Chironius flavolineatus

Chironius flavolineatus
Conservation status
	; Least Concern (IUCN 3.1)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Colubridae
Genus:	Chironius
Species:	C. flavolineatus
Binomial name
	Chironius flavolineatus; (Jan, 1863)
	Predominant distribution of Boettger's sipo

Last updated November 01, 2024

Chironius flavolineatus, also known as Boettger's sipo, is a vine snake species in the family Colubridae, endemic to savannas and semiarboreal biomes in Brazil, and much of South America.^[1]^[2]^[3] It is listed as least concern on the IUCN Red List since 2014.^[4] It is a member of the Genus Chironius which is composed of twenty-two other described snake species.^[5] It is nonvenomous, using camouflage or burrowing as a form of defense.

Description

The Chironius flavolineatus's distinguishing trait is a yellow or cream white vertebral stripe that extends for nearly the entire length of the snake's body. On either side of the stripe, black sides that begin after the first row of scales lie anteriorly. The back of the Chironius flavolineatus's head ranges in color from tan to brown and is distinct from the superior third of the body, which is black or dark gray. The Chironius flavolineatus usually has a single posterior temporalis muscle, a divided cloacal shield, and white, unpigmented ventral and subcaudal scales. Chironinus flavolineatus also features 0-4 rows of keeled dorsal scales in its midbody and a static color pattern throughout its lifetime^[6]

Studies indicate that Chironius flavolineatus is sexually dimorphic. Adult females tend to be larger than males, with an average weight around 81 g (2.9 oz) and an approximate total length of about 1.16 m (3 ft 10 in). Adult males weigh approximately 60 g (2.1 oz) and reach a total length of around 1.10 m (3 ft 7 in). Males tend to have long tails and larger eyes than their female counterparts, while no dimorphism is seen in the head size of the sexes. The smaller size of males indicates that there is limited male to male combat for mating. The differences in eye diameter, which has been observed in other members of the Chironius genus that live in the Atlantic Forests, is often linked to male-exclusive activities such as searching for females. Females members of the Chironius flavolineatus only begin to reproduce when their body is large enough to carry their eggs. This likely creates the selective pressure that leads to females being larger than males throughout the species. The thin body and long tails of the Chironius flavolineatus indicate that they have arboreal tendencies when in savanna environments. This speculation has been reinforced in natural studies, which show Chironius flavolineatus members foraging on the ground before resting at night in above-ground vegetation.

Distribution & habitat

The Cerrado (Tropical Savanna) Cerrado.jpg — The Cerrado (Tropical Savanna)

Chironius flavolineatus has no specific locality and has been reported in São Paulo, Amazonas, Rio Grande do Sul, Pernambuco, Rio Grande do Norte and many other regions in South America. It is found predominantly in Brazil, but is also found in Paraguay, Bolivia and Peru. Chironius flavolineatus is commonly found in areas that are between 100 and 400 meters above sea level in biomes such as semiarboreal forests and grass steppes.

Behavior and ecology

Chironius flavolineatus has various defense mechanisms that prevent itself from being killed or harmed by predators and utilizes camouflage. The main defensive behaviours that these snakes use are cryptic coloration, camouflage, and mimicry. For example, this species will submerge themselves in a pile of decaying foliage matter where it is not able to be detected until the threat or predator can no longer be observed. Another unique escape tactic the snake uses rarely is diving; there are several semi-aquatic snakes that regularly use the water as a defense however C. flavolineatus, an arboreal species normally would not. But when foraging near a river, it dived in as an attempt to escape.

Diet

The diet of C. flavolineatus like other snakes in the Chironius genus consists fairly exclusively on frogs. The specific frog family preferred by these snakes is Hylidae which consists of a wide range of tree frogs. C. flavolineatus also have a taste for various small prey that they may find around their environment. These snakes are very active foragers as they roam the ground or arboreal substrates to acquire most of their diet. Likewise, their diet is also composed of nocturnal prey considering they are diurnal active foragers. Some examples of their prey include: hypsiboas albopunctatus, hypsiboas bishofi, scinax cf. fuscovarius, etc. When eating, these snakes will more often consume their prey by swallowing headfirst. After a meal, C. flavolineatus will use their surroundings vegetation to rest in while their slow metabolism digests their meal.

