Introduction
Psammogeton Edgew. (Apiaceae) is a tiny genus that is mostly
limited to Asia and has a natural range that extends from Iran, Iraq,
and central Asia (Govaerts et al. 2021). As a traditionally
circumscribed the monophyly of Psammogeton is yet to be confirmed
(Mousavi et al. 2022). In India, the native range of Psammogetonspecies is lowlands of the Jammu of Jammu and Kashmir (Fig. 1). Almost
all the species of Psammogeton are adapted to dry rocky, stony,
sandy situations particularly margins of river beds. On the basis of
morphological and phylogenetic affinities Psammogeton is closely
related to its allied genus Aphanopleura . Psammogeton
anethifolium , P. biternatum , P. canescens , P.
diffusus , P. involucratum and P. shivalikense are the
species that constitute the genus in India. Psammogeton
biternatum , P. canescens , P. shivalikense and P.
suchaniense have all been identified in Jammu & Kashmir so far.
According to Boissier (1872), Clarke (1879), Drude (1998), Hiroe and
Constance (1958), Kitamura (1960), Heywood and Dakshini (1971), Nasir
(1972), Babu (1977) Ahmed and Koul (1979), Hamal and Koul (1980), Sharma
and Kachroo (1981), Hedge et al. (1987), Rechinger (1987), Mukherjee and
Constance (1993), Katz-Downie (1999), Downie et al.(2000, 2010), Pimenov
and Leonov (1993, 2004), Mohanan and Pimenov (2007), Assadi et al.
(2008), Ajani and Mozaffarian (2019), Pimenov et al. (2019), a review of
the taxonomic literature revealed that the species has not yet been
named. By examining taxonomic literature, the correctness of the species
and description has been verified. Further confirmation was also
acquired by consulting herbarium specimens housed in different national
and international herbaria throughout the world. By comparing these
specimens and reviewing relevant literature, including Hiore and
Constace (1958), Heywood and Dakshini (1971), Babu (1977), Sharma and
Kachroo (1981), Mukherjee and Constance (1993), Pimenov and Leonov
2004), it was determined that the species had not yet been reported.
This may be due to the species’ small size, patchy distribution in
highly disturbed dry riverbank areas, and proximity to international
borders where there are restrictions on free movement. The Tawi River
bank west of Jammu, close to Mandal, is the place where authors found
several unique sample specimens. During the field inquiry between 2018
and 2022, the location is quite near the Pakistani border. Based on
these factors, as well as comparative morphology and anatomical study,
the authors were able to identify and describe it as a new species.
The root, petiole, stem, and fruit of Apiaceae species exhibit sectetory
chambers (vittae) that may contain schizogenic fatty channels carrying
region, oil, or mucilage (Duman et al. 2000, Metcalfe and Chalk 1950).
Nevertheless, anatomical traits are not employed as morphological traits
in the Apiaceae family to differentiate between closely related species
and genera. (Urusak and Kizilarslan 2013). The size of the pericarp,
thickness, exocarp cell size, vittae, and the investigations revealed
several diagnostically significant characteristics of the fruit and its
velluculae in addition to a broad range of diversity in fruit morphology
and morpho-anatomical parameters among the analysed taxa. The research
under inquiry expands our understanding of stem and fruit morphology.
These data had little taxonomic relevance because the quantitative
values frequently overlapped. Micro-morphological characteristics, fruit
surface characteristics, and fruit architecture therefore seem to be
more useful for identifying species. In Apiaceae, the quantity and
configuration of vallecular and comissural vittae inside the pericarp
frequently play a significant role. Although this characteristic differs
among several species in this family, the size of the vittae appears to
be more informative. In addition, an identification key has been
prepared to represent the similarities and differences between the
closely related species of Apiaceae.