Macrocheles dayaci Dwibadra and Takaku, 2014

Dwibadra, Dhian, Takaku, Gen, Ôhara, Masahiro & Ueda, Akira, 2014, Mites of the Family Macrochelidae (Acari: Gamasida) from Sungai Wain, East Kalimantan, Indonesia, Species Diversity 19 (1), pp. 43-57 : 48-50

Macrocheles dayaci Dwibadra and Takaku sp. nov.

( Fig. 1 )

Type series. Holotype ( MZB. Acar. 7559.2): female, Hutan Lindung Sungai Wain, Balikpapan , East Kalimantan, 20 December 2006, ex Catharsius dayacus, A. Ueda and D. Dwibadra leg . Paratypes: 1 female, data same as in holotype; Km 24: 2 females, 26 December 2006, ex residue in vial.

Description. Female. Length of dorsal shield 1035 (1020–1050), width at level of coxae II 627.5 (600–660) (n =4). Specimens reddish brown in color.

Dorsum ( Fig. 1A ). Dorsal shield broadly rounded posteriorly with procurved outline, surface of shield covered with strong punctations and reticulation; lateral margin of shield smooth; shield bearing 28 pairs of dorsal setae and 22 pairs of pores; seta j1 pilose distally; z1 simple; other setae pilose distally.

Venter ( Fig. 1B ). Sternal shield wider than long; length 178.8 (175–180), width at level of coxae II 207.5 (200–210) (n =4); shield with 3 pairs of simple setae and 2 pairs of pores; l. ang. and l. m. t. present; l.o.a. with faint punctation; two punctate l. arc. distinct; l. o. p. present as distinct line, with punctations, connected to l. m. t.; a. p. p. with strong and coarse punctations. Metasternal shields oval and free; each shield with 1 simple seta and anterior pore.

Width of epigynial shield 273.8 (270–275) (n =4); shield ornamented with punctations, with pair of simple setae on the posterior corner.

Ventrianal shield longer than wide, length 411.3 (400– 420), width 317.5 (295–340) (n =4); shield with strong, dimpled reticulation and punctations; 3 pairs of preanal setae, 1 pair of paranal setae, and 1 postanal seta present; postanal seta pilose, other setae simple; cribrum located posterior to postanal seta.

Gnathosoma ( Fig. 1C ). Well developed and sclerotized. Deutosternal groove with 6 rows of denticles, anteriormost row divided; 3 pairs of simple hypostomal setae and 1 pair of simple palpcoxal setae present. Epistome ( Fig. 1E ) with median process and pair of lateral elements; median process bifurcate distally, and lacking minute spicules; basal margin serrate. Fixed digit of chelicera ( Fig. 1D ) with simple dorsal seta, robust median tooth, small distal tooth, pilus dentilis, and terminal hook; movable digit with robust bidentate median tooth, small distal tooth, and terminal hook; length of fixed digit 220 (200–230) and movable digit 96.9 (95–100) (n =4).

Legs. Most leg segments with simple and pilose setae except for coxae I–IV; trochanter I–III and tarsus I with only simple setae. Leg chaetotaxy typical for this genus. Genu IV with 6 pilose setae. Leg length (excluding ambulacrum, n =4); leg I, 758.8 (720–830); leg II, 715.6 (647.5–765); leg III, 702.5 (660–760); leg IV, 1007.5 (945–1045).

Sacculus foemineus. Not observed.

Male and other stages. Unknown.

Etymology. The specific name is derived from the specific epithet of the phoretic host, the scarab beetle Catharsius dayacus .

Remarks. M. dayaci is a member of the glaber species group and is similar to M. witcoskyanus Walter and Krantz, 1986 ( Walter and Krantz 1986b) in the shape of dorsal setae and shield sternal ornamentation. However, M. dayaci is distinguishable from M. witcoskyanus by the following characters (corresponding conditions of M. witcoskyanus in parentheses): 1) j4 and j5 pilose distally (simple); 2) z5 and j 6 in some cases slightly pilose (simple); and 3) ventrianal shield not expanded, longer than wide (expanded laterally, wider than long).

Figures

Fig. 1. Macrocheles dayaci Dwibadra and Takaku, sp. nov., female, holotype (MZB. Acar. 7559.2). A, dorsal shield; B, ventral shield (paratype, MZB. Acar. 7560.2); C, ventral view of gnathosoma; D, chelicera; E, tectum (paratype, MZB. Acar. 7559.1). Scale bars: 200µm (A, B); 50µm (C–E).