Myrmica yadori

Myrmica yadori
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Myrmicini
Genus:	Myrmica
Species group:	lobicornis
Species complex:	lobicornis
Species:	M. yadori
Binomial name
	Myrmica yadori; Terayama, Kinomura & Kitazawa, 2024

Common Name

Yadori-kushikeari
Language:	Japanese

This species is a workerless inquiline of Myrmica jessensis.

At a Glance

• Workerless Inquiline

Photo Gallery

Terayama et al. (2024), Figs. 21–24. Body rubbing behavior by the Myrmica yadori gyne (21, 22) and pupae and emerged gynes of Myrmica yadori (24). 21, Two M. yadori gynes (arrows) approach the M. yessensis gyne, one M. yadori gyne from the front and other from the back; 22, The gyne of M. yadori hung over the M. jessensis gyne, gripping the petiolar area of M. jessensis gyne by her legs, and pointing toward the gaster of the gyne; 23, The body size of the M. yadori gyne (arrow) is similar to that of M. jessensis worker; 24, Pupae and emerged gynes of M. yadori (alate individuals).

Identification

Terayama et al. (2024) - In female and male, this species is easily separable from the other East Asian congeners by the high and short petiole and postpetiole, with the distinct ventral lobes, and the absence of middle tibial spure. The male has 12 segmented antennae, although Myrmica males have usually 13-segmented antennae.

Keys including this Species

Key to Japanese Myrmica workers

Distribution

This species is currently only known from the type locality in Yamanashi Prefecture on Honshu, Japan.

Terayama et al. (2024), Fig. 1. Map showing the sampling location and distribution of Myrmica surusumi (circles) and Myrmica yadori (square).

Latitudinal Distribution Pattern

Latitudinal Range: 35.8° to 35.8°.


North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

Source: Terayama et al., 2024

Distribution based on Regional Taxon Lists

Japan (type locality).

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Biology

Castes

A workerless inquiline.

Male


Male. Photographer Terayama et al. (2024).	Owned by NIAS.

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

yadori. Myrmica yadori Terayama et al., 2024: 79, figs. 1, 9, 10, 15-20 (q.m.) JAPAN.
- Type-material: holotype gyne, 10 paratype gynes, 4 paratype males
- Type-locality: holotype Japan: Yamanashi-ken, Hakuto-shi, Hakushu-cho, v-vi. 2023 (R. Kitazawa); reared
- Type-depository: NIAS (holotype + paratypes)

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Type Material

Holotype worker: Japan, Yamanashi-ken, Hakuto-shi, Hakushu-cho, May-June 2023 (R. Kitazawa) (deposited in NIAS).
Paratypes: 8 paratype queens, 2 paratype males with same data as holotype; 2 paratype queens, 2 paratype males with same data as holotype but 23 July 2021 (all deposited in NIAS).

Description

Gyne

Measurements (mm) and indices: Holotype gyne; HL 0.91, HW 0.80, FW 0.30, FLW 0.38, SL 0.68, AL 1.40, HTL 0.74, PL 0.40, PW 0.30, PH 0.53, PPL 0.35, PPW 0.45, PPH 0.55, PSL 0.15, PSD 0.33, SCW 0.78, MCL 1.08, AH 0.93, TL 3.8, CI 0.88, FI 0.38, FLI 1.25, SI1 0.74, SI2 0.84, PI1 1.36, PI2 0.76, PI3 0.37, PPI1 0.64, PPI2 1.22, PPI3 1.53, PPI4 0.56, PSLI 0.19, PSWLDI 2.17, AI 1.51, SCI 1.39.

Measurements (mm) and indices: Paratype gynes (n=7); HL 0.90±0.07, 0.83–0.98, HW 0.79±0.05, 0.71–0.85, FW 0.30±0.01, 0.28–0.31, FLW 0.37±0.01, 0.35–0.38, SL 0.67±0.03, 0.63–0.70, AL 1.38±0.08, 1.25–1.48, HTL 0.69±0.04, 0.63–0.73, PL 0.38±0.02, 0.35–0.40, PW 0.29±0.01, 0.28–0.30, PH 0.52±0.01, 0.50–0.53, PPL 0.34±0.02, 0.33–0.38, PPW 0.46±0.01, 0.45–0.46, PPH 0.55±0.01, 0.53–0.56, PSL 0.15±0.01, 0.13–0.16, PSD 0.33±0.01, 0.33–0.35, SCW 0.72±0.03, 0.68–0.73, MCL 1.04±0.06, 0.95–1.10, AH 0.86±0.09, 0.78–0.95, TL 3.8±0.1, 3.6–4.0, CI 0.89±0.03, 0.85–0.91, FI 0.38±0.02, 0.35–0.40, FLI 1.23±0.03, 1.17–1.27, SI1 0.74±0.02, 0.72–0.76, SI2 0.84±0.02, 0.82–0.88, PI1 1.28±0.07, 1.17–1.33, PI2 0.74±0.03, 0.70–0.77, PI3 0.37±0.03, 0.35–0.42, PPI1 0.63±0.03, 0.52–0.68, PPI2 1.20±0.02, 1.17–1.22, PPI3 1.56±0.05, 1.50–1.64, PPI4 0.58±0.03, 0.54–0.63, PSLI 0.19±0.01, 0.17–0.21, PSWLDI 2.32±0.14, 2.18–2.54, AI 1.60±0.01, 1.52–1.83, SCI 1.44±0.08, 1.34–1.54.

