Myrmarachne

Genus Myrmarachne described by Bohdanowicz and Proszynski, 1987

Systematic studies on East Palaearctic Salticidae (Araneae), IV. Salticidae of Japan

Genus Myrmarachne

Species Myrmarachne inermichelis Bosenberg et Strand, 1906

Myrmarachne inermichelis Bosenberg et Strand, 1906: 329-330, ff.128, 382 et auct.seq., Yaginuma 1970: 672, 1974: 109, ff.297.
Material. 1 male - Myrmarachne inermichelis Bos.et Strand -　Japan, Tado, Wakayama, 30.V.1951; 1 female - Myrmarachne inermichelis Bos. et Str.- Japan, Miyazaki, Kyushu[widely distributed in Japan and common], 14.VI.1953 - both samples leg.det.T.Yaginuma - coll.J.Proszynski.
(from Bohd. and Prosz.,1987)

Male.
Cephalothorax elongate, yellowish fawn, almost bald, rough. Eye surrounding light brown. Around eyes I some bent whitish bristles.
Legs I yellowish white, weak and elongate, with 2 pairs of weak spines on metatarsus, 3 on tibia and 1 spine on patella, other legs similar but spines weaker yet (and less numerous).
Abdomen elongate, fawnish yellow with lighter belt at two fifth of its length and posterior tip, lateral surfaces also lighter with grey longitudinal stripes posteriorly. Anal tubercle and spinnerets greyish yellow.
Clypeus narrow, yellowish fawn with whitish hairs. Chelicerae much elongate, string, directed forwards, fawnish yellow, with 11 (10 on left) retromarginal and 1 promarginal thorns, no twig on the fang. Palpal organ shown on figs.160-162.
Sternum elongate, narrow and deeply serrated at the legs base, yellow, bald.
Abdomen ventrally yellowish white.
(from Bohd. and Prosz.,1987)

Female.
Female dorsally similar to male.
Differences: cephalothorax fawnish brown, much more laterally and dorsally constricted in its half length, underlined ventrally by a pair of tufts of white adpressed setae, eyes surrondings black.
Legs I with 9 spines on tibia (5 in prolateral row), no spines on leg III and IV, all legs greyish yellow.
Abdomen dorsally constricted, underlined ventrally by tufts of light adpressed setae in its anterior (greyish yellow) part, posteriorly greyish brown; pigmentation continued laterally. Anal tubercle and spinnerets greyish brown.
Clypeus narrow, brown, with scarce whitish hairs. Chelicerae normal, with dense combs of 4 retromarginal and about 8 promarginal teeth ("fissidentati"). 【NOTICE！ Its description is wrong. Cheliceral normal, with dense combs of 4 promariginal and 8 retromarginal teeth. (IKEDA'S COMMENT.10, August, 2004) 】
Pedipalps yellowish fawn, spatular. Sternum yellow brown. Abdomen yellowish grey, laterally darker, anteriorly yellowish white. Epigyne shown on figs.163-166.

Measurements

♂	0.84	length of eye field		height	h=	height/L of　CT
	2.02	length of cephalothorax	0.95	width of eye field I (on level of eyes I)	a=0.41	L of EF/L of CT
	2.60	length of abdomen	1.01	width of eye field III (on level of eyes III)	b=0.94	W of eye I/W of eye III
	d=1.18　　(length of tibia IV:lenght of tibia III)				c=0.88	L of EF/W of EF eye I
♀	0.84	length of eye　field		height	h=
	2.07	length of cephalothorax	0.92	width of eye field I (on level of eyes I)	a=0.41
	2.71	length of abdomen	1.01	width of eye field III (on level of eyes III)	b=0.91
	d= 1.80　　(length of tibia IV:lenght of tibia III)				c=0.91

Length of segments of legs:

	leg	femur	patella	tibia	metatar.	tarsus	ALL
♂	I	0.36	0.56	0.95	0.50	1.20	3.07
	II	0.31	0.48	0.62	0.42	0.90	2.73
	III	0.34	0.70	0.62	0.42	0.73	2.81
	IV	0.36	0.92	0.73	0.48	1.18	3.67
♀	I	0.34	0.50	0.78	0.48	0.92	3.02
	II	0.28	0.42	0.56	0.39	0.76	2.41
	III	0.34	0.62	0.56	0.36	0.84	2.46
	IV	0.39	0.98	1.01	0.53	1.23	4.14

　　　　　　　　　　　　　　　　　 (from Bohd. and Prosz.,1987)

Species　Myrmarachne　japonica　（Karsch,1879）

The original description of Karsch's as follows. (1879. )

