Bothriochloa pertusa (Linnaeus) Camus, 1931

Landge, Shahid Nawaz & Shinde, Rajendra D., 2021, Synopsis of the genus Bothriochloa (Poaceae: Andropogoneae) in India, Phytotaxa 516 (1), pp. 43-58 : 51-55

4- Bothriochloa pertusa (Linnaeus) Camus

Type: — “ Habitat in India orientali.” Lectotype: Herb. Linn. No. 1212.16 ( LINN!).

This species grows in several variable habitats from open grassland, rocky uplands, farmlands, gardens to within much disturbed city premises, chiefly in drier places. It forms a gregarious monospecific community in appropriate habitats in wild such as the open grassland or sometimes on road sides. The early young inflorescence is purplishpink in colour, owing to which the population of this grass acquires a peculiar phenotypic distinction that may be recognized at a considerable distance. The two forms are quite apparent in the fields: a tufted non-stoloniferous and a mat forming stoloniferous. The racemes in this species turn strikingly white on maturity and distribute thereby in disarticulating segments of spikelets or as a complete raceme unit. The leaves are congregated at the base with mild fragrance when crushed & lower glume of sessile spikelets hairy below the middle with a single (sometimes two pits in a linear line in which one in the middle and another just above it) very prominent and persistent pit. It may be confused with Bothriochloa ischaemum in the common habitats and herbarium, but can be distinguished with ease as leaves of the latter are odorless when crushed (only checked in fresh specimens) (vs. with a distinct smell in the former) and lower glume of sessile spikelets without a pit (vs. persistently pitted in the former). Kabeer & Nair (2009) noted an annual habit in this species from Tamil Nadu otherwise it is widely known as a perennial grass. The various forms described by many authors as varieties under this species are apparently not discontinuous variations and could be seen in a gradation in herbaria. The stature of the plant is variable in a considerable degree from sub-erect, geniculately ascending, and trailing to straggling over other vegetation around or on the ground. When trailing giving out roots from the lower nodes that can be bearded when young and glabrous in older plants. The lower glume of pedicelled spikelet without a pit ( Stapf 1917), with one or two pits ( Blatter & McCann 1935). The number of racemes in this species is apparently variable 3–8 very rarely ca. 15 in number. The pit of sessile spikelet contains within it a somewhat dense, transparent viscous substance during anthesis. The proper functionality of which has eluded many observations. However, it may serve well to the logic that it might be of some use during/for pollination; as a bribe for the pollen dispersal by insects, for wind does not take a bribe!

According to a botanical collector Lisboa, the inflorescence is scented.

Uses: — According to Duthie (1888) this grass is esteemed as a universal fodder grass both for grazing and stacking. It stands up to constant grazing and trampling, and is able to withstand moderate drought periods ( Bor 1960).

Chromosomal count: — 2n=60.

Distribution: — Almost throughout India.

5- Bothriochloa pseudoischaemum (Nees ex Steudel) Henrard

Type:— India orientalis, Heyne s.n. (Numer. List [Wallich] no. 8815).

In India, this species is known from Tamil Nadu & Karnataka ( Bor 1960, Kabeer & Nair 2009, Lakshminarasimhan et al. 2019). Hooker & Stapf (1896) treated Andropogon oryzetorum as a synonym under Bothriochloa pseudoischaemum . However, according to Bor (1960) A. oryzetorum has longer & more acuminate spikelets with longer joints and pedicel; the combination giving a differential facies to it. Based on these features, Bor proposed a new combination B. oryzetorum . According to Bor (1960), this species is so far endemic to Ceylon [ Sri Lanka], only known from one or two collections (Thwaites C. P. 3258, Ceylon) and it may be that it will eventually have to be reduced to B. pseudoischaemum . As both of these species have markedly pruinose leaves on under surface and terete sheath, it could be that a plant from Sri Lanka is mere a form of B. pseudoischaemum but to verify this hypothesis a detailed study needs an undertaking.

Distribution:— India (Tamil Nadu & Karnataka) and Ceylon [ Sri Lanka] ( Bor 1960, Kabeer & Nair 2009, Lakshminarasimhan et al. 2019).

