The phylogenetic position of Hydrovatus Motschulsky: evidence from larval morphology of H. caraibus Sharp (Coleoptera: Dytiscidae: Hydroporinae)

2006 ◽  
Vol 37 (4) ◽  
pp. 419-432 ◽  
Author(s):  
Mariano Michat
Keyword(s):  
Cladistic Analysis ◽  
Sister Group ◽  
Instar Larva ◽  
Phylogenetic Position ◽  
Sister Group Relationship ◽  
Larval Morphology ◽  
First Instar ◽  
Basal Half ◽  
Relationship Of ◽  
First Time

AbstractThe phylogenetic position of Hydrovatus Motschulsky was investigated based on a cladistic analysis of 18 hydroporine taxa and 69 characters from larval morphology. For this purpose, the three larval instars of H. caraibus Sharp were described and illustrated for the first time, emphasizing the morphometry and chaetotaxy. The resulting cladogram supported a sister-group relationship of the tribes Hydrovatini and Hyphydrini, based on three unambiguous synapomorphies: the absence of pore ANh, the proximal insertion of seta LA8, and the abdominal segment VI sclerotized ventrally. The strong development of seta AB5 and the absence of pore PAj are other two potential synapomorphies for this clade. The tribe Vatellini was resolved as more closely related to members of Hydroporini than to Hyphydrini. However, the support obtained for this relationship was weak, since no unambiguous synapomorphies were discovered. Larvae of H. caraibus are characteristic within Hydroporinae in the absence of an occipital suture, the presence of a galea (secondarily derived according to this study), and the absence of setae LA3 and UR8 and pores PAm and PAo. First instar larva is also unique in that the egg bursters are basally placed on the frontoclypeus and the claws bear ventral spinulae on basal half.

The phylogenetic position of the tuatara, Sphenodon (Sphenodontida, Amniota), as indicated by cladistic analysis of the ultrastructure of spermatozoa

1992 ◽  
Vol 335 (1274) ◽  
pp. 207-219 ◽  
Keyword(s):  
Cladistic Analysis ◽  
Sister Group ◽  
Sister Taxon ◽  
Phylogenetic Position ◽  
Sister Group Relationship ◽  
Usual Concept ◽  
Cladistic Analyses ◽  
Relationship Of

Sphenodon has traditionally been regarded as a little changed survivor of the Permo-Triassic thecodont or eosuchian ‘stem reptiles’ but has alternatively been placed in the Lepidosauria as the plesiomorphic or even apomorphic sister-taxon of the squamates. A cladistic analysis of 16 characters from spermatozoal ultrastructure of Sphenodon and other amniotes unequivocally confirms its exceedingly primitive status. The analysis suggests that monotremes are the sister-group of birds; squamates form the sister-group of a bird + monotreme clade while the three sister-groups successively below the bird + monotreme + squa- mate assemblage are the caiman, the tuatara and the outgroup (turtles). The monotreme + bird couplet, supports the concept of the Haemothermia, but can only be regarded heuristically. The usual concept of mammals as a synapsid-derived outgroup of all other extant amniotes is not substantiated spermatologically. All cladistic analyses made, and a separate consideration of apomorphies, indicate that Sphenodon is spermatologically the most primitive amniote, excepting the Chelonia. It is advanced (apomorphic) for the amniotes in only two of the 16 spermatozoal characters considered. A close, sister-group relationship of Sphenodon with squamates is not endorsed.

Phylogenetic relationships, larval morphology, and chaetotaxy of the subfamily Coptotominae (Coleoptera: Dytiscidae)

2013 ◽  
Vol 145 (3) ◽  
pp. 247-264 ◽  
Author(s):  
Mariano C. Michat ◽  
Yves Alarie
Keyword(s):  
Phylogenetic Relationships ◽  
Abdominal Segment ◽  
Cladistic Analysis ◽  
Sister Group ◽  
Sister Group Relationship ◽  
Larval Morphology ◽  
First Instar ◽  
Segment Viii ◽  
Tracheal Gills

