A new species of spionid polychaete from the coastal waters of southwest India, Trochochaeta chakara sp. nov., is described and illustrated. Adults are common on Alappuzha mud banks (locally known as Chakara) off the coast of Kerala. They live in silty tubes in soft sediment and are characterized by the presence of two pairs of red eyes, caruncle extending to end of chaetiger 1, heavy falcate spines in neuropodia of chaetigers 2 and 3 (those in chaetiger 3 much stronger and darker), capillary chaetae in notopodia of chaetigers 1, 3–10, frayed heavy spines in neuropodia of chaetigers 4–13, hirsute capillaries in neuropodia from chaetiger 14, lateral interneuropodial membranes from chaetiger 14, one pair of ventral papillae on each chaetiger from chaetigers 14–16, bundles of acicular spines in notopodia from chaetigers 50–52, and small pygidium with up to six pairs of short cirri. This is the third species of Trochochaeta described and found in the Indian Ocean, including T. orissae (Fauvel, 1932) and T. cirrifera (Hartman, 1975).

The white mullet, Mugil curema (Mugilidae), is a catadromous euryhaline fish with an omnivorous diet, and is distributed mainly along the Pacific and Atlantic coasts of the Americas. Mullets represent an important economic resource for the artisanal fisheries in Mexico. In this study, 73 individuals of M. curema were analysed; specimens were sampled in 4 coastal lagoons of the Yucatán Peninsula, Mexico, between 2022 and 2024. Parasite identification was accomplished by using DNA sequences. Nineteen parasite taxa were found, including 1 monopisthocotylan, 1 copepod, 1 acanthocephalan, 1 nematode, and 15 trematodes. Specimens were sequenced for a nuclear or mitochondrial molecular marker. Ten taxa are reported for the first time in this host species, including the adult trematodes Saccocoelioides olmecae; Schikhobalotrema sp. 1 and sp. 2, Hemiuridae gen. sp., the larval trematodes Mesostephanus microbursa, M. cubaensis, Cardiocephaloides medioconiger, Saccularina sp., Bucephalus sp., as well as the larval nematode Contracaecum fagerholmi. Of the 21 metazoan parasites recorded, 58% were adults and 42% were larval stages. The checklist of the metazoan parasites of M. curema was updated. Our study contributes to the understanding of the parasite diversity of an economically important fish species with a wide distribution range and corroborates the usefulness of combining morphological and molecular data for species identification and for linking larval forms with adults to complete parasite life cycles. Our results will be useful in further studies of parasites as bioindicators of ecosystem health, and studies of the role of parasites in food webs in coastal lagoons.

The first report of Ophiophragmus luetkeni occurred in the British Virgin Islands; however, it was also recorded in Brazil, the United States Virgin Islands, and Trinidad and Tobago, yet its occurrence in Colombia was previously lacking. Between 2023 and 2024, four specimens were collected from sandy and muddy substrates in Cispatá Bay, Colombian Caribbean. Taxonomic identification was conducted through morphological observations and microstructural analysis using Scanning Electron Microscopy. A comparative table for Ophiophragmus species recorded in Colombia are also provided. This new record increases the number of Ophiophragmus species in Colombia to three, contributing to the country’s marine biodiversity and expanding the knowledge of O. luetkeni distribution.

The English past tense contains pockets of variation, where regular and irregular forms compete (e.g. learned/learnt, weaved/wove). Individuals vary considerably in the degree to which they prefer irregular forms. This article examines the degree to which individuals may converge on their regularization patterns and preferences. We report on a novel experimental methodology, using a cooperative game involving nonce verbs. Analysis of participants' postgame responses indicates that their behavior shifted in response to an automated co-player's preferences, on two dimensions. First, players regularize more after playing with peers with high regularization rates, and less after playing with peers with low regularization rates. Second, players' overall patterns of regularization are also affected by the particular distribution of (ir)regular forms produced by the peer.

We model the effects of the exposure on participants' morphological preferences, using both a rule-based model and an instance-based analogical model (Nosofsky 1988, Albright & Hayes 2003). Both models contribute separately and significantly to explaining participants' pre-exposure regularization processes. However, only the instance-based model captures the shift in preferences that arises after exposure to the peer. We argue that the results suggest an account of morphological convergence in which new word forms are stored in memory, and on-line generalizations are formed over these instances.

With regard to change in inflection, historical linguistics fundamentally relies on the concept of morphological analogy, which is held responsible for nearly all change not attributable to phonological factors. Despite its central importance, how morphological analogy operates has never been established. Two different opinions are held in contemporary linguistics. The first position assumes that morphological analogy modifies inherited inflectional forms, making them more similar to other inflectional forms. According to the second position, in the course of morphological analogy, inherited inflectional forms are not merely modified but rather are replaced by forms created entirely anew on a model pattern already present in the grammar. This research report tries to establish what kind of data may constitute the evidence sufficient to differentiate between the two views. It argues that all relevant data point to whole-word replacement as the only mechanism of analogical change in inflection.

