Philippipalpus agohoi Corpuz-Raros, 1978

Beard, Jennifer J., Seeman, Owen D. & Bauchan, Gary R., 2014, Tenuipalpidae (Acari: Trombidiformes) from Casuarinaceae (Fagales), Zootaxa 3778 (1), pp. 1-157 : 112-115

Philippipalpus agohoi Corpuz-Raros, 1978

( Figs 95–97 )

Philippipalpus agohoi Corpuz-Raros, 1978: 220 , fig. 5.

Philippipalpus agohoi Smiley et al. (1996) : 172, figs 11–15.

Type material examined. 5 female paratypes ex. Coastal She-Oak (“Agoho”) Casuarina equisetifolia (Casuarinaceae) , THE PHILIPPINES, Cagayan, Sta. Ana, 31 March 1977, coll. J.M. Sotto ( USNM, 2 slides).

Diagnosis. Distance between setae v2 -h1 300–310. Distance between e2-e2 130–140. Prodorsal shield with oblique depressions, covered with fine reticulate sculpturing. Cuticle between prodorsal and opisthosomal shields (sejugal region) strongly papillate-striate. Opisthosomal shield with 4–5 pairs of broad transverse depressions with finely reticulate cuticle within each depression sublaterally; 4–5 smooth ridges in sublateral cuticle associated with depressions; mesonotal region indistinctly separated from pygidial region. Lateral cuticle with> 100 strong papillae. Cuticle between 3a-4a with mixed striae. Vesicle of spermatheca round, 2 x 2, with granulate appearance.

FEMALE (5 paratypes). Dorsum. ( Fig. 95 a) Body measurements: distance between setae v2 -h1 300–310, sc2- sc2 115–125; other measurements: v2-v 2 25–38, sc1-sc1 88–95, c1-c1 35–42, c3-c3 150–165, d1-d 1 26–29, d3-d3 135–150, e1- e 1 16–23, e2-e2 130–140, e3-e3 115–120, f3-f3 90–98, h1-h 1 21–28, h2-h2 58–67. Gnathosoma completely concealed beneath the prodorsum. Anterior margin of the prodorsum with deep medial notch (internal depth 15–19), forming 1 pair of broad fleshy lobes; setae v2 inserted beneath a fold on the lobes; anterior notch located within a weak depression ( Fig. 95 a). Prodorsal shield with fine reticulation of small cells; 4–5 pairs of oblique depressions and associated oblique ridges on lateral margin of shield medad setae sc1–2; laterad cuticle strongly papillate. Three pairs of tiny pores present sublaterally, in longitudinal row. Cuticle between prodorsal and opisthosomal shield (sejugal region) obviously papillate. Opisthosomal shield with smooth to folded and papillate sculpturing medially between c1–e1; 4–5 pairs of broad transverse depressions with finely reticulate cuticle within each depression sublaterally; 4–5 pairs of smooth transverse ridges in sublateral cuticle between the depressions; lateral cuticle strongly papillate; posterior cuticle between e1–h1 finely striate to reticulate. Paired tiny pores between each of c1–c3, d1–d3, and 2 pairs sublateral to e1; 1 pair of large pores present medad d3–e3 (total 5 pairs of pores visible). All dorsal setae barbed, thick, with triangular cross-section (except e1, h1). Setal lengths: v 2 17– 20, sc 1 18–22, sc 2 21–23, c 1 19–24, c 3 18–23, d 1 13–18, d 3 21–22, e 1 12 –15, e 2 21 –24, e 3 21 –24, f 3 20–23, h 1 14–16, h 2 19–22. Palps. ( Fig. 95 b) Setal formula 0, 0, 0, 2, 3(1s+2e). Tibial setae, dorsal 7–8 long, ventral 9–11 long; tarsal eupathidia 5–7 long, 7–8 long; solenidion 6–7 long. Venter. ( Fig. 96 a) Cuticle anterolaterad 1a with granular appearance; cuticle between 1b -1a with longitudinal striae; 1a -3a with transverse striae; striae mixed between 3a -3a; 3a -4a with transverse to wavy striae; 4a -4a with mixed striae becoming transverse posterior to 4a, then longitudinal around the genital region. Genital setae inserted in more-or-less transverse line along posterior margin of genital shield, setae g1 inserted slightly posterior to g2. Genital shield membranous, weakly developed, smooth. All coxal setae fine. Setal lengths: 1a 52–78, 1 b 20–28, 2 b 18–22, 2 c 21–23, 3 a 48–74, 3 b 22–31, 4 a 44– 53, 4 b 26–29, ag 1 15–19, g 1 21–25, g 2 18–21, ps 1 14–17, ps 2 13–17, ps 3 9–12. Spermatheca. ( Fig. 96 b) Spermathecal tube long and narrow, 100–105 long, ending in a granular, membranous vesicle. Genital opening anteromedad anal setae ps3. Legs. ( Fig. 97 ) Setal formula for legs I–IV (coxae to tarsi) 1-0-3-1-4-8(1), 2-0-3-1-4- 8(1), 1-1-2-0-2-4, 1-0-1-0-2-4. Tarsi I and II each with 1 antiaxial solenidion ω" (10–11 long) and 2 eupathidia pζ'- pζ" (7–8, 8–9 long). Leg setation as in Table 1 except: coxae I without 1c; tr I–IV without v ′ (l' present on tr III); ge I–II with d, ge I–IV without l ′, ge I–II without l′′; ti III–IV without d; ta I–IV without tc ′′.

