Miopsalis dillyi, Schmidt & Clouse & Sharma, 2020

Schmidt, Stephanie M., Clouse, Ronald M. & Sharma, Prashant P., 2020, A new Miopsalis from Mindanao supports a biogeographic umbilicus between Borneo and the southern Philippines (Arachnida: Opiliones: Cyphophthalmi: Stylocellidae), Zootaxa 4779 (3), pp. 379-390 : 381-385

Miopsalis dillyi sp. nov.

( Figs. 1–4 , Tables 1–2)

Types. Male holotype (NMP) from Center for Environmental Development and Recreation (CEDAR), Impalutao, Impasug-ong, Bukidnon Province, Mindanao I., Philippines, 767 m alt. (8.254894°N, 125.035732°E), leg. D. Mohagan, D.J.B. Mohagan, V. Yamba, D.E.M. General, R.M. Clouse, 3 July 2014, from sifted leaf litter. Two male (both dissected for genitalia) and one female paratypes in 96% EtOH (MCZ 154598), same collecting data as for holotype; 1 male mounted on SEM stubs ( MCZ 154599 ), same collecting data as for holotype . One male and 2 female paratypes in 96% EtOH ( MCZ 154600 ) from Center for Environmental Development and Recreation ( CEDAR), Impalutao , Impasug-ong , Bukidnon Province, Mindanao I., Philippines, 775 m alt. (8.254933°N, 125.035749°E), leg. D. Mohagan, V. Yamba, R. M. Clouse, 30 June 2014, from sifted leaf litter. One male and 2 female paratypes in 96% EtOH ( MHNG) from Center for Environmental Development and Recreation ( CEDAR), Impalutao, Impasug-ong , Bukidnon Province, Mindanao I., Philippines, 775 m alt. (8.254933°N, 125.035749°E), leg. D. Mohagan, V. Yamba, R. M. Clouse, 30 June 2014, from sifted leaf litter. One male paratype (1 dissected for genitalia) in 96% EtOH ( MCZ 154601 ) from western slope of Mt. Kitanglad , Lantapan, Kaatoan , Bukidnon Province, Mindanao I., Philippines, 1300 m alt. (8.072258°N, 125.008909°E), leg. A. Mohagan, D. Mohagan, D.J.B. Mohagan, V. Yamba, R. M. Clouse, 1 July 2014, from sifted leaf litter. Two female paratypes (extracted for DNA) in 96% EtOH ( MCZ 154602 ) and 1 female paratype on SEM stubs ( MCZ 154603 ), from western slope of Mt. Kitanglad , Lantapan, Kaa- toan , Bukidnon Province, Mindanao I., Philippines, 1300 m alt. (8.072258°N, 125.008909°E), leg. A. Mohagan, D. Mohagan, D.J.B. Mohagan, V. Yamba, R. M. Clouse, 1 July 2014, from sifted leaf litter .

Additional material studied. Three juveniles (1 extracted for DNA; MCZ) in 96% EtOH from Center for Environmental Development and Recreation ( CEDAR), Impalutao, Impasug-ong, Bukidnon Province, Mindanao I., Philippines, 775 m alt. (8.254933° N, 125.035749° E), leg. D. Mohagan, V. Yamba, R. M. Clouse, 30 June 2014, from sifted leaf litter .

Etymology. The specific epithet honors the invertebrate physiologist Geoffrey Fowler Dilly.

Diagnosis. Medium-sized (ca. 3.6 mm) Cyphophthalmi presenting a character combination diagnostic for Miopsalis : distinct eyes, anal gland pore and Rambla’s organ present, distinct sternum, extensive sculpturing on second cheliceral article, nearly parallel ventral opisthosomal sulci, nearly straight posterior margin of gonostome, and coxae II and IV each with distinct meeting points in males. Male also with distinct solea on tarsus I; presence of digiti of the gonopore complex; and arrangement of five ventral microtrichia of spermatopositor, with one proximal microtrichium on ventral midline and four subdistal microtrichia arranged in an arc. Distinguished from congeners by unique combination of medium size, and presence of anal gland pore, eyes, Rambla’s organ, prominent second ventral cheliceral process, and claw-like chelicerae. For example, M. mulu ( Shear, 1993) and M. sabah ( Shear, 1993) are also medium-sized and have anal gland pores, but they have attenuate chelicerae and no Rambla’s organ; M. gryllospeca ( Shear, 1993) has a small Rambla’s organ, claw-like chelicerae, and a large second ventral cheliceral process, but lacks an anal gland pore and is considerably larger (> 5 mm) (see table 1 and figure 19 in Clouse 2012 for further comparison).

