A taxonomic revision of the genus Astragalus L. (Fabaceae) in Zanjan province, Iran and describing a new species

Introduction

The genus Astragalus L. with nearly 3000, species is probably the largest genus among the flowering plants (Lock and Simpson 1991). Iran, possessing nearly 800 species, is one of the most important centre of diversity for this genus (Maassoumi, 1998). This study following previous investigations which focused on the genus Aastragalus in Iran (Maassoumi, 1986-2005; Podlech, 1999 and 2010; Podlech et al., 2001; Zarre et al., 2008) aims to increase our knowledge about the Mega genus in Zanjan area. Based on previous local revision, this province with about 75 species belonging to 25 sections (Maassoumi, 1986-2005; Podlech, 1999 and 2010; Podlech et al., 2001; Zarre et al., 2008) was distinguished as an important area with respect to the genetic diversity of this genus. According to this new collection, the realistic number of Astragalus species occurring in Zanjan province was increased to 116 belonging to 28 sections.

Material and methods

Zanjan province is situated in the NW Iran, with an approximate area of 2,216,400 hectars. The province with seven other provinces make a rich floristic zone presenting high number of endemic species. Climate of this province usually is cold and snowy in the mountain areas and moderate climate in the plains in winter. This province belongs to Irano-Turanian floristic region (Zohary, 1973) and presents its specific geographic, topographic and climate variation, also possesses suitable condition for the growth of several Astragalus sections including Hymenostegis Bunge, Incani DC., Malacothrix Bunge, and Caprini DC. (Podlech et al., 2001; Maassoumi, 1986-2005; Maassoumi, 2001; Bagheri, 2009; Ghahremaninejad and Bagheri, 2009; Ghahremaninejad et al., 2011; Bagheri et al., 2011; Maassoumi et al., 2011). This study was focused on the genus Astragalus especially sections Hemenostegis, Incani and Malacothrix. Allmaterials are deposited in TARI and FAR herbaria. In this research, more than 1200 herbarium specimens were collected within about 40 localities as demonstrated in table 1 (Figure 1).

Table 1: Locality information for Astragalus taxa examined

Figure 1: Geographical map of Zanjan province with main localities

Results

Abbreviations: A (Annuals species); H (Perennial herbaceous species); WO (Perennial woody species); EP (Endemic of Zanjan province); SP (Share with other province); SC (Share with other countries); NC (Not collected in this research, but have been reported in published literatures for Zanjan province); D ( species which were recently described); RP (New record for Zanjan province); RI (New record for Iran).

Annuals species

Annual species grow on limited parts of the province.

