Myrmeleon littoralis Miller and Stange, 1999

Lin, Yu-Hsiu, Liao, Jhih-Rong & Ko, Chiun-Cheng, 2021, Fig. 5 in Periclimenaeus karantina Park & De Grave 2021, sp. nov., Zoological Studies 60 (39), pp. 1-24 : 13-15

Myrmeleon littoralis Miller and Stange, 1999 ( Figs. 3E , 4E , 10 )

Despite this species is included in the key to antlion larvae of Taiwan by Stange et al. (2003), the larvae of this species is described here for the first time.

Description of 3rd instar larva: Size: Average body length 9.15 mm (7.79–10.93); head length 1.92 mm (1.75–2.22), head width 1.63 mm (1.60–1.71), mandible length 1.95 mm (1.76–2.24), ratio head width/ length 0.85, ratio mandible length/head length 1.02.

General coloring: Pale ochre, slightly reddish, with dark brown body markings.

Head: Sub-rectangular, longer than wide. Densely covered with short, black setae. Ocular tubercle sessile. Mandibles pale brown with apex reddish, as long as the head capsule, provided with 3 equidistant teeth with the apical tooth slightly stronger. Interdental mandibular setae: (6–10)(2–4)(2–3)(1). Clypeo-labrum with pointed setae. External margin of the mandible with a fringe of long setae, dorsal side of the mandible with a sparse covering of short setae on the margins, ventral side of the mandible with a sparse covering of setae external to the maxilla, reaching the basal tooth, and few isolated setae disposed internal to the maxilla. Labial palpus 4-articulated, with fringe of black setae underneath, few extending over labial palpus. Dorsal side of the head with a dark spot on clypeo-labrum, a pair of dark spots on the anterior side of head capsule with a small pale brown spot in between, posterior side with V-shaped dark markings. Lateral side of the head with two large dark markings, one close to the dorsal side and the other on the ventral-posterior side, occasionally fused together. Ventral side of the head with a pair of triangular dark brown spots on the posterior side.

Thorax: Pronotum with a pair of pale brown stripes, covered with short setae. Body setae black.

Legs: Pale brown, unspotted.

Abdomen: Setae black, with pale brown setae on the ventral side. VIII abdominal sternite with a pair of dark brown spots, odontoid processes distinct, posterior margin with hair-like setae. IX abdominal sternite with a median row of 4 peg-like digging setae. Rastra sessile, each bearing 3 peg-like digging setae, of which the external one is the longest, 1 seta on the external side.

