The genus Erythraeus (Acari: Erythraeidae) from China with descriptions of two new species and a key to larval species of the genus worldwide Author Xu, Si-Yuan Author Yi, Tian-Ci Author Guo, Jian-Jun Author Jin, Dao-Chao text Zootaxa 2019 2019-07-26 4647 1 54 82 journal article 25595 10.11646/zootaxa.4647.1.7 65f216f4-26f1-4a26-8656-1463b9fcaf01 1175-5326 3353363 E110C814-7D90-4E82-A2CA-CABE420F33E8 Erythraeus ( Erythraeus ) hubeiensis sp. nov. ( Figs. 1–11 ) Diagnosis (larva). fnBFe = 2-2-2; Ta I 176–180; Ti I 289–306; Ta III 161–176; Ti III 393–415; fD 35–38. Description (n = 10; holotype , 9 paratypes ). Dorsum. Idiosoma with 37 (fD = 35–38 in paratypes ) barbed setae and with blunted ends. Two pairs of eyes without platelets placed on each side ( Fig. 1 ). Scutum sub-rounded or oval, wider than long, anterior margin straight, posterior margin slightly convex. Scutum with two pairs of normal setae (AL and PL) and two pairs of trichobothria (ASE and PSE), scutalae barbed and with pointed ends, AL ˃ PL, PW ˃ AW ( Table 1 ). Two pairs of trichobothria (ASE and PSE) with minute barbs in distal half. ASE slightly behind AL bases, PSE bases far from bases of PL and close to posterior edge of scutum ( Figs. 1 , 3 ). TABLE 1 . Measurements of Erythraeus ( Erythraeus ) hubeiensis sp. nov. (larvae, a–j = paratypes )

character	Holotype	a	b	c	d	e	f	h	i	j	SD	range
fD	37	36	36	36	38	35	36	36	37	36	0.8	35–38
fV	16	16	16	16	16	18	16	16	16	16	0.9	16–18
IL	494	821	528	694	373	709	397	395	740	404	160.9	373–821
IW	391	750	514	581	282	650	358	302	681	350	162.4	282–750
DS	66–78	63–81	63–77	57–74	59–77	66–79	61–77	68–84	62–76	60–74	2.2–3.3	57–68
PDS	71–78	72–81	69–77	69–74	66–77	70–79	68–77	73–84	70–76	67–74	2.1–2.2	66–84
Oc’	21	21	17	19	18	21	17	18	18	19	1.5	17–21
Oc’’	17	16	13	14	15	18	15	14	13	14	1.6	13–18
1a	74	73	73	69	73	70	74	69	71	72	1.8	69–74
1b	111	106	106	102	96	96	99	94	100	99	5.1	96–111
2b	43	34	32	34	30	30	31	30	32	31	3.7	30–43
3a	51	49	51	46	47	50	51	48	51	52	1.9	46–52
3b	47	45	44	42	41	42	44	42	43	47	2.0	41–47
L	103	100	94	97	90	93	95	91	105	98	4.7	90–105
W	121	117	120	118	119	121	112	117	123	122	3.0	112–123
AW	55	47	47	48	50	53	47	51	53	50	2.7	47–55
PW	94	92	91	95	93	94	87	86	96	93	3.1	86–96
MA	22	19	20	20	19	21	18	20	22	18	1.4	18–22
AA	15	11	13	13	15	14	12	13	14	13	1.2	11–15
SB	16	14	14	16	16	15	14	14	15	14	0.9	14–16
ISD	73	73	68	71	65	70	70	64	72	66	3.1	64–73
AP	48	50	47	51	46	47	45	46	47	49	1.8	45–51
AL	103	98	101	/	94	/	96	91	97	100	3.6	91–103
PL	91	90	88	/	83	/	86	77	/	89	4.5	77–91
ASE	56	53	59	/	49	/	51	53	55	51	3.0	49–59
PSE	88	79	80	/	76	/	77	82	74	82	4.1	74–88
PaScFed	54	59	59	54	56	53	49	47	51	49	3.9	47–59

...Continued on the next page TABLE 1. (Continued)

character	Holotype	a	b	c	d	e	f	h	i	j	SD	range
PaScGed	63	63	66	61	62	61	64	60	65	62	1.8	60–66
GL	129	128	124	130	127	128	123	123	130	121	3.1	121–130
cs	21	24	25	21	23	22	23	20	23	24	1.5	20–25
as	11	13	12	11	15	9	11	12	12	13	1.5	9–15
bs	39	42	37	41	42	38	45	39	40	42	2.2	37–45
TaI (H)	19	20	20	18	19	19	16	20	18	17	1.3	16–20
TaI (L)	177	179	177	178	176	180	178	178	178	176	1.2	176–180
TiI	298	303	299	293	289	306	289	304	293	304	6.1	289–306
GeI	203	202	196	195	187	201	187	200	196	206	6.1	187–206
TFeI	151	149	145	147	143	146	147	142	137	145	3.7	137–151
BFeI	136	143	138	130	131	133	140	144	133	142	4.9	130–144
TrI	68	66	64	57	56	58	54	61	66	55	4.9	54–68
CxI	83	77	76	72	81	87	77	70	85	77	5.2	70–87
TaII (H)	17	16	19	17	17	18	17	18	19	16	1.0	16–19
TaII (L)	167	154	152	154	153	163	162	157	157	159	4.7	152–167
TiII	285	294	289	273	283	282	279	289	282	287	5.6	273–294
GeII	166	164	143	147	154	160	152	150	156	161	7.1	143–166