OTHER STAGES. Unknown.

Remarks. The redescription of Smiley et al. (1996) reported two setae on genu I, but there is only one dorsal seta present on this segment. Also, they reported the setal count on tarsi I–II as 6(1), but the count is actually 8(1). Philippipalpus agohoi and P. flumaquercus are similar in that they both have strongly papillate dorsolateral cuticle, and can be separated from P. nigraquercus and P. belah that both have smooth to weakly papillate dorslateral cuticle. Philippipalpus agohoi can be separated from P. flumaquercus by having a finely reticulate prodorsum, while the latter has a coarsely rugose prodorsum.

The host genus, Casuarina , is the most widespread genus in the family, and Ca. equisetifolia is the most widely distributed species within the genus, with a littoral distribution ranging across tropical and subtropical coastlines of northern and northeastern Australia, Burma to Vietnam, Malesia, Melanesia and Polynesia ( Johnson & Wilson 1989). This plant has also been introduced to the southern United States, West Africa and Madagascar ( Johnson & Wilson 1989). The wide present day distribution of Ca. equisetifolia is an example of the ability of Casuarinaceae species to achieve dispersal by wind and sea (and highly likely by humans) ( Steane et al. 2003). In a phylogenetic study by Steane et al. (2003), two subspecies of Ca. equisetifolia , subsp. equisetifolia and subsp. incana, collected from Queensland, Australia, grouped with Casuarina species from the Indomalesian region, rather than with other Australian endemic species. Such a grouping suggests that Ca. equisetifolia is either a relatively new species that came to Australia from Indomalesia, or it evolved in Australia (from an ancestor shared with the other Indomalesian taxa) and then dispersed to other regions ( Steane et al. 2003). The origin of this species is of great interest in terms of the origin of Ph. agohoi which is the only non-Australian species in the Tegopalpinae. Records of Ca. equisetifolia from India, the Mascarene Islands (near Madagascar) and other tropical areas are regarded as relatively recent deliberate or accidental introductions ( Johnson & Wilson 1989).

Figures

FIGURE 95. Philippipalpus agohoi Corpuz-Raros, adult female, a. dorsum; b. detail of palp (scale bar for palp = 25 Μm).

FIGURE 96. Philippipalpus agohoi Corpuz-Raros, adult female, a. posterior venter; b. spermatheca.

FIGURE 97. Philippipalpus agohoi Corpuz-Raros, adult female, legs (right side), eupathidia (pζ ′ - pζ ′′) not labelled on leg I.