Gonodactylopsis herdmani ( Tattersall, 1906 )

Ahyong, Shane T., 2022, Revision of the Indo-West Pacific Coral Reef Mantis Shrimp Genus, Gonodactylopsis Manning, 1969 (Crustacea: Stomatopoda: Gonodactylidae), Records of the Australian Museum 74 (2), pp. 41-57 : 43-45

Gonodactylopsis herdmani ( Tattersall, 1906)

Figs 1, 2

Gonodactylus herdmani Tattersall, 1906: 169–170 , pl. 1 figs 8–10.— Borradaile, 1907: 210.— Kemp, 1913: 4, 11, 146, 148, 171–173, 174, 176, 199, pl. 10 fig. 114, 114a.— Manning, 1969: 149.— Manning, 1995: 20.— Schram, 2010: 52.

Gonodactylus Herdmanni. — Hansen, 1926: 31.

Mesacturus herdmani .— Manning, 1967: 2.— Shanbhogue, 1975: 524, 539.— Manning & Serène, 1968: 114.

Gonodactylopsis herdmani .— Manning, 1969: 149, fig. 1.— Chhapgar & Sane, 1977: 32.— Erdmann & Manning, 1998: 621.— Ahyong & Harling, 2000: 635.— Schram & Müller, 2004: 45.

Type material. Lectotype: NHM 1906.10.27.1, female (TL 26 mm), Gulf of Mannar , Ceylon, coral reefs, coll. W. Herdman & J. Hornell, pre 1906 . Paralectotype: NHM 1906.10.27.2, 1 female (TL 28 mm), Gulf of Mannar , Ceylon, coral reefs, coll. W. Herdman & J. Hornell, pre 1906 .

Description. Eyes elongate; cornea subconical, reaching anteriorly slightly beyond antennular article 2. Ocular scales low, subtruncate.

Antennular peduncle length 0.5–0.6CL. Antennal protopod with fixed, laterally flattened mesiodorsal spine, short anteroventral tooth; antennal scale length 0.4CL.

Rostral plate slightly wider than long; median spine twice length of basal portion (medially), laterally compressed, with obtusely angular ventral keel; lateral spines divergent with arcuate margins.

Raptorial claw dactylus with proximal notch on outer margin; propodus with proximal movable spine, opposable margin sparsely pectinate proximally.

Mandibular palp 3-segmented. Maxillipeds 1–5 each with epipod.

Thoracic somites 6 and 7 lateral processes subequal, lower margins subtruncate. Thoracic somite 8 anterolateral margin rounded; sternal keel obsolete.

Abdominal somites 1–5 posterolateral angles unarmed. AWCLI 740–747. Abdominal somite 6 with submedian, intermediate and lateral bosses unarmed.

Telson wider than long; submedian, intermediate and lateral denticles absent; submedian and intermediate teeth stout, blunt; submedian teeth subparallel; intermediate teeth wider than long, extending posteriorly to about proximal one-third of submedian teeth; lateral tooth low, convex not projecting posteriorly. Median carina inflated, tumid, with blunt posterior spine; accessory median carina with 1 or 2 blunt spines; anterior submedian carina with 2 or 3 blunt lobes; submedian tooth with large blunt basal spine followed by 2 or 3 smaller conical spines or tubercles and cristae carina extending to end of tooth; anterior intermediate carina irregular, sometimes partially subdivided, upright; intermediate tooth with blunt basal tubercle (occasionally fused with anterior intermediate carina), flanked laterally by irregular, upright carina; knob absent; submedian and intermediate teeth without ventral carinae.

Uropodal protopod terminal spines with outer slightly longer than inner, each with prominent ventral carina, inner with dorsal carina; upper proximal surface smooth behind dorsal carina, without obtuse swelling; stout spine above exopod articulation. Exopod proximal article dorsal surface with sharp, sinuous longitudinal carina and short carina mesioproximally; outer margin with 10 or 11 movable spines, distalmost reaching distal one-third of distal article; inner margin smooth, glabrous; distal margin with small ventral spine. Exopod distal article with outer distal margin setose, inner margin smooth, glabrous; dorsal and ventral surfaces with inner one-third membranous, soft, wrinkled, clearly demarcated from chitinized outer portion; outer chitinized portion with sharp, curved carina dorsally, ventrally with interrupted longitudinal carina adjacent to margin of membranous portion. Endopod length 2.8–3.2× width, crescentic, articulation with protopod posterior to anterior end; outer margin strongly convex, setose along distal half, inner margin weakly, irregularly concave, glabrous; dorsally with sharp, sinuous carina adjacent to outer margin; dorsal and ventral surfaces with inner half membranous, soft, wrinkled, clearly demarcated from chitinized outer half.

Colouration. According to Kemp (1913: 172): “Living specimens are quite pale in colour with dull yellow marbling, darkest at the antero-lateral corners of the abdominal somites and tending to a more reddish tone on the sixth somite and telson. The ridges and tubercles of these last two segments are pure white. The propodus of the raptorial claw has a red-brown patch at the extreme distal end, and near the apex of each of the rostral spines, there is a transverse red band”. Measurements. Female (n = 2) TL 26–28 mm. Other measurements of lectotype: CL 6.2 mm, antennular peduncle length 3.5 mm, antennal scale length 2.3 mm, abdominal somite 5 width 4.6 mm.

Remarks. Gonodactylopsis herdmani is unique in the genus for lacking submedian denticles on the telson, having short, stout intermediate telson teeth, and possessing low, convex lateral telson teeth that do not project posteriorly. The species remains known only from the type material and specimens reported by Kemp (1913), collected from the pearl banks in the Gulf of Mannar, Sri Lanka.

The two specimens of G. herdmani examined agree well in most respects ( Fig. 2 ), differing in minor aspects of telson tubercle arrangement, the number of spines on the accessory median carina (1 or 2), the more prominent lateral telson tooth in the TL 26 mm specimen, and in the segmentation of the mandibular palp. Three mandibular palp articles are clearly demarcated in the TL 28 mm specimen whereas the two distal articles (articles 2 and 3) are indistinctly differentiated in the TL 26 mm specimen. Kemp (1913: 171) also reported a “rather indistinct” division between mandibular palp articles in his material of G. herdmani , but between the two proximal articles rather than the distal two as observed here; Kemp’s (1913) reference to the proximal palp articles is probably a lapsus given that the proximal article typically differentiates in advance of the distal articles in stomatopods. The TL 26 mm female (NHM 1906.10.27.1), being in more complete condition than the TL 28 mm specimen, is herein selected as the lectotype to fix the identity of the species.

Distribution. Central Indian Ocean, presently known only from the Gulf of Mannar, Sri Lanka.

Figures

Figure 2. Gonodactylopsis herdmani (Tattersall, 1906): A–K, lectotype female, TL 26 mm, Ceylon, NHM 1906.10.27.1; L, paralectotype female, TL 28 mm, Ceylon, NHM 1906.10.27.1. (A) anterior cephalothorax, dorsal view; (B) right eye, lateral view; (C) ocular scales; (D) rostral plate, lateral view; (E) right antenna, lateral view; (F) right raptorial claw, lateral view; (G) thoracic somites 6–8, right lateral view; (H) abdominal somite 5 and 6, telson and left uropod; (I) abdominal somites 5, 6 and telson, lateral view; (J) right uropod, ventral view; (K) telson, ventral view; (L) telson, dorsal view. Scale = 2.0 mm.