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  1. Abstract

    The recognition and delineation of cryptic species remains a perplexing problem in systematics, evolution, and species delimitation. Once recognized as such, cryptic species complexes provide fertile ground for studying genetic divergence within the context of phenotypic and ecological divergence (or lack thereof). Herein we document the discovery of a new cryptic species of trapdoor spider,Promyrmekiaphila korematsuisp. nov. Using subgenomic data obtained via target enrichment, we document the phylogeography of the California endemic genusPromyrmekiaphilaand its constituent species, which also includesP. clathrataandP. winnemem. Based on these data we show a pattern of strong geographic structuring among populations but cannot entirely discount recent gene flow among populations that are parapatric, particularly for deeply diverged lineages withinP. clathrata. The genetic data, in addition to revealing a new undescribed species, also allude to a pattern of potential phenotypic differentiation where species likely come into close contact. Alternatively, phenotypic cohesion among genetically divergentP. clathratalineages suggests that some level of gene flow is ongoing or occurred in the recent past. Despite considerable field collection efforts over many years, additional sampling in potential zones of contact for both species and lineages is needed to completely resolve the dynamics of divergence inPromyrmekiaphilaat the population–species interface.

     
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  2. Although numerous programs exist in many institutions of higher education aimed at helping students from underrepresented groups achieve their goals of successfully graduating in a science, technology, mathematics, or engineering (STEM) field and moving on to the next educational level or a career, few are set up to support students across schools, from their entry into postsecondary education at the community college through the completion of their fouryear degree at a university and beyond. Furthermore, few programs are able to offer the full range of support that has been shown to be optimally effective toward promoting student success, as in, for example, the Building Engineering and Science Talent (BEST) model laid out by Chubin and Ward (2009). The reason for this is simple: rarely are the funds available from any given source to allow a program to provide all the supports students need. In this paper, we provide an example of how this problem was (at least partly) solved by the close interaction of two Louis Stokes Alliances for Minority Participation and an S-STEM program, working within the context of other support opportunities at three community colleges and one university in Northern New Jersey. The programs and the mechanisms through which they support students are described and preliminary data examining their impacts are presented. 
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    Free, publicly-accessible full text available April 1, 2024
  3. Planetary extinction of biodiversity underscores the need for taxonomy. Here, we scrutinize spider taxonomy over the last decade (2008–2018), compiling 2083 published accounts of newly described species. We evaluated what type of data were used to delineate species, whether data were made freely available, whether an explicit species hypothesis was stated, what types of media were used, the sample sizes, and the degree to which species constructs were integrative. The findings we report reveal that taxonomy remains largely descriptive, not integrative, and provides no explicit conceptual framework. Less than 4% of accounts explicitly stated a species concept and over one-third of all new species described were based on 1–2 specimens or only one sex. Only ~5% of studies made data freely available, and only ~14% of all newly described species employed more than one line of evidence, with molecular data used in ~6% of the studies. These same trends have been discovered in other animal groups, and therefore we find it logical that taxonomists face an uphill challenge when justifying the scientific rigor of their field and securing the needed resources. To move taxonomy forward, we make recommendations that, if implemented, will enhance its rigor, repeatability, and scientific standards. 
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