Zarcosia lemairei, Gompel, 2020

Gompel, Nicolas, 2020, Synopsis of the Asian species in the genus Zarcosia Collado & Alonso-Zarazaga 1996 with new combinations and descriptions of fourteen new species, Zootaxa 4838 (2), pp. 151-178 : 163-164

Zarcosia lemairei n. sp.

( Figures 1 ; 3a,b ; 4i ; 5 a–d; 6a)

Etymology. The species is named after Jean-Michel Lemaire, who sent me the first specimens of this species, thereby seeding the present synopsis.

Type locality. Laos: Khammouan province, Boualapha, Tham Nam Ock [17°35’ N 105°50’ E] .

Distribution. Laos, Myanmar, Vietnam ( Figure 1 ).

Description. ( Figure 3 a–b). Body length. ♂: 3.70± 0.28 mm (n=6); ♀: 3.98± 0.29 mm (n=12). Entirely black, slender, with long appendages. Body shape reminiscent of strict cave beetles ( Carabidae : Trechini or Leiodidae : Leptodirini ). Pubescence dense, very short, almost pulverulent, composed of stout bristles arising from the punctation, interspersed with very short whitish hairs, arising from the entire body surface, and giving a mat appearance to the insect.

Head ( Figure 5 a–c). As wide as pronotum in dorsal view. Eyes bigger in males than in females. Palpi black, last article securiform, as broad as the length of the first two antennomeres together. Frons deeply carved in males, flat in females. The deep pit on the male forehead differs in shape from that of Zarcosia palliditarsis (Pic, 1912) ( Figure 5 e–g) and possesses a long and wavy tuft of silky yellow bristles, borne from the bottom of the head pit.

Antennae. Filiform, 20% longer than elytra in males, hardly longer than elytra in females.

Pronotum. Slightly longer than wide. Sides convergent in their anterior third, otherwise roughly parallel to each other, with a slight sinuosity or constriction. The dorsal surface is regularly rounded, with an anterior gibbosity. Combined, the anterior gibbosity and the slight posterior constriction place the largest width of the pronotum in its anterior third.

Base of the pronotum with two sinuosities: one at the level of the midline and two flanking this first one, on each side. Sexual dimorphism: in males, the dorsal surface is posteriorly impressed by ill-defined foveola that singles out a carena-like bulge along the midline.

Elytra. ♂: 2.61± 0.18 mm (n=6); ♀: 2.71± 0.21 mm (n=12). 2.3 longer than wide in both sexes, with sides slightly but regularly curved in females, straight, convergent in their posterior half in males. Dorsal surface moderately convex.

Legs. Black, except the second half of the penultimate and the last tarsal segment that are orange in both sexes. Surface of femora micro-reticulated. Sexual dimorphism: (i) Tibias of forelegs and hindlegs slightly thickened and sinuated in males, flattened on their inner face; (ii) first tarsal segments of mesothoracic legs thickened in males ( Figure 5d , left); (iii) hindtarsae extraordinarily elongated in males, in particular the last segment, which is 50–70% the length of the first tarsal segment ( Figure 5d , right). By contrast, in females, the last segment of the hindtarsae is 40% the length of the first tarsal segment.

Aedeagus. Figure 4i . Slender, narrow, sides weakly convergent in dorsal view. Slight curvature in lateral view, with apex sharply bent upward.

