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The following points highlight the ten families under which coniferales has been classified. The families are:- 1. Lebachiaceae 2. Voltziaceae 3. Palissyaceae 4. Cheirolepida Ceae 5. Protopinaceae 6. Taxodiaceae 7. Cupressaceae 8. Araucariaceae 9. Podocarpaceae 10. Cephalotoxageae.
Family # 1. Lebachiaceae:
The family Lebachiaceae, based on the genus Lebachia and formed by Florin out of Upper Carboniferous and Permian fossils preciously assigned to the next family Voltziaceae, is the best known of the fossil families and throws some light on the origin of the Conifer-ales.
The different form genera which go in to form this plant are Walchia, Walchiostrobus, Walchianthus, Gomphostrobus, Pollenites and completely vegetative organs like Palaeotaxites and Buriadia. Ernestiodendron is a different plant also placed within this family.
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Lebachia was a tree with pinnately arranged branch-lets on which very small (a few mm long) needle-like leaves were borne spirally in an imbricate manner (Fig. 705A). Sometimes the needle leaves were bifurcate at the apex. The cones or inflorescences were cylindrical or ovoid at the tips of the branches. There were separate male and female cones.
The cone axis bore spirally arranged bifurcate bracts (called Gomphostrobus) at the axils of which were the fertile dwarf shoots. A female fertile shoot (Fig. 705B & C) bore on its axis a few scaly appendages only one of which was fertile with a single terminal ovule. The ovule was notched at the apex and the two sides expanded into wings in the mature seed.
Ernestiodendron was generally similar to Lebachia but the axillary female dwarf shoot was reduced to a fan-shaped 3- or 4-lobed structure each lobe of which bore a terminal ovule (Fig. 705D).
Lebachiaceae is the best known of the earliest conifers which, along with the Cordaitales, arose about the Carboniferous and became, more established in the- Permian when the earlier swamps were vanishing because of a spell of drought.
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Buriadia sewardiana, which probably belongs to this family, is known from the Indian Lower Gondwana (Karharbari— Lower Permian and Raniganj— Upper Permian Stages).
Family # 2. Voltziaceae:
The Voltziaceae (after taking out the Lebachiaceae) shows a group of fossils from the Permian to the Jurassic. The Upper Permian Pseudovoltzia shows dimorphic leaves, those on the lower stem are shorter while those on the upper parts are longer and more flattened.
The female dwarf shoot is in the axil of a simple bract and is dorsiventrally flattened into five partially fused scales on the upper surface of which are three stalked, recurved ovules (Fig. 706A & B).
In Ullmarmia (also Upper Permian) the female dwarf shoot is further reduced. On the axil of a single simple bract there is a single round, flat fertile scale (probably formed by the union of several sterile appendages) on the upper face of which is a single recurved ovule (Fig. 706C).
In the Lower Triassic Voltzia there are five flat scales as in Pseudovoltzia but three of them are fused with the three ovules. A sectional view shows the structure to be near the modern conifers (Fig. 706D).
Voltziaceae proper is represented in India by Moranocladus oldhamii (Karharbari— Lower Permian) in the Lower Gondwana and by Pagiophyllum peregrinum, Brachyophyllum expansum and B. rajmahalensis (Rajmahal—Lower Jurassic, Kota and Jabalpur—Upper (Jurassic) in the Upper Gondwana.
Family # 3. Palissyaceae:
The Upper Triassic and Jurassic, genera Palissya and Stachyotaxus are placed in this family. The female tranch of Palissya shows about ten distichously arranged ovuliferous axes each in the axil of a large bract. Each such ovuliferous shoot bears a fertile appendage (ovuliferous scale) bearing two rows of erect ovules on short side proliferations.
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This fertile appendage does not appear to be fused with the – sterile bract below (Fig. 707A). Stachyotaxus ovuliferous shoots are similar but more reduced in showing two ovules only.
Palissya is well represented in the Indian Upper Gondwana by Palissya conferta, P. indica and P. jabalpurpsis from the Rajmahal, Kota and Jabalpur Stages (Jurassic).
Family # 4. Cheirolepida Ceae:
This is a family of Triassic-Jurassic fossils which is very close to the Podocarpaceae and also related to the Araucariaceae. Only the female cones are known. In a female cone of Cheirolepis (Fig. 707B) the bract scale is digitately five-lobed.
On the upper surface of this, on the top of the lobes, two fertile scale are fused each of which extends down in an epidium which forms a pocket enclosing the ovule keeping it open only at the micropyle (Fig. 707C).
