius ; Fukatsu et al . ). In addition, self‐sacrificial gall repair and post‐reproductive colony defense, previously unknown social behaviors in aphids, have recently been reported (Kurosu et al .…”

“…The tribe Nipponaphidini, which forms galls on Distylium trees and contains several unique social species, provides an important clade for understanding the evolution of sociality in aphids. The presence of defensive nymphs has been reported in the gallinhabiting generation of six species (Kurosu et al 1995(Kurosu et al , 2003Aoki et al 1998;Fukatsu & Antonius 1998;Fukatsu et al 2000;Uematsu et al 2007), one of which produces a morphologically specialized, sterile caste (Fukatsu & Antonius 1998;Fukatsu et al 2005). In addition, self-sacrificial gall repair and postreproductive colony defense, previously unknown social behaviors in aphids, have recently been reported (Kurosu et al 2003;Kutsukake et al 2009;Uematsu et al 2010).…”

“…Although life cycles of nipponaphidine aphids are poorly known, their galling phase on the primary host has been studied to some extent (Sorin 1960(Sorin , 1997Nishitani & Ito 1991;Ngakan & Yukawa 1996;Fukatsu et al 2005). Galls of nipponaphidine aphids are completely closed until they grow to maturity, and then develop exit holes, allowing winged adults to fly to their secondary hosts, mainly evergreen trees such as Quercus, Castanopsis, or Neolitsea (Blackman & Eastop 1994), where their progeny form open colonies.…”

A new genus and two new species of galling aphids (Hemiptera: Aphididae) from Distylium (Hamamelidaceae) in Taiwan

“…Some investigations have provided molecular and other evidence for reconstructing the phylogenetic relationships of Hormaphidinae, and the monophyly of Nipponaphidini is supported (Huang et al, 2012;Chen et al, 2014). Others have brought about taxonomical and cecidological knowledge of nipponaphidine aphids (Monzen, 1929(Monzen, , 1934(Monzen, , 1954Takahashi, 1962;Sorin, 1987;Noordam, 1991;Kurosu et al, 1995;Aoki et al, 1999Aoki et al, , 2015Fukatsu et al, 2005).However there have been fewer cecidological studies of the galls on nipponaphidine aphids than of those of the other two hormaphidinae tribes (Chen et al, 2014).…”

Extremely Long-Closed Galls of a Social Aphid

“…The tribe includes several social species that produce defensive nymphs in the galls [11][12][13][14][15]. About a dozen nipponaphidines are known to form galls on Distylium racemosum in Japan [16,17].…”