AbstractLarval morphology of the monogeneric subfamily Coptotominae (Coleoptera: Dytiscidae) is described and illustrated in detail, with particular emphasis on morphometry and chaetotaxy. Larvae ofCoptotomusSay are unique within Dytiscidae in the presence of tracheal gills on the abdominal segments I–VI, a short bifid horn or nasale in instar I, long spinulae on the urogomphus in instar I, and rows of natatory setae on both the internal and external margins of the urogomphus in instars II and III. A cladistic analysis based on 125 larval characters sampled among representatives of other dytiscid subfamilies supports a sister-group relationship between Coptotominae and Laccophilinae based on the shared absence of setae LA10 and LA12 on the second labial palpomere and of pore ABc on the abdominal segment VIII. The clade Coptotominae + Laccophilinae resolved as sister to Lancetinae, all three subfamilies sharing the presence of an unusually low number of lamellae clypeales in the first instar (a condition called four-peg-pattern), postulated to have evolved secondarily within Dytiscidae.

scholarly journals First instar larvae of endemic Australian Miltogramminae (Diptera: Sarcophagidae)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Krzysztof Szpila ◽  
Kinga Walczak ◽  
Nikolas P. Johnston ◽  
Thomas Pape ◽  
James F. Wallman
Keyword(s):  
Laser Scanning ◽  
Instar Larva ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Maxillary Palpus ◽  
Larval Morphology ◽  
First Instar ◽  
Morphological Differences ◽  
Thoracic And Abdominal ◽  
First Time

AbstractThe first instar larva of a species of the Australian endemic genus Aenigmetopia Malloch is described for the first time, along with the first instar larvae of three other Australian species representing the genera Amobia Robineau-Desvoidy and Protomiltogramma Townsend. Larval morphology was analysed using a combination of light microscopy, confocal laser scanning microscopy and scanning electron microscopy. The following morphological structures are documented: pseudocephalon, antennal complex, maxillary palpus, facial mask, modifications of thoracic and abdominal segments, anal region, spiracular field, posterior spiracles and details of the cephaloskeleton. Substantial morphological differences are observed between the three genera, most notably in the labrum and mouthhooks of the cephaloskeleton, sensory organs of the pseudocephalon, spinulation, sculpture of the integument and form of the spiracular field. The first instar larval morphology of Aenigmetopia amissa Johnston, Wallman, Szpila & Pape corroborates the close phylogenetic affinity of Aenigmetopia Malloch with Metopia Meigen, inferred from recent molecular analysis. The larval morphology of Amobia auriceps (Baranov), Protomiltogramma cincta Townsend and Protomiltogramma plebeia Malloch is mostly congruent with the morphology of Palaearctic representatives of both genera.

The phylogenetic relationships of the two-winged South American Leptophlebiidae genera revisited with first description of the male imago of Bessierus Thomas & Orth (Insecta: Ephemeroptera)

Zootaxa ◽  
2019 ◽  
Vol 4674 (3) ◽  
pp. 375-385
Author(s):  
EDUARDO DOMÍNGUEZ ◽  
MARÍA GABRIELA CUEZZO ◽  
SIMÓN CLAVIER
Keyword(s):  
Sister Group ◽  
Sister Group Relationship ◽  
South American ◽  
Phylogenetic Hypothesis ◽  
New Information ◽  
Statistical Support ◽  
The Stability ◽  
New Diagnosis ◽  
Relationship Of ◽  
First Time

Four of the 43 genera of South American Leptophlebiidae are dipterous. A previous phylogenetic hypothesis supported that clade Askola+Hagenulopsis, and that Bessierus+Perissophlebiodes, are sister groups of the Farrodes complex. Adults of Bessierus and Perissophlebiodes were not known but posteriorly Perissophlebiodes male imago was described. Here, we describe the male imago of Bessierus for the first time. Both genera share, besides the absence of the hind wings, the asymmetrical fork of MA, symmetrical fork of MP, dissimilar tarsal claws, and forceps sockets fused. Along with the description of the imago, a new diagnosis for the genus Bessierus is presented, also updating the identification key with this new information. A new cladistics analysis is performed to test the stability of the proposed relationships of these four genera within Leptophlebiidae. We obtained a single cladistic hypothesis where the addition of Bessierus adult characters resulted in new synapomorphies for the (Bessierus, Perissophlebiodes) clade, and improved its clade statistical support. The fused forceps sockets resulted in a synapomorphy uniting Bessierus, Perissophlebiodes and Simothraulopsis. As a result of this new analysis, the hypothesis of independent losses of the hind wings in the two dipterous groups studied is supported. The Farrodes lineage is not supported as proposed in previous studies, being restricted only to (Farrodes (Simothraulopsis, Homothraulus)) while the identity of “Perissophlebiodes lineage” is supported. The sister group relationship of Rondophlebia is not clearly defined. 

