02472nas a2200169   4500008004100000245014600041210006900187490000700256520188100263100001502144700001702159700001502176700002302191700002002214700001602234856005202250       2015                        eng d00aThe first multi-gene phylogeny of the Macrostomorpha sheds light on the evolution of sexual and asexual reproduction in basal Platyhelminthes0 afirst multigene phylogeny of the Macrostomorpha sheds light on t0 v923 aThe Macrostomorpha—an early branching and species-rich clade of free-living flatworms—is attracting interest because it contains Macrostomum lignano, a versatile model organism increasingly used in evolutionary, developmental, and molecular biology. We elucidate the macrostomorphan molecular phylogeny inferred from both nuclear (18S and 28S rDNA) and mitochondrial (16S rDNA and COI) marker genes from 40 representatives. Although our phylogeny does not recover the Macrostomorpha as a statistically supported monophyletic grouping, it (i) confirms many taxa previously proposed based on morphological evidence, (ii) permits the first placement of many families and genera, and (iii) reveals a number of unexpected placements. Specifically, Myozona and Bradynectes are outside the three classic families (Macrostomidae, Microstomidae and Dolichomacrostomidae) and the asexually fissioning Myomacrostomum belongs to a new subfamily, the Myozonariinae nov. subfam. (Dolichomacrostomidae), rather than diverging early. While this represents the first evidence for asexuality among the Dolichomacrostomidae, we show that fissioning also occurs in another Myozonariinae, Myozonaria fissipara nov. sp. Together with the placement of the (also fissioning) Microstomidae, namely as the sister taxon of Dolichomacrostomidae, this suggests that fissioning is not basal within the Macrostomorpha, but rather restricted to the new taxon Dolichomicrostomida (Dolichomacrostomidae + Microstomidae). Furthermore, our phylogeny allows new insights into the evolution of the reproductive system, as ancestral state reconstructions reveal convergent evolution of gonads, and male and female genitalia. Finally, the convergent evolution of sperm storage organs in the female genitalia appears to be linked to the widespread occurrence of hypodermic insemination among the Macrostomorpha.1 aJanssen, T1 aVizoso, D, B1 aSchulte, G1 aLittlewood, D, T J1 aWaeschenbach, A1 aSchärer, L  uhttps://macrostomorpha.myspecies.info/node/470602155nas a2200169   4500008004100000245005400041210005400095300001400149490000800163520166700171100002001838700002301858700002001881700001501901700001701916856005201933       2011                        eng d00aMating behavior and the evolution of sperm design0 aMating behavior and the evolution of sperm design  a1490-14950 v1083 aSperm are the most diverse of all animal cell types, and much of the diversity in sperm design is thought to reflect adaptations to the highly variable conditions under which sperm function and compete to achieve fertilization. Recent work has shown that these conditions often evolve rapidly as a consequence of multiple mating, suggesting a role for sexual selection and sexual conflict in the evolution of sperm design. However, very little of the striking diversity in sperm design is understood functionally, particularly in internally fertilizing organisms. We use phylogenetic comparative analyses covering 16 species of the hermaphroditic flatworm genus Macrostomum to show that a complex sperm design is associated with reciprocal mating and that this complexity is lost secondarily when hypodermic insemination—sperm injection through the epidermis—evolves. Specifically, the complex sperm design, which includes stiff lateral bristles, is likely a male persistence trait associated with sexual conflicts over the fate of received ejaculates and linked to female resistance traits, namely an intriguing postcopulatory sucking behavior and a thickened epithelium of the sperm-receiving organ. Our results suggest that the interactions between sperm donor, sperm, and sperm recipient can change drastically when hypodermic insemination evolves, involving convergent evolution of a needle-like copulatory organ, a simpler sperm design, and a simpler female genital morphology. Our study documents that a shift in the mating behavior may alter fundamentally the conditions under which sperm compete and thereby lead to a drastic change in sperm design.1 aSchärer, Lukas1 aLittlewood, D, T J1 aWaeschenbach, A1 aYoshida, W1 aVizoso, D, B  uhttps://macrostomorpha.myspecies.info/node/470100513nam a2200157   4500008004100000245005100041210005100092260003100143300001000174520004100184653001600225100002400241700002300265700001500288856005200303       2001                        eng d00aPhylogenetic systematics of the Macrostomorpha0 aPhylogenetic systematics of the Macrostomorpha  aNew YorkbTaylor & Francis  a28-383 aDescribes:
New macrostomorphan Taxon10aMacrostomum1 aRieger, Reinhard, M1 aLittlewood, D, T J1 aBray, R, A  uhttps://macrostomorpha.myspecies.info/node/1239