1. Section Ankylotus Bunge

A. commixtus Bunge (18) A, SC

2. Section Annulares DC.

A. campylorhynchus Fisch. & C.A.Mey.(9, 12, 13, 18, 19, 20, 21)A,SC

3. Section Heterodontus Bunge

A. guttatus [Soland.] (18) A, SC

4. Section Oxyglottis Bunge

A. crispocarpus Na'belek A, SC, NC

A. oxyglottisSteven ex M.Bieb. (1, 11, 12, 22)A, SC

A. schmalhausenii Bunge A, SC, NC

A. vicariusLipsky,(12, 15, 19, 22)A, SC, RP

5. Section Platyglottis Bunge

A. comptoceras Bunge (7, 17, 22, 24, 30, 35) A, SC, RP

6. Section Sesamei DC.

A. coronillaBunge, subsp. coronilla(7, 22) A, SC, RP

Perennial herbaceous species

7. Section Alopecuroidei DC.

A. echinops Auch. ex Boiss. (1) H, SC, RP

A. foliosus Podlech, Maassoumi & Ranjbar H, SP, NC

A. macrocephalus Willd. subsp. macrocephalus (1) H, SC

A. megalotropis C.A.Mey. ex Bunge SP, NC

8. Section Astragalus

A. caraganae Fisch. & C.A.Mey. (1, 4, 15, 20, 22, 24, 25) H, SC

9. Section Caprini DC.

A. aegobromusBoiss. & Hohen (1, 22, 23, 29, 34) H, SC, RP

A. angustiflorus K. Koch subsp.angustiflorus (1, 2, 17, 20, 29, 34)H, SC

A. apricusBunge (1, 15, 23, 32) H, SC, RP

A. chrysanthus Boiss. (1) H, SP

A. citrinus Bunge subsp.citrinus (17) H, SC

A. kirpicznikoviiGrossh. (24, 30) H, SC, RP

A. macropelmatus Bunge subsp. macropelmatus (4, 7, 10, 11, 13, 21, 22, 28) H, SC

A. multijugus DC. (1, 2, 16, 29) H, SP

A. ovinus Boiss. (1, 7, 9, 14, 27, 29) H, SC

A. pseudoutriger Grossh. H, SC, NC

A. semilunatus PodlechH, EP, NC, RP

A. shemachensisKarjagin,(6, 9) H, SC, RP

A. urmiensis Bunge (1, 2, 5, 15, 22, 29, 34) H, SC

10. Section Corethrum Bunge

A. dendroproselius Rech.f. H, SC, NC

11. Section Dissitiflori DC.

A. argyroidesBeck(21, 22, 32) H, SC

12. Section Erioceras Bunge

A. pentanthus Boiss. (20, 22) H, SP

13. Section Hololeuce Bunge

A. alyssoides Lam. (1, 2, 4, 7, 16, 19, 22, 23, 28, 29, 32, 34, 35) H, SC

Based on our collection, this species is extensively distributed at high altitude in several localities of the province.

14. Section Incani DC.

A. abharensis Maassoumi & Podlech (7, 15) H, EP

A. alavaanusPodlech(1)H, SP

A. andabadensis Maassoumi, Bagheri & F.Gharem. (13) H, EP, D

A. askius Bunge (1, 5) H, SP, RP

A. curvirostris Boiss. (1, 2, 5, 7, 9, 11, 16, 17, 20, 22, 24 28, 29, 30, 34, 37) H, SC

A. delutulides Maassoumi, F.Ghahrem., & Bagheri (6) H, EP, D

A. delutulus Maassoumi (23) H, SP, RP

A. fausicolaPodlech exBagheri, Maassoumi & F.Ghahrem., sp.nov. esect. Incani DC. (Fig. 2).

Typus: Zanjan: Gheidar, Gheidar Mt., 2430m, 2009/07/10, Bagheri 9064. (Holotype, TARI; Isotypes, FAR, MSB).

Sed differt ab A. askius Bunge bracteis glabris vel margin remotiusculi glandulosi vel raro sparse ciliatis (nec manifest ciliatis), foliolis angust ovatis vel rhomboidis, magnis c. 40-50 mm longis apicem versus long acutis vel subaristatis (nec obtusis vel breviter acutis), corolla intense violacea (nec lutea), legumnibus dorso manifest rotundatum (nec sulcatum) non purpureo punctato provisum.

Plants 30-50 cm tall, with symmetrically medifixed deppressed hairs 0.3-0.5 mm long. Caudex 8-11 mm in diameter, with few short branches, covered with remnants of old leaves and stipules. Stipules triangular to narrowly triangular-acuminate, 8-14 mm lang, adnate to the petiole for 5-7 mm, hairy. Leaves 10-25 cm long; petiole 3-11 cm long, like the rachis finely striate, loosely to rather densely hairy, later on glabrescent. Leaflets in 8-13 pairs, narrowly ovate, 10-50 × 4-20 mm, sharply acute to apex. Mostly aristate, sparsely to loosely, rarely rather densely hairy on both sides. Peduncle 15-30 cm long, thick, finely striate, glabrous. Raceme loosely many flowered, 15-20 cm long. Bracts brownish, linear-acute, 3-4 mm long, sparsely ciliate, glabrous, glandulosa or rarely sparsely ciliate on the margin. Pedicels ca. 3 mm long, Flowers erect, later becoming spreading or deflexed. Bracteoles whitish, linear, ca. 1 mm long, at the base of the calyx. Calyx 8-13 mm long, tubular, obliquely acute at the mouth, covered with deppressed black hairy; teeth narrowly triangular, acute, unequal, 1-2 mm long. Corolla violet. Standard c. 20 mm long; blade minutely narrowed, 10 mm wide, elliptic, at the base abruptly narrowed into a cuneate claw. Wings 15-17 mm long; blades narrowly oblong, rounded to obliquely retuse, at apex 8 × 3 mm; auricle 1.5 mm long, claw 9-10 mm long. Keel 15mm long; blades elliptic, acute at the apex, 8 × 4 mm; auricle very short, claw 9-10 mm long. Ovary with a short or distinct stipe up to 4 mm long, linear, scarcely hairy to glabrous. Legume with a 3-4 mm long stipe, pendulous, linear, straight or slightly upcurved, 18-35 mm long, 2-3 mm high und 3-5 mm wide, carinate ventrally, distinctly rotundate dorsally, at the apex narrowed into a straight beak 2-4 mm long; valves yellowish, without dark spots, glabrous. Fruit fully bilocular. Seeds rectangular, 3-5 × 2-3 mm, dark brown.