Paraphyly of Chinese Amolops (Anura, Ranidae) and phylogenetic position of the rare Chinese frog, Amolops tormotus

Zootaxa ◽  
2007 ◽  
Vol 1531 (1) ◽  
pp. 49-55 ◽  
Author(s):  
HONG-XIA CAI ◽  
JING CHE ◽  
JUN-FENG PANG ◽  
ER-MI ZHAO ◽  
YA-PING ZHANG
Keyword(s):  
Morphological Characteristics ◽  
Sister Group ◽  
Phylogenetic Position ◽  
12S Rrna ◽  
Sister Group Relationship ◽  
Likelihood Methods ◽  
New Classification ◽  
Maximum Likelihood Methods ◽  
Species Groups ◽  
Relationship Of

In order to evaluate the five species groups of Chinese Amolops based on morphological characteristics, and to clarify the phylogenetic position of the concave-eared torrent frog Amolops tormotus, we investigated the phylogeny of Amolops by maximum parsimony, Bayesian Inference, and maximum likelihood methods using two mitochondrial DNA fragments (12S rRNA, 16S rRNA). Our results supported a sister group relationship of Amolops ricketti and Amolops hainanensis. However, the grouping of Amolops mantzorum and Amolops monticola needs to be resolved with more data. Amolops tormotus was nested in genus Odorrana. Thus, recognition of the A. tormotus group is unwarranted and A. tormotus should be referred to genus Odorrana as O. tormota. This species is the sister group of O. nasica plus O. versabilis. The new classification implies that the genus Wurana is to be considered as junior subjective synonym of Odorrana.

DESCRIPTION OF THE LARVAE OF ELEVEN NEARCTIC SPECIES OF HYGROTUS STEPHENS (COLEOPTERA: DYTISCIDAE: HYDROPORINAE) WITH AN ANALYSIS OF THEIR PHYLETIC RELATIONSHIPS

1990 ◽  
Vol 122 (5) ◽  
pp. 985-1035 ◽  
Author(s):  
Y. Alarie ◽  
P.P. Harper ◽  
R.E. Roughley
Keyword(s):  
Abdominal Segment ◽  
Cladistic Analysis ◽  
Sister Group ◽  
Structural Features ◽  
Sister Group Relationship ◽  
Larval Morphology ◽  
Systematic Analysis ◽  
Third Instar Larvae

AbstractA systematic analysis of larvae of 11 Nearctic species of Hygrotus Stephens was undertaken. The larvae are described and characterized; a key for their discrimination and illustrations of structural features of representatives of first- and third-instar larvae are provided. Many structural features, especially detailed variations in the chaetotaxy of cephalic capsule, head appendages, legs, last abdominal segment, and urogomphi, were found to be useful for systematic and phylogenetic comparisons. Based on 21 larval characters, a cladistic analysis of the species studied was developed. A sister-group relationship between H. laccophilinus (LeConte) and the remaining available species is suggested. The less derived species, i.e. those without natatory setae on the legs, appear phylogenetically more closely related to the larvae of Hydroporus s.str. Hygrotus masculinus (Crotch) is the most derived species of the genus and, for many characters, seems more closely related to Hyphydrini. According to larval morphology, it is hypothesized that the genus Hygrotus diverged posteriorly to the genus Hydroporus Clairville.

A phylogeny of Plesiosauria (Sauropterygia) and its bearing on the systematic status of Leptocleidus Andrews, 1922

Zootaxa ◽  
2008 ◽  
Vol 1863 (1) ◽  
pp. 1 ◽  
Author(s):  
PATRICK S. DRUCKENMILLER ◽  
ANTHONY P. RUSSELL
Keyword(s):  
Late Jurassic ◽  
Cladistic Analysis ◽  
Sister Group ◽  
Phylogenetic Position ◽  
Sister Group Relationship ◽  
New Taxon ◽  
Short Neck ◽  
Operational Taxonomic Units ◽  
Phylogenetic Hypotheses ◽  
The Uk

