Syllophopsis peetersi, Akbar & Bharti & Kanturski & Wachkoo, 2021

Akbar, Shahid Ali, Bharti, Himender, Kanturski, Mariusz & Wachkoo, Aijaz Ahmad, 2021, First record of the myrmicine ant genus Syllophopsis Santschi, 1915 (Hymenoptera Formicidae) from India with description of a new species, Zootaxa 4985 (3), pp. 403-413 : 405-412

publication ID	https://doi.org/ 10.11646/zootaxa.4985.3.7
publication LSID	lsid:zoobank.org:pub:2BDD3B3F-9A50-45FF-BE75-0082571F756F
DOI	https://doi.org/10.5281/zenodo.4956297
persistent identifier	https://treatment.plazi.org/id/03BF102C-FFF0-3559-FF5A-8E2BFBC5FD86
treatment provided by	Plazi
scientific name	Syllophopsis peetersi
status	sp. nov.

Treatment

Syllophopsis peetersi sp. nov.

( Figures 2–6 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 )

Types. Holotype worker: India, Kerala, Silent Valley National Park , 11.0939N, 76.4462E, Kerala, India, 900 m. a.s.l., 25.ix.2011, Winkler extraction method, leg. S.A. Akbar (unique specimen identifier PUAC5001 ) GoogleMaps . Paratypes: 6 workers with same data as holotype ( PUAC5002 – PUAC5007 ) GoogleMaps . Additional material examined: 14 workers, Silent Valley National park near Badriya Juma Masjid, Mukkali, 11.0618N, 76.5390E, Kerala, India, 700 m GoogleMaps .a.s.l., 20.xii.2016, Winkler extraction method; 8 workers ( PSAA0001 – PSAA0008 ) ; 2 workers (PSAA0009–PSAA0010 for molecular analysis, NMNH) ; 2 workers (PSAA00011–PSAA0012 for SEM studies, USKP) ; 2 workers, same data except: 21.xii.2016 (PSAA00013–PSAA0014 NHMUK), leg. S.A. Akbar.

Worker measurements (n=11; range with holotype in brackets): EL 0.11–0.13 (0.11), HL 0.68–0.73 (0.71), HW 0.58–0.61 (0.60), SL 0.50–0.52 (0.51), ML 0.65–0.77 (0.74), PRW 0.51–0.53 (0.52), PL 0.25–0.27 (0.26), PPL 0.22–0.24 (0.23), PPW 0.24–0.26 (0.25), PW 0.25–0.28 (0.27), PH 0.28–0.29 (0.29), PPH 0.25–0.26 (0.26) mm. Indices: CI 83–85 (84), SI 82–86 (85).

Worker Description. Head longer than wide (CI 83–85); vertex planar to slightly concave; frons shining and smooth with sparse piliferous pits and a few striolae around antennal sockets; frons with incurved and semierect setae ( Figs 2a View FIGURE 2 , 3a–b View FIGURE 3 ). Eye distinct, well developed, consisting of more than 9 ommatidia, eye width 1–2× greatest width of antennal scape, eyes set about midpoint of head capsule, more-or-less circular with curvature of inner eye margin slightly more pronounced than that of its outer margin, ommatidia of compound eyes are loosely and regular deployed having few curved sensilla in-between ( Figs 3c–d View FIGURE 3 ). The frontal lobes are well-separated and the anteromedian seta is situated well under a protrusive ledge ( Fig 3e View FIGURE 3 ). Clypeal carinae weakly defined with anteromedian clypeal margin narrowly convex between weakly ridged clypeal carinae; paraclypeal setae moderately long and fine, curved; posteromedian clypeal margin ending slightly anterior to antennal fossae. Mandibles with 4–5 teeth and one denticle (on second basal tooth); mandibles linear-triangular with few piliferous pits and distinctly striate; masticatory margin of mandibles strongly oblique ( Figs 3f–g View FIGURE 3 ); anterior tentorial pit is situated far away from the antennal sockets ( Fig 3h View FIGURE 3 ). The torulus appears as circular sclerites with a well marked torular lobe; placed within is antennal bulbus having series of sensilla trichodea ( Figs 3i–m View FIGURE 3 ). Antennae consist of 12 segments with a 3-segmented distinct club; scape, pedicel and flagellum are well separable ( Fig 4a View FIGURE 4 ). Compared with the rest of the antennal segments, the scape consists of fewer but longer pilosity ( Figs 4b–c View FIGURE 4 ). Pedicel and rest of the antennal segments mainly consist of curved sensilla trichodea, with some of them having grooved surfaces ( Figs 4d–i View FIGURE 4 ). The apical antennal segments which form the club also have few sensilla trichodea curvata (tc) along lateral sides ( Figs 4j–k View FIGURE 4 ). Most of the sensilla are concentrated along the apical flagellomere ( Fig 4l View FIGURE 4 ). The terminal flagellomere has a dense covering of sensilla trichodea curvata (tc), few sensilla basiconica (b) and some sensilla trichodea (t) ( Figs 4m –p View FIGURE 4 ). Most of the basiconica and sensilla trichodea appear paired ( Fig 4o View FIGURE 4 ). On the tip of terminal flagellomere there are also few small pores in the cuticle representing the openings of the sensilla ampullacea (a) and sensilla coeloconica (c) ( Figs 4p–q View FIGURE 4 ). The very tip of the flagellomere is characterised by very granulated or porous surface ( Fig 4r View FIGURE 4 ). The general surface of head consists of regularly placed sensilla trichodea throughout with gena mostly devoid of any distinct pilosity ( Figs 4s–t View FIGURE 4 ). The sensilla are strongly curved at the base and their sockets are quite tight ( Fig. 4u View FIGURE 4 ). Head cuticle is more or less ribbed ( Figs 4v–w View FIGURE 4 ). Pilosity near tentorial pits consists of short curved hairs ( Fig 4x View FIGURE 4 ).

