Based on osteology, Bourque (2012a) recommended that the subspecies K. subrubrum steindachneri be elevated to full species status, as it was originally described. Preliminary molecular data provided by Iverson et al. (2013) supported this conclusion. Bourque (2015) treated this taxon as a distinct species based on morphology, and argued that no morphological or genetic data had been presented to support its continued recognition as a subspecies of K. subrubrum (Iverson 1998; Walker et al. 1998; Bourque 2012a, 2012b; Iverson et al. 2013; Spinks et al. 2014; Bourque and Schubert 2015). This was accepted by TTWG (2017).

Hurtado-Gómez et al. (2024) analyzed phylogeographic structure and taxonomic limits within the genus Kinosternon that demonstrated deep intrageneric divergences; they proposed the recognition of three subgenera: Kinosternon, Cryptochelys, and Thyrosternum. The subgenus Thyrosternum was found to include K. baurii, K. durangoense, K. flavescens, K. steindachneri, K. stejnegeri, and K. subrubrum. TTWG (in press) agrees with this proposed taxonomy.

We assess Kinosternon steindachneri as Data Deficient (DD) due to the general lack of data on population status, life history and population dynamics, and a poor understanding of its habitat use and requirements throughout its range. However, because of threats to the species' habitat in the rapidly developing central and southern portions of its range, and including barrier islands, the species could be considered as Near Threatened (NT). Previous assessments of the status of the K. subrubrum, which included K. steindachneri as a subspecies at the time, resulted in an assessment of Least Concern (LC). Combining these taxa resulted in a misconception about the status of Florida Mud Turtles throughout the peninsula. When considered as a separate species, however, our assessment of threats changes considerably. The range of K. steindachneri is limited to an area that is experiencing expanded development with an estimate of >1,200 people moving to Florida each day. The central part of the state is a major destination for these newcomers, resulting in housing and retail booms in what was formerly undeveloped sandhill and lake habitats. Although Florida Mud Turtles recently have been found on a few barrier islands, previously unreported populations there and elsewhere already may have been extirpated. The extent to which populations can be maintained through time in intensively urbanized areas is unknown.

Climate suitability models show that there will be significant loss of habitat from 2050–2070 for K. steindachneri, as compared to K. subrubrum which is showing stability and some expansion in the northeastern states. The probability of occurrence model shows severe predicted decreases in south Florida over this time period, with southeast Florida being mostly eliminated (Butler et al. 2016).

Road mortality is a growing threat as the species often traverses roads before and after aestivation and to and from distant water bodies. Increased traffic due to a growing human population results in direct mortality and fragmentation of habitats, leading to mortality of both hatchlings and adults. Highway mortality may be especially serious to females nesting in locations distant from wetlands.

Kinosternon steindachneri is restricted to peninsular Florida south of the Suwannee and St Marys rivers (Krysko et al. 2019), including a few barrier islands (Lechowicz and Mills, unpubl. data), but not the Florida Keys. The estimated historical indigenous range (area of occupancy, AOO) is 93,472 sq. km (TTWG 2021) and the estimated historical indigenous extent of occurrence (EOO) is 115,333 sq. km (TTWG in press).

Kinosternon steindachneri appears to be somewhat widespread throughout the state, however, it is not commonly found throughout most of the year. During the rainy season in south Florida or periods of heavy rainfall in north Florida, it is found locally abundant in ephemeral sites, but is considered rare in most areas due to its short window of above-ground activity (LeBuff et al. 2013).

Kinosternon steindachneri inhabits shallow (less than 1.6 m) (Bancroft et al. 1983) open or closed canopy ephemeral or semi-permanent wetlands that can include swamps, marshes, canals, ditches, flooded fields, depressional wetlands in or near uplands (Krysko et al. 2019). These water bodies can be sandy or muddy with dense or moderate vegetation. The species has been found on a barrier island tolerating salinity of 6 ppt and passing through a water body with a salinity of 20 ppt (Lechowicz and Mills, unpubl. data). The species aestivates on land during dry periods up to 255 days and has been recorded to travel as far as 212.75 m to an aestivation site (Lechowicz and Mills, unpubl. data). It has also been recorded to move 700 m from one wetland to another (Dodd 2023). Lardie (1975) also noted a hatchling ca 200 m from the nearest water body, presumably from a long-distance nesting foray. Such movements may occur rapidly.

