Streptocephalus warliae Katke, Padhye & Vanjare, 2025

Katke, Prashant Manohar, Padhye, Sameer M. & Vanjare, Avinash Isaac, 2025, A new species of Streptocephalus Baird, 1852 (Crustacea, Branchiopoda) from Peninsular India, Zoosystematics and Evolution 101 (3), pp. 1259-1269 : 1259-1269

publication ID	https://doi.org/10.3897/zse.101.139357
publication LSID	lsid:zoobank.org:pub:7751AC4D-30D8-4671-A16A-75D229BEC203
DOI	https://doi.org/10.5281/zenodo.16414159
persistent identifier	https://treatment.plazi.org/id/73ED0D81-3460-5B56-B9A6-B0F78E3F3E8C
treatment provided by	Zoosystematics and Evolution by Pensoft
scientific name	Streptocephalus warliae Katke, Padhye & Vanjare
status	sp. nov.

Treatment

Streptocephalus warliae Katke, Padhye & Vanjare sp. nov.

Figs 2 View Figure 2 , 3 View Figure 3 , 4 View Figure 4 , 5 View Figure 5 , 6 View Figure 6 , 7 View Figure 7

Type material.

Holotype • 1 male ( ZSI-WRC C.2582 , Zoological Survey of India, Pune, India) . Allotype • 1 female ( ZSI-WRC C.2583 Zoological Survey of India, Pune, India) same data as holotype . Paratype • 2 males ( ZSI-WRC C.2584 , Zoological Survey of India, Pune, India) same data as holotype. Preserved in alcohol .

Diagnosis.

Streptocephalus warliae sp. nov. belongs to the “ S. dichotomus ” species group and can be separated by the following characters: second antenna distal antennomere with an obtuse, subconical, basomedial projection. Antennal appendage peduncle with 4–5 elongate, dorsobasal papillae in a subtransverse row, each papilla conical and flexible, with all but the lateralmost one smooth, extending halfway along the peduncle. Lateral most dorsobasal papilla distoventrally with longitudinal row subpapillae, reaching to end of peduncle. Peduncle dorsomedially with longitudinal row of 11–14 spiniform processes reaching base of “ hand ”. The margin of the posterior lateral branch (lower finger) is smooth. The margin of the posterior primary branch (upper finger) of the posterior ramus (finger) bears major and minor spines, divided distally into two unequal apical rami (digits) with the upper ramus at a sharp 90 - degree angle with the primary branch. The curved upper rami are pustulate, whereas the lower straight rami margin is with unequal-sized aciculate spines. Posterior branch (spur) of the anterior ramus (thumb) ends in unguiform structure distally. Anterior ramus without a distal triangular projection. Female second antenna with a distinct deep notch towards the apical end.

Description of the holotype.

Average body length (from front of head to tip of telson) 19.1 mm (n = 20), range 11–26 mm (Fig. 2 A View Figure 2 ).

Head typical for genus, frontal appendage, triangular, simple and short. First antenna filiform, length 35 % longer than second antenna proximal antennomere; apex pointed with 7 small setae at the tip and 3 long setae subapically.

Second antenna typical of the genus (Figs 2 A View Figure 2 , 3 A, B View Figure 3 ). A distinct triangular basomedial projection at the base of distal antennomere (Figs 3 A, B View Figure 3 , 5 A View Figure 5 ). Antennal peduncle with anteriomedial dorsobasal papillae, 4 (30 %) – 5 (70 %) in number, with papillae ventrally, reaching end of peduncle (Figs 3 A View Figure 3 , 5 A, B View Figure 5 ). Antennal appendage peduncle laterally with 11–14 spiniform processes (slender process) (Figs 3 A View Figure 3 , 5 A, B, D View Figure 5 ). Length of the longest spiniform processes 1.8–2.0 mm, subequal to length of proximal antennomere. Peduncle anteriomedially and ventrally (near the spiniform processes) with triangular protuberances; eight such protuberances ventrally and six anteriomedially (Fig. 5 B, C View Figure 5 ). Antennal appendage apical cheliform structure (hand), not broadened at the base of the anterior ramus (Figs 3 A, B View Figure 3 , 5 D View Figure 5 ). Anterior ramus and posterior branch without spines. Anterior ramus without distal lamellar projection (Figs 3 A, B View Figure 3 , 5 D View Figure 5 ). Anterior ramus posterior branch broadly lamelller, not constricted apically, ending in ungiform structure (Figs 3 A View Figure 3 , 5 D View Figure 5 ).