Structure: With characters diagnostic of the genus Myrmica and as mentioned above. Head 1.14 times as long as wide, with weakly convex posterior margin, gently convex sides, and round occipital corner in full-face view. Mandible with 7 tooth; apical two larger. Anterior margin of clypeus with a notch medially; anteriodorsal margin moderately convex in lateral view. Antennae with 12 segments; first 5 antennomeres in a ratio of 64 : 12 : 7 : 6 : 6 in length; scape shorter than head length (SI1 0.74), and head width (SI2 0.84); base of scape strongly angled, bent at a right-angle with an acute triangle corner and straight anterior margin in lateral view; in anterior view, basal surface rectangular with vertical and dorsal lobes; pedicel 2.4 times as long as wide; 3rd segment slightly longer than wide; 4th to 8th segments each as long as wide; apical 4 segments forming a club; terminal segment 1.9 times as long as wide. Frontal lobe convex, frontal carina strongly concave, merging with ruga that extend to occipital margin; frons narrow (FI 0.38). Compound eye prominent, 0.23 mm in maximum diameter, with ca. 15 facets in the longest row. Ocelli forming an obtuse triangle, anterior ocellus ca. 0.05 mm in diameter. Dorsal outline of alitrunk almost straight in profile; in dorsal view anterolateral corner rounded, not forming a distinct angle. Mesoscutum 1.07 times as long as wide in dorsal view; axilla + scutellum as long as wide, with convex posterior margin. Propodeal dorsum straight in profile; propodeal spine short and blunt (PSL 0.15 mm), 1.2 times as long as its basal width, with weakly convex dorsal margin and blunt tip. Petiole higher than long (PI2 0.76), with almost straight anterior margin, convex dorsal margin; anterodorsal and posterodorsal margins both not forming angle; ventral lobe well developed, with an anterior projection; in dorsal view, petiole longer than wide (PI1 1.36), dorsal disc rectangular, wider than long, with almost straight lateral margins. Postpetiole higher than long (PPI1 0.64), with convex dorsal margin; ventral lobe developed, with convex ventral margin; in dorsal view, postpetiole wide (PPI3 1.53), trapezoidal, widest at near posterior margin, with convex lateral margins and almost straight posterior margin. Middle and hind legs without tibial spur. Gaster oval, 1.19 time as long as wide, 1.35 mm in maximum width in dorsal view.

Sclupture: Surface between frontal carinae with ca. 16 longitudinal rugae; vertex rugose, with microreticulate interspaces; gena and malar space rugose, with microreticulate interspaces; temple reticulate. Mandible with many longitudinal striae from the base to tip. Clypeus with 7 longitudinal rugulae at median portion. Pronotum and mesoscutum rugose, with microreticulate interspaces; axilla and scutellum longitudinal rugose and smooth interspaces; lateral surface of pronotum with longitudinal rugae; anepisternum microreticulate, with 7 longitudinal rugae; katepisternum weakly microreticulate, with about 7 longitudinal rugae; propodeum with longitudinal rugose lateral surface, rugulose dorsal surface, and smooth declivitous surface. Lateral surfaces of petiole and postpetiole with rugulose and microreticulate upper half and smooth lower half. Gaster smooth and shining. Legs mostly smooth. Erect or suberect golden setae abundant at head, pronotal dorsum, dorsa of petole and postpetiole, and gastrial terga; erect or suberect setae on head ca. 0.08–0.13 mm long and suberect setae on 1st gastral tergite ca. 0.18–0.20 mm long.

Color: Body yellowish brown excepting frons, vertex, dorsum of alitrunk darker; gaster brown; mandible and antenna yellowish brown; legs yellowish brown.