Reproduction

The Chironius flavolineatus males reach sexual maturity when they have enlarged testes and opaque deferens ductus (this is where its sperm is stored) and females reach maturity when they either have ovarian follicles and or oviduct eggs. Female snakes exhibit a seasonal reproductive cycle, during the months of a rainy season which is when vitellogenic follicles and oviduct eggs are most abundant for fertilization. C. flavolineatus eggs lay around 21 eggs and have an average diameter of 34.4 ± 6.4mm; with a range of 25.1–51.3 mm (0.99–2.02 in). Male snakes, however, have continuous sperm production (in the testes) and storage (in the deferens ductus). The females of C. flavolineatus are typically larger than males because of the strong preference males have for a large snout-vent length in females.^[7]

Courtship behavior was recorded in October during the rainy season, and data shows that mating in Chironius occurs at least in two periods of the year. As oviparous species, these snakes will develop eggs inside their bodies and will be laid in an entire clutch (N=21) at once. These eggs will need to be incubated at the proper temperature around 19 to 32 °C (66 to 90 °F) and humidity level for embryonic development before hatching. Once hatched, the snakes are called hatchlings or neonate snakes and will continue to grow to maturity.

Related Research Articles

<span class="mw-page-title-main">Colubridae</span> Family of snakes

Colubridae is a family of snakes. With 249 genera, it is the largest snake family. The earliest fossil species of the family date back to the Late Eocene epoch, with earlier origins suspected. Colubrid snakes are found on every continent except Antarctica.

Loxocemus bicolor, the sole member of the monotypic family Loxocemidae and commonly known as the Mexican python, Mexican burrowing python and Mexican burrowing snake, is a species of python-like snake found in Mexico and Central America. No subspecies are currently recognized. Analyses of DNA show that Loxocemus is most closely related to the true pythons and the sunbeam snakes.

Imantodes cenchoa, also known commonly as the blunthead tree snake, the neotropical blunt-headed tree snake, and the fiddle-string snake, is a species of mildly venomous, rear-fanged snake in the family Colubridae. The species is native to Mexico, Central America, and South America.

Oligodon is genus of colubrid snakes that was first described by Austrian zoologist Leopold Fitzinger in 1826. This genus is widespread throughout central and tropical Asia. The snakes of this genus are commonly known as kukri snakes.

Elaphe is a genus of snakes in the family Colubridae. Elaphe is one of the main genera of the rat snakes, which are found in many regions of the northern hemisphere. Elaphe species are medium to large constrictors by nature.

Chironius is a genus of New World colubrid snakes, commonly called sipos, savanes, or sometimes vine snakes. There are 23 described species in this genus.

The eastern trinket snake is a species of snake in the family Colubridae. The species is endemic to South Asia.

Opheodrys aestivus, commonly known as the rough green snake, is a nonvenomous North American colubrid. It is sometimes called grass snake or green grass snake, but these names are more commonly applied to the smooth green snake. The European colubrid called grass snake is not closely related. The rough green snake is docile, often allowing close approach by humans, and seldom bites. Even when bites occur, they have no venom and are harmless.

The emerald-eyed tree frog is a species of frog in the family Hylidae. It is largely restricted to the Atlantic Forest region of Brazil. Some populations previously regarded as Boana crepitans have been separated into the species Boana xerophylla and Boana platanera.

Itapotihyla is a genus of frogs in the family Hylidae. It is monotypic, being represented by the single species Itapotihyla langsdorffii, commonly known as the ocellated treefrog. It is found in the Atlantic Forest biome of Brazil, with an isolated population in eastern Paraguay and adjacent Brazil and northeastern Argentina.

Langaha madagascariensis is a medium-sized non-venomous highly cryptic arboreal species. It is endemic to Madagascar and found in deciduous dry forests and rain forests, often in vegetation 1.5 to 2 meters above the ground.

Dipsas is a genus of nonvenomous New World snakes in the subfamily Dipsadinae of the family Colubridae. The genus Sibynomorphus has been moved here. Species of the genus Dipsas are known as snail-eaters.