28. Salticus　japonicus　n. sp., male juv.
Leibeslange 8mm. Der hohe Kopftheil schwarts, der Thorax heller braun, auf ihrer Grenze jederseits ein feiner weisslicher Querstnich. Mandibeln, Palpen, Maxillen und Sternum schwarztlich; die Coxen I und II blass, bei einem der Exemplare mit schwarzen Basalfleckchen; die Schenkel schwarzlich, die ubrigen Glieder blass, seitlieh mit je einem schwarzen Langsstreif; Tarsus II ganz blass, Coxa III und IV achwarzbraun, die ubrigen Glieder schwarzlich, nur die Unterseito des Metatarsus III und die Tarsen III und IV blass. Hinterleib vor der Mitte sanft eingeschnurt, fast kahl, die Einschnurung seitlich mit weissem, querem schmalem Striche bezeichnet, welche uin der Mitte des Ruckens verwischt zusammenfliessen. Grundfarbe des Hinterleibes graubraun, schuppig glanzend, vor der Einschnurung seitlich, schwarzschattig, desgleichen ein oder mehrere schattig quere Bogenstriche hinter der Einschnurung und die Seiten Schwarz zum Bauche hin verloren, so dass daudurch ein vor den Spinnwarzen verschmalertes etwas dreikckiges hellbraungraues Feld des Bauches gebildet wird. Durch die Lange, namentlich des Beinpaares IV, kommt die Art den Charakteren der Gattung Toxeus C.Koch (=? Symenosyna Hentz) nahe. --- Hilgendorf. 　　　

Species Myrmarachne kuwagata Yaginum, 1967
Material. 1 male - Myrmarachne kuwagata Yaginuma, 1967, Japan, Haguro-cho, Yamagata Pref.[occurs in limited areas of Honshu and Shikoku, rare],7.VI.1952, leg.S.Okitsu, det.T.Yaginuma - coll.J.Proszynski.

Male.
Cephalothorax more rectangular in outline than in male of Myrmarachne inermichelis, fawnish brown, with scarce whitish bristles (over eyes I longer and medially bent) except in the central part of eye field.
Eyes surroundings blackish. Eye field with golden metalic gleam and protuberance as in Myrmarachne inermichelis. Ventral margin of carapace bordered greyish brown.
Leg I greyish yellow with spines on ventral surfaces: 2 pairs on metatarsus, 4 pairs on tibia, 1 spine on patella; other legs similar, spines on leg II less numerous, no spines on legs III and IV.
Abdomen blackish brown with short transparent setae. Anal tubercle and spinnerets yellowish grey, retraced.
Clypeus narrow, brown, with long whitish bristles. Chelicerae shown on figs.168-169, on right 9+3 retromarginal and 2 promarginal teeth.
Palpal organ shown on figs.167-171. Sternum as in female of Myrmarachne inermichelis. Abdomen and its lateral surfaces blackish brown, broad lighter median stripe.
　　　　　　　　 (from Bohd. and Prosz.,1987, 98)

Measurements

♂	0.92	length of eye field		height	h=	height/L of CT
	2.60	length of cephalothorax	1.04	width of eye field I (on level of eyes I)	a=0.35	L of EF/L of CT
	2.44	length of abdomen	1.12	width of eye field III (on level of eyes III)	b=0.93	W of eye I/W of eye III
	d=1.72　　(length of tibia IV:lenght of tibia III)				c=0.88	L of EF/W of EF eye I

Length of segments of legs:

	leg	femur	patella	tibia	metatar.	tarsus	ALL
♂	I	0.48	0.92	1.54	1.79	1.62	6.35
	II	0.36	0.73	1.01	0.70	1.20	4.00
	III	0.50	0.95	1.04	0.67	1.29	4.45
	IV	0.67	1.60	1.79	0.84	2.04	6.94.

Species Myrmarachne magna S.SAITO, 1933 (from Saburo SAITO,1933.

Notes on the Spiders from Formosa. Nat. Hist. Soc., 13:32-60+pl.3)

The original description of S.SAITO is as follows.
10. Mrrmarachne magnus n.sp. Jap. Name, Oo-arigumo Pl.III, Fig. 27 a-g.

