Leptestheria gomantaki, Padhye & Kulkarni & Pagni & Rabet, 2023

Padhye, Sameer M., Kulkarni, Mihir R., Pagni, Marco & Rabet, Nicolas, 2023, New leptestherid clam shrimps (Pancrustacea: Branchiopoda: Spinicaudata Leptestheriidae) from peninsular India, Zootaxa 5264 (2), pp. 205-220 : 210-212

Leptestheria gomantaki sp. nov.

( Figs. 5 , 6B , 7B )

Leptestheria sp. M089 ( Schwentner et al. 2020)

Etymology. The species is named after the Indian name for the Goa region, Gomantak.

Type locality. A dried temporary pool in sand dunes in Benaulim , India: Goa (15°15′36″N, 73°55′13″E; Date of collection of sediment Oct 2016). The absence of typical aquatic vegetation suggests that water is only present for a short time .

Type material. Holotype. One female (without carapace) (in 4% formalin + glycerin) deposited at the Western Regional Centre of Zoological Survey of India ( ZSI), Pune (Registration number: ZSI-WRC C.2074)

Other material estudied. One female.

Description. Male. Males were not obtained in the rehydrated sediments.

Description. Female (holotype).

Head. Eyes large, noticeable ocular tubercle but ocular notch not very conspicuous, ocellus elongated with a crescent shape, projecting fornix, rostrum triangular, spine present at the tip of rostrum, spine ~5 times as long as wide and arched, occipital condyle projecting but not prolonged with a pointed apex directed perpendicularly to the dorsal margin, L/W ratio of ~0.6. ( Fig. 5A ).

First antenna. Bulbous and prolonged, more than two times the length of base of second antenna, about 6–8 lobes present on dorsal margin, each lobe lined with several sensillae.

Second antenna. Bi-ramous with 14 flagellomeres, each flagellomere bearing about 3–8 long posteriorly projecting spines with acute apices on posterior surface and plumose setae on the anterior face.

Carapace. Length. 6.3 mm; Width 3.3 mm (holotype carapace damaged; not measured). Roughly rectangular, straight dorsal and ventral margins, umbone prominent located on the anterior 1/3 rd of the carapace, carapace with 15 + distinct carapace lines, brown in coloration.

Trunk. Trunk consisting of 24 segments, each with a pair of thoracopods and decreasing in size posteriorly, the last 6 very small.

Thoracopods. As per the genus without any fingerlike exopodite projections, thoracopods 9 and 10 with long epipodites for carrying eggs.

Segments 13–24, each bearing bunch of stout posteriorly directed setae with acute apices, number increasing anteriorly first and then slightly decreasing, maximum of 5–7 setae seen per segment ( Figs. 5B , 7B ).

Telson. Broadly rectangular; dorsal margin gently arched, the lateral edge ending with a big spine, ~0.3 times the length of the cercopod; dorsal margin lined with about 30 irregularly sized spines but largest at the posterior end, largest spines ~2 times the length of smallest spines ( Figs. 6B , 7B ).

Cercopods. Long, about ~1.1 times the length of dorsal margin of telson, highly arched and tapering posteriorly; tip exceeding the posterior lateral projection of the telson; 2/3 rd of the anterior part of the dorsal margin gradually increasing posteriorly with largest spines densely packed, the last few (4–5) as long as the breadth of the thickest region of the telson spine ( Figs. 5C , 6B ).

Remarks. The female specimen (holotype) described here was used for obtaining sequences (few limbs), which were subsequently used to generate the phylogeny by Schwentner et al. 2020 (coded M089; Fig. 2 in Schwentner et al. 2020). Males of this species could not be obtained in the sediment rehydration. This species was still recognized as a distinct species because the unique head/cercopod morphology of the female amongst all the other Indian species. The cercopod structure of L. gomantaki resembles the Chinese species Leptestheria kunmingensis Shu, Rogers, Chen & Yang, 2015 female ( Shu et al. 2015). This species was seen to co-occur with Eulimnadia bondi, Padhye, Rabet, Kulkarni & Pagni, 2018 .

Figures

FIGURE 2. Occipital condyle shapes seen in Indian leptestherids. A. Rounded, B. Projecting, C. Prolonged.

FIGURE 5. Leptestheria gomantaki sp. nov. A. Head (female), B. Dorsal armature (female), C. Telson showing cercopod (female) (Scale bars 1mm for A, 0.5 mm for B,C).

FIGURE 6. Leptestheria chalukyae sp. nov. A. Telson (female); Leptestheria gomantaki sp. nov. B. Telson (female) (Scale bars 0.5 mm for A–B).

FIGURE 7. A. Leptestheria chalukyae sp. nov. Head (female), B. Leptestheria gomantaki sp. nov. Telson marginal spines (female).