6- Bothriochloa ischaemum (Linnaeus) Keng

Type:—“ Habitat in Europae australioris aridis.” Lectotype: Herb. Linn. No. 1211.26 ( LINN!).

The spikelets in this species, as a rule, never pitted but lower glume of sessile spikelets have a slight tendency towards shallow depression. It might be often confused for Bothriochloa pertusa but from which it usually differs in slight, may be inconspicuous, hairiness (setulose) on the nerves of the upper glumes and sessile spikelets always efoveolate ( Neamsuvan et al. 2009). It can also be otherwise differentiated from the latter in glabrous nodes. Its habit is extensively branched and rhachis considerably shorter 0.5–1.5 cm long. The nodes in this grass are usually glabrous but specimens with densely bearded/pubescent nodes have been segregated as var. songarica , which does not seem to have a stand. The species is known to introgress with B. bladhii forming a range of intermediates in the field where these taxa flourish in association. This species exhibits glabrous as well as hairy nodes; in case of the latter the hairs are much appressed unlike a close species Dichanthium annulatum ( Forsskål 1775: 173) Stapf (1917: 178) which differs in distinctly spreading hairs. It can also be differentiated from D. annulatum in reddish tinge of spiciform-raceme and narrower and acute lower glume of sessile spikelets (vs. blunt apices in D. annulatum ).

Uses: — This species is common in the plains of Northern India, and is generally considered to be a good fodder grass ( Duthie 1888).

Distribution: — North India & Peninsular India (Tamil Nadu).

7- Bothriochloa insculpta (Hochstetter ex A. Richard) A. Camus

Type: — “ Crescit in montosis provincial Chire (Quartin Dillon), et in terra sicca ad radices montis Selleuda, prope Adoua, mense Septembre [September] (Schimper).” Lectotype: ETHIOPIA, Tigray, Scholoda , 22 September 1837, Schimper 80 (US-76201 (fragment) image!).

This species sometimes has basal leaves in which a distinctive sweet odor is found. Such forms much often have been confused in the field for the most commonest species B. pertusa (also with a distinct odour in the leaves) whose lower glume of sessile spikelet is always, as a rule, densely hairy below the middle and the numbers of racemes are relatively fewer and shorter in length. According to De Wet & Higgins (1963) the two species are genetically apparently isolated and do not interbreed. They suggested that Indian representatives of B. insculpta could be more naturally treated as a variety of B. pertusa . Similarly, they also suggested that African B. pertusa should be considered as a variety under B. insculpta . The Indian representatives of these two species are distributed from West Pakistan through India to Indonesia, whereas African representatives are in that continent only ( Higgins 1964). Bothriochloa pertusa is mostly characterized by fewer racemes per inflorescence (very rarely ca. 15) than B. insculpta which can have as many as 20 racemes. Lower racemes in B. insculpta rarely exhibit secondary and tertiary branches to which the former never relates. Harlan (1963) reported that Indian B. insculpta is tetraploid or hexaploid whereas African representatives of this species are pentaploid or hexaploid. Hybrid data presented by De Wet et al. (1963) indicated that tetraploid, pentaploid and hexaploid collections of B. pertusa and B. insculpta are essentially obligate apomicts.

Occurrence of the cleistogamous spikelets has been reported in Bothriochloa insculpta wherein the number of stamens is reduced ( Fish et al. 2015). It is thought that the pit in the lower glume of sessile spikelets in Bothriochloa retains stamen emergence, thereby making the spikelets cleistogamous ( Heslop-Harrison 1961). However, their thought may be applied for the sessile spikelet which is hermaphrodite but then what could be the advantage of refraining stamens from emergence in pedicelled spikelets (staminate) where pits are sometimes present? Is it to prevent autogamy? If it is, then there is no transfer of pollen to other plants to attain xenogamy! We have seen ants around the pit which contains a somewhat transparent viscous liquid when the inflorescence is at its young stage. Whether the function of the ants is to strangely assist a pollen transfer for the bribe of a liquid is hard to tell, unless and until backed by meticulous empirical observations. This species is monophyletic and represents a case of speciation at a tetraploid level ( Sumadijaya 2015).