Adult males and females are typically between 7.5–10 cm straightline carapace length (SCL) (Krysko et al. 2019), typically with maximum size (SCL) being 11.7.cm in males and 11.8 cm in females (Lechowicz and Mills, unpubl. data). Males mature at 4–5 years and females at 6–8 years (Iverson 1979). Turtles have been found gravid from October–June only (Iverson 2022). Mean clutch size has been recorded as 3.58 eggs in northern Florida (Iverson 1979, 2022) and 4.5 in southern Florida (Lechowicz and Mills, unpubl. data). Only one annual clutch has been reported, but up to two more are suspected due to enlarged preovulatory follicles (Iverson 2022, Button et al. 2022). Incubation has been reported to be between 90–100 days in north Florida (Iverson 1979) and hatchlings are between 20.0–33.6 mm SCL (Button et al. 2022; Lechowicz and Mills, unpubl. data; Dodd 2023). Additional information on size of various life stages is in Button et al. (2022). Hatching occurs in winter and early spring in central Florida (Button et al. 2022). Generation time is not known for K. steindachneri, but from previous data on generation time, if age at maturity is seven years, generation time would be 14 years, and has been estimated as 12–14 yrs in its congener K. subrubrum (Frazer et al. 1991, Iverson, 2024).

Some activity occurs throughout the year in Florida, with peaks in the winter and early fall (Bancroft et al. 1983, Button et al. 2022). Adults inhabiting temporary or permanent small wetlands estivate terrestrially in nearby sandy habitats though the hot summer months, but some turtles may be active in larger water bodies and lakes throughout the summer. Terrestrial dormancy may last for months, as it does for K. subrubrum farther north.

Habitat loss is a major threat as more of Florida wildlands undergo development. Many populations of Kinosternon steindachneri likely have been and continue to be locally extirpated as their habitats are destroyed by construction projects even before they have been identified. Fragmentation of the landscape, especially where mud turtles must travel significant distances to move from aestivation sites to wetlands and between wetlands results in significant road mortality (Meshaka and Gibbons 2006). Bancroft et al. (1983) reported a population decline over three years due to rapid development around an urban lake in central Florida. Climate change resulting in rising sea water and more intense tropical storms will result in inundation of freshwater bodies and is a threat to coastal and insular populations (Lechowicz and Mills, unpubl. data). Climate suitability models predict a significant loss of habitat in south Florida, particularly southeast Florida between 2050–2070 (Butler et al. 2016).

Legal and illegal trade in this species may be limited due to the short annual activity cycle, as the turtles estivate singly under leaf litter in terrestrial sites near wetlands. They are not easy to find during dry periods. The location of populations is not well known making organized collecting difficult. This results in low numbers in trade, which brings higher prices on the international and national markets.

Legal and illegal collection for the international pet trade is a growing concern, as the small size of turtles of the family Kinosternidae make them easy and profitable to send in large quantities overseas.

Kinosternon steindachneri was added as Kinosternon spp. to CITES Appendix II in 2023. In Florida, there is a bag limit of one per day without any type of permit, but turtles from the wild are not allowed to be sold commercially. Information on the numbers taken in legal collection are needed, as well as on turtles available from potentially non-legal sources. This could be accomplished by an examination of national and international export permits, as well as a review of Florida Mud Turtles being offered to buyers online. Prohibitions on commercial take should be strictly enforced. This species is infrequently bred in captivity at this time. Adults offered for sale online are most certainly poached wild-caught individuals.

Population estimates based on field research are unknown. There is an urgent need for life history research to better understand the environmental requirements and population dynamics of this species. Buffer zones (perhaps ca 70–275 m, similar to K. subrubrum) and corridors around and between wetlands that allow for movements among wetlands and adjacent terrestrial habitats are needed to conserve this species (Burke and Gibbons 1995, Dodd, 2023). It seems clear that turtles use landscapes considerably larger than lakes and smaller wetlands.