Asiolasma schwendingeri, Martens, 2019

Martens, Jochen, 2019, An ancient radiation: Ortholasmatine harvestmen in Asia - a new genus, three new species and a revision of the known species (Arachnida, Opiliones, Nemastomatidae), Revue suisse de Zoologie 126 (1), pp. 79-110 : 101-104

Asiolasma schwendingeri sp. nov.

Figs 1 , 32 , 88-103

Holotype: MHNG; male; VIETNAM, Ha Noi Province, Ba Vi District, Mt Ba Vi (21°04’12’’N, 105°21’55’’E), 900 m, evergreen forest; A. Schulz leg.; 17.5.2012 [sample VN-12/17].

Paratypes: MHNG, 2 males, 2 females ; CJM 8145, 1 male, Mt Ba Vi (21°03’35’’N, 105°22’02’’E), 1000 - 1070 m, evergreen forest; P. Schwendinger & A. Schulz leg.; 16.- 18.5.2012 [sample VN-12/05c ].

Non-types: MHNG; 2 juveniles; Mt Ba Vi (21°03’35’’N, 105°22’02’’E), 1000 -1070 m, evergreen forest; P. Schwendinger & A. Schulz leg.; 16.- 18.5.2012 [sample VN-12/05c] .

Diagnosis: Largest and most long-legged of all Asiolasma species, with rather flat body, anterior part of prosoma including eye mound and hood slightly elevated (la view), visual impression of body massive caused by short hood but slender and fanned tubercles of hood ( Figs 88-93 ); conspicuously long and slender pedipalps only in this species; pedipalpal tibia and tarsus together longer than femur (in both sexes).

Name: The species is dedicated to Dr Peter Schwendinger, esteemed arachnologist, who extensively collected arachnids in Southeast Asia, including specimens of this species and of A. angka . Name in genitive case.

Description

MALE

Body, dorsal side ( Figs 88-89, 91-93 ): Body ( Fig. 92 ) rather flat when seen in la view; Tu oc on anterior margin of prosoma markedly elevated and continuing into short hood; central and distal tubercles of hood parallel to surface of prosoma (la view); hood bearing one central unpaired and three lateral paired tubercles, the basic one shortest, the following ones consecutively longer, the unpaired one longest, all neighbouring ones interconnected by small anvil-shaped bridges close to their bases; tubercles slender, markedly spread, forming an open symmetric palmate fan; on each side of hood one long apophysis projecting from anterior margin of prosoma and closely flanking hood, its tip on a level between 2nd and 3rd tubercle of hood.

Posterior margin of opisthosoma with a row of eight long tubercles of various lengths, parallel-sided and slightly rounded at tips, longest ones in mid-part of row; tubercles close to basis interconnected by bridges of short lateralbasal denticles resulting in small “windows” ( Figs 89, 91 ); fine texture of microtubercles all round.

Network of prosomal and opisthosomal keel cells made of anvil-shaped tubercles low, forming few large cells in anterior part of prosoma, largest ones behind Tu oc, in parts of metapeltidium no closed cells but an irregular double row of tubercles; on opisthosoma large cells on anterior and posterior margin and on lateral sides, in central part of opisthosoma most cells small except for a large central one, always bounded by low anvil shaped tubercles. All cells blackish in color, slightly lighter keels contrasting with dark smooth cuticle.

Body, ventral side: Front and back side of all Cx of legs with row of tubercles, on Cx I pro- and retro-la, Cx II retro-la, Cx III pro- and retro-la, Cx IV retro-la; on Cx I tubercles markedly elevated and anvil-shaped, space between rows of tubercles densely covered with minute pointed denticles; free sternites, corona analis and free tergites bent to ve side, covered with low tubercles and fine microtexture, scattered low setae in between.

Tubercles on Tr: I 1each pro-la and retro-la, II 1 pro-la, 1 retro-la, III 1 pro-la and 1 retro-la, IV 1 pro-la, 1 retro-la. Legs ( Figs 88-89, 91 ): Light brownish, Mt and Ta contrastingly blackish, conspicuously long and slender, no article inflated, covered with densely packed light tubercles and fine setae; long apically rounded tubercles on Cx: I retro-la, II 1 retro-la, III -, IV 1 pro-la, 1 retrola; articles of Ta (male, female in parenthesis; hyphen separating numbers of different individuals, forward slash indicating difference between right and left side of one individual): leg I 5 (5/4), II 5-6 (4/6), III 6 (7), IV 7 (7).

Chelicera ( Fig. 100 ): Basal article slightly tapering distally (la view), dorsally slightly constricted, set with few setae dorsally and prolaterally, no brush of setae, no obvious glandular tissue. Second article with a strong apophysis on upper front, pointed, bent downward. Short to long setae on various parts, mainly on 2nd article.

