Languages are replete with cases of lexical allomorphy. Their characteristic property is that the distribution of allomorphs is explicable on general phonological grounds, but no actual phonological rule exists in the grammar of the language that would derive both from the same underlying representation. In this note, we take up the two cases mentioned above, the historically matured allomorphy of the Latin noun-forming endings and the newly emerging allomorphy of the plurality marker in Japanese loanwords. From a variety of evidence characterized as 'prosodic trapping', Mester 1994 argues that the optimal foot structure of Latin is the bimoraic balanced trochee, ('LL) (two light syllables) or ('H) (one heavy syllable). Crucially, in a quantitative system, the unbalanced ('HL) and ('LH) do not qualify as trochees, and neither does ('L). In this restricted foot inventory, light syllables are often prosodically trapped initially: #L(H)..., and medially between heavy syllables: ...(H)L(H)....

I argue that there exists a class of phonological phenomenon that, while naturally expressed in parallel OT, remain recalcitrant in the serial instantiation of OT, Harmonic Serialism. The primary case study comes from Mohawk. In Mohawk, the typical foot is a disyllabic, monosyllable. Wherever the canonical stress position, the penult, is open, vowel lengthening occurs to supply the second mora. However, when a separate constraint against long epenthetic vowels blocks lengthening, a disyllabic foot emerges instead. This conspiracy on Mohawk foot structure cannot be derived in Harmonic Serialism, because the constraint driving the conspiracy, FootBinarity, must be demoted, in the course of the derivation. I show that Mohawk is not an isolated case. Rather, the finer detail of Mohawk phonology can be abstracted away from and the sort of interaction Harmonic Serialism cannot derive turns out to be defineable in terms of abstract constraints and rankings. I also show attested cases from nasal spreading and assimilation that meet this abstract schema, and that they cannot be derived in HS. Thus, parallelism is a must to express conspiracy within violable constraint-based frameworks.

In Japanese native phonology, geminate consonants are contrastive (as in [kata] ‘shoulder’ vs. [katta] ‘win-PAST’), but geminates in loanwords can have differing sources and motivations (see Kubozono, Itô, Mester 2009, Kawagoe 2015, and references cited therein): we see gemination of singletons in loanwords from English, in which consonant length is not distinctive ([kæt] E ng ‘cat’ > [kjatto] Jp ), whereas we see geminate-preservation in loanwords from Italian ([espresso] It ‘espresso’ > [esupuresso] Jp), in which the length of most consonants is contrastive. In loanwords from Italian, however, not all geminates are preserved. This research addresses the cases of degemination, and captures the pattern as stress-based neutralization (Beckman 1998) of consonant length within the framework of Optimality Theory (Prince & Smolensky 1993). Through a database built from dictionaries and a nonce-adaptation survey conducted online, it confirms the preference towards geminates in penultimate position and the ban against geminates in other positions, especially for liquid geminates.