Acrotritia hauseri ( Mahunka, 1991 )

Liu, Dong & Chen, Jun, 2015, Acrotritia species (Acari: Oribatida: Euphthiracaridae) from China with description of a new species, Zootaxa 3937 (1), pp. 127-146 : 136-138

Acrotritia hauseri ( Mahunka, 1991)

( Figs. 4 A–H)

Measurements. Prodorsum: length 248–270, width 179–195, height 94–108, setae: ss 60–72, ro 50–54, in 105–112, le 60–65, ex 5–6, mutual distance: in–in 80, le–le 45, ro–ro 35; notogaster: length 452–560, width 310–410, height 312–402; c 1 65–68, c 2 60–64, c 3 60–64, c p 60–65, d 1 60–65, d 2 50–52, e 1 62 –65, e 2 49 –52, h 1 64–69, h 2 60–63, h 3 60–62, ps 1 60–64, ps 2 55–57, ps 3 50–54, mutual distance: c 1– d 1 110, d 1– e 1 140, e 1– h 1 82, h 1– ps 1 85; genito-aggenital plate 152×70, ano-adanal plate 215×59.

Colour yellowish to brown; prodorsum abruptly humped near insertion level of rostral setae in lateral view; one pair of long and strong lateral carinae present; sensilla with flat and truncate head, covered with small spines distally; prodorsal setae robust, rigid and barbed in distal half, except exobothridial setae; notogastral setae fairly short, similar in shape to lamellar setae; vestigial setae f 1 situated ventrad to setae h 1; 9 pairs of minute genital setae present, including 1 pair of setae inserted on progenital area; 2 pairs of aggenital setae located longitudinally; tarsi of legs I bidactylous, tarsi II–IV heterotridactylous.

Material examined. China: Hainan Province: 1 adult (in alcohol, LD-07-54), Dongfang, Datian, Polu, 70 m a.s.l., from litter under arbor, 5 Aug. 2007, leg. Dong Liu; 9 adults (in alcohol, LD-07-53), same data as LD-07-54; 1 adult (in alcohol, LD-07-55), from litter under dead wood, other data same as LD-07-54; 1 adult (in alcohol, LD- 07-56), from soil under shrub, other data same as LD-07-54; 1 adult (in alcohol, LD-07-57), from soil under Sophora japonica , other data same as LD-07-54; 1 adult (in alcohol, LD-07-64), Jianfengling, Institute of Tropical Forestry, 64 m a.s.l., from soil under arbor, 7 Aug. 2007, leg. Dong Liu; 4 adults (in alcohol, LD-07-65), from litter under Tectona grandis, other data same as LD-07-64; 10 adults (in alcohol, LD-07-66), from litter under Cratoxylum cochinchinense , other data same as LD-07-64; 1 adult (in alcohol, LD-07-72), from sawdust and soil, 9 Aug. 2007, other data same as LD-07-64; 3 adults (in alcohol, LD-07-73), from litter under Araucaria bidwilli , other data same as LD-07-72. China: Jilin Province: 3 adults (in alcohol, Changbaishan-C-7), Changbai Mt., from leaves under shrub, 23 Jul. 1980, leg. Hui-Fu Wang and Yun-Qi Cui; 1 adult (in alcohol, Changbaishan-C-50), Changbai Mt., Beipo, 1215 m a.s.l., from litter under coniferous forest, 13 Jul. 1979, leg. Rong-Zu Zhang; 1 adult (in alcohol, W-86-1), Antu County, Baihe, Changbai Mt., 730 m a.s.l., from litter under mixed forest of conifer and broad-leaved trees, 22 Jul. 1986, leg. Yun-Qi Cui; 1 adult (in alcohol, W-86-9), 600 m a.s.l., 14 Aug. 1986, other data same as W-86-1; 2 adults (in alcohol, W-86-13), Antu County, Baihe, Changbai Mt., 650 m a.s.l., from rotten wood under broad-leaved forest, 5 Aug. 1986, leg. Yun-Qi Cui and Cen-Xuan Pan. China, Shanghai: 1 adult (in alcohol, L-0106), Hongqiao, from soil under Metasequoia glyptostroboides forest, 15 Oct. 1995, leg. Qing-Tian Li. China: Nanjing: 2 adults (in alcohol, Yao-24), from litter, 28 Nov. 1983, leg. Wen-Bing Yao; 1 adult (in alcohol, L- 0101), same data as Yao-24; 5 adults (in alcohol, W-91-4), Zhongshanling, from litter, 30 May 1991, leg. Fu-Sheng Huang; 7 adults (in alcohol, W-91-5), same data as W-91-4; 8 adults (in alcohol, L-06-20), Zhongshanling, from litter under bamboo, 28 May 2006, leg. Zheng Liu; 1 adult (in alcohol, L-06-29), Linggusi, from soil under sweetgum, 30 May 2006, leg. Zheng Liu; 1 adult (in alcohol, L-06-32), from litter, other data same as L-06-29; 2 adults (in alcohol, L-0099), Nanjing University, from litter, 12 Apr. 1990, leg. Yue-Ling Liang; 4 adults (in alcohol, L-0100), same data as in alcohol, L-0099; 1 adult (in alcohol, L-06-25), Nanjing Normal University, Xianling Campus, from soil under forest, 29 May 2006, leg. Zheng Liu; 9 adults (in alcohol, W-89-36), eastern suburbs, from leaves under Platanus orientalis and arbor near road, 8 May 1989, leg. Hui-Fu Wang; 5 adults (in alcohol, W- 89-38), eastern suburbs, from leaves under Bamboo forest, 11 May 1989, leg. Hui-Fu Wang; 4 adults (in alcohol, W-89-40), eastern suburbs, from shrub under Platanus orientalis, 12 May 1989, leg. Hui-Fu Wang; 21 adults (in alcohol, W-89-42), from leaves in tea plantation, other data same as W-89-40; 6 adults (in alcohol, W-89-44), from leaves under Cedrus deodara , other data same as W-89-40; 5 adults (in alcohol, W-89-45), from leaves, other data same as W-89-40; 5 adults (in alcohol, W-90-16), Zhongshanmen, from litter, 8 Mar. 1990, leg. Yue-Ling Liang. China: Zhejiang Province: 2 adults (in alcohol, W-92-7), Leqing, Yandang Mt., from litter, 7 Apr. 1992, leg. Fu- Sheng Huang. China: Anhui Province: 1 adult (in alcohol, L-0149), Qiyun Mt., from moss, 23 Oct. 1995, leg.