As children learn their mother tongues, they make systematic errors. For example, English-speaking children regularly say mouses rather than mice. Because children's errors are not explicitly corrected, it has been argued that children could never learn to make the transition to adult language based on the evidence available to them, and thus that learning even simple aspects of grammar is logically impossible without recourse to innate, language-specific constraints. Here, we examine the role children's expectations play in language learning and present a model of plural noun learning that generates a surprising prediction: at a given point in learning, exposure to regular plurals (e.g. rats) can decrease children's tendency to overregularize irregular plurals (e.g. mouses). Intriguingly, the model predicts that the same exposure should have the opposite effect earlier in learning. Consistent with this, we show that testing memory for items with regular plural labels contributes to a decrease in irregular plural overregularization in six-year-olds, but to an increase in four-year-olds. Our model and results suggest that children's overregularization errors both arise and resolve themselves as a consequence of the distribution of error in the linguistic environment, and that far from presenting a logical puzzle for learning, they are inevitable consequences of it.

In Amuzgo (Eastern Otomanguean), the formation of nominal plurals exhibits many realizations, ranging from the simple addition of a nasal prefix (/n-tɛ2/ ‘PL-priesť → [ntɛ2]), to additional initial consonant fortition (/n-sa1/ ‘PL-elote’ → [ntsa1]; /n-ʦəiʔ3/ ‘PL-egg’ → [ntəiʔ3]; /n-ʃo²ʧi2/ ‘PL-griddle’ → [ŋko²ʧi2t]). initial consonant deletion (/n-ʧəm?2/ ‘PL-papeť → [ɲəm?2]), and sometimes also the replacement of the prefixai nasal by a lateral (/n-tsjo3/ ‘PL-bottle’ → [Ijo3]). In this paper, we argue that all of the changes above follow from two main principles: (1) The underlying contrast between the two pairs of phonemes characterized by a delayed release - the [+anterior] /s, ts/ and the [-anterior] /ʃ, ʧ/ - must be maintained; and (2) /s, ʃ/ cannot be faithfully realized after [n]. These principles, in interaction with other considerations, lead to an establishment of a push chain (/s/→/ts/→/t/) among [+anterior] consonants and to a case of saltation (/tʃ/→tʃ/; /ʃ/→/k/) among [-anterior] consonants.

Infixation and allomorphy have long been investigated as independent phenomena—see, for example, Ultan 1975, Moravcsik 1977, and Yu 2007 on infixation, and Carstairs 1987, Paster 2006, Veselinova 2006, and Bobaljik 2012 on allomorphy. But relatively little is known about what happens when infixation and allomorphy coincide. This article presents the results of the first crosslinguistic study of allomorphy involving infixation, considering fifty-one case studies from forty-two languages (fifteen language families). Allomorphy and infixation interact systematically, with distinct sets of behaviors characterizing suppletive and nonsuppletive allomorphy involving an infix. Perhaps most notably, suppletive allomorphy is conditioned only at/from the stem edge, while nonsuppletive allomorphy is conditioned only in the surface (infixed) environment. The robustness of these and related findings supports a universal serial architecture of the morphosyntax-phonology interface where: (i) infixation is indirect, involving displacement from a stem-edge position to a stem-internal one, counter to several influential theories of infixation (see especially McCarthy & Prince 1993a and Yu 2007); (ii) suppletive exponent choice is prior to (i.e. not regulated by) the phonological grammar (in line with Paster 2006, Pak 2016, Kalin 2020, Rolle 2021, and Stanton 2023, inter alia); and (iii) realization—including exponent choice and infixation—proceeds from the bottom of the morphosyntactic structure upward (à la Bobaljik 2000, Embick 2010, Myler 2017).

Play languages (also known as language games or ludlings) represent a special type of language use that is well known to shed useful light on linguistic structure. This paper explores a syllable transposition play language in Zenzontepec Chatino that provides evidence for the segmental inventory, syllable structure, the limits of the phonological word, the prosodic status of inflectional formatives, and the autonomy of tone, all of which aligns with independent phonological evidence in the language. While recent theoretical and cross-linguistic studies have questioned the nature, and even the validity, of constituents such as the phonological word, the syllable, and the onset, this study provides an example of a language with strongly manifested phonological constituents. Following the International Year of Indigenous Languages, the study also highlights the importance of in-depth analysis of less-studied languages for linguistic theory, typology, and language maintenance or reclamation for communities.

Prefixes and suffixes display distinctive linguistic behaviors. Not only does a crosslinguistic asymmetry exist between them in terms of structural properties, combinatorial constraints, and frequency, but there is also extensive evidence that prefixes and suffixes are processed differently. To further investigate the differences in how prefixes and suffixes are processed, we conducted five crossmodal priming experiments in Bengali, a language rich in derivational morphology. Although all combinations of stems, prefixes, and suffixes provided facilitation, we found that stems primed related prefixed forms to a greater degree than they primed related suffixed forms. Furthermore, morphologically related prefixed forms primed other prefixed forms more than suffixed forms primed related suffixed forms. On the basis of these findings, we propose that the asymmetry in how prefixes and suffixes are processed is due not only to differences in perception, reading, and inhibition from the phonological cohort, but also to the salience of the morpheme boundaries in affixed word representations during recognition.

