Origin And Natural Habitat
Southern California and the Baja California peninsula of Mexico form the range of Aphonopelma steindachneri, with the population most centralised around the metropolitan areas of Los Angeles and San Diego and extending south through Baja California. This is one of the few tarantula species anywhere in the world with a confirmed wild range that overlaps substantially with a major urban centre, and the chaparral hillsides, suburban canyons, and coastal sage scrub of greater Los Angeles are genuine wild habitat for this species rather than marginal fringe territory. The Mediterranean climate character of this region — hot dry summers, mild wet winters, persistent coastal influence — shapes the seasonal biology of A. steindachneri in ways that distinguish it from the monsoon-driven desert species further east.
The breeding season runs from July through October, when mature males leave their burrows and wander across the scrubland terrain in search of females — a timing driven by the dry California summer rather than the monsoon rains that trigger wandering in Arizona and Texas Aphonopelma. Between breeding seasons the species lives entirely underground in silk-lined burrows excavated in well-drained soil across arid and semi-arid terrain, emerging at night to hunt invertebrates near the burrow entrance. The widespread distribution across a heavily urbanised landscape means A. steindachneri has proven itself tolerant of habitat modification — a quality that has helped it persist across a landscape that has changed dramatically over the past century.
Scientific Classification
First described by Anton Ausserer in 1875 as Eurypelma steindachneri, the species accumulated two junior synonyms — Aphonopelma phanum and Aphonopelma reversum, both described by Chamberlin in 1940 — before the 2016 ZooKeys revision by Hamilton, Hendrixson, and Bond confirmed through morphological and molecular analysis that all three names referred to the same species. The species name honours Austrian zoologist Franz Steindachner, a prominent nineteenth-century naturalist. The World Spider Catalog and iNaturalist confirm A. steindachneri (Ausserer, 1875) as the current valid name. Full classification: Kingdom Animalia, Phylum Arthropoda, Class Arachnida, Order Araneae, Infraorder Mygalomorphae, Family Theraphosidae, Subfamily Theraphosinae, Genus Aphonopelma, Species A. steindachneri (Ausserer, 1875).
Species Overview
Among the California Aphonopelma species, Steindachner’s Ebony stands apart for one reason that no amount of ecological or taxonomic context can diminish — the adult colouration is extraordinary. The deep black or dark brown appearance draws consistent comparisons to the Brazilian Black (Grammostola pulchra) in keeper discussions, and that comparison lands accurately because the quality of the black is genuinely similar — uniform, velvet-textured, and light-absorbing rather than simply dark brown in certain lighting conditions. The difference is that G. pulchra commands prices that reflect its South American origin and rarity, while A. steindachneri comes from southern California, is increasingly available in captive-bred form, and carries the full beginner-appropriate Aphonopelma care profile. The extremely slow growth rate is the honest counterpoint — this is a spider that asks for patience measured in years before the full adult colouration develops, but for keepers who find long-term projects rewarding it is one of the most satisfying journeys available in the North American hobby.
Appearance And Size
The colouration is uniformly velvet black to deep dark brown across the entire body — carapace, abdomen, and legs all share the same deep, almost matte-quality darkness that makes the spider immediately distinctive against any substrate. Dense setae covering the body give the spider a slightly furry, textured quality that adds to the visual richness rather than distracting from it, and freshly moulted individuals show the most saturated and vivid black before the setae settle into their everyday tone. Juvenile colouration is more muted and brownish, developing progressively toward the adult black through successive moults over many years.
Adult legspan reaches 5 to 6 inches depending on the source — The Molting Pot lists 6 inches while Franksbuggin661 lists 4 to 5 inches, and a practical working estimate of 5 to 5.5 inches covers most captive adult females. Female lifespan reaches 25 or more years. Males live 5 to 8 years after sexual maturity.
Housing
A terrestrial enclosure with floor space as the priority and adequate substrate depth for a fossorial burrowing species. A footprint of 20 by 20 to 25 by 25 centimetres suits adult females at 5 inches legspan, with 4 to 5 inches of substrate below and height kept to twice the legspan maximum to protect a heavy adult from fall injury. Juvenile slings are highly reclusive and prefer to burrow, while adults become progressively more visible