Chironius laurenti is a species of nonvenomous snake in the family Colubridae. The species is endemic to Bolivia and Brazil. The species was named in honor of Raymond Laurent.

Mastigodryas is a genus of colubrid snakes. Like some other colubrids, they are commonly called racers. It is a Neotropical genus, with members distributed from Mexico to Argentina and several islands in the Caribbean. Some authorities use the older generic name, Dryadophis, for these species.

Philodryas olfersii is a species of venomous snake in the family Colubridae. The species is endemic to South America.

Oxyrhopus guibei is a species of snake in the family Colubridae. The species is endemic to South America. It is often called the false coral snake, but this common name can refer to any of a long list of other species, genera, and even entire families of snakes. Many nonvenomous snakes have evolved coloration that mimics that of venomous true coral snakes, a trait which helps them avoid predation.

Synophis bicolor, known commonly as the bicolored shadow snake or the two-colored fishing snake, is a species of snake in the family Colubridae. The species is endemic to northwestern South America.

Synophis insulomontanus, known commonly as the mountain shadow snake, is a species of snake in the family Colubridae. The species is endemic to northwestern South America.

Boiga dightoni whitakeri, or Whitaker's cat snake, is a subspecies of nocturnal, arboreal, opisthoglyphous snake of the family Colubridae. It is endemic to the Western Ghats of South India, in Kerala and Tamil Nadu states.

Atractus francoi, also known commonly as cobra-da-terra in Brazilian Portuguese, is a species of snake in the family Colubridae. The species is endemic to Brazil.

References

↑ "Chironius flavolineatus Jan, 1863". www.gbif.org. GBIF . Retrieved 2020-11-04.
↑ "Taxonomy browser (Chironius flavolineatus)". www.ncbi.nlm.nih.gov. National Center for Biotechnology Information . Retrieved 2020-11-04.
↑ Hamdan, Breno; Pereira, Anieli G.; Loss-Oliveira, Letícia; Rödder, Dennis; Schrago, Carlos G. (2017-11-01). "Evolutionary analysis of Chironius snakes unveils cryptic diversity and provides clues to diversification in the Neotropics". Molecular Phylogenetics and Evolution. 116: 108–119. doi: 10.1016/j.ympev.2017.08.004 . PMID 28804036.
↑ Cacciali, P.; Scott, N.; Gonzales, L.; Nogueira, C.; Hoogmoed, M. (2019). "Chironius flavolineatus". IUCN Red List of Threatened Species . 2019: e.T15158734A15158743. doi: 10.2305/IUCN.UK.2019-3.RLTS.T15158734A15158743.en . Retrieved 2 November 2020.
↑ Hamdan, Breno; Fernandes, Daniel S. (2015-09-02). "Taxonomic revision of Chironius flavolineatus (Jan, 1863) with description of a new species (Serpentes: Colubridae)". Zootaxa. 4012 (1): 97–119. doi:10.11646/zootaxa.4012.1.5. ISSN 1175-5334. PMID 26623847.
↑ Augusto Vuolo Marques, Otavio; Fernandes, Ronaldo; Richard Pinto, Roberta (2008). "Morphology and diet of two sympatric colubrid snakes, Chironius flavolineatus and Chironius quadricarinatus (Serpentes: Colubridae)". Amphibia-Reptilia. 29 (2): 149–160. doi:10.1163/156853808784125027. ISSN 0173-5373.
↑ Marques, Otavio A. V.; Almeida-Santos, Selma M.; Rodrigues, Murilo; Camargo, Ricardo (2009). "Mating and Reproductive Cycle in the Neotropical Colubrid Snake Chironius bicarinatus". South American Journal of Herpetology. 4 (1): 76–80. doi:10.2994/057.004.0110. ISSN 1808-9798. S2CID 55247228.
Hamdan, Breno; Scali, Stefano; Fernandes, Daniel Silva (2014-05-05). "On the identity of Chironius flavolineatus (Serpentes: Colubridae)". Zootaxa. 3794 (1): 134–142. doi:10.11646/zootaxa.3794.1.6. ISSN 1175-5334. PMID 24870316.