A review of the Pseudomyrmex ferrugineus and Pseudomyrmex goeldii species groups: acacia-ants and relatives (Hymenoptera: Formicidae)

The Pseudomyrmex ferrugineus group contains the Mesoamerican acacia-ants, an assemblage of species that inhabit and protect swollen-thorn acacias (Vachellia spp.). Recent phylogenetic studies have confirmed the existence of two generalist (dead twig-inhabiting) species that are embedded within the P. ferrugineus group. They are described here as P. evitus sp. nov. (occurring from Mexico to Costa Rica) and P. feralis sp. nov. (Guatemala). The morphological definition of the P. ferrugineus group is revised to incorporate additional variability in the worker and queen castes. The previous diagnosis of the males, based largely on features of the genitalia, requires little revision. Closely related to the P. ferrugineus group is a clade of five predominantly South American species, here designated and diagnosed as the P. goeldii group. The five species, P. goeldii (Forel), P. laevifrons Ward, P. micans sp. nov., P. obtusus sp. nov., and P. parvulus sp. nov., are characterized and illustrated. P. laevifrons and P. micans are closely related and difficult to distinguish, possibly reflecting incomplete isolation. Keys are provided for the identification of the species in both groups.

Exosporium monanthotaxis Piroz. (Fungi: Ascomycota: Pezizomycotina) from Biligirirangan Hills, southern India

The paper reports the fungus Exosporium monanthotaxis Piroz. on an unidentified dead twig from the forest floor of Biligirirangan Hills, Karnataka, India.

First Report of Phytophthora insolita and P. inflata on Rhododendron in Ohio

During August 2003, we conducted a statewide survey of rhododendrons to determine if Phytophthora ramorum was present in Ohio ornamental nurseries. In total, 240 samples were randomly collected in 12 nurseries throughout Ohio from rhododendrons showing foliar necrotic lesions and twig dieback symptoms. The samples yielded 51 Phytophthora spp. isolates on PARP-V8 agar. The internal transcribed spacer (ITS) region of all isolates was amplified using the universal primers ITS1 and ITS4 and was sequenced. Consensus sequences from sense and antisense were then blasted against the GenBank database, allowing for the identification to species of ˜80% of all isolates. These identifications, and the ˜20% unknowns, were confirmed using blind morphological tests on the basis of the following parameters: colony morphology; shape and dimensions of sporangia and type of papillae; dimensions of oogonia and oospores; type and position of antheridia; presence or absence of chlamydospores; presence or absence and morphology of hyphal swellings; and growth rate at 35°C according to the Revisited Tabular Key of the species of Phytophthora (1). No P. ramorum was detected among the isolates; however, P. cactorum, P. citricola, P. citrophthora, and P. nicotianae were detected. We also found two occurrences of P. inflata Caros & Tucker and one of P. insolita Ann & Ko. (P. inflata: e-value ≤e-179, identities ≥95%; P. insolita: e-value = 0.0; identities = 95%.) P. inflata was isolated from two tissue types, a dead twig and a necrotic leaf tip. P. insolita was isolated from a necrotic leaf tip. Identity of the two species was confirmed morphologically using the parameters listed above as well as the following measurements (N = 40; all in μm) (1): P. inflata - sporangia: 40 × 24 ([24 to 68] × [18 to 34]); oogonia: 34.6 (28 to 40); oospores: 30.8 (25 to 38); P. insolita - sporangia: 42 × 28 ([34 to 56] × [22 to 38]); oogonia: 32 (26 to 36); oospores: 26 (22 to 30). Koch's postulates were satisfied by inoculating two rhododendron plants (cvs. PJM and Nova Zembla) with the putative pathogens. On each plant, each of three leaves was pierced with a dissecting needle and was inoculated by placing a 0.5-cm-diameter plug of mycelium that was taken from the margin of a colony actively growing on PARP-V8 agar on the wound. The inoculum was retained using clear adhesive tape. A similar procedure was used for twigs. Controls consisted of inoculations with sterile PARP-V8 agar medium. Both cultures of P. inflata and P. insolita produced necrotic lesions in all inoculations on both tissue types within 1 week, and they were reisolated from the margins of lesions on PARP-V8. The lesion margin was at least 2 cm away from the inoculum plug in leaf inoculations and several centimeters in twig inoculations. To our knowledge, this is the first report of P. inflata and P. insolita occurring on rhododendron and the first time P. insolita has been reported outside of Southeast Asia where it has been recovered only from soil. Reference: (1) D. J. Stamps et al. Mycol. Pap. No. 162. CAB Int. Mycol. Inst. Wallingford, UK, 1990.

Ascodichaena rugosa. [Descriptions of Fungi and Bacteria].

A description is provided for Ascodichaena rugosa. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. DISEASE: Although generally not regarded as pathogenic, there are some indications that Ascodichaena rugosa can act as a parasite. An ultrastructural study (using German material on beech) showed that hyphae of the fungus were distributed solely in phellem cells; cell-to-cell invasion was effected by penetration hyphae, causing no extensive dissolution of the cork wall; finger-like hyphae in the most recently formed layer of cork cells were interpreted as haustoria, suggesting a parasitic relationship; areas of bark infected by the fungus showed increased production of cork cells (BUTIN & PARAMESWARAN, 1980). On oak, the fungus colonizes cork cells and parasitizes the last separated phellem cells by forming finger-like haustoria. A full description of this disease and symptoms was provided by BUTIN (1981a). HOSTS: Acer pseudoplatanus (bark), Carpinus betulus (bark), Castanea sativa (twig), Fagus grandifolia (bark), F. crenata (branch), F. orientalis, F. sylvatica (bark, branch, dead attached twig, dead fallen twig, living bark, living twig, root, trunk, wood), F. sp. (bark), Nothofagus pumilio (twig), Quercus ilex (bark), Q. petraea (bark, dead attached twig, dead fallen bark, dead fallen twig, dead twig, living twig), Q. pubescens (twig), Q. robur (bark, dead attached twig, dead fallen twig, living twig), Q. sessilis (dead attached twig), Q. suber (twig), Quercus sp. (attached wood, bark, branch, dead attached twig, dead fallen twig, living twig, trunk, twig). GEOGRAPHICAL DISTRIBUTION: ASIA: Pakistan, Japan. NORTH AMERICA: Canada (Ontario, Québec), USA (Kansas, Maine, New Hampshire, New York). SOUTH AMERICA: Chile. EUROPE: Austria, Finland, France, Republic of Georgia, Germany, Great Britain, Greece, Ireland, Italy, Poland, Slovak Republic, Sweden, Ukraine. TRANSMISSION: By snails, which graze the stromata, and excrete viable spores (BUTIN, 198la).