Materials examined: Taiwan. Hsinchu County. Hengshan St. Wood Factory, Hengshan Township / 26. XI. 2019 / J. W. Chuang leg., 2 L3 laboratory reared to adult. Kaohsiung City. Qijing Beach, Qijing District / 16. XI. 2019 / Y. H. Lin leg., 6 L3 laboratory reared to adult. Kinmen County. Liaoluo Seashore Park, Jinhu Township / 04. IX. 2020 / Y. H. Lin leg., 2 L2, 2 L3. Miaoli County. Qiding Seaside Park, Zhunan Township / 08. XI. 2019 / Y. H. Lin leg., 1 L3 laboratory reared to adult. Shangrila Paradise Amusement Park, Zaoqiao Township / 23. IX. 2017 / Y. J. Tsao leg., 1 L2 laboratory reared to adult; same locality / 12. I. 2018 / Y. J. Tsao leg., 1 L2 laboratory reared to adult, 1 L3 laboratory reared to adult; same locality / 03. III. 2018 / Y. J. Tsao leg., 1 L2 laboratory reared to adult, 1 L3 laboratory reared to adult; same locality / 05. V. 2018 / Y. J. Tsao leg., 1 L3 laboratory reared to adult; same locality / 09. VI. 2018 / Y. J. Tsao leg., 1 L3 laboratory reared to adult; same locality / 07. VII. 2018 / Y. J. Tsao leg., 1 L3 laboratory reared to adult; same locality / 04. VIII. 2018 / Y. J. Tsao leg., 1 L3 laboratory reared to adult; same locality / 01. IX. 2018 / Y. J. Tsao leg., 1 L3 laboratory reared to adult; same locality / 06. X. 2018 / Y. J. Tsao leg., 1 L2 laboratory reared to adult, 1 L3; same locality / 04. XI. 2018 / Y. J. Tsao leg., 2 L2 laboratory reared to adult, 1 L3, 2 L3 laboratory reared to adult; same locality / 01. XII. 2018 / Y. J. Tsao leg., 1 L2, 1 L2 laboratory reared to adult, 1 L3, 7 L3 laboratory reared to adult; same locality / 12. I. 2019 / Y. J. Tsao leg., 1 L3, 3 L3 laboratory reared to adult; same locality / 06. VII. 2019 / Y. J. Tsao leg., 1 L3; same locality / 17. VIII. 2019 / Y. J. Tsao leg., 1 L3 laboratory reared to adult. Tongxiao Beach, Tongxiao Township / 04. V. 2020 / Y. H. Lin leg., 1 L3. New Taipei City. Fulong Seaside Park, Gongliao District / 07. VI. 2019 / Y. H. Lin leg., 1 L3, 2 L3 laboratory reared to adult. Laomei, Shimeng District / 04. VIII. 2019 / Y. H. Lin leg., 4 L3, 2 L3 laboratory reared to adult. Laoqiankeng Road, Bali District / 30. X. 2019 / Y. H. Lin leg., 1 L3, 3 L3 laboratory reared to adult; same locality / 20. IV. 2020 / Y. H. Lin leg., 2 L3. Linkou Canyon, Linkou District / 08. XI. 2019 / Y. H. Lin leg., 1 L3 laboratory reared to adult; same locality / 07. XI. 2020 / Y. H. Lin leg., 4 L3. Longmeng Bridge, Gongliao District / 15. XII. 2019 / Y. H. Lin leg., 2 L3, 1 L3 laboratory reared to adult. Longmeng Camping Ground, Gongliao District / 15. XII. 2019 / Y. H. Lin leg., 2 L3 laboratory reared to adult. Shalun Seaside Resort, Tamsui District / 04. VII. 2018 / Y. H. Lin leg., 1 L3 laboratory reared to adult; same locality / 01. VI. 2019 / Y. J. Tsao leg., 3 L2 laboratory reared to adult, 3 L3 laboratory reared to adult; same locality / 03. IX. 2019 / Y. H. Lin leg., 1 L2, 1 L3, 5 L3 laboratory reared to adult. Wazihwei Beach, Bali District / 11. IX. 2019 / Y. H. Lin leg., 2 L3 laboratory reared to adult. Penghu County. Aimen Beach, Huxi Township / 16. I. 2020 / Y. H. Lin leg., 6 L3, 4 L3 laboratory reared to adult. Houliao Beach, Baisha Township / 13. I. 2020 / Y. H. Lin leg., 2 L3 laboratory reared to adult. Lintou Park, Huxi Township / 13. I. 2020 / Y. H. Lin leg., 2 L3. Shanshui Beach, Magong City / 16. I. 2020 / Y. H. Lin leg., 2 L3 laboratory reared to adult. Pingtung County. Gangkou Beach, Manzhou Township / 03. II. 2020 / Y. H. Lin leg., 1 L3. Houbihu Beach, Hengchun Township / 04. II. 2020 / Y. H. Lin leg., 1 L3, 1 L3 laboratory reared to adult. South Bay, Hengchun Township / 03. II. 2020 / Y. H. Lin leg., 1 L3, 1 L3 laboratory reared to adult. Taichung City. Dakeng Trail No. 4, Beitun District / 24. VI. 2020 / Y. H. Lin leg., 2 L3 laboratory reared to adult. Taoyuan City. Caota Sand Dunes, Guanyin District / 08. XI. 2019 / Y. H. Lin leg., 1 L3 laboratory reared to adult. Yongan Seaside Park, Xinwu District / 08. XI. 2019 / Y. H. Lin leg., 1 L3, 3 L3 laboratory reared to adult.

Bio-ecology: M. littoralis can be observed from coastal wind-break to low-elevation forests. The larvae build their pits in sheltered conditions, wherever a suitable loose substratum is present, at base of trees, near escarpments, under rock overhangs or under artificial structures such as buildings and bridges, it was even found in a wood factory, where the larvae build pitfalls in sawdust. The larvae of M. littoralis may co-habitat with those of M. bimaculatus , M. taiwanensis and M. punctinervis . The larvae of this species are able to move both forward and backward.

Distribution: Endemic to Taiwan. This species is found along the western coast and the inland areas, also in the surrounding islands— Penghu and Kinmen.

Remarks: One of the most common species in Taiwan. The larvae can be identified by the head markings.

Figures

Fig. 3. Head of 3rd instar larvae of Myrmeleontini of Taiwan, ventral view; A, Baliga asakurae; B, Myrmeleon alticolus; C, Myrmeleon bimaculatus; D, Myrmeleon heppneri; E, Myrmeleon littoralis; F, Myrmeleon persimilis; G, Myrmeleon punctinervis; H, Myrmeleon taiwanensis; I, Myrmeleon wangi. Scale bar = 1 mm.

Fig. 4. IX abdominal sternite of 3rd instar larvae of Myrmeleontini of Taiwan, ventral view; A, Baliga asakurae; B, Myrmeleon alticolus; C, Myrmeleon bimaculatus; D, Myrmeleon heppneri; E, Myrmeleon littoralis; F, Myrmeleon persimilis; G, Myrmeleon punctinervis; H, Myrmeleon taiwanensis; I, Myrmeleon wangi. Scale bar = 1 mm.

Fig. 10. Myrmeleon littoralis Miller and Stange, 1999, 3rd instar larva.A, dorsal view; B, ventral view; C, lateral view.