A. khadem-kandicus Maassoumi & Podlech (2) H, SP

A. montis-queydari F.Ghahrem.,Maassoumi & Bagheri (1) H, EP, D

A. qeydarensis Podlech (7) H, EP (ined)

A. refractus C.A.Mey. (14) H, SC, RP

A. supervisusSheld. (1, 28, 29, 32, 35, 40) H, SC

A. zanjanensis Podlech & Maassoumi (9, 33) H, EP

15. Section Laxiflori Kirchhof

A. dictyolobus C.A.Mey. ex Bunge (9) H, SP

A. tawilicus C.C.Towns. H, SC, NC

16. Section Malacothrix Bunge

A. beckii Bornm. (1, 23, 29) H, SP

A. belgheisicoides Podlech & Maassoumi (7, 16, 33, 34) H, EP

A. belgheisicus Maassoumi (27, 32) H, EP

A. comosus Bunge (1, 32) H, SC

A. singarensis Boiss. & Hausskn. ex Boiss.(1, 22)H, SP

A. eriocarpusDC. H, SC, NC

A. eriopodusBoiss.(20, 24) H, SC

A. hendelanicus Maassoumi (11, 18) H, SP

A. iranicus Bunge (7, 11, 12, 35) H, SC

A. macrourus Fisch & C.A. Mey. (1, 2, 23) H, SC

A. meshkinensis Podlech H, EP, NC

A. patriusMaassoumi (1, 17, 25, 35) H, SP

A. pileh-khasehensis Podlech & Maassoumi H, EP, NC

A. podocarpusC.A. Mey.(17) H, SC

A. saccatusBoiss. (28) H, SP

A. senilisBornm. (1, 2, 4, 8, 11, 15, 20, 22, 23, 28, 32) H, SP

17. Section Onobrychoidei DC.

A. aduncus Willd. H, SC, NC

A. brevipes Bunge H, SP, NC

A. effusus Bunge H, SP, NC

A. pendulipodus Ranjbar & Karamian H, SP, NC

A. vegetus Bunge (1, 7, 8, 9, 32, 40) H, SC

18. Section Ornithopodium Bunge

A. brachyodontusBoiss. (1, 7, 8, 9, 12, 15, 17, 18, 19, 27, 30, 38) H, SP

A. glochideus Boriss. (1, 2, 4, 9, 10, 13, 16, 17, 23, 24, 27, 32, 33) H, SC

19. Section Stereothrix Bunge

A. mahneshanensis Maassoumi & Mousavi H, EP, NC

20. Section Theiochrus Bunge

A. siliquosusBoiss. subsp.siliquosus(1, 8, 15, 35) H, SC

21. Section Uliginosi Gray

A. odoratus Lam. (6) H, SC

22. Section Trachycercis Bunge

A. barnasariformis Maassoumi, F.Ghahrem. & Bagheri (5) H, EP, D

Perennial woody species

23. Section Adiaspastus Bunge

A. aureus Willd. WO, SC, NC

A. caspicus M. Bieb. subsp. caspicus(1, 2, 3, 4, 5, 7, 9, 10, 11, 13, 14, 29, 39)WO, SC

A. michauxianus Boiss. (1, 2, 4, 5, 8, 16, 34) WO, SC

A. polyanthusBunge (1, 7, 10) WO, SC, RP

24. Section Anthylloidei DC.

A. ebenoides Boiss. subsp. ebenoides WO, SP, NC

A. halicacabusLam. (22) WO, SC

A. submitisBoiss. & Hohen. subsp.submitis (1, 2, 7, 10, 23) WO, SP, RP

25. Section Cremoceras Bunge

A. campylanthoides Bornm. (7, 10, 32) WO, SC 

26. Section Hymenostegis Bunge

A. anguranensis Podlech & Maassoumi (6, 27) WO, EP

A. austromahneshanensisF.Ghahrem.,Maassoumi, & Bagheri (32)WO, EP, D

A. bounophilus Boiss. & Hohen. (5, 6) WO, SP

A. chrysostachys Boiss. (4, 5, 9, 11, 21, 22, 32, 37) WO, SC

Within the sect. Hymenostegis, this species shows a wide-ranging distribution in the major parts of the province from other related species.

