A Monograph of the Lichen Genus Parmelina Hale - Smithsonian ...

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14 SMITHSONIAN CONTRIBUTIONS TO BOTANY evolved over a long period. The P. galbina group, as mentioned above, forms the only exception to this rule. ILIorph formation has also been an important mode of speciation in section Parmelina. The fol- lowing parent morph-vegetative morph series are indisputable: P. consors-P. pilosa (sorediate), P. quercina-P. tiliacea (isidiate), and P. imrniscens-P. lindmanii (isidiate). Parmelina phlyctina and isidiate P. antillensis are extremely close but less clear-cut morphs. A large complex of species have been derived from now extinct parents in the P. dissecta-P. horrescens group, as illustrated in Figure 9. Like the P. subaurulenta group of section Mye- lochroa, the parent morphs of these numerous vegetative morphs are either extinct or have yet to be discovered. The remaining species in the genus appear to have no discernible interrelationships or morphs. These include P. endoleuca, P. enormis, P. expallida, P. heteroloba (part of the P. darnaziana series?), P. pruinata, P. sirnplicior, P. swinscowii, P. usambarensis, P. veisiformis, and P. wallichiana. Classification of Parmelina The taxon Lichen section Imbricaria was first proposed by Schreber (1791:767). He cited no species, only Squamaria Hoffmann, which is invalid as the later homonym of Squamah Ludwig (Phane- rogamae). Acharius (1794:250) adopted the name as a tribe of Lichen and included in it L. olivaceus L. and L. tiliaceus Hoffmann, as well as several other species now recognized as belonging to Hypogymnta, Parmeliopsis, Physcia, and Xanthoria. XIichaux (1803) raised the name to generic rank and cited one species, a lichen now called Anzia colpodes (Acharius) Stizenberger. Fries (1825:242) later trans- ferred it to Parmelia as Parmelia section Imbricaria, and Koerber (1855:68) used it at the generic rank, even though he realized that the name was a later homonym of Imbricaria Decandolle (Phaneroga- mae). Koerber and contemporary lichenologists placed many species that we now consider parme- lioid in Imbricaria, while at the same time using Parmelia for many species now placed in Physcia. After the delimitation of Parrnelia in a modern sense by authors such as Sluller and Nylander, Imbricaria was relegated to synonymy under it. Hale and Kurokawa (1964: 130) grouped the narrow- lobed, marginally ciliate Parrneliae in Parmelia subgenus Parmelia section Imbricaria (Schreber) E. Fries, and it is essentially this group that I have seg- regated as a distinct genus, Parmelina (Hale, 1974: 482). Parmelina is a rather heterogeneous assemblage of 47 species differing in lobe width, production of cilia, pigmentation, and rhizine branching. Two major groups can be recognized, one including those species lacking terpenes and one with terpene- containing species. They may be conveniently re- garded as sections. Section Parmelina Parmelia section Hypotrachyna subsection Myelolezica Asa- hina, 1952:74 [type-species: Purrnelina tiliacea (Hoffmann) Hale]. The species in this section are characterized by the lack of any triterpenes. Except for two species, P. immiscens and P. lindmanii, the medulla is white and unpigmented. Several internally homogeneous groups can be recognized. For example, the P. dissecta-P. horrescens group (Figure 9) includes seven species with very similar lobe configuration, abundant marginal cilia, and gyrophoric acid or the closely related “horrescens” unknown. Heavily white-niaculate P. consow, P. pilosa, and P. rnuelleri, having coarse, leathery thalli and thick, furcate marginal cilia, are obviously related. The predominantly European complex of species, P. qztcrcina-P. iiliacea-P. pastillifera, contains lecanoric acid and forms an easily recognized but isolated group. Parmelina antillensis and P. phlyctina, both unusual in containing norstictic acid, have no close relatives in the genus. Two other New World species, P. immiscens and P. lindmanii with a yellow medulla, form an isolated branch of this section. The species with salazinic acid, P. enormis, P. simplicior, P. swinscowii, P. usambarensis, P. versi- formis, and P. wallichiana, have little in common except their chemistry. Finally, the remaining species, P. endoleuca, P. expallida, P. heteioloba, P. jamesii, and P. pririnata, have no obvious common ancestry or affinities with other species in the section.