Type material. Holotype (♂, MNHN). Laos: Khammouan province, Boualapha, Tham Nam Ock, Cave , Hin Nam No Project , 17°35’ N 105°50’ E (270 m) (H. Steiner) 3.III.2016 . Paratypes. Laos: Ban Du, Tham Pha Houm , cave, 17°33’ N 105°49’ E (170 m) (J. Lips) 1.III.2016 (2 ♂ paratypes, NGPC; 3 ♀ paratypes, JMLC) ; Nong Ping, Tham Pha Pong , cave, 17°21’ N 105°54’ E (226 m) (J. Lips) 25.II.2016 (1 ♀ paratype, JMLC) ; Vientiane Province, Vang Vieng, Tham Ling Kham, Cave , 18°56’ N 102°26’ E, by hand (L. Johansson) 18.II.2004 (1 ♀ paratype, MNHN) ; Vientiane, Tham Paka , 19°01’ N 101°53’ E, cave (M. Ferrand) 5.III.2016 (1 ♂ and 1 ♀ paratypes, JMLC) ; Khammouan province, Boualapha , Tham Nam Ock, Cave , Hin Nam No Project , 17°35’ N 105°50’ E (270 m) (H. Steiner) 3.III.2016 (1 ♀ paratype, NGPC) ; Khammouan province, Boualapha, Tham Xe Bangfai, cave , Hin Nam No Project , 17°22’ N 105°50’ E (270 m) (H. Steiner) 22.II.2016 (1 ♀ paratype, NGPC) ; Myanmar: Shan State, Mondawa Gu , cave, 22°12’ N 95°52’ E, by hand (F. Brehier) 1.XII.2015 (1 ♀ paratype, MNHN) ; Vietnam: Hà Nam Ninh Province, Cúc Phuong, Water Fairy cave , 20°18’ N 105°36’ E, by hand (L. Deharveng) 11.X.1998 (1 ♀ paratype, NGPC) ; Bắc Kạn Province, Ba B ể District, Hoàng Trĩ, Nà sai, Tham Phay Cave , 22°19’ N 105°38’ E (490 m) ( A. Faille) 22.X.2018 (1 ♂ paratype, SMNS; 1 ♂ paratype, NGPC) ; Quang Binh, Cha Noi, Hang Cha Noi , 17°38’ N 106°06’ E (260 m), by hand, (L. Deharveng and A. Bedos) 8.I.1995 (1 ♀ paratype, MNHN) ; Quang Binh, Dong Hoi, Grotte de Troc , 17°39’ N 106°14’ E (70 m), by hand (L. Deharveng and A. Bedos) 15.III.1997 (1 ♀ paratype, MNHN) .

Figures

FIGURE 1. Distribution of Zarcosia species across South Asia. New taxa are indicated in boldface. For Z. lemairei n. sp., the broader geographical range is highlighted with a red area with a dotted line.

FIGURE 3. Habitus of new Zarcosia species. a, Z. lemairei n. sp., ♂ holotype, from Laos. b, Z. lemairei n. sp., ♀ paratype, from Laos. c, Z. ilonae n. sp., ♂ holotype, from Thailand. d, Z. gerstmeieri n. sp., ♂ holotype, from Vietnam. e, Z. weigeli n. sp., ♂ holotype, from China (Yunnan). f, Z. deharvengi n. sp., ♂ holotype, from Republic of Indonesia (Sumatra). g, Z. sumatrensis n. sp., ♂ holotype, from Republic of Indonesia (Sumatra). h, Z. sumatrensis n. sp., ♀ paratype, from Republic of Indonesia (Sumatra). i, Z. barclayi n. sp., ♂ holotype, from Malaysia. j, Z. barclayi n. sp., ♀ paratype, from Malaysia. k, Z. schawalleri n. sp., ♂ holotype, from Malaysia. l, Z. schawalleri n. sp., ♀ paratype, from Malaysia. m, Z. bedosae n. sp., ♂ holotype, from Laos. n, Z. sinuata n. sp., ♂ holotype, from Thailand. o, Z. sinuata n. sp., ♀ paratype, from Thailand. p, Z. spinifemur n. sp., ♂ holotype, from Sri Lanka. q, Z. dentatifemur (Pic, 1912), ♂ holotype, from Sri Lanka, after remounting (same specimen as in Fig. 2o). r, Z. srilankaensis n. sp., ♂ paratype, from Sri Lanka. s, Z. intermedia n. sp., ♂ paratype, from Sri Lanka. s, Z. brunnea n. sp., ♂ paratype, from Sri Lanka. Scale bars: 0.5 mm.