Pedipalp ( Fig. 102 ): Tr slender, slightly swollen on do side, with two marked tubercles on ve side, each pointed and carrying a strong seta; Fe extremely long and slender, slightly curved downwards, slightly enlarged distally and inflated near insertion of Pt, set with few scattered normal hairs; Pt slightly enlarged and bulge-like ventrally, with a loose field of short setae prolaterally, few clavate setae ventrally, no apparent glandular tissue below; Ti cylindrical and slender, with basal stalk, not curved, clavate hairs on all sides; Ta more slender than Ti, stalked, not inflated on do side, densely covered with clavate setae all round, few long and thin hairs at apex.

Genital morphology ( Figs 94-99 ): Penis very long and slender, about two-thirds of body length, slightly curved, basis slightly broadened, deeply split into two parts, two muscles concentrated there; truncus slender, slightly compressed, parallel-sided (ve/do view), slightly broadened from base (la view) towards glans and further towards stylus (do/ve view), glans spindle-shaped and broadened (la view), stylus short and in strait continuation of glans, with slight helical torsion. Armature of glans with uniformly long spindle-shaped spicules arranged in three groups from distal to proximal: i) six in somewhat irregular annular arrangement, symmetrical on do and ve side, ii) four spicules arranged in a ring, one each on do, ve and la sides, iii) two spicules distinctly separated from group ii, one on each la side.

FEMALE ( Fig. 90 ): Similar to male in general appearance of body, anterior hood and opisthosomal tubercles. Chelicera ( Fig. 101 ) without pointed tubercles on 2nd article; pedipalpal Fe ( Fig. 103 ) with scattered clavate setae ventrally but not in distal quarter; Pt less enlarged than in male, other articles as in male. Tubercles at posterior end of opisthosoma ( Fig. 89 ) shorter than in male and slightly thicker.

Measurements: Body length of individual males: 3.4, 3.4, 3.6 (n=3), of females: 3.7, 3.7 (n=2). Leg II: male, female in parentheses: Fe 3.4 (3.1), Pt 1.0 (0.9), Ti 2.9 (2.9), Mt 1.8. (1.7), Ta 2.0 (1.3). Penis length: 1.3.

Variation: Somatic morphology quite homogeneous, but slight variation in lattice keel network of do side of prosoma discernible.

Relationships: Most similar and geographically closest is A. damingshan from the southern Chinese province of Guangxi. Asiolasma schwendingeri sp. nov. and A. damingshan clearly differ in body size, form of anterior hood, proportions and size of male and female pedipalp, pattern of do keel cells and genital morphology, especially armature of glans penis.

Distribution ( Fig. 1 ): Until now this species is known only from a sole locality in Vietnam, Mt Ba Vi, Ba Vi District, Ha Noi Province. The specimens examined were collected in an evergreen forest between 900 m and 1070 m. Adults as well as small juveniles were found in mid May at the beginning of the southwest monsoon when collecting activity is not yet hindered by heavy rainfall. The distance to the type locality of A. damingshan in Guangxi Province, China, is approximately 425 km in northeast direction.

Figures

Fig. 1. Distributional records of ortholasmatine species in East and Southeast Asia. (1) Asiolasma billsheari sp. nov., China, Gansu, Qinling range. (2) A. juergengruberi sp. nov., China, Yunnan, above Lugu Hu. (3) Same species as before, China, north of Lijiang. (4) A. ailaoshan, China, Yunnan, Ailao Shan. (5) A. damingshan, China, Guangxi, Daming Shan. (6) A. schwendingeri sp. nov., Vietnam, Mt Ba Vi. (7) A. angka, Thailand, Doi Inthanon. (8) Dendrolasma parvulum, Japan, Shikoku Island.

Figs. 31-32. Asiolasma damingshan, male holotype (31) and A. schwendingeri sp. nov., male paratype (32). Body in dorsal view. Scale 1.0 mm. Photographs by P. Schwendinger.

Figs 88-91. Asiolasma schwendingeri sp. nov., dorsal view of male paratype (88, 90-91) and of female paratype (89). (88-89) Entire body. (90) Prosoma. (91) Opisthosoma. Photographs by J. Schmidt.

Figs 92-93. Asiolasma schwendingeri sp. nov., male holotype. (92) Entire body in lateral view. (93) Prosoma in dorsal view. Scale: 0.5 mm (92-93).

Figs 94-103. Asiolasma schwendingeri sp. nov., male holotype (94-100, 102), female paratype (101, 103). (94) Glans penis in lateral view. (95) Same in ventral view. (96) Same in dorsal view. (97) Whole penis in lateral view. (98) Same in ventral view. (99) Same in dorsal view. (100-101) Right chelicera in prolateral view. (102-103) Right pedipalp in prolateral view. Scales: 0.1 mm (94-96); 0.3 mm (100-101); 0.25 mm (97-99); 0.5 mm (102-103).