A. demonstratus Maassoumi (37) WO, EP

A. glumaceus Boiss. (4, 7, 15, 21, 22, 32, 38) WO, SP

A. kapherrianus Fisch. WO, SC, NC

A. lagopoides Lam. (17) WO, SC, RP

A. marivanensisMaassoumi & Podlech (4, 32) WO, SP, RP

A. melanostictus Freyn (4) WO, SC

A. nervistipulus Boiss. & Hausskn. ex Boiss. (1, 3, 4, 7, 8, 9, 17, 22, 35) WO, SP, RP

A. paralurges Bunge (1, 3, 7, 10, 15, 16, 21, 22, 24, 26, 30, 35) WO, SP

Widely distributed in the mountainous area mixed with Tragacanthic species.

A. pauxillis Maassoumi & F. Ghahrem. (1) WO, SP

A. pediculariformis Maassoumi (1, 3, 7, 23, 29) WO, EP

A. qorvehensisPodlech (1)WO, SP, RP

A. qeydarnabiensisBagheri, F.Ghahrem. & Maassoumi (1)WO, EP, D

A. rubrostriatus Bunge (1, 7, 9, 10, 17, 24, 25, 29, 33, 35) WO, SP

A. sciureus Boiss. & Hohen. (1) WO, SP

A. sosnowskyiGrossh.(21) WO, SC, RI

Type species previousely reported from Iraq, based on new collection, this species as a new record for Iranian territory.

A. subkohrudicusMaassoumi, F.Ghahrem. & Bagheri (1)WO, EP, D

A. subrecognitusBagheri, Maassoumi & F.Ghahrem. (20) WO, EP, D

A. tabrizianus Buhse (16, 17, 30, 32) WO, SP

27. Section Rhacophorus Bunge

A. andalanicus Boiss. & Hausskn. ex Boiss. (1, 2, 23) WO, SC, RP

A. compactus Lam. (1, 2, 4, 5, 16, 22, 23, 26, 29, 32, 38) WO, SC

A. denudatus Steven WO, SC, NC

A. eriosphaerus Boiss. & Hausskn. ex Boiss. (9, 16, 22, 25, 36, 37, 38, 39) WO, SP

A. floccosus Boiss. subsp. floccosus(9) WO, SP

A. gossypinus Fisch. (1, 3, 7, 21, 22, 23, 29, 32, 36) WO, SC

A. microcephalusWilld. subsp. microcephalus (1, 2, 3, 7, 10, 11, 12, 15, 16, 17, 22, 23, 29, 32, 36) WO, SC

This species shows a wide-ranging distribution in the mountainous area, up to 1800 m and with other tragacanthic species such as: A. eriosphaerus, A. gossypinus, and A. campactus create a mixed associations.

A. paralipomenus Bunge (1, 4, 5, 7, 8, 14, 15, 16, 17, 20, 29, 36) WO, SC

A. psilostylus Bunge WO, SP, NC

A. rhodosemius Boiss. & Hausskn. (23, 40) WO, SP, RP

A. verus Oliver, (16, 27, 34) WO, SC

28. Section Tricholobus Bunge

A. tricholobus DC.

subsp. tricholobus (1, 2, 5, 7, 9, 10, 16, 17, 20, 22, 23, 26, 27, 29) WO, SP

subsp. hohenackeri (Boiss.) Tietz(16, 27)WO, SC

Figure 2: A. fausicola Podlech exBagheri, Maassoumi, & F.Ghahrem.; (after Holotype, Bagheri 9064)

Discussion

In total, 116 distinct species of Astragalus were recognized in Zanjan province. They include 9 annuals species (7.75%), 65 perennial herbaceous species (56.03%) and 42 perennial woody species (36.20%).

Among 116 species, 22 spp. (18.96%) belong to sect. Hymenostegis, 16 (13.79%)species to sect. Malacothrix, 14 (12.06%) species to sect. Incani, 13 (11.20%) species to sect. Caprini, 11 (9.48%) species to sect. Rhacophorus, and 40 (34.48%) species belonging to the other sections which are illustrated in fig. 4. In the point of endemism percentage the province are divided into 3 groups: 1- containing 21 spp. (18.10%) are endemics for the province; 32 spp. (27.58%) are shared with other provinces; and 63 spp. (54.31%) are shared with other neighboring countries.

Figure 3: Life form of Astragalus species in Zanjan province

Figure 4: Sectional profile of Astragalus species in Zanjan province

Acknowledgment

We are grateful to Dr. Mohammadreza Rahiminejad Ranjbar (University of Isfahan) for editing the english text.