Chaetothyrina musarum (Speg.) Theiss., Annls

Singtripop, Chonticha, Hongsanan, Sinang, Li, Junfu, Silva, Nimali Indeewari De, Phillips, Alan J. L., Jones, E. B. Gareth, Bahkali, Ali H. & Hyde, Kevin D., 2016, Chaetothyrina mangiferae sp. nov., a new species of Chaetothyrina, Phytotaxa 255 (1), pp. 21-33 : 25-28

Chaetothyrina musarum (Speg.) Theiss., Annls mycol. 11(6): 495 (1913)

≡ Chaetothyrium musarum Speg., Anales del Museo Nacional de Historia Natural Buenos Aires 6: 297 (1898).

Description from BPI 646466 ( Fig 2 .)

Epiphytic on the surface of fruit of Musa sapientum L. Sexual morph: Thyriothecia 110–155 × 105–150 μm (x = 134 × 123 μm, n = 5), superficial on host tissues, solitary, circular, brown to dark brown, rounded and darkened at the margin, easily removed, base poorly developed, with setae, ostiole central, lacking superficial mycelium. Setae 90−120 μm long, arising from the surface of thyriothecia, straight, rounded at the apex, unbranched, septate, darkened at the septa, brown to dark brown. Upper wall comprising 2−3 layers of textura epidermoidea, brown to dark brown. Hamathecium comprising septate, hyaline, pseudoparaphyses. Asci 24–38 × 10–14 μm (x = 32 × 12 μm, n = 8), 8-spored, bitunicate, broadly obovoid to pyriform, apex apically rounded, with an ocular chamber, smooth-walled. Ascospores 10–13 × 3–4 μm (x = 12 × 4 μm, n = 20), 2–3-seriate, hyaline, broadly ellipsoidal to fusoid, 1-septate, slightly constricted at the septum, upper cell mostly larger than lower cell, basal cell with rounded ends, smooth-walled.

Material examined:— BRAZIL. Districto Federal: on fruit of Musa sapientum L., 30 December 1931, H. Grillo ( BPI 646466).

Notes:— Chaetothyrina musarum was introduced by Theissen (1913) as a monotypic genus, and Chaetothyrium musarum Speg. (1899) and Plochmopeltidella smilasina Mendoza (1925) are synonyms. The fungus is reported from Musa sp. , Musa paradisiaca L. ( Musaceae ), Smilax spp. ( Liliaceae ) and other plants in tropical America, Africa and South Asia ( Müller & von Arx 1962).

Description from reference collection ( Fig. 3 )

Faceoffungi Number: FoF02009

Epiphytic associated with sooty blotch and flyspeck complex disease on the surface of fruit of Musa sp. , appearing as very small, black, shiny dots, rounded to ovoid, with setae. Sexual morph: Thyriothecia 125–160 × 125–150 μm (x = 140 × 138 μm, n = 5), superficial or partly immersed in host tissues, solitary, circular, brown to dark brown, rounded and darkened at the margin, easily removed, base poorly developed, with long setae, ostiole central, lacking superficial mycelium. Setae 105−135μm long, arising from the surface of thyriothecium, straight, rounded at the apex, unbranched, septate, darkened at the septa, brown to dark brown, smooth-walled. Upper wall comprising 2−3 layers of brown to dark brown cells of textura epidermoidea. Hamathecium comprising 1−1.8 μm wide, septate, hyaline pseudoparaphyses. Asci 30–41 × 10–13 μm (x = 35 × 12 μm, n = 10), 8-spored, bitunicate, broadly obovoid to pyriform, apically rounded, with an ocular chamber. Ascospores 11–14 × 4–5 μm (x = 12 × 4 μm, n = 20), 2–3-seriate, hyaline, broadly ellipsoidal to fusoid, somewhat curved, 1-septate, slightly constricted at the septum, smooth-walled, upper cell mostly larger than lower cell, base with rounded end. Asexual morph: Undetermined.

Culture characters: — Ascospores germinating on MEA at 25–28 oC after 24–36 hours, germ tubes appearing from each end of the ascospore, colonies reaching 1.8–2 cm diam. after 15 days on MEA at 25–28 oC, raised, comprising raised, dark grey mycelium, white to greyish at the margin, surface of colonies velvety.

Material examined:— THAILAND. Chiang Rai Province: Tar Sud District, on fruit of Musa sp. ( M. acuminata × M. balbisiana , Musaceae ), 12 January 2014, Chonticha Singtripop, FS02, ( MFLU 16-0884, HKAS 90976, reference specimen designated here); Chiang Rai Province:Tar Sud District, on fruit of Musa sp. ( M. acuminata × M. balbisiana ) 22 February 2015, Chonticha Singtripop, ( MFLU 16-0885), living culture, MFLUCC 15-0383, MUCL 55904.

Figures

FIGURE 2. Chaetothyrina musarum (BPI 646466). A. Specimen label. B. Herbarium specimens. C. Appearance of thyriothecia on host. D. Thyriothecia when viewed in squash mount. E. Section through thyriothecium. F. Seta arising from the surface of thyriothecium. G. Upper wall of thyriothecium when viewed in squash mount. h, i. Immature asci. j, k. Ascospores. Scale bars: d=50 μm, e=100 μm, f−i=10 μm, j, k=5 μm.

FIGURE 3. Chaetothyrina musarum (MFLU16-0884) a. Disease symptom on fruit. b, c. Appearance of thyriothecia on host. d. Section through thyriothecium. e. Thyriothecium when viewed in squash mount. f. Seta arising from the surface of thyriothecium. g. Upper wall of thyriothecium when viewed in squash mount. h. Pseudoparaphyses. i. Immature ascus. j–l. Mature asci. m–p.Ascospores. q. Colonies on MEA from above and below. Scale bars: b=500 μm, c=200 μm, d=50 μm, e=100 μm, f–l=20 μm, m–p=10 μm, q=2 cm.