Male

Measurements (mm) and indices: Paratype males (n=4); HL 0.83±0.05, 0.78–0.89, HW 0.75±0.03, 0.73–0.80, FW 0.34±0.02, 0.33–0.38, FLW 0.25±0.01, 0.25–0.26, SL 0.59±0.01, 0.58–0.60, AL 1.36±0.09, 1.28–1.50, HTL 0.78±0.06, 0.73–0.88, PL 0.33±0.01, 0.33–0.34, PW 0.27±0.01, 0.26–0.28, PH 0.48±0.02, 0.46–0.51, PPL 0.29±0.01, 0.28–0.30, PPW 0.43±0.02, 0.40–0.45, PPH 0.48±0.02, 0.48–0.51, PSL 0.09±0.03, 0.05–0.11, PSD 0.33±0.02, 0.33–0.36, SCW 0.77±0.03, 0.73–0.80, MCL 0.99±0.07, 0.88–1.05, AH 0.88±0.04, 0.88–0.93, TL 3.8±0.3, 3.6–4.2, CI 0.91±0.03, 0.87–0.94, FI 0.46±0.01, 0.45–0.47, FLI 0.74±0.03, 0.70–0.77, SI1 0.71±0.02, 0.68–0.74, SI2 0.78±0.02, 0.75–0.79, PI1 1.23±0.01, 1.21–1.24, PI2 0.68±0.02, 0.66–0.70, PI3 0.35±0.01, 0.34–0.36, PPI1 0.35±0.01, 0.34–0.36, PPI2 1.14±0.03, 1.12–1.19, PPI3 1.60±0.05, 1.52–1.64, PPI4 0.57±0.02, 0.53–0.59, PSLI 0.12±0.03, 0.07–0.15, PSWLDI 3.98±1.21, 2.89–6.00, AI 1.54±0.05, 1.49–1.62, SCI 1.29±0.03, 1.21–1.35.

Structure: Head longer than wide excluding eyes, 1.07–1.18 times as long as wide, with convex posterior margin and round posterolateral corners in full-face view. Mandible with 6–7 teeth; anterior 2 teeth larger. Anterior margin of clypeus with a notch medially. Antenna with 12 segments; first 5 antennomeres in a ratio of 24 : 4 : 4.5 : 3 : 3 in length; scape shorter than head width (SI2 0.75–0.79); bent at obtuse angle with a rounded corner, without lateral lobe; pedicel ca. 1.3 times as long as wide; 3rd segment 1.6 times as long as wide, 4th and 5th each as long as wide; apical 3 segments forming a club; terminal segment ca. 2.4 times as long as wide. Frons relatively wide (FI 0.45–0.47); frontal carina straight, distance between carinae widest at posterior end. Compound eye strongly prominent, 0.33–0.35 mm in maximum diameter. Ocelli forming obtuse triangle, anterior ocellus ca. 0.04 mm in diameter. Mesoscutum with broadly convex dorsal margin in profile; scutellum thick and raised, with almost convex dorsum. Propodeal dorsum very weakly convex; declivitous surface concave; propodeal spine triangular, shorter than its basal width, varies in length (PSL 0.11–0.05 mm). Petiole short and high (PI2 0.66–0.70), with very weakly convex dorsum, its posterior slope steeper than anterior slope, anterolateral and posterolateral margins forming obutuse angle; ventral lobe well-developed, with an anterior projection; in dorsal view, petiole longer than wide (PI1 1.21–1.24), dorsal disc rectangular, wider than long, with straight lateral margins. Postpetiole higher than long (PPI1 0.54–0.63), with convex dorsal margin; ventral lobe developed, with narrowly convex ventral margin; in dorsal view, postpetiole wide (PPI3 1.52–1.64), with convex anterior margin and almost straight lateral and posterior margins. Middle leg without tibial spur, hind leg with a simple, not pectinated tibial spur which is ca 0.15 mm long. Gaster 1.00–1.05 mm in maximum width in dorsal view.

Sclupture: Frons microreticulate with about 10 rather irregularly rugae and several rugulae; vertex rugose, with microreticulate interspaces; malar space to temple reticulate, with microreticulate interspaces. Pronotum microreticulate, upper portion with weak rugulae; mesoscutum with reticulate rugose; axilla and scutellum reticulate; propodeal dorsum microreticulate, with weakly reticulate; anepisternum microreticulate, with several longitudinal rugulae; katepisternum and lateral surface of propodeum longitudinally rugose, with weakly microreticulate interspaces. Lateral surfaces of petiole with rugose and microreticulate upper half and smooth under; postpetiole smooth. Gaster smooth and shining. Legs weakly microreticulate. Erect or suberect golden setae abundant at head, alitrunk, dorsa of petole and postpetiole, and gastric terga; erect or suberect setae on head ca. 0.08–0.12 mm long and suberect setae on 1st gastral tergite ca. 0.08–0.13 mm long. Suberect setae on antennal scape long, 0.9 times as scape width, and ca. 0.10 mm long.

Color: Head brown; alitrunk petiole, postpetiole and gaster yellowish brown excepting dorsum of alitrunk and propodeal spine brown; mandible brown excepting masticatory margin blackish brown; antennal scape brown, pedicel and funicles brown to yellowish brown; legs yellowish brown.

Etymology

The specific epithet is the Japanese noun Yadori, which means parasite, referring to the social parasitism in this species.

References

Terayama, M., Kinomura, K., Kitazawa, R. 2024. Two New Species of the Ant Genus Myrmica Latreille, 1804 (Hymenoptera: Formicidae: Myrmicinae) from Japan. Japanese Journal of Systematic Entomology 30 (1):74-85.