Leptocleidus Andrews, 1922 is a poorly known plesiosaur genus from Lower Cretaceous successions of the UK, South Africa, and Australia. Historically, there has been little consensus regarding its phylogenetic position within Plesiosauria, largely because of its seemingly aberrant combination of a relatively small skull and short neck. As a result, a diverse array of potential sister groups have been posited for Leptocleidus, including long-necked Cretaceous elasmosaurids, Early Jurassic “rhomaleosaurs”, and Middle to Late Jurassic pliosaurids. A cladistic analysis including Leptocleidus, and a new, apparently morphologically similar specimen from Alberta, TMP 94.122.01, was undertaken to assess their phylogenetic position within Plesiosauria. A character-taxon matrix was assembled afresh, consisting of 33 operational taxonomic units sampled broadly among plesiosaurs. 185 cranial and postcranial characters used in plesiosaur phylogenetics were critically reanalyzed, of which 152 were employed in the parsimony analysis. The results indicate a basal dichotomous split into the traditionally recognized pliosauroid and plesiosauroid clades. Nested within Pliosauroidea, a monophyletic Leptocleididae was recovered, consisting of L. superstes Andrews, 1922 and L. capensis (Andrews, 1911a). In contrast to earlier suggestions, Leptocleidus neither clusters with Rhomaleosaurus, which was found to be paraphyletic, nor with large-skulled pliosaurid taxa, such as Simolestes. Rather, a sister group relationship between Cretaceous Polycotylidae and Leptocleididae was recovered, which is here named Leptocleidoidea. Although TMP 94.122.01 is superficially similar to Leptocleidus, several discrete characters of the skull nest this new taxon within Polycotylidae. Compared to other phylogenetic hypotheses of plesiosaurs, these results are more congruent with respect to the stratigraphic distribution of leptocleidoids. A classification for Plesiosauria is presented.

Larval morphology, biology and distribution of Agabus setulosus (Coleoptera: Dytiscidae)

1988 ◽  
Vol 19 (3) ◽  
pp. 381-391 ◽  
Author(s):  
Anders N. Nilsson
Keyword(s):  
Life Cycle ◽  
Abdominal Segment ◽  
Instar Larva ◽  
Larval Morphology ◽  
Northern Sweden ◽  
Swedish Population ◽  
The Third ◽  
Northern Fennoscandia ◽  
First Instar ◽  
First Time

AbstractA lectotype is designated for Agabus setulosus (J. Sahlberg, 1895), a rare rheophilous dytiscid known mainly from northern Fennoscandia. The larval instars are described for the first time, based on material from northern Sweden. The first-instar larva is characterized by the presence of two dorsal spines on each femur and a pair of mediodorsal setae on last abdominal segment; both characters are seemingly unique among Agabus. The third instar differs from all other Palaearctic Agabus species in the complete sclerotization of the ring-like abdominal segment 6. The biology of A. setulosus is described from a Swedish population; semivoltine life cycle with overwintering eggs laid in summer followed by adult overwintering prior to breeding is suggested.

Laxotela - a new genus of Therevidae (Diptera) from Australia

1999 ◽  
Vol 30 (3) ◽  
pp. 299-310 ◽  
Author(s):  
Michael E. Irwin ◽  
Shaun L. Winterton
Keyword(s):  
New Species ◽  
Phylogenetic Relationships ◽  
New Genus ◽  
Cladistic Analysis ◽  
Sister Group ◽  
Sister Group Relationship ◽  
Relationship Of

AbstractLaxotela gen. n. is described and figured from Australia, with five new species: L. gaimarii sp. n., L. hauseri sp. n., L. holstoni sp. n., L. metzi sp. n. and L. whitei sp. n. We conducted a cladistic analysis of all species of Laxotela gen. n. and Belonalys occulta (White). The phylogenetic relationships of Laxotela gen. n. and the sister group relationship of Laxotela gen. n. to Belonalys are discussed.

Intra- and interspecific analysis of first instar larval morphology in the genus Berberomeloe Bologna 1989 (Coleoptera: Meloidae)

Zootaxa ◽  
2009 ◽  
Vol 2089 (1) ◽  
pp. 52-64 ◽  
Author(s):  
CHIARA SETTANNI ◽  
ANDREA Di GIULIO ◽  
MARIA GRAZIA FINOIA ◽  
MARCO A. BOLOGNA
Keyword(s):  
Iberian Peninsula ◽  
Instar Larva ◽  
Species Differentiation ◽  
Larval Morphology ◽  
Morphometric Data ◽  
North African ◽  
First Instar ◽  
African Populations ◽  
Different Populations ◽  
First Time

The first instar larva of Berberomeloe insignis (Charpentier, 1818) is described and figured for the first time and compared to that of B. majalis (Linnaeus, 1758). Diagnostic larval characters of the genus and of both species are identified. Morphometric data from different populations are analyzed statistically. Results support species differentiation and characters definition. Additionally, analyses also suggest that whereas B. majalis is structured in the Iberian Peninsula, there is a lack of differentiation between Iberian and North African populations.

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