Heptacarpus geniculatus (Stimpson, 1860)

Xu, Peng & Li, Xin-Zheng, 2015, Report on the Hippolytidae Bate (sensu lato) from China seas, Zoological Systematics 40 (2), pp. 107-165 : 150-151

Heptacarpus geniculatus (Stimpson, 1860) ( Fig. 27 )

Hippolyte geniculata Stimpson, 1860: 103 ; Ortmann, 1890: 503 (in part), pl. 37, fig. 3; Doflein, 1902: 636 (in part). Type locality: Hakodate , Hokkaido.

Spirontocaris geniculate Rathbun, 1902: 45 (in part), fig. 19; Yokoya, 1930: 530; 1939: 270.

Spirontocaris alcimede De Man, 1906: 404 ; 1907: 416, pl. 32, figs 42–46.

Heptacarpus geniculatus Holthuis, 1947: 12 , 44; Liu, 1955: 38, pl. 14, figs 1, 2; Miyake et al., 1962: 123; Hayashi & Miyake, 1968: 132, fig. 5; Hayashi, 1979: 21 (in part); Hayashi, 1989: 23; Liu & Zhong, 1994: 559 (list); Chace, 1997: 44 (list); Yang & Kim, 2005: 12, fig. 1; Komai & Ivanov, 2008: 15, figs 10–13, 18, 19.

Material examined. MBM109807 , 6 ♀ (cl 4.38–5.01 mm), Lian Island , 1957-9-27, coll. Jie-Shan Xu ; MBM109808 , 4 ♂ (cl 4.13–4.96 mm), 5 ♀ (cl 5.20–6.19 mm), Liaoning, Changhai, Haiyang Island , 1956-9-27 ; MBM109809 , 1 ♀ (cl 6.81 mm), Shandong, Qingdao , 1952-12-11, coll. Lan Zhang ; MBM109811 , 5 ♂ (cl 3.92–5.01 mm), 7 ♀ (cl 4.04–4.91 mm), Shandong, Qingdao, Yumingzui , 1955-9-20, coll. Jie-Shan Xu ; MBM109812 , 10 ♂ (cl 3.85–5.75mm), 2 ovig. ♀ (cl 6.83, 7.45 mm), Liaoning, Dalian, Xiaoping Island , 1956-10-13 ; MBM109813 , 1 ♂ (cl 4.80 mm), 1 ovig. ♀ (cl 7.55 mm), Shandong, Qingdao, Guizhou Road , 1955-3-19, coll. Jie-Shan Xu ; MBM109814 , 4 ovig. ♀ (cl 5.22–5.93 mm), Shandong, Yantai, Qingshan , 1954-3-2 ; MBM109815 , 5 ovig. ♀ (cl 6.16–6.96 mm), Shandong, Qingdao, Qianhai , 1952-11-4 ; MBM109816 , 1 ovig. ♀ (cl 6.35 mm), Shandong, Qingdao, Guizhou Road , 1953-12-21 ; MBM109817 , 9 ovig. ♀ (cl 6.06–6.84 mm), Houhai , 1953-1-20 ; MBM109818 , 6 ♀ (cl 5.69–6.12 mm) ; MBM109819 , 6 ♂ (cl 3.53–5.39mm), 4 ♀ (cl 5.22–5.56 mm), Shandong, Qingdao, Yumingzui , 1957-9-27, coll. Jie-Shan Xu ; MBM109822 , 21 ♂ (cl 5.28–5.65 mm), 16 ♀ (cl 4.87–6.32 mm), Shandong, Yantai, Zhifu , 1934-5-18 ; MBM109824 , 5 ♂ (cl 5.12–6.73 mm), 4 ♀ (cl 6.14–7.25 mm), 1965-4-17, coll. Hui-Lian Chen ; MBM109828 , 7 ♂ (cl 6.57–6.94 mm), 32 ovig. ♀ (cl 6.51–7.33 mm), Shandong, Yantai , 1932-11-5 ; MBM109839 , 21 ♂ (cl 5.61–6.59 mm), 28♀ (cl 5.94–7.38 mm), Liaoning, Dalian, Xiaoping Island , 1950-11-2 ; MBM109843 , 1♂ (cl 4.36 mm), Shandong, Yantai, Fish Market , 1951-4-11 .