FIGURE 4. Aedeagus of selected Zarcosia species. a, Z. barclayi n. sp., holotype, from Malaysia, lateral and dorsal views. b, Z. bedosae n. sp., holotype, from Laos, lateral and dorsal views. c, Z. bipartita (Pic, 1901) from India, lateral view. d, Z. cephalica (Pic, 1901) from Republic of Indonesia, lateral view. e, Z. deharvengi n. sp., holotype, from Laos, lateral and dorsal views. f, Z. gerstmeieri n. sp., holotype, from Vietnam, lateral and dorsal views. g, Z. ilonae n. sp., holotype, from Thailand, lateral and dorsal views. h, Z. kempi (Blair, 1924), holotype, from India, lateral and dorsal views. i, Z. lemairei n. sp., holotype, from Laos, lateral and dorsal views. j, Z. obscuricornis (Pic, 1927) from Vietnam, lateral view. k, Z. palliditarsis (Pic, 1912) from Sri Lanka, lateral view. l, Z. picina (Fairmaire, 1893), lectotype, from Vietnam, lateral view. m, Z. rubrobasalis (Pic, 1921) (slight uncertainty on the identity of this specimen) from Singapore, lateral view. n, Z. schawalleri n. sp., holotype, from Malaysia, lateral and dorsal views. o, Z. sinuata n. sp., holotype, from Thailand, lateral and dorsal views. p, Z. sumatrensis n. sp., holotype, from Republic of Indonesia (Sumatra), lateral and dorsal views. q, Z. troglodytes (Champion, 1916), holotype, from Malaysia, lateral view. r, Z. weigeli n. sp., holotype, from China (Yunnan), lateral and dorsal views. s, Z. spinifemur n. sp., holotype, from Sri Lanka, lateral and dorsal views. t, Z. dentatifemur (Pic, 1912), holotype, from Sri Lanka, lateral and dorsal views. u, Z. srilankaensis n. sp., paratype, from Sri Lanka, lateral and dorsal views. v, Z. intermedia n. sp., paratype, from Sri Lanka, lateral and dorsal views. w, Z. brunnea n. sp., paratype, from Sri Lanka, lateral and dorsal views. Scale bars: 100 µm.

FIGURE 5. Morphological details of selected Zarcosia species. a–d, Z. lemairei n. sp., ♂ holotype, from Laos: head in lateral (a), frontal (b) and dorsal (c) views; mesothoracic (left) and metathoracic (right) tarsae (d). e–g, Z. palliditarsis (Pic, 1912), ♂, from Sri Lanka: head in lateral (e), frontal (f) and dorsal (g) views. h, Z. srilankaensis n. sp., ♂ paratype, from Sri Lanka: tuft of pubescence at elytral apex. i, Z. weigeli n. sp., ♂ holotype, from China (Yunnan): elytral pubescence on disc. j, Z. gerstmeieri n. sp., ♂ holotype, from Vietnam: elytral pubescence on disc. k–t: male forelegs of Z. ilonae n. sp., holotype, from Thailand (k); Z. deharvengi n. sp., holotype, from Republic of Indonesia (Sumatra) (l); Z. schawalleri n. sp., holotype, from Malaysia (m); Z. sinuata n. sp., holotype, from Thailand (n); Z. sumatrensis n. sp., holotype, from Republic of Indonesia (Sumatra) (o); Z. srilankaensis n. sp., paratype, from Sri Lanka (p); Z. intermedia n. sp., paratype, from Sri Lanka (q); Z. dentatifemur (Pic, 1912), holotype, from Sri Lanka (r); Z. brunnea n. sp., paratype, from Sri Lanka (s); Z. weigeli n. sp., holotype, from China (Yunnan) (t). u–x: male mesothoracic legs of Z. cephalica (Pic, 1901) from Republic of Indonesia (u); Z. gerstmeieri n. sp., holotype, from Vietnam (v); Z. dentatifemur (Pic, 1912), holotype, from Sri Lanka (w); Z. spinifemur n. sp., holotype, from Sri Lanka (x). Scale bars: 100 µm.