• Journal of Ecology and Environment
• /
• v.31 no.2
• /
• pp.97-105
• /
• 2008

Subsocial behavior of the genus Cryptocercus cockroaches has been believed as primitive traits of termite eusociality. Thus, it has been believed that understanding Cryptocercus subsociality is a pre-requisite stage to infer evolutionary route of the eusociality in termites. Woodroaches of Cryptocercus are also well known because of its peculiar characteristics including adults living monogamously in pairs, semelparous reproduction, xylophagy, obligatory association between adults and their offspring, slow development, and anal trophallaxis by adults. Based on the previously accumulated data, we try to understand two major components of Cryptocercus life history, development and reproduction. We hypothesize that harsh winter and length of winter might be one of the main causes driving the appearance of the delayed development and semelparous reproduction in Cryptocercus life history.

• Animal Systematics, Evolution and Diversity
• /
• v.22 no.1
• /
• pp.23-27
• /
• 2006

Subsocial woodroaches of Cryptocercus occur in high mountainous forests in temperate regions and they live in a family in complicated galleries of rotten logs. A prominent feature of the geographical distribution of Cryptocercus is the wide disjunction between the eastern and western species in North America, and between West China and Northeast Asia. Recently, five species of the genus were added from Asian areas and two of them are distributed in Northeast Asian areas. We examined morpho-anatomical structures of male genitalia in Manchurian and Korean Cryptocercus, focusing on male genital hooks and subgenital plates.

• Journal of Ecology and Environment
• /
• v.30 no.4
• /
• pp.331-340
• /
• 2007

We examined the evolutionary and ecological processes shaping current geographical distributions of a Korean wood-eating cockroach species, Cryptocercus kyebangensis. Our research aims were to understand evolutionary pattern of DNA sequences, to construct genetic network of Cryptocercus kyebangensis local populations and to understand evolutionary and ecological processes shaping their current geographical distribution patterns via DNA sequence information and genetic networks, using sequence data of two genes (ITS-2 and AT region) from local populations of C. kyebangensis. The results suggest that the ITS-2 and AT region are appropriate molecular markers for elucidating C. kyebangensis geographic patterns at the population level. The MSN-A based on the ITS-2 showed two possible routes, the Hwaak-san and Myeongji-san route and the Seorak-san and Gyebang-san route, for migration of ancestral C. kyebangensis into South Korea. The MSNs (MSN-A and -B) elucidate migration routes well within South Korea, especially the route of Group I and Group II.

• Animal Systematics, Evolution and Diversity
• /
• v.22 no.1
• /
• pp.17-22
• /
• 2006

Cryptocercus nymphs periodically groom ventral surface of their parents. The grooming might be licking-behavior to obtain secretions from the ventral surface of their parents, and some essential nutrients or hormones that facilitate nymphal development might be included in the secretions. We tried to find morphological structures for secretion outlets on the ventral surface. The deep depressions around setae were present, and their shape was an external morphological structure that liquid secretions from internal glands are likely to be well seized. There were also small holes on the depressions that might be external openings for secretions from the sternal glands. Another possible region on body surface for outlets of secretions might be the apophyses. In Cryptocercus individuals, mucous liquid on body surface was relatively highly present around coxa. The intercoxal apodemes, to which muscles are attached and which open externally between the mid and hindcoxae, might have evolved a secondary function of producing nourishment for the young.

• Animal cells and systems
• /
• v.7 no.2
• /
• pp.111-117
• /
• 2003

Ecological aspects of Cryptocercus kyebangensis life history were investigated via laboratory rearing and field observations. The number of antennal segments and head width were used to classify the first four instars. The results, which combine both the field collection and the laboratory rearing, indicate that eleven instars occur in C. kyebangensis. It supports the proposal on the number of instars of Park and Choe (2003c) based on field collections. A total of 388 nymps from 13 colonies were collected prior to winter to investigate overwintering stages. Of them,4％ (n = 17) were the second instars, 57％ (n = 220) were the third instars, and 39％ (n = 151) were the fourth instars, respectively. Thus, most of them overwinter in the third or fourth instars. The results indicate that young nymphs of C. kyebangensis have to reach at least 3rd or 4th instar to survive low temperature environment of winter. According to seasonal dynamics of populations, C. kyebangensis reaches adulthood in the summer of the fourth or fifth year (4-5 yr span) after their birth.

• Animal cells and systems
• /
• v.7 no.2
• /
• pp.105-109
• /
• 2003

Morphological characteristics of nymphal instars are described for a Korean wood-feeding cockroach, Cryptocercus kyebangensis. Eleven instars, including adults, were tentatively identified. Female adults had apicolateral emargination and a truncated apical median prominence in the seventh sternite, and female nymphs of the other instars except for the last had a narrowly rounded apical median prominence in the seventh sternite. In the last instar, the seventh sternite was partially desclerotized and somewhat shriveled at the start of the emarginated area. In contrast, males showed no emargination in adults, and had a rounded broad apical median in this area of all instars. In the ninth sternite, female nymphs had a medium notch on the caudal margin and styli were separated before reaching adulthood, whereas no such notch was observed in male nymphs. The styli remained prominent in the ninth sternite of male adults.

• Proceedings of the Zoological Society Korea Conference
• /
• 2003.08a
• /
• pp.46-46
• /
• 2003

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
• /
• 2000.04a
• /
• pp.91.2-91
• /
• 2000

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
• /
• 2000.04a
• /
• pp.91.1-91
• /
• 2000

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
• /
• 2000.10a
• /
• pp.97.1-97
• /
• 2000

No Abstract, See Full Text