Qing-Hai Fan. China: Jiangxi Province: 1 adult (in alcohol, Yao-19), Nanchang, from litter, 27 Aug. 1983, leg. Wen-Bing Yao; 1 adult (in alcohol, W-92-11), Nanchang, from litter, 13 Apr. 1992, leg. Lian-Sheng Huang. China: Shandong Province: 18 adults (in alcohol, W-91-13), Qianfo Mt., from leaves under pine trees, Dec. 1991, leg. Yun-Qi Cui; 5 adults (in alcohol, W-91-14), Qianfo Mt., Dafotou, from leaves and litter, other data same as W-91- 13. China: Henan Province: 16 adults (in alcohol, W-90-109), Dengfeng, Zhongyuemiao, from leaves, 23 Dec. 1990, leg. Fu-Sheng Huang; 2 adults (in alcohol, L-0244), same data as W-90-109. China: Hubei Province: 1 adult (in alcohol, W-89-111), Xuan’en County, Xiaoguan, 1100M, from leaves, 6 Aug. 1989, leg. Yun-Qi Cui; 8 adults (in alcohol, Yao-12), Wuhan, from leaves, 1 Sep. 1981, leg. Wen-Bing Yao. (Newly recorded species from China)

Remarks. The genus Acrotritia is not easy to deal with from the standpoint of systematics as there are few reliable morphological features. After studying thousands of specimens of this group these years, we found out that the shape of prodorsum is a “good and stable” feature that can be applied in the taxonomy. From this view, we considered A. hauseri as a valid species (synonymized with A. ardua by Niedbała (2011)), because it can be distinguished from the latter by the prodorsum abruptly humped near insertion level of rostral setae.

Compared with holotype, the specimens from China only differ by the position of aggenital setae (close to anterior margin of genito-aggenital plates versus remote in holotype). In our opinion, this arrangement of aggenital setae is very unusual in this genus. Before rechecking the type specimen, this question can not be well solved. Here we tentatively identify these specimens as A. hauseri .

Figures

FIGURE 4. Acrotritia hauseri (Mahunka, 1991): A, lateral view of body (legs removed); B, prodorsum, dorsal view; C, sensillum, dorsal view; D, ventral plate; E – G, trochanter, femur, genu and tibia: E, leg I; F, leg II; G, leg III; H, femur, genu and tibia: leg IV. Scale bars: A – B, D – H = 100 µm; C = 50 µm.