02944nas a2200193   4500008004100000245014000041210006900181300001000250490000800260520215100268653001802419653002902437653004402466653002302510653003002533100002202563700002002585856014502605       2015                        eng d00aTemnothorax crasecundus sp. n. – a cryptic Eurocaucasian ant species (Hymenoptera, Formicidae) discovered by Nest Centroid Clustering0 aTemnothorax crasecundus sp n a cryptic Eurocaucasian ant species  a37-640 v4793 a<p>The paper integrates two independent studies of numeric morphology-based alpha-taxonomy of the cryptic ant species Temnothorax crassispinus (Karavajev, 1926) and T. crasecundus sp. n. conducted by different investigators, using different equipment, considering different character combinations and evaluating different samples. Samples investigated included 603 individual workers from 203 nests &ndash; thereof 104 nest samples measured by Seifert and 99 by Cs&ouml;sz. The material originated from Europe, Asia Minor and Caucasia. There was a very strong interspecific overlap in any of the 29 shape characters recorded and subjective expert determination failed in many cases. Primary classification hypotheses were formed by the exploratory data analysis Nest Centroid (NC) clustering and corrected to final species hypotheses by an iterative linear discriminant analysis algorithm. The evaluation of Seifert&rsquo;s and Cs&ouml;sz&rsquo;s data sets arrived at fully congruent conclusions. NC-Ward and NC-K-means clustering disagreed from the final species hypothesis in only 1.9 and 1.9% of the samples in Seifert&rsquo;s data set and by 1.1 and 2.1% in Cs&ouml;sz&rsquo;s data set which is a strong argument for heterospecificity. The type series of T. crassispinus and T. crasecundus sp. n. were allocated to different clusters with p = 0.9851 and p = 0.9912 respectively. The type series of the junior synonym T. slavonicus (Seifert, 1995) was allocated to the T. crassispinus cluster with p = 0.9927. T. crasecundus sp. n. and T. crassispinus are parapatric species with a long contact zone stretching from the Peloponnisos peninsula across Bulgaria northeast to the southern Ukraine. There is no indication for occurrence of interspecifically mixed nests or intraspecific polymorphism. However, a significant reduction of interspecific morphological distance at sites with syntopic occurrence of both species indicates local hybridization. The results are discussed within the context of the Pragmatic Species Concept of Seifert (2014). The taxonomic description and a differential diagnosis of T. crasecundus sp. n. are given.</p>
10ahybridization10aintraspecific dimorphism10aNumeric morphology-based alpha-taxonomy10aparapatric species10aPragmatic Species Concept1 aSeifert, Bernhard1 aCsősz, Sándor  uhttps://formicidae-bg.myspecies.info/content/temnothorax-crasecundus-sp-n-%E2%80%93-cryptic-eurocaucasian-ant-species-hymenoptera-formicidae