Posterior ramus ventral margin with emargination near to the confluence of both rami, emargination ~ 1.2 times as deep as wide (Fig. 5 D View Figure 5 ). Posterior ramus branched / biramous, length ~ 1.2 times anterior ramus. Posterior ramus with a dorsolateral (lower) arcuate subramus (Fig. 3 A View Figure 3 ). Posterior primary branch bearing acute major and minor spines, major spines up to ~ 6 times longer than minor. Primary branch distal end divided into two unequal apical rami (Figs 3 A, B View Figure 3 , 5 A View Figure 5 , 6 A View Figure 6 ). The curved upper rami arcuate, margin smooth, with or without small basal spines, distal 50 % pustulate, and angled 90 degrees from posterior primary branch. The lower straight ramus ~ 1.2 times smaller than the upper ramus, lined with unequal aciculate spines in proximal half of proximal region (Fig. 4 A View Figure 4 ). Posterior lateral branch margin smooth (Fig. 3 A, B View Figure 3 ).

Trunk limbs typical for genus (Fig. 4 C, D View Figure 4 ). Endite 1 of first and fifth pair of limbs with filter comb and, at posterior side, with scraping spine and naked tactile seta.

Genital segment and gonopods as in S. dichotomus group. Genital segments smooth, with lateral linguiform outgrowths. Gonopod cylindrical, with a basomedial spiniform outgrowth, bearing four denticles medially (Fig. 5 E View Figure 5 ).

Abdomen and cercopods as in S. dichotomus group (Fig. 2 A View Figure 2 ).

Description of the allotype (female).

Body slightly smaller than male, body length from 13.0–21.0 mm, average 17.3 mm (Fig. 2 B View Figure 2 ).

First antenna 2.4 times length of eye plus peduncle, 1.2 times length of second antenna, apex pointed with 4–7 small at the tip, three long setae just below the apex (Fig. 7 D View Figure 7 ).

Second antenna slightly broad, elongated (length-to-breadth ratio is> 1.9 measured from centre), spatulate, with sparse setae on the distal margin and a distinct notch near the apical end (Figs 6 A, B View Figure 6 , 7 A View Figure 7 ).

Cercopods setose (Fig. 6 D View Figure 6 ).

Ovaries uniramous; brood pouch elongate and fusiform; extending from segment III to half of segment V. The genital opening of the pouch terminal (Fig. 6 C View Figure 6 ).

Description of Egg.

Eggs spherical; surface with irregular and variable polygons; ridges raised, central field depressed; ~ 180 μm in diameter (Fig. 5 F View Figure 5 ).

Ecology.

The roadside basaltic rock pool was 6 × 3 m in area and ~ 1 m deep. It has submerged vegetation ( Hydrilla sp. ), tadpoles, and aquatic beetles. No other large branchiopods were seen co-occurring with this species. The pool is surrounded by many such smaller pools and a few small stone quarries. The cattle utilise the pool for both drinking and bathing, and as a tourist spot, the area attracts many visitors. The water temperature ranged between 22.0 ° C and 23.9 ° C, pH between 7.2 and 7.4, and salinity between 27 ppm and 36 ppm.

Etymology.

The name is dedicated to the indigenous ‘ Warli tribe’ residing in and around the type locality. The tribal women are known for creating distinctive wall paintings, popularly known as the “ Warli painting, ” using natural materials like rice paste, gum, and red soil. The use of circles, triangles, and squares in the paintings reflects their close association with “ mother nature. ”

Distribution.

This newly discovered species is currently known only from its type locality, an unnamed roadside pool situated on the lateritic plateau in Jawahar, Palghar district, Maharashtra state ( India). Elevation 420 m, coordinates 19°53'09.1"N, 73°11'25.5"E.

Remarks.

The male second antenna morphology of this species partly resembles that of S. sirindhornae and S. dichotomus . Still, this species possesses certain unique characteristics not observed in either. This species stands out from all other Indian species by the presence of a distinct triangular basomedial projection present at the base of the proximal antennomere, while the characters like a) aciculate minor and major spines on the posterior primary branch margin, b) sharp 90 ° angle of the upper bifid ramus to the posterior primary branch, and c) lower bifid ramus margin of the posterior primary branch with spines instead of pustulations separate the species from S. sirindhornae . The absence of distal lamellar projection on the anterior ramus and protuberances on the ventral and anteriomedial sides of the peduncle and the deep notch on the female second antenna apical end are other characteristics that separate S. warliae sp. nov. from the other Indian Streptocephalus species (see Table 1 View Table 1 for important differences). The apical setal number on the second antenna in the females with 4–7 short subequal setae on the apex (eight in S. sahyadriensis and 5–8 in S. dichotomus ) and with three long and subequal setae right below it in our specimens, S. sahyadriensis and S. dichotomus . In S. shinsawbuae Shu, Rogers, Chen & Sanoamuang, 2018 , only the three long setae were documented (see Shu et al. 2018). The genital opening of the pouch is in the terminal region, whereas Kraus et al. (2004) reported it to be subterminal in S. torvicornis (Waga, 1842) .