TFeII	125	123	128	127	120	123	119	120	119	125	3.1	119–128
BFeII	134	130	124	130	123	127	134	128	138	130	4.4	123–138
TrII	62	59	66	67	57	64	56	63	58	56	3.9	56–67
CxII	94	86	91	95	90	93	81	88	84	94	4.5	81–95
TaIII (H)	14	15	16	13	14	15	16	13	16	14	1.1	13–16
TaIII (L)	173	170	163	166	162	161	176	172	169	176	5.3	161–176
TiIII	411	407	399	408	393	400	397	407	394	415	7.1	393–415
GeIII	202	196	183	186	189	201	185	187	184	199	7.1	183–202
TFeIII	164	162	159	163	157	154	157	153	153	159	3.8	153–164
BFeIII	147	145	142	145	144	141	148	142	144	147	2.2	141–148
TrIII	63	69	60	58	57	64	53	60	57	52	4.9	52–69
CxIII	92	101	102	86	94	104	87	88	97	92	6.1	86–104
LegI	1116	1119	1095	1072	1063	1111	1072	1099	1088	1105	18.7	1072–1119
LegII	1033	1010	993	993	980	1012	983	995	994	1012	15.2	983–1033
LegIII	1252	1250	1208	1212	1196	1225	1203	1209	1198	1240	20.1	1196–1252
IP	3401	3379	3296	3277	3239	3348	3258	3303	3280	3357	51.5	3239–3401

Venter. All ventral setae including coxalae with pointed tips. One pair of nude sternalae 1a , one pair of barbed sternalae 3a , 1a ˃ 3a in length ( Table 1 ) and eight pairs of barbed setae behind coxae III (fV = 16–18). Coxal setae barbed, coxalae 1b longer than 2b and 3b , and 3b slightly longer than 2b ( Fig. 2 , Table 1 ). NDV = 52–54. Gnathosoma with one pair of nude galealae ( cs ), two pairs of nude hypostomalae ( as and bs ) ( Fig. 4 ); bs (37–45) much longer than as (9–15), hypostomal lip fimbriate. Dorsum of palpfemur and palpgenu each with one barbed and pointed setae, palptibia with one nude seta and one barbed seta on venter, one barbed seta on dorsum, odontus bifid ( Fig. 4 ). Palptarsus with eight setae including two barbed setae, four nude setae, one solenidion (ω), one eu- pathidium (ζ), and one Cp ( Figs. 4, 5 ), fPp = 0-B-B-BBN 2 -BBNNNNωζCp ( Fig. 5 ). Palpal supracoxal seta ( elcp ) peg like. FIGURE 1. Erythraeus ( Erythraeus ) hubeiensis sp. nov. , larva. Dorsal view of idiosoma. FIGURE 2. Erythraeus ( Erythraeus ) hubeiensis sp. nov. , larva. Ventral view of idiosoma. FIGURE 3–5. Erythraeus ( Erythraeus ) hubeiensis sp. nov. , larva. 3—scutum, 4—ventral view of gnathosoma, 5—ventral view of palp tarsus. Leg ( Figs. 6–11 ) with seven segments (femora divided). IP = 3239–3401 ( Holotype and nine paratypes ). Pedal basifemur I with one nude and pointed tip seta ( Fig. 6 ), other setae on legs barbed and pointed. Leg setae formula: Leg I: Cx—1n; Tr—1n; BFe—2n (B, N); TFe—5n; Ge—1σ, 1κ, 8n; Ti—2φ, 1κ, 1Cp, 14n; Ta—1ω, 1ε, 2ζ, 26n. Leg II: Cx—1n; Tr—1n; BFe—2n; TFe—5n; Ge—1κ, 8n; Ti—2φ, 15n; Ta—1ω, 2ζ, 23n. Leg III: Cx—1n; Tr—1n; BFe—2n; TFe—5n; Ge—8n; Ti—1φ, 15n; Ta—1ζ, 24n. Etymology . The name of the new species is derived from the province where it was collected. Type material . Holotype : larva ex nymph of unidentified species in Typhlocybini ( Cicadellidae : Typhlocybinae ), mite parasitic on head, collector SI-YUAN XU, 11 August 2015 , Qizimeishan National Natural Reserve , Hubei Province , China . Paratypes : 5 larvae ex plants, one larva ex unidentified species of Aphididae , mite attached to pronotum, same data as the holotype ; 3 larvae ex nymph of unidentified species in Typhlocybini , mites parasit- izing head, mesothorax and end of abdomen, collector SI-YUAN XU, 17 August 2015 , Huaping Township, Jianshi County , Hubei Province , China . The holotype and all paratypes are deposited in the Institute of Entomology, Guizhou University, China ( GUGC ) ( Zhang 2018 ). Remarks. Erythraeus ( Erythraeus ) hubeiensis sp. nov. belongs to the species groups with fn Bfe 2-2-2 (2-2-1) ( Šundić et al . 2015a , b; Stålstedt et al . 