Description. Rostrum straight, directed forward, generally styliform, reaching distal margin of antennal scale, 1.1–1.5 of carapace length; dorsal margin armed with 4–6 teeth including proximal 1 or 2 on carapace, distal half of dorsal margin unarmed; ventral blade relatively shallow, deepest at proximal to midlength; ventral margin with 6–9 teeth; lateral carina blunt. Dorsal margin of carapace in lateral view straight; suborbital lobe rounded, constricted at base, falling short of distal tip of antennal tooth; pterygostomial angle unarmed or armed with tiny tooth.

© Zoological Systematics, 40 (2): 107–165

1 mm.

Abdomen strongly gibbous. Second somite with faint transverse groove on tergite. Dorsal surface of third tergite strongly elevated in posterior part; posterodorsal margin of tergite weakly produced. Pleurae of anterior four somites broadly rounded, fifth pleuron with moderately large posteroventral tooth; posterolateral margin of fifth pleuron slightly sinuous. Sixth somite about 1.8 times longer than fifth. Telson about 1.20 length of sixth somite, armed with 3–5 pairs of dorsolateral spines; posterior margin with 3 pairs of unequal spines.

Eye-stalk generally subpyriform; cornea slightly wider and shorter than remaining part of eyestalk; ocellus distinct, showing as black spot. Antennular peduncle falling short of midlength of antennal scale. First segment unarmed on dorsodistal margin; stylocerite overreaching distal margin of first segment, acuminate, mesial margin convexor sinuous, closely in touch with first segment; second segment about 1/3 length of first segment, with large spine at dorsolateral distal angle; third segment short, with moderately large spine on dorsodistal margin.

Antenna with basicerite bearing moderately large ventrolateral distal tooth; carpocerite reaching 1/3 length of antennal scale. Antennal scale 5.6 times longer than wide; lateral margin straight or slightly concave; distal lamella rounded, strongly produced, considerably exceeding beyond distolateral tooth.

Third maxilliped falling short of midlength of antennal scale; ultimate segment tapering distally, with seven darkly pigmented corneous spines distally. First pereopod moderately stout, slightly overreaching base of antennal scale; chela 1.5 of carpal length; dactylus about 0.6 length of palm; merus about 1.6 of carpal length. Second pereopods reaching midlength of antennal scale; dactylus about 0.6 of palm length; carpus about 3.80 times longer than chela, divided in 7 unequal articles; ischium subequal in length to merus. Third to fifth pereopods relatively short, similar in structure. Third pereopod overreaching midlength of antennal scale by length of dactylus; biunguiculate dactylus 1/3 of propodal length, armed with 5–6 accessory spinules on flexor margin; propodus with 2 rows of slender spinules on flexor margin; carpus about half of propodal length; merus armed with 6–8 spines ventrally. Fourth pereopod not reaching midlength of antennal scale; merus with 4–7 lateral spines. Fifth pereopod reaching 1/3 of antennal scale; propodus with tufts of grooming setae distally; merus with 3–5 lateral spines.

Endopod of first pleopod elongate subtriangular, with conspicuous appendix interna at terminal position; second pleopod with appendix masculina distinctly longer than appendix interna, with numerous long setae on dorsal surface to tip.

Coloration in life. Variable; body and appendages usually transparent, dark brown, reddish brown, or green. Occasionally with white middorsal longitudinal stripe.

Distribution. Northern China seas; temperate waters in East Asia, Japan and Korea; intertidal to 10 m. Abundant in Zostera belts of inshore waters.

Figures

Fig. 27. Heptacarpus geniculatus (Stimpson, 1860). A. Carapace, lateral view; B. Abdominal pleurae, lateral view. Scale bars=