Family # 5. Protopinaceae:
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Protopinaceae is an assorted group of coniferous wood fossils mainly from the Jurassic and the Cretaceous which shows more or less distinct affinities with Pinaceae, Taxodiaceae, Cupressaceae and Podocarpaceae. Among them may be named Proto- podocarpoxylon, Protophyllocladoxylon, Protocedroxylon, Pinoxylon, Protocupressinoxylon and Piceoxylon.
The fossils families show the evolution of the Coniferales especially as seen in the female cone. These began in the Carboniferous inflorescences, viz., those of Cordaitales like Cordaianthus where the dwarf shoots were arranged in two rows on the axis and then in Lebachiaceae where the arrangement was spiral.
The dwarf shoots or individual female ‘flowers’ were radial and distinct in the Lower Permian.
There were rapid changes by the Upper Permian evolving the dwarf shoot of Ullmannia where the sterile scales fuse and form a discoid scale not unlike the Pinaceae. This bract and the fertile scale then show different degrees of fusion. Thus, the sterile bract and the ovuliferous scale of the Pinaceae seem to have been evolved from what was originally a radial dwarf shoot.
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Finally, different variations seem to have evolved the different Coniferale families which are extent today.
Family # 6. Taxodiaceae:
Taxodiaceae also is a family of trees with small needle-like to falcate or scaly leaves borne spirally. Cones are small with spiral members. Bracts and ovuliferous scales are almost completely fused. There may be 2 to 9 ovules on an ovuliferous scale. Pollens are wingless.
There are 10 genera with about 15 species:
Tribe Sequoiea:
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Genera: 1. Sequoia (Redwood— 1 sp.): from California (Fig. 728A). Remarkably gigantic ancient trees. Spread to Europe, Asia and other parts of North America in the Cretaceous and Tertiary.
2. Sequoiadendron (Bigtree—1 sp.): California to Sierra Nevada. Also a huge tree.
Tribe Metasequoiae:
Genus: 3. Metasequoia (1 sp.): previously known only as Cretaceous and Tertiary fossils, later dominant in the Eocene Arctic vegetation. Now known to exist in Central China and hence called a ‘living fossil’.
Tribe Taxodieae:
Genera: 4. Taxodium (3 spp.): S. E. United States and Mexico. Grows in forests which often remain flooded with their swollen bases under water.
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5. Glyptostrobus (1 sp.): S. E. China.
Tribe Cryptomerieae:
Genus: 6. Cryptomeria (1 sp.): Japan (Fig. 728B). It has been introduced into Darjeeling where it is now the commonest conifer.
Tribe Curminghamieae:
Genus: 7. Cunninghamia (2 spp.): China and Taiwan.
Tribe Sciadoptiyeae:
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Genus: 8. Sciadopitys (2 sp.): Japan.
Tribe Arthroiaxeae:
Genera: 9. Arthrotaxis (3 spp.): Tasmania.
10. Taiwania (1 sp.): North Burma, Yunnan, Taiwan.
No species of this family is endemic in India. But, Cryptomeria japonica (Fig. 728B), introduced into India from Japan in the nineteenth century has become strongly naturalised in Darjeeling as a dominant forest vegetation in the temperate zone. Locally known as dhupi, it is a source of lumber and fuel.
Family # 7. Cupressaceae:
Cupressaceae is another family of arborescent to shrubby conifers. The leaves are persistent, small, scale-like, opposite or in whorls. Male strobili are small; microsporophylls are somewhat peltate bearing 2 to 6 microsporangia. Female cones are on short branches bearing few scales; ovuliferous scales are flattened or peltate bearing 1 to 12 ovules.
Female cones are dry in Thuja, Cupressus, etc., but fused fleshy, berrylike in Juniperus, etc. There are 16 genera with about 133 species.
Subfamily Cupressoideae:
Genera: 1. Cupressus (Cypress—about 15 spp.): Eastern Mediterranean to Eastern Asia including China, Western Noth America, Central America. Widely cultivated (Fig. 729B).
2. Chemaecyparis (about 6 spp.): Japan, Taiwan, North America.
Subfamily Thujoideae:
Genera: 3. Thuja (6 spp.): East Asia, N. America. Widely cultivated as ornamental plant. Common species in Indian gardens— T. onentalis (Fig. 729A) and T. plicata. Known as fossil since Upper Cretaceous and Tertiary.