Certain forms of this species that occupy drier habitats have peculiar facies and with characters such as: leaves glaucous, densely pubescent with long bulbous-based hairs, lower leaves distichous, blades margin finely serrulated with a distinct whitish or a transparent band and lower glume of pedicelled spikelet with usually 1–2 depressions. These forms have short stature but form extensive mat on the drier grounds through gravels and stony soil. The leaves are always with a distinctively sweet odor. The extensive network of its stolons is interrupted by dense nodes in which leaves are clustered. Such forms, as far as we have seen in our surveys, are strictly confined to the rocky less fertile grounds away from the water sources in Deccan and geographically isolated from the commonly occurring larger forms of this species in wet places of Western Ghats. The forms of this species in wet areas especially near pond side, river side, wetlands and in open grasslands infrequently acquire a differential habit. There culms become wiry, drooping, long weak and somewhat straggling. However, we suppose the features are not enough to warrant any further distinction. We consider these forms under a plastic range of Bothriochloa insculpta .

Uses: — Probably of use as a fodder grass ( Bor 1960).

Chromosome count: — 2n=60.

Distribution: — Most of the parts of Peninsular India & North India (Bihar).

8- Bothriochloa parameswaranii Sreekumar, Malathi & Nair

Type: — INDIA, Kerala, Idukki District, Eravikulam National Park , alt. 6800 ft., February 14, 1981, P. V . Sreekumar 71858 ( CAL & MH!) .

Bothriochloa idukkiensis P. V. Sreekumar was an invalid name without a Latin diagnosis. Later, a new species B. parameswaranii Sreekumar, Malathi & Nair (1988: 163) published based on the same type of the former, but this time with a Latin diagnosis and the description. Therefore, the type specimens of the latter species ( P. V. Sreekumar 71858 image!) at K, CAL and MH are labeled with B. idukkiensis and have been seen. The authors of this species mentioned certain features in the protologue, such as, habit slender (up to 30 cm high), nodes glabrous, leaf blade ca. 10 × 0.2–0.3 cm, sessile spikelets 4.0 mm long, pits on the lower glume of pedicelled spikelet 1–4 (shallow not deep), joints and pedicel 2.0–3.0 mm long, and anthers 1.0– 1.25 mm long, which have been employed as taxonomic attributes to distinguish B. parameswaranii from the allied congener B. kuntzeana . We have studied all of these features in the variable range of B. insculpta ; its comparison with the latter is therefore reasonably invalid. It is further supported by Stapf (1917), who noted certain very important features in African representatives of B. insculpta , as, pedicel and rhachis internode almost equal about 1½ lin. (which is approx. about 3.2 mm long (Line= 2.1 mm )), lower glume of sessile spikelet glabrous and node long bearded. We have also seen this species with entirely glabrous nodes in some collections at BLAT and also in our personal collections from Maharashtra and Andhra Pradesh, India. It is therefore assumed that the character of a node may not be taxonomically significant in this plastic species. In B. parameswaranii rhachis is very short up to 1.0 cm only, habit slender, and with all the floral features it conforms to a greater degree with B. insculpta than B. kuntzeana . Since B. insculpta is highly variable in terms of its habit, indumentums and pits on the spikelets, it is easier to comprehend B. parameswaranii in the variable range of it. Based on our observations, the specific delimitation of the latter is apparently vague and thus we relegate it as a new taxonomic synonym (synonym nova) of B. insculpta . It is much closer to the African specimens of B. insculpta , which is evident in Stapf (1917).

Earlier, it was believed to be endemic to Kerala state. Since, we have considered it conspecific to Bothriochloa insculpta ; its distribution is as same as the latter.

Distribution: — As same as Bothriochloa insculpta .

9- Bothriochloa grahamii (Haines) Bor

Type: — INDIA, Central Provinces, Amakantak Hills, often gregarious in old jhumed lands (bewars), Haines 3646 ( K!).

