Calocybella lohitha K. P. D. Latha & Manim., 2016

Deepna Latha, K. P., Anil Raj, K. N., Cherolil, Thushara, Sharafudheen, Shahina A. & Manimohan, Patinjareveettil, 2016, Three new species of Calocybella from India based on morphology and molecular phylogeny, Phytotaxa 255 (2), pp. 133-143 : 134-137

Calocybella lohitha K. P. D. Latha & Manim. , sp. nov. Figs. 1A–C , 2A–G

MycoBank MB 815576

Etymology:— lohitha (Sanskrit) , reddish; refers to the overall reddish color of the basidiomata of this species.

Diagnosis:—Differing from Calocybella pudica in having collybioid basidiomata that show no discoloration on bruising, a reddish pileus with a finely granular surface, dull red, intervenose lamellae with concolorous edges, a reddish or brownish gray stipe, acynophilous basidiospores with conspicuous warts under the SEM, hyphae of pileus trama with pale reddish brown or maroon plasmatic pigment and a distinctive ITS sequence (KU366465).

Holotype:— INDIA. Kerala State: Ernakulam District, Perumbavoor, Iringolkavu Scared Grove , 04 June 2013, K. P. Deepna Latha, DKP40 ( CAL 1288 ).

Description:— Basidiomata small, collybioid. Pileus 8–24 mm diam., somewhat campanulate with a small obtuse umbo when young, becoming almost plano-convex with a shallow depression around the umbo with age; surface initially grayish red (12E7/OAC460) all over, becoming dark red (12F6/OAC524) on umbo and brownish red (10C7, 10C8/OAC587, OAC588) towards the margin with age, weakly hygrophanous and becoming paler, not pellucidstriate, tacky when wet, glabrous to the naked eye, finely granulose under a lens; margin slightly incurved, crenate to somewhat wavy. Lamellae sinuate, intervenose, moderately crowded, dull red (9B3/OAC598), up to 2.5 mm wide, with lamellulae of 3–7 lengths; edge slightly crenate or wavy, concolorous with the sides. Stipe 30–50 × 1.5–3 mm, central, terete, equal or slightly tapering towards the apex, cartilaginous, fistulose; surface initially grayish red (10C4/ OAC589), becoming reddish gray (10B2/OAC594) or brownish gray (10C2/OAC584) with age, appressed-fibrillose all over; base slightly enlarged, with white basal mycelium. Context soft, up to 2 mm thick at the center of the pileus, dark red (12F8/OAC524). Odor and taste not distinctive.

Basidiospores 5.5–6 × 2–3 (5.95±0.15 × 2.65±0.43) μm, Q = 1.83–3.0, Qm = 2.31, oblong-ellipsoid to pip-shaped, with a fine verrucose ornamentation, thin- to slightly thick-walled (≤ 0.25 μm), acynophilous, inamyloid. Basidia 20–25 × 6.5–8 μm, clavate, hyaline, thin-walled, siderophilous, 4-spored; sterigmata up to 2 μm long. Lamella-edge fertile. Pleuro- and cheilocystidia absent. Lamellar trama subregular; hyphae 2–11 μm wide, thin-walled, hyaline, grayish violet in KOH, inamyloid. Pileus trama interwoven composed of two distinct regions; upper half made up of hyphae 8–14 μm wide, with a pale reddish brown to maroon plasmatic pigment, thin- to slightly thick-walled; lower half composed of hyphae 2–7 μm wide, thin- to slightly thick-walled, hyaline, grayish violet in KOH. Pileipellis a cutis composed of slightly gelatinized hyphae; hyphae 2–8 μm wide, thin- to slightly thick-walled, hyaline. Stipitipellis a cutis; hyphae 2–8 μm wide, hyaline, thin- to slightly thick-walled, inamyloid. Caulocystidia absent. Clamp connections observed on all hyphae.

Habitat:— scattered, on the ground, among decaying litter.

Geographical distribution range:—known only from the type locality in Kerala State, India.

Comments:— Calocybella pudica shares a few characters with C. lohitha such as a similar-sized pileus, moderately crowded lamellae, a fibrillose stipe, similar inamyloid basidiospores with verrucose ornamentation, siderophilous basidia, absence of pleuro-, cheilo- and caulocystidia, a slightly gelatinized, cutis-type pileipellis and clamped hyphae. However, C. pudica is distinguished from C. lohitha in having an orange to brownish orange pileus, orange yellow lamellae with paler edges, a pale yellow, finely pruinose stipe which is tapered towards the base, a mealy odor, cyanophilous basidiospores, hyphae of pileus trama lacking reddish brown or maroon plasmatic pigment and a different stipitipellis structure ( Vizzini et al. 2015). Calocybella babruka described below in this account differs from C. lohitha in having brown basidiomata with a slightly compressed stipe which is tapered towards the base, emarginate lamellae with small decurrent teeth, presence of occasional crassobasidia and a distinctive ITS sequence that showed only 85% sequence identity in a pairwise alignment with that of C. lohitha . Callocybella swetha , another species proposed in this account, differs from C. lohitha in having whitish basidiomata, smooth basidiospores, occasional occurrence of crassobasidia, a trichoderm-type pileipellis, and a cutis-type stipitipellis with flaring-out hyphae. Moreover, it has only 87% ITS sequence similarity in a pair wise alignment with that of C. lohitha .

Comparison of the newly generated ITS sequence of C. lohitha with those sequences available in the GenBank suggests that C. lohitha has distinct ITS sequence. BLASTn search using ITS sequence of C. lohitha (KU366465: 666 bp) showed C. pudica as the closest hit (KP858003) with 86 % identity and 0 e-value.

Figures

FIGURE 1. A–F: Basidiomata of the three new species of Calocybella. A–C. C. lohitha. D–E. C. babruka. F–G. C. swetha. Scale bars: A–G = 10 mm. Photos: A–E. By K.P.D. Latha; F–G. By K.N.A. Raj.

FIGURE 2.A–G:Calocybellalohitha (CAL1288,holotype).A.Basidiospores;B.Basidiospore underSEM.C;Basidium;D.Siderophilous basidium; E. Stipitipellis; F. Hyphal septum showing clamp connection; G. Pileipellis. Scale bars: A, C–G = 10 μm; B = 1 μm.