Dachtylembia siamensis Poolprasert

Poolprasert, Pisit, 2014, Dachtylembia, a new genus in the family Teratembiidae (Embioptera) from Thailand, Zootaxa 3779 (4), pp. 456-462 : 458-462

Dachtylembia siamensis Poolprasert , sp. nov.

( Figs. 2 –4)

Diagnosis. Males of Dachtylembia are distinguished by the following characteristics of the abdominal terminalia: lines of fusion of 10L, 10R, and MS still evident as shallow, weak grooves, 10R with outer side short, tapered laterally; 10LP elongated, slightly constricted medially then evenly tapered with small outer hook at the apex; LCB with only a single inner process protruding like a finger; inner side of RC1 relatively simple. Females without significant characters.

Material examined. Holotype male, 8 paratype males, 5 paratype females ( CUMNH), Thailand, Tak province, Mae Sod district, hill evergreen forest, 16°45.838’N, 098°54.543’E, elev. 943 m, 26.VI.2009; 1 male ( CUMNH), Chaiyaphum province, Thep Sathit district, deciduous dipterocarp forest, 15°37.683’N, 101°23.323’E, elev. 681 m, 0 7. IX. 2008; 1 male, 1 female ( CUMNH), Chiang Mai province, Sanpatong district, hill evergreen forest, 18°32.217’N, 098°31.377’E, elev. 1258 m, 0 3. III. 2008; 1 male ( CUMNH), Lampang province, Ngao disrtict, mixed deciduous forest, 18°46.361’N 99°58.123’E, elev. 412 m, 12.XII.2008; 1 male ( CUMNH), Loei province, Phu Ruea district, hill evegreen forest, 17°29.907’N 101°20.483’E, elev. 1196 m, 21. II. 2008; 1 male ( CUMNH), Petchabun province, Nam Nao district, mixed deciduous forest, 16°44.963’N 101°27.833’E, elev. 711 m, 12.II.2008; 1 male, 2 females ( TNHM), Khao Kho district, hill evergreen forest, 17°00.276’N 100°59.672’E, elev. 1153 m, 0 5. IX. 2009; 1 male ( CUMNH), Phitsanulok province, Nakhon Thai district, hill evergreen forest, 16°52.466’N, 100°49.672’E, elev. 1133 m, 11.XII.2012; 1 male ( TNHM), Ubon Ratchathani province, Khong Chiam district, deciduous dipterocarp forest, 17°12.839’N, 102°08.176’E, elev. 230 m, 24. II.2008. All specimens collected by P. Poolprasert.

Distribution. This species is only known in western, northern and northeastern Thailand

Etymology. The specific epithet refers to the region of first discovery: Siam, former name of the Kingdom of Thailand.

Description. Alate male (n = 9, mean (range) ± SD): Head width × length 0.7 (0.6–0.8) ± 1.13 × 0.9 (0.8–1.0) ± 0.45 mm, body length 6.2 (6.0–6.4) ± 1.05 mm, width 0.7 (0.6–0.8) ± 0.53 mm, forewing length 3.8 (3.7–5.9) ± 0.41 mm, hindwing length 3.3 (3.2–3.4) ± 0.19 mm.

Head capsule elongate-oval, dark. Eyes dark lavender. Submentum trapezoidal with shallow medial concave anterior magin. Mandible dark and slender. Antennae short, brownish throughout, 16-segmented. Thorax brownish throughout. Wings light brown with AM not forked. All legs entirely brownish. Hind leg with only one basitarsal papilla. Abdomen light brown with terminalia paler. Terminalia with forward projection of MS extending one-third length of ninth tergite (9), apex rounded. 10LP slender, straight-sided and parallel-sided then constricted medially and slightly narrowed caudally with apex dorsally furrowed. Inner lobe of LCB finger-like, tapered distally leftward. LPPT sclerotized, without outer hook. 10LP broad basally then tapered terminally with small outer hook at apex. 10 RP long, broad, gradually narrowing caudally, with mostly membranous inner margin. LC1 very broad basally then slightly constricted to distal tip.

Apterous female (n = 5, mean (range) ± SD): Head width × length 0.7 (0.6–0.8) ± 0.27 × 1.0 (0.9–1.1) ± 0.35 mm, body length 6.4 (6.3–6.5) ± 0.17 mm, width 0.7 (0.6–0.8) ± 0.29 mm.

Head capsule dark, longer than wide. Eyes smaller and less reniform than in male. Antennae brown throughout, 14-segmented. Thorax brownish throughout. All legs same color as thorax. Hind leg with only one basitarsal papilla. Abdomen cylindrical, brown throughout. Tenth sternite symmetrically divided longitudinally into two lateral plates. Cerci entirely medium brown.

Remarks. This new species is very difficult to see in nature because its gallery is small, concealed beneath pulverized bark particles and fecal pellets. Most of the nests were also found under foliose lichens ( Fig. 2 C). Females tend to be solitary in their galleries with their young.

FIGURE 4. Illustrations of Dachtylembia siamensis n. gen., n. sp. (A) Head of male. (B) Terminalia (dorsal) of male. (C) Terminalia (ventral) of male. (D) Hind basitarsus of male.. (E) Sternites of female. Abbreviations: 8 (T8, S8) = eighth abdominal tergite/sternite; 9 (T9, S9) = ninth abdominal tergite/stergite; 10L and 10R = hemitergites of the tenth segment; 10LP and 10 RP = left and right tergal processes; EP = epiproct (segment 11); H = hypandrium (sternite 9); HP = hypandrium process; LPPT = left paraproct; LC1 and LC2 = first and second segments of left cercus; left cercus basipodite (LCB); left cercus-basipodite process (LCBP); RC1 and RC2 = first and second segments of right cercus; SMT = submentum.

Discussion. According to Ross (2007), diversity of Embioptera in southeastern Asia is high, particularly so in Thailand. Teratembiidae was also included in a dichotomous key to the families and subsequently, teratembiids were reported as an oriental group. However, no species of this family was listed for this geographic area; therefore, Dachtylembia gen. nov. is considered the first known teratembiid in Thailand. Morphological characteristics of the new genus place it in Teratembiidae ; however, the cladistic analysis has demonstrated that some species in Teratembiidae (e.g., Teratembia geniculata Krauss, 1911 ) and Oligotomidae ( Haploembia solieri (Rambur, 1842) , Aposthonia glauerti (Tillyard, 1932) , A. gurneyi (Froggatt, 1904) and Oligotoma saundersii (Westwood, 1837)) are closely related ( Szumik, 1994). The phylogenetic relationship of these two families including this new species should be reconstructed for further study.

Figures

FIGURE 2. Dachtylembia siamensis n. gen., n. sp. (A) Male. (B) Female. (C) Silk gallery.