Mesosomal outline in profile broadly convex and smoothly rounded, promesonotum slightly raised compared to propodeum ( Figs 2b–c View FIGURE 2 , 5a–b View FIGURE 5 ). Metanotal groove strongly impressed, with distinct transverse costulae ( Figs 5c–d View FIGURE 5 ). Mesosoma shining and smooth with faintly striolate mesopleuron posteriad. Promesonotal setae a mixture of incurved, semierect setae, slightly shorter decumbent setae, and sparse appressed setulae. Propodeum with dorsum longer than the posterior (declivitous) face; mostly smooth and shining with dorsum having few weak striolae; propodeum with erect to decumbent setae along dorsum and entire declivitous face; propodeal spiracle nearer to declivitous face of propodeum than metanotal groove; vestibule of propodeal spiracle distinct; propodeal lobes present as rounded flanges, metapleural gland with a distinct circular opening ( Figs 5e–g View FIGURE 5 ). Petiolar node cuboidal, shining and smooth throughout without any ventral rugae on the petiolar peduncle; petiolar spiracle situated anteriad of petiolar node ( Fig 5h View FIGURE 5 ); postpetiole shining and smooth; postpetiolar sternite depressed, anterior carina inconspicuous ( Fig 5i View FIGURE 5 ). Four distinct gastral tergites with sharp pointed sting; the terminal gastral segment has a circular stigma opening ( Figs 5j–m View FIGURE 5 ); gastral tergites, with a mixture of incurved, semierect setae and slightly shorter decumbent setae.

The legs with strongly swollen femur and a stout tibia, calcar, basitarsus, five tarsomeres and sharply pointed claws ( Fig 6a View FIGURE 6 ). The surface of leg shows presence of scattered sensilla trichodea (t). The protibial spur of forelegs (calcar of strigil) appears distinct with grooved squamiform and spatulate setae ( Figs 6b–j View FIGURE 6 ). Claws with long setae and arolium between the pointed claws in all the legs ( Figs 6k–m View FIGURE 6 ). The tarsomeres also have a dense covering of long sensilla trichodea ( Figs 6n–o View FIGURE 6 ).

Color yellowish to very light brown.

Distribution. Western Ghats, India.

Ecology. The specimens were collected by Winkler sampling carried out at Silent Valley National Park, a primary tropical rainforest in Kerala. Located in the Nilgiri hills of Western Ghats of India, the park represents one of the last undisturbed tracts of tropical moist evergreen forest in India (2d). The region has a mean annual rainfall of 6,066 mm and a mean annual temperature of 20.2 oC. The litter samples were taken from thick leaf litter and moisture laden soil near tree trunks, from two sites along the banks of the river Kunthi (Kunthipuzha). One site was in the buffer zone (Mukkali) and one in the core region (Sairandhri). The Sairandhri region forms the gateway of Silent Valley. The type locality of the new species is known for its ancient history and relict ant taxa ( Bharti & Akbar 2013a, b, c, 2015; Dad et al. 2019).

The majority of the species in the genus have been collected via Winkler sampling, inhabiting leaf litter from the tropical rainforests (AntWeb 2021), and same holds true for the new species described here. The species appears rare, with a restricted distribution. However, it is quite possible that the species occurs elsewhere in southern India and Sri Lanka, in areas with similar habitat.

Etymolog y. The species epithet honours the late Professor Christian Peeters and is a masculine genitive noun. The name ‘Peeters’ is derived from the Greek root word Petrus (‘rock’ or ‘stone’) which also appropriately symbolises the foundational stature of Prof. Christian Peeters’ work in the study of ants.