NUMBER 33 15 Progenitor I- Progenitor Progenitor (gyrophoric acid) (“horrescens” unkn.) P. horrescens IP. schindleri P. sirbfutiscens Progenitor ,(white Progenitor rnedullaj (isidiate) (lobulate) (pustulate) (yellow medulla) I P. spir ntosu (pustulate) r-l-l P. dissei.tu P. sputhulatu P. cryptochloru (isidiate) (lobulate-isidiate) (sorediate) FIGURE 9.-Hypothetical derivation of species in the Parmelina dissecta-P. horrescens group. hrot shoivn are P. damaziana, a presumptile nonisidiate, nonsorediate derivative of the “horrescens” progenitor, and P. melanochaetn, a possible relative of P. dissecta but derived from a different progenitor. Section Myelochroa (Asahina) Hale, new status Parmelia section Hypotrachyna subsection Myelochroa Asa- hina, 1952374 [type-species: Parmelina aurdenta (Tucker- man) Hale]. All of the species in this section contain zeorin and either leucotylin or leucotylic acid and asso- ciated terpenes, and all, excepting P. indica, produce varying amounts of the yellow-orange pigment secalonic acid A and possibly other, as yet, unidenti- fied pigments. This group is highly restricted to Asia, and the 17 species have very close affinities, in sharp contrast to section Parmelina. Two apparently unrelated groups are recognira- ble in the section. One, the P. galbina group (P. galbina, P. hayachinensis, P. metarevoluta, and P. ob- sessa), is characterized by galbinic acid in addition to leucotylin and secalonic acid A. The other group includes two closely related subgroups, the P. auru- lenta subgroup (P. aul-ulenta, P. degelii, P. irru- guns, and P. rhytidodes) with leucotylic acid, and the P. subazirulenta subgroup (P. amagiensis, P. crassata, P. denegans, P. entotheiochroa, P. leuco- tyliza, P. perisidzans, P. subauiulenta, and P. xan- tholepis) with leucotylin. Parmelina indica can probably be classified in the P. szi baurulenta subgroup although it has a small saxicolous thallus and lacks secalonic acid A. The affinities of Parmelina lie primarily with Parmotrema Alassalongo, a broader lobed, loosely attached, often ciliate genus (Hale, 1965). Palme- Zina, however, has a far less evolved chemistry, nar- rower adnate lobes, consistently small spores, and adnate or sessile, usually imperforate apothecia. Where soredia are produced, they are lamina1 rather than marginal in contrast to most Parmo- trema species. All in all, however, the apparent intergradation between broad-lobed Parmelinae and the smaller lobed species of Parmot?-emu, involving perhaps six or eight species, poses difficult problems in the correct generic identification of individual specimens and for the “lumper,” at least, raises questions on the distinctness of the two genera as circumscribed here. I do not expect that the prob- lem can be resolved to the satisfaction of all lichenologists, but the basic differences should become clearer as more collections are made in tropical
Page 1 and 2: SMITHSONIAN CONTRIBUTIONS TO BOTANY
Page 3: Contents Page Introduction . . . .
Page 6 and 7: 2 Morphology THALISIS STRLCTURE.-Pa
Page 8 and 9: 4 SMITHSONIAN CONTRIBUTIONS TO BOTA
Page 14 and 15: 10 S\IITHSONIAS CONTRIBUTIONS TO BO
Page 16 and 17: Jamaica: P. antillensis, P. dissect
Page 20 and 21: 16 SMITHSONIAN CONTRIBUTIONS TO BOT
Page 26 and 27: 22 SMITHSOSIAN CONTRIBUTIONS TO BOT
Page 28 and 29: 24 SSIITHSONIAN CONTRIBUTIONS TO BO
Page 36 and 37: nate, often becoming lobulate, cili
Page 48 and 49: 44 SSIITHSONIAX CONTRIBUTIONS TO BO
Page 50 and 51: 46 hand, occurs at higher elevation
Page 62 and 63: 58 S\iITHSOXI 4S CONTRIBUTIOSS TO B
Page 64: horrescens, 31 immiscens, 32 indica

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