Description. Length of holotype (female paratype in parentheses) 3.64 (3.59); maximum body width 1.93 (1.84) at third opisthosomal segment; length/width ratio 1.88 (1.95). Distance between ozopores, 1.67 (1.61) ( Fig. 1 )

Body oval, dark orange-coloured to reddish brown (in alcohol) depending on incidence of light ( Fig. 1 ). Body almost entirely with a dense tuberculate-microgranulate surface microstructure. Distinct eye lenses anterior to Type I ozophores ( Juberthie 1970; see also Giribet 2003) ( Fig. 1C, F ). Mid-dorsal, longitudinal opisthosomal sulcus absent (male; Fig. 1A ) or poorly defined (female; Fig. 1D ). Posterior end of body evenly rounded. Coxae of leg II fused to coxae of legs III and IV ( Fig. 2A, 2B ). Sternum present ( Fig. 2A, 2B ). Proximal end of coxae I or III of males not meeting along the midline (in females, only coxae II meeting in midline; Fig. 2A, B ). Male gonostome semicircular to trapezoidal, with weakly concave posterior edge, without cuticular projections ( Fig. 2A ). Spiracles C-shaped ( Fig. 2A, B ). Sternal opisthosomal glands absent. Sternites 8 and 9 and tergite IX free. Tergite IX of male distinctly bilobed. Anal plate of male with indistinct, raised, medial, longitudinal area lacking granulation, with shallow medial groove posteriorly ( Fig. 2C, D ). Anal gland pore present in male ( Fig. 2C ).

Chelicerae ( Fig. 3A ) not of the protruding type ( Giribet 2003) and claw-like (Clouse 2012), distal article/median article ratio 0.32 (0.31); widest part of median cheliceral article near the base and with ornamentation concentrated proximally; proximal article with dorsal crest and two distinct ventral processes. Palpal trochanter without ventral process ( Fig. 3B ). Legs with all metatarsi and tarsi ornamented; claws of all legs smooth ( Fig. 3 C–K). Tarsus I with a distinct solea ( Fig. 3D, J ). Rambla’s organ of male small, oval in shape, in distal portion of tarsus IV adjacent to tarsal claw ( Fig. 3I ). Adenostyle conspicuous, subtriangular, robust, fringing at the tip; located in proximal half of tarsus ( Fig. 3I ). Appendage measurements provided in Tables 1–2.

Spermatopositor ( Fig. 4 ), examined in three male paratypes, in dorsal view with eight long microtrichia on each side, their bases separated at midline. Dorsal microtrichia without serration ( Fig. 4A ). Ventral side with small denticles and five microtrichia, i.e. one proximal microtrichium on the ventral midline and four subdistal microtrichia arranged in an arc ( Fig. 4B ). Gonopore complex with a pair of long and gracile digiti ( Fig. 4C ).

Variation. Range of measurements of males (n=4) and females (n=6, in parentheses): Body length 3.48–3.79 (3.59–3.85), maximum width 1.82–1.96 (1.84–1.94).

Distribution. Known only from the two localities provided.

Figures

FIGURE 1. Miopsalis dillyi sp. nov. (A) Habitus of male holotype, dorsal view. (B) Same, ventral view. (C) Same, lateral view. (D) Habitus of female paratype, doral view. (E) Same, ventral view. (F) Same, lateral view. Scale bars as indicated.

FIGURE 2. Miopsalis dilly sp. nov. (A) Male paratype, ventral view of prosomal complex. (B) Female paratype, same. (C) Male paratype, ventral view of posterior part of opisthosoma. (D) Female paratype, same. Scale bars: 500 µm.

FIGURE 3. Miopsalis dilly sp. nov., details of limbs in retrolateral view. (A) Left chelicera of male paratype. (B) Right palp of male paratype. (C) Left leg I of male paratype. (D) Tarsus I of male paratype. (E) Right leg II of male paratype. (F) Left leg III of male paratype. (G) Right leg IV of male paratype. (H) Left leg IV of female paratype. (I) Tarsus IV of male paratype. (J) Tarsus I of female paratype (tarsal claw damaged during preparation). (K) Tarsus IV of female paratype. Scale bars: 500 µm.

FIGURE 4. Miopsalis dilly sp. nov. (A) Spermatopositor, dorsal view. (B) Same, ventral view. (C) Detail of the gonopore complex. Scale bars as indicated.