Male. cephalothorax deep blackish brown, covered with fine, white hairs, and a few long, fine prominent ones at the caput; narrow and elongate in shape, divided into two well-marked parts by a deep transverse constriction.
Eye space forma a quadrangle, whose length and breadth are equal; eyes differing greatly in size arranged in three rows; four anterior eyes almost in contact with each other and the central eyes the largest of the eight with a diameter twice that of the laterals which is the same as that of the one in the third row; the eyes of the second row being smallest, situated closer to the anterior row than to the third row.
Legs deep blackish brown; coxae, trochanters, patellae and the ends of tibiae of the first legs, the tibiae metatarsi, tarsi of the second and third legs and the trochanters of the fourth legs dull brown; the fist leg furbished with six strong spines.
Palpus short, deep brown with thick, black hairs; its structure simple, possessing a process at the termination of tibia. Maxillae long, strong, narrowest just above the insertion of the palpi, much broader at the top, black in colour.
Sternum dull brown.
Chelicerae deep brown, strong, long and the inner-side furnished with the eight teeth.
Abdomen deep blackish brown, densely covered with fine white hairs.
The measurement are as follows (in centimeters) :-- total length, 1.00; Cephalothorax, 0.40; abdomenm 0.30; chelicerae, 0.40; leg I, 1.20, leg II, 0.80, Leg III, 0.80, leg IV, 1.10. Locality: Taihoku (R.TAKAHASHI), October 24, 1927. Remarks: This species differs from the other species of Myrmarachne in having six spines on the tibia of the first leg and especially in the great body length.
(IKEDA's Comments; The SAITO's figures of this species are sufficient for the identification.)

Figures;　See　http://salticidae.org/salticid/main.htm

IKEDA's Comments; The description of the species M.gigantea as follows.

Species. Myrmarachne gigantea ZABKA, 1985.
(from MAREK ZABKA, 1985. Systematic and zoologeographic study on the family Salticidae (Araneae) from Viet-Nam. Ann. Zoologici, 39(11):197-485.)

The original description of ZABKA is as follows.

Myrmarachne gigantea sp.n.
Material; 1 male holotype - Thanh Ha , prov. Hoa Binh, 14 VI 1966, 1 female allotype, 1 male paratype - Cue Phuong. Prov. Ninh Binh, tropical rain forest, calcareous rocks, 9 VI 1966, BP, IZPAN. 1 male paratype - Cue Phuong, prov. Ninh Binh, beaten from bushes in the forest, 6 V 1966, T, HNHM.

Male(holotype). Cephalothorax tall, with a median constriction, dark orange. Eye field slightly darker, surroundings of eyes black-brown. Anterior part with fine grey setae, posteriorly and near eyes tufts of white setae.
Length of cephalothorax 3.10, length of eye field 1.20, width of eye field I 2.15, width of eye field III 1.95.
Abdomen oval, with vast brown-grey scutum with an indistinct margin. Surface of scutum coverd with fine grey setae.
Length of abdomen 3.05. Spinnerets grey. Clypeus dark orange with numerous yellow-grey hairs.
Chelicerae (Fig.322) dark orange, thick long, with characteristic large teeth near the base of the claw. On both edges there are also smaller teeth. Maxillae and labium grey-orange, sternum yellow, venter grey, towards lateral surfaces lighter longitudinal streaks.
Palpal organ (Figs.318-321) big, with an oval bulbus and embolus forming a double loop. Tibial apophysis slightly hooked laterally. On the lateral surface long dense bristles, two short spines in the distal part of cymbium.
Legs very long and delicate. Leg I grey-orange, other turning grey. All covered with small sparse hairs and light brown spines.

Female (allotype) (Fig.325). Cephalothorax with a strong median constriction, slender, brown, surroundings of eyes darker. On the whole surface white and grey hairs.
Length of cephalothorax 3.01, length of eye field 1.01, width of eye field I 1.25, width of eye field III 1.35.
Abdomen without a scutum, grey, in the median part a broad lighter belt. Anteriorly two small apodemes. On the whole surface light grey spots. Length of abdomen 3.10. Spinnerets yellowish grey. Pedicel (Fig.326) of a characteristic shape. Clypeus light brown with grey and brown hairs.
Chelicerae (Fig.327) thick, orange brown. Pedipalps brown, maxillae and labium exceptionally long, light brown with orange apices. Sternum light orange, venter medially light grey, towards lateral surfaces darker with longitudinal light streaks.
Epigyne (Figs.323, 324) with a pocket in the median part. Internal structures simple. In their proximal part membraneous, barely visible canals, in the distal part accessory glands.
Three proximal segments of legs I white grey. Legs II shorter, coxae and trochanters grey-brown, femora white-grey, distally darker. Other segments yellow-orange, laterally darker. Leg III grey-brown, distal part of metatarsus and tarsus yellow-orange. Trochanters and proximal parts of patellae of legs IV white-grey, remaining part grey-brown.
Specimens of both sexes similar in body form and coloration.
The structure of copulatory organs indicates a relationship between the species and representatives of groups "formicaria" and "volatilis" (WANLESS, 1978a). M.gigantean has however its own complex of distinguishing characters: big body size and characteristic body form, strong and thick chelicerae, palps of males with a brush of dense bristles and two spines at the apical part of ctmbium, structure of pedicel in females, simple in structure, much elongated internal canals of epigyne.

Figures;　See　http://salticidae.org/salticid/main.htm

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