Homolophus martensi ( Staręga, 1986 )

Snegovaya, Nataly Yu. & Cokendolpher, James C., 2021, Further studies on harvestman genus Homolophus (Opiliones: Phalangiidae), with descriptions of two new species, Zootaxa 4908 (3), pp. 301-353 : 335-337

Homolophus martensi ( Staręga, 1986)

Figures 11 , 25–26

Euphalangium martensi Staręga, 1986: 133–135 , figs. 5–10

Homolophus martensi — Staręga, 2003: 96; Staręga 2013: 41

Diagnosis. The species differs from all species, including the most closely related, H. nordenskioeldi (L. Koch, 1879a) and H. tibetanus ( Roewer, 1911) , by the following: characterized by genital morphology and by body coloration. Penis with wide base, narrows gradually to thin glans. Glans slender, in lateral view not wedge-shaped, distally bluntly ended (almost squared-off), slightly wider distally than basally; in dorsal view elongated, not oval, only slightly wider at center. Center of abdomen with broad (about 1/3 of width) light-colored strip bordered with darker regions. Short thickened legs, femur II very slightly longer (1.03 times) than abdominal width.

Type Locality. China, Xîzàng (East Tibet) .

Distribution. China, Xîzàng (Tibet) ( Fig. 11 ).

Specimens Examined. CHINA, Xîzàng (Tibet), Da-par-Yun tract, Kam ( East Tibet), 3962 m a.s.l., September 1900 (1 male, ZIN) ; Xîzàng (Tibet), Dza-Chu River ( Mekong ) (5 males, 3 females, ZIN) . Lake Rhombo Mtso , 3962 m a.s.l., August 1900 (1 male, ZIN) ; Duserku vill., 3475 m a.s.l., August 1900 (1 male, ZIN) .

Description. Medium-sized harvestmen; male body rectangular, with rounded corners; medium sclerotization of body cuticle, slender, 1.73 times longer than wide, length 5.2 mm, width 3.0 mm; color yellowish-gold to dark brown (some places almost black) with spots of light and dark color (especially over muscle attachment sites (compare to Fig. 1A ); over body, center of abdomen with broad (about 1/3 of width) light-colored strip bordered with darker brown regions. Dorsum, along borders of tergites, with single-double row of small denticles. Preocular area and on lateral sides of cephalothorax with scattered small, black-tipped denticles. Ocularium low, oval, not large, 1.1 times its length from anterior margin of cephalothorax, with 5–7 denticles on each side. Legs short, angular in cross-section, Fe I and III thickened, segments of legs with transverse rows of denticles. Leg lengths (mm): I 1.7 + 2.4 + 2.2 + 2.6 + 4.2 = 13.1, II 3.1 + 1.5 + 3.0 + 3.0 + 7.3 = 17.9, III 2.5 + 1.3 + 2.3 + 3.2 + 4.2 = 13.5, IV 3.5 + 1.3 + 2.8 + 3.0 + 6.0 = 16.6. Pedipalp segment lengths (mm): 1.8 + 0.7 + 0.8 + 1.5 = 4.8. Pedipalp with numerous denticles (sexually dimorphic): Fe ventrally densely covered with medium-sized denticles and setae, dorsally with several denticles and setae; Pa dorsally with denticles and setae, laterally and ventrally with setae; Ti ventrally and dorsally with denticles and setae, laterally with setae; Ta ventrally with row (4 denticles wide) of sensory microdenticles, dorsally and laterally with setae. Chelicerae enlarged (sexually dimorphic) with some tabby marks, basal segment dorsally with many denticles, distal segment anteriorly with densely arranged fine denticles. Cheliceral basal segment ventrally smooth without bulge, length 1.9 mm, distal segment length 2.1 mm. Penis short, dorsoventrally flattened, bowed, recurved in lateral view, truncus with wide base, gradually narrows to glans in distal half. Glans slender, in lateral view not wedge-shaped, distally bluntly ended (almost squared-off), slightly wider distally than basally; in dorsal view elongated, not oval, only slightly wider at center. Penis length (mm): truncus 2.9, glans 0.4, stylus 0.1

Female differs from male in more rounded, longer, body shape; in absence of tubercles on chelicerae and pedipalp (note: only 1–2 denticles distally on femur), and dense arrangement of denticles on cephalothorax. Body rectangular, with rounded corners; less slender, 2.0 times longer than wide. Female body length 5.0 mm, width 2.5 mm. Leg lengths (mm): I 1.6 + 0.9 + 1.5 + 1.5 + 3.5 = 9.0, II 2.3 + 1.0 + 2.0 + 2.0 + 6.2 = 13.5, III 1.7 + 0.8 + 1.5 + 1.6 + 3.8 = 9.4, IV 2.5 + 1.0 + 2.0 + 2.8 + 5.8 = 14.1. Pedipalp segment lengths (mm): 1.8 + 1.0 + 1.3 + 2.4 = 6.5. Cheliceral basal segment length 2.8 mm, distal segment length 3.3 mm.

Comments. Specimens over 100 years old. Colors likely faded. Not same species as Euphalangium martensi Das & Bastawade, 2006 (= junior homonym of Homolophus martensi Staręga, 1986 ) that was given replacement name of Homolophus bastawadei Staręga, 2013 . Homolophus bastawadei is only known from India.

Figures

FIGURE 1. Homolophus anatomy, males: A, kozlovi sp. nov., body, dorsal showing muscle attachment sites in black (color photograph Fig. 23); B, gobiensis outline of body showing denticles (compare Fig. 21A); C, betpakdalensis denticles (compare Fig. 12A); D, pallens denticles (compare Fig 30C); E, chemerisi leg I metatarsus with characteristic thickly packed “brushes” of short setae at higher magnification (see insert); F, albofasciatus denticles (compare Fig. 3A); G, nordenskioeldi (from Murmansk) penis, dorsal; muscle presence more evident in magnified sections. Scale lines: A–D, F = 1 mm; E = 0.5 mm, insert greatly magnified, G = 0.25 mm.

FIGURE 11. Distribution of some Homolophus species in the Palearctic: Central and East Asia. Data for pale colored symbols (red without black dot) taken from literature; identifications not verified.

FIGURE 25. Homolophus martensi (Staręga, 1986): A, male body, dorsal; B, male ocularium, dorsal; C, female body, dorsal; D, female ocularium, dorsal; E, male right chelicera, ectal; F, male right chelicera, mesal; G, female right pedipalp, ectal; H, female right pedipalp, mesal; I, female left chelicera, mesal; J, female left chelicera, ectal; K, male right pedipalp, mesal; L, male right pedipalp, ectal.

FIGURE 26. Homolophus martensi (Staręga, 1986), male: A, femur I, dorsal; B, penis, lateral; C, penis glans, lateral; D, penis, dorsal; E, penis glans, dorsal.