A species about which little is known, represented only by the type collections from Madhya Pradesh, India at K. There appears to have no specimens of this grass in any Indian herbaria. This species is close to non-pitted forms of B. kuntzeana in general appearance, but differs from which in much branched habit, inflated sheaths and only 5 nerved lower glume of the sessile spikelet. Hitherto, it is only known from the type locality “Amakantak Hills” in Madhya Pradesh for which the collector (Haines) noted as “often gregarious in old jhumed lands (bewars)”. It suggests that it was once a common grass found in copious when Haines collected it in 1910. No one seems to have collected it from that locality after Haines. It seems to be a possible hybrid of B. bladhii . According to DeWet & Harlan (1970), it could be a possible hybrid between B. bladhii & Dichanthium annulatum .

Distribution: — Amakantak Hills, Madhya Pradesh; so far endemic to Madhya Pradesh ( Bor 1960, Lakshminarasimhan et al. 2019). It is represented only by the herbarium specimens of the type collection at K.

10- Bothriochloa ensiformis (Hook f.) Henrard

Type: — INDIA, Concan [Konkan], Dalzell s.n.

In this species the stem is stout, rigid, strongly laterally compressed and characterized by equitant leaf-sheaths; blades are strictly distichous, rigid, strongly nerved, linear-lanceolate, and acuminate. It is, so far, only known from Lonavla in Maharashtra, of which no collection exists in Indian herbaria except the type. It does not seem to have been collected for a long time, probably since Dlaziel’s time ( Bor 1960). This species can be easily mistaken for B. compressa which also has compressed sheath. It differs from which weakly in its glabrous sessile spikelet (sometimes slightly silky below the middle —fide Hooker f.), which in the latter is distinctly hairy below the middle. These two species only slightly differ from each other.

Blatter & McCann (1935) distinguished it from B. kuntzeana in having glabrous nodes and from B. concanense in broader leaf blade i.e. 12 mm broad (vs. only 3.0 mm broad in B. concanense ).

Distribution: — INDIA, Concan [Konkan, Lonavala?]; endemic to Maharashtra. This is a very rare species which has not been collected after Dalzell ( Bor 1960).

11- Bothriochloa compressa (Hook f.) Henrard

Syntypes: — INDIA, Deccan ; Lisboa (no 6. A. odoratus ) ( K). Deccan, Woodrow s.n. ( K!) .

This is a remarkably distinct species which is said to be aromatic. It is only known from Maharashtra. This grass has peculiar compressed sheaths covering long internodes, spikelets efoveolate, lower glume of sessile spikelet hairy below the middle and upper glume distinctly mucronulate to mucronate (Hooker & Stapf 1897). It is strange to relate a species collected from Pulni Hills in Kabeer & Nair (2009) to B. compressa of Hooker f. which has been reported by them as a new record for South India. A grass from Pulni Hills is little unusual as its lower glume of pedicelled spikelet has 3–4 pits and upper glume of sessile spikelet is simply acute. It is certain that the identity is in trouble for the South Indian grass, which to a considerable degree appears to be a robust form of B. kuntzeana except for its compressed sheath. Since no specimen was indicated by them, we could not trace the material to confirm the identification. This report is dubious and needs a careful study. Until further confirmation, when the specimen is traced, we assume B. compressa is only confined to Maharashtra.

“This is very striking plant, with long broad leaves and sharply keeled sheaths, has, strange to relate, been collected on two occasions only. It is said to be aromatic” ( Bor 1960). The collector Lisboa collected it from Deccan.

Distribution: — Deccan, Maharashtra; endemic to Maharashtra. No one seems to have collected it after Woodrow (type collector) ( Bor 1960).

12- Bothriochloa caucasica (Trinius) C. E. Hubbard

Type: — “ V. spp. e Cauc. orient.”

This is another species along with B. bladhii to have elongated rhachis longer than the racemes. Earlier, Hackel (1889) considered it as a variety of B. bladhii . Since, it may be readily distinguished for its lower lemma which is about half as long as the lower glume and shorter racemes that usually consist of fewer than 20 spikelets from the allied species B. bladhii . The other species of this group having an elongated rhachis generally tend to have longer racemes consisting of more than 25 spikelets ( Faruqi 1969). According to De Wet & Harlan (1966) this species is a part of compilospecies B. bladhii . According to Cope (1989) the distinction of this species with lower lemma alone is not sufficient enough to warrant a species rank.