This article investigates how children learn an infinitely expanding ‘universal’ system of classificatory kinship terms. We report on a series of experiments designed to elicit acquisitional data on (i) nominal kinterms and (ii) sibling-inflected polysynthetic morphology in the Australian language Murrinhpatha. Photographs of the participants' own relatives are used as stimuli to assess knowledge of kinterms, kin-based grammatical contrasts, and kinship principles, across different age groups. The results show that genealogically distant kin are more difficult to classify than close kin, that children's comprehension and production of kinterms are streamlined by abstract merging principles, and that sibling-inflection is learned in tandem with number and person marking in the verbal morphology, although it is not fully mastered until mid to late childhood. We discuss how the unlimited nature of Australian kinship systems presents unusual challenges to the language learner, but suggest that, as everywhere, patterns of language acquisition are closely intertwined with children's experience of their sociocultural environment.

This article argues that language play is intimately related to linguistic variation and change. Using two corpora of online present-day English, we investigate playful conversion of adjectives into abstract nouns (e.g. made of awesome∅), uncovering consistent rule-governed patterning in the grammatical constraints in spite of this option stemming from deliberate subversion of standard overt suffixation. Building on Haspelmath's (1999) notion of ‘extravagance’ as one of the keys to language change, we account for the systematic patterning of deliberate linguistic subversion by appealing to tension between the need to stand out and the need to remain intelligible. While we do not claim that language play is the only cause of linguistic change, our findings position language play as a constant source of new linguistic variants in very large numbers, a small proportion of which endure as changes. Our conclusion is that language play goes a long way toward accounting for linguistic innovations—with respect to where they come from and why languages change at all.

Using novel data from Kipsigis (Southern Nilotic; Kenya), we present the first attested case of across-the-board paradigmatic tonal polarity. The nominative case forms of nominal modifiers (adjectives, possessives, and demonstratives) are segmentally identical to their oblique case counterparts but have the opposite tonal pattern across the board: nominative and oblique modifiers differ in not just one but EVERY tonal specification. Kipsigis polarity thus results in maximal tonal contrast between two morphologically related words. We show how the Kipsigis pattern may be captured in an item-and-process theory of morphology with dedicated exchange mechanisms and in an item-and-arrangement theory that allows for morpheme-specific phonology; we suggest that an item-and-process approach may provide a more straightforward account.

Language-contact studies have shown that the transfer of morphology from one language to another is relatively rare (Gardani 2008, Grant 2012, Matras 2015), and the copying of verbal inflectional morphology is particularly infrequent (Seifart 2017). Copied morphemes are frequently assumed to enter the recipient language via ‘indirect affix borrowing’, whereby complex lexemes are copied and subsequently analyzed into their component parts in the recipient language, thus enabling use of the copied affixes with native roots (Grant 2012, Seifart 2015, Evans 2016). Although ‘direct affix borrowing’, in which speakers of the recipient language identify the meaning of affixes in the model language and transfer them directly for use with native roots, is known to occur, it has until now been identified only for derivational morphemes (Seifart 2015). I here provide evidence that inflectional morphemes, namely four Sakha (Yakut) tense-aspect-mood markers plus associated subject agreement paradigms, were copied directly into the Lamunkhin dialect of Even by fully bilingual speakers. This argument is based on the absence of Sakha verbal roots found with these paradigms in a corpus of Lamunkhin Even recordings, as well as on patterns of cooccurrence of these morphemes in clauses with Even grammatical morphology.

In a number of signed languages, the distinction between nouns and verbs is evident in the morphophonology of the signs themselves. Here we use a novel elicitation paradigm to investigate the systematicity, emergence, and development of the noun-verb distinction (qua objects vs. actions) in an established sign language, American Sign Language (ASL), an emerging sign language, Nicaraguan Sign Language (NSL), and in the precursor to NSL, Nicaraguan homesigns. We show that a distinction between nouns and verbs is marked (by utterance position and movement size) and thus present in all groups—even homesigners, who have invented their systems without a conventional language model. However, there is also evidence of emerging crosslinguistic variation in whether a base hand is used to mark the noun-verb contrast. Finally, variation in how movement repetition and base hand are used across Nicaraguan groups offers insight into the pressures that influence the development of a linguistic system. Specifically, early signers of NSL use movement repetition and base hand in ways similar to homesigners but different from signers who entered the NSL community more recently, suggesting that intergenerational transmission to new learners (not just sharing a language with a community) plays a key role in the development of these devices. These results bear not only on the importance of the noun-verb distinction in human communication, but also on how this distinction emerges and develops in a new (sign) language.