2016). This group includes 10 species: E . ( E .) phalangoides (De Geer, 1778) ; E . ( E .) tinnae Haitlinger, 1997 ; E. ( E .) chinensis ( Zheng, 2002 ); E . ( E .) picaforticus Haitlinger, 2002 ; E . ( E .) kacperi Haitlinger, 2004 ; E . ( E .) yangshuonicus Haitlinger, 2006; E . ( E .) etnaensis Haitlinger, 2011; E . ( E .) walii Kamran, Afzal, Raza, Bashir & Ahmad, 2011 ; E . ( E .) serbicus Šundić, Haitlinger & Hakimitabar, 2015; E . ( E .) aphidivorous Šundić, Haitlinger, Michaud & Colares, 2015 . Erythraeus ( Erythraeus ) hubeiensis sp. nov. differs from E. ( E. ) phalangoides in having sternalae 1a nude (vs. barbed), and by a number of measured characters given in Table 4. FIGURES 6–7. Erythraeus ( Erythraeus ) hubeiensis sp. nov. , larva. 6—leg I, trochanter–genu, 7— leg I, tibia–tarsus. FIGURES 8–9. Erythraeus ( Erythraeus ) hubeiensis sp. nov. , larva. 8—leg II, trochanter–genu, 9—leg II, tibia–tarsus. FIGURES 10–11. Erythraeus ( Erythraeus ) hubeiensis sp. nov. , larva. 10—leg III, trochanter–genu, 11—leg III, tibia–tarsus. E. ( E .) hubeiensis sp. nov. differs from E. ( E .) tinnae in having sensillary setae of scutum nude (vs. barbed in the latter). The new species is also different from the latter as follows: basifemur I has two setae, of which one is nude and another one barbed (vs. two barbed setae); lesser number of setae in fD formula (35–38 vs. 47). Other dif- ferences are in Table 4. E. ( E .) hubeiensis sp. nov. differs from E. ( E .) chinensis as follows: eyes are without platelets (vs. with platelets), apices of 2b and 3b are pointed (vs. blunt); two pairs of hypostomal setae are present (vs. one pair); BFe I has one nude seta (vs. two barbed setae), and the greater number of setae are in fV formula (16–18 vs. 12). E. ( E .) hubeiensis sp. nov. differs from E. ( E .) picaforticus as follows: scutum is sub-rounded or oval (vs. hexagonal), BFe I has one nude seta (vs. two barbed setae). The new species differ from E. ( E .) picaforticus by lesser number of setae in fD formula (35–38 vs. 72). Other differences are Table 4. E. ( E .) hubeiensis sp. nov. differs from E. ( E .) kacperi in having BFe I with one nude seta (vs. two barbed setae); the greater number of setae in fD formula (35–38 vs. 29) and in fV (16–18 vs. 8); the presence of solenidion on Ge I (vs. absent). Other differences are in Table 4. E. ( E .) hubeiensis sp. nov. differs from E. ( E .) yangshuonicus in having BFe I with one nude seta (vs. two barbed setae); eyes without platelets (vs. with platelets). The new species differs also from E. ( E .) yangshounicus by lesser number of setae in fD formula (35–38 vs. 56). Other differences are Table 4. E. ( E .) hubeiensis sp. nov. differs from E. ( E .) etnaensis in having Ge I and Ge II with microsetae (vs. absent) and Ti I with companion seta (vs. absent). The new species also differs from E. ( E .) etnaensis in having BFe I with one nude seta (vs. two barbed setae); and lesser number of setae in fD formula (35–38 vs. 64). E. ( E .) hubeiensis sp. nov. differs from E. ( E .) walii as follows: one nude seta on BFe I is present (vs. absent), solenidion on Ge II is absent (vs. present). Other differences are Table 4. E. ( E .) hubeiensis sp. nov. differs from E. ( E .) serbicus by Ta II without famulus (vs. with famulus); lesser dorsal setae (35–38 vs. 70–71). Other differences are in Table 4. E. ( E .) hubeiensis sp. nov. differs from E. ( E .) aphidivorous as follows: eyes are without platelets (vs. with platelets), 2b and 3a have pointed apices (vs. bifid at apices) and BFe I has one nude seta (vs. two barbed setae). Other differences are in Table 4 .