Uses: — A very promising fodder grass and perhaps the hardiest in the genus ( Bor 1960).

Chromosome count: — 2n=40.

Distribution: — North-West India ( Bor 1960).

13- Bothriochloa bladhii (Retzius) Blake

Type: — “In China lectum cum aliis mislit bonorat, D. Bladh.” CHINA, Bladh s.n. ( LD).

This species possesses one of the most variable taxonomic complexes in the tribe Andropogoneae to beguile the attention of curious agrostologists. The rapacious promiscuity of this species with other taxa of the genus Bothriochloa , Capillipedium and Dichanthium has apparently blurred species delimitation. Almost all the species with elongated central axis (longer than racemes) are considered to have spontaneously arisen from B. bladhii hybridizing with others; for the detailed study refer DeWet & Harlan (1970). Faruqi (1969) has provided a comprehensive study on the range of variations in B. bladhii and its hybrids. It is highly reactive species and known to hybridize with Capillipedium, Dicahnthium , and Bothriochloa and with species, such as, B. ewartiana , B. bladhii and B. pertusa reproducing fertile hybrids ( Faruqi 1969). All sorts of intermediates are expected to encounter in the field.

In March 2020, during an expedition to Madhya Pradesh, the first author located an interesting population (Shahid Nawaz MP-01 & MP-02 at BLAT) of Bothriochloa species in the deep forest of Satpura range. This population was in discrete patches strictly confined to the forest shade in leaf litter. However, we could not trace any other congener in the vicinity. After a critical study on these specimens at BLAT, it revealed similarities with B. glabra and B. punctata . In sensu lato it can be considered in the variable range of a compilospecies B. bladhii . The description of a plant we collected is given as follows,

Habit tall, more than 6 feet high a coarse grass, extensively intravaginally branched, bases studded with numerous tough, pungent, glabrous cataphylls, leaves long and broad (ca. 1.3 cm), densely hairy when young (hairs caducous in older leaves, then blades becoming scabrous and more rough), inflorescence odorless panicle of racemes with long rhachis (ca. 9.5 cm long), axillary and terminal with fascicles of 3 or more peduncles, branches of racemes very slender, un-divided with a long bare portion (ca. 0.8–1.2 cm long) below the raceme, glabrous, racemes very slender 2.0– 4.2 cm long mostly deep purple, spikelets 3.0– 3.8 mm long, foveola one or two (if two then placed adjacently) shallow (not excavated), on both sessile and pedicelled spikelets (this feature is highly unreliable apparently variable in a single raceme base-upwards or in the panicle. There are certain forms when the spikelets are completely efoveolate). The lower glumes of both the spikelets are either completely glabrous or slightly or sometimes distinctly hairy below the middle.

Blatter & McCann (1935) discussed an interestingly confusing case on the identity of Haines’ and Stapf’s Bothriochloa glabra . They recognized that their specimen is a match for Stapf’s description from the Flora of Tropical Africa and not with Haines’ grass which appears to be an admixture of five varieties of Hackel ( var. genuinus , var. haenker , var. punctatus & var. glaber ) including one of his own ( var. hirta ). According to them, Stapf’s glabra is confined to only one of Hackel’s varieties i.e. var. punctatus and therefore is legitimate in a taxonomic point of view. Haines’ glabra is a complex of many varieties for which a legitimate name B. intermedia (which is Andropogon intermedius of Robert Brown) can be opted.

Uses: — According to Bor, var. glabra is a rather coarse grass but it is said to be a excellent fodder. Other varieties in this species also constitute to a good fodder value.

Chromosome count: — 2n=40 ( var. glabra ).

Distribution: — Most of the regions of Mainland India ( Lakshminarasimhan et al. 2019).

Range of morphological variations in three Dichanthium species endemic to Peninsular India:—

The following species were earlier considered under Bothriochloa but they lack a distinct translucent pedicel and rhachis internode in their spiciform-racemes. Their proper identification and phenotypic plasticity of forms have been discussed.