4. Thujopsis (1 sp.): Japan, Fossil from Tertiary Greenland.
5. Libocedrus (9 spp.): Burma, Molucca, China, Taiwan, New Guinea, Australia, Newzealand, New Caledonia, California, South America. Fossil in Tertiary Europe and N. America.
6. Pilgeodendron (1 sp.): Chili.
7. Callitris (20 spp.): Australia, Tasmania, New Caledonia. Fossil in Upper Cretaceous of Europe. Cultivated in Nilgiri Hills for essential oil and fuel. Introduced in 1886.
8. Neocallitropsis (1 sp.): New Caledonia.
9. Tetraclinis (1 sp.): Spain.
10. Actinostrobus (2 spp.): W. Australia.
11. Widdringtonia (5 spp.): S. Africa.
12. Fitzroya (1 sp.): Chili and Patagonia.
13. Diselma (1 sp.): Tasmania.
14. Fokienia (3 spp.): China.
Subfamily Juniperoideae:
Genera15. Arceuthos (1 sp.): Greece, Asia Minor’, Andes.
16. Juniperus (Juniper-60 spp.;: Asia, Europe, N. and C. Africa Alaska to C. America, West Indies. Widely cultivated (Fig. 730)’ Tertiary fossil Jurtiperoxylon common in Europe and N.-America.
Indian Species of Cupressaceae:
1. Cupressus torulosa D. Don.:
Outer ranges of Himalaya, Chamba to Nepal, Arunachal, Yunnan, 1800-2800 m. Up to 150 ft. tree. Timber very durable and easily workable, even better than deodar. Also used for pencil making (Fig. 729B). Several species of Cupressus, viz., C. funebris, C. cashmeriana (unknown in wild state—may be Tibetan in origin), C. sempervirens-are cultivated as ornamental plants.
2. Funiperus communis L. (—J. sibirica Burgod):
Western Himalaya up to Kumaon 1700-4300 m, spreading to Afghanistan, Persia, Siberia. Bushy to 12 m high tree. Fruits used in gin manufacture in Europe. Burnt as incense in the Punjab (Fig. 730A to E).
3. F. macropoda Boiss.:
Inner ranges of Western Himalaya up to Kumaon, Western Tibet, Baluchistan, 1500-4300 m. 1000 year old specimens with trunk 10 m in circumference are known from Lahul. 12-15 m high. Very suitable for pencil making (called ‘Himalayan pencil cedar’) but supply is inaccessible at present (Fig. 730F).
4. F. recurva Buch.-Ham.:
Temperate-alpine Himalaya 1700— 4600 m in the Inner ranges from Afghanistan to Bhutan, Upper Burma, China. May be a tree up to 10 m high but bushy in higher elevations.
5. F. squamata Buch. Ham.:
2400- 4300 m in the Himalaya with J. communis, Upper Burma, Afghanistan, China, Taiwan, Japan. A dense thicket.
6. F. wallichiana Hook f. ex Pari. (F. pseudosabina Hook, f.):
Temperate-alpine Himalaya from Kashmir to Bhutan 2800— 4600 m. Shrub in Western Himalaya, a tree up to 18 m high in Sikkim.
The distribution of the Indian species is shown in the map in Figure 731.
Family # 8. Araucariaceae:
A family of beautiful trees with branches in whorls. Leaves needle-like with single vein or broad with parallel veins, spiral or distichous. Male cones large, catkin-like. Microsporangia linear, hanging from peltate microsporophyll’s. Female cones woody, very large, with spiral scales in which the bract and the ovuliferous scale are completely fused in Ataucaria but are free in Agathis.
The morphology of the scale is disputed by some who think it is a simple sporophyll with a ligule. Each scale has a single ovule. The male gametophyte of Araucaria shows a prothallus tissue sometimes formed of about 40 cells (Fig. 732C) so that it is morphologically more primitive than even the living heterosporous Pteridophytes.
Predominantly a Southern Hemisphere family. The family is apparently very primitive. Upper Triassic Araucarioxylon wood is associated with the family.
Widespread Araucarites from Jurassic also belong here. Three species of Araucarites fossils are known from Indian Upper Gondwana Jurassic (Rajmahal and Jabalpur stages) viz., A. cutchensis, A. macropterus, A. latifohus. Fossil Agathis is known from the Northern Hemisphere during the Cretaceous.
There are two genera with about 35 species:
Tribe Agatheae:
Genus: 1. Agathis (Kauri pine— 20 spp.):
Cochin-China, Malay, East Indies, Philippines, Newzealand, Australia, Fiji, New Caledonia, New Hebrides. A valuable timber tree. Leaves broad with parallel veins.
