Cryptocercus relictus Bey-Bienko 1935

 

<한국 기록>

● Asahina S. 1991. Notes on two small collections of the Blattaria from China and Korea. Akitu 121: 1-5.

 

Original description: Cryptocercus relictus Bey-Bienko 1935

  ♂. Very similar in general appearance and principal morphological features to the single known representative of the genus, viz. C. punctulatus Scudd. from N. America but much smaller and heavier.
  Body smooth, shining with scattered puncturation. Head flattened, scarcely visible from above, face smooth, puncturation denser and more delicate than on the upper surface of the body; eyes not projecting, ocelli completely absent; maxillary palpi very short, apical (fifth) joint a little longer than forth, third joint subequal in length to apical, distal truncation of the apical joint practically euqal to half the length of that joint.
  Puncturation of pronotum denser and deeper than on the other tergites; anterior transverse concave area between elevated anterior margin and the begining of the deep median longitudinal depression with small but very distinct granules, longitudinal depression near its posterior end touching with a very distinct and short transverse linear depression, T-shaped. Meso- and metanotum, as well as all abdominal tergites including the sixth (apical) tergite only delicately punctured, without minute rounded projections. Sixth tergite triangularly produced, apex rounded; sixth sternite similar in the shape to the six tergite but somewhat larger. Supraanal plate, cerci and subgenital plate concealed, completely enveloped by the sixth tergite and sternite; supraanal plate of the same type as in
C. punctulatus Scudd. but lateral margins not sinuated, straight in their apical tow thirds, more convergent apically, the apex narrowly rounded; cerci as in C. punctulatus; subgenital plate as broad as the supraanal plate, hind margin with two distinct lateral emarginations from which relatively small cylindro-conical and quite similar styli arise, the hind margin between these styli distinctly undulate, with not strong, rounded, obtuse median emargination; the distance between the styli distinctly greater than width of the produced triangular part of the supraanal plate.
  Legs as in
C. punctulatus, but heavier and differ in the number of spines; anterior femora with 2-5 subapical spines on anterior lower margin and with 2-3 spines on posterior lower margin, dorsal genicular spines absent; all other femora without subapical spines or the middle femora, with only one spine on anterior lower margin; dorsal genicular spines on median and posterior femora developed but very small.
  ♀. Resembling the male sex in all external features excepting the shape of the sixth ventral segment, which is characterized by presence of two feeble but distinct rounded excisions on lateral margins before the apex, hind margin between these excisions truncate or with very feeble rounded excision of the same type as two subapical excisions; this feature permits to determine the sex without removing the six ventral abdominal segment. Supraanal plate concealed as in the male sex, and quite similar in form and structure; subgenital plate absent.
  General coloration uniformly shining brownish-black or almost black but specimens which probably have recently moulted, as well as the larvae are dark reddish-brown; lower surface slightly lighter, with a distinct dark-reddish-brown shade.
  Length of body ♂ 17-21, ♀ 18.3-23.5, pronotum ♂ 5-5.6, ♀ 5.5-6.2, maximum width of pronotum ♂ 7.2-7.5, ♀ 7.5-9.2, length of hind femora ♂ 3.7-4, ♀ 3.8-4.2 ㎜.
  This extremely interesting insect differs strongly from
C. punctulatus in its smaller and heavier body, structure of maxillary palpi and pronotum, in quite distinct type of puncturation, in a presence of small but distinct genicular spines on the middle and hind femora; this last mentioned feature usually has in Blattodea a generic importance but all other structural features and the general appearance of both species are so similar that I hesitate at present to separate C. relictus into an independent genus.
  The discovery of an Asiatic representative of the genus
Cryptocercus has a very great zoogeographical importance and shows a very remarkable distribution of the genus. I do not want at present to speculate on the reasons of such distribution but it shows that the genus Cryptocercus belongs to a very ancient group of animals and its present disjointed area is a relic of former wide distribution.
  Two female specimens from the Szechuan prov., China, differ from the Ussurian and Manchurian specimens in larger size and in more coarsely punctured lateral parts of abdominal tergites and of the whole surface of the sixth tergite; it is very probable that they belong to an independent species but I hesitate to describe a new species on the female sex alone.