Tribe Araucarieae:
Genus: 2. Araucaria (about 15 spp.):
New Guinea, East Australia, New Caledonia, South America. Timber as well as ornamental tree. Some species are grown in Indian parks, etc., viz., A. columnaris (—A. cookii), A. bidwilii, A. cuttninghamii (Fig. 732).
The two following families are often associated with the Taxaceae (placed here in a separate order Taxales) into a group Taxares (as opposed to the Pinares) because of the absence of obvious female cones in most genera:
Family # 9. Podocarpaceae:
Shrubs or trees with linear or lanceolate leaves. In Podocarpus the leaf is fairly broad with parallel veins. Dwarf shoots transformed into phylloclades in Phyllocladus. Male strobilus of microsporophylls each with two microsporargia. Pollens winged. Definite female cones in some species, in others it is very much reduced with two or even one scale laterally bearing a single ovule.
In addition, the ovule is covered by an outgrowth called epimatium (Fig. 733C & D) which is probably the ovuliferous scale though it has been supposed to be an all or a second integument. When ripe the epimatium as well as the stalk of the ovule (peduncle) become fleshy while the integument turns stony. The male gametophyte (Fig. 733E) resembles Araucaria but with fewer prothallial cells.
This is an ancient family with fossils clearly known up to Upper Triassic even in India. They may even be related to the Triassic-Jurassic Cheirolepidaceae (c.f. page 1079) in which an epimatium is present.
Podocarpaceae is mainly confined to the Southern Hemisphere but Podocarpus extends to India, China and Japan. There are 7 genera with about 111 species.
Subfamily Pherosphaeroideae:
Genus: 1. Pherosphaera (2 spp.): Tasmania.
Subfamily Phyllocladoideae:
Genus: 2. Phyllocladus (6 spp.): Borneo, Philippines, Newzealand, Tasmania, New Guinea (Fig. 733A).
Subfamily Podocarpoideae:
Genera: 3. Saxegothaea (1 sp.): Chili.
4. Microcachrys (I sp.): Tasmania.
5. Dacrydium (20 spp.): Newzealand, Australia, Chili.
6. Podocarpus (about 80 spp.):
As important in the Southern Hemisphere as Pinus in the North: Africa, India, Burma, Japan, East Indies, Australia, Newzealand, C. and S. America, West Indies (Fig. 733B to E).
7. Acmopyle (2 spp.): New Caledonia, Fiji.
Indian Species of Podocarpaceae:
1. Podocarpus nerifolius D. Don.:
Spreading from the plains (tropical evergreen climax forests) to 900 m in the Eastern Himalaya, Sikkim eastwards to Khasia, Chittagong, Burma, Andamans. The timber is of value and is used for oars, paddles, spears, masts, etc. (Fig. 733B to E).
2. P. wallichianus G. Presl. (—P. latifolia Wall.):
Assam, Burma, Western Ghats from Nilgiri southwards up to 1500 m, Nicobar Islands. Slightly aromatic. This is the only natural conifer in South India.
Distribution of these species is shown in the map in Figure 731.
Family # 10. Cephalotoxageae:
The family comes even nearer to Taxaceae and is often included within it. They are trees with opposite or whorled branches and distichous (spiral on vertical stems), linear, persistent leaves with midribs. The leaves and branches are covered with a white powder on the underside.
Male flowers in globose heads in leaf axils. Each microsporophyll with three microsporangia.
Female cones with several pairs of bracts each subtending two erect ovules (Fig. 734D). Usually one or two ovules mature into stalked drupaceous fruits in each cone (Fig. 734B). Cephalotaxus has a mesarch stem which is unique among conifers and causes its separation from the Taxaceae. Fossils (Cephalotaxopsis and Cephalotaxites) are known since the Cretaceous.
Only one genus is usually recognised:
Genus Cephalotaxus (6 spp.): Tropical Eastern Himalaya, Burma, Thailand, S. and M. China, Japan (Fig. 734).
Indian Species of Cephalotaxaceae:
1. Cephalotaxus manii Hook. f.: Khasia and Naga Hills. 1370- 2600 m (Fig. 734).
2. C. griffithii Hook f.: Arunachal, Naga Hills, Manipur, Mishmi Hills, Burma, 1520-1820 m.
Both the species are small trees but the timber does not seem to be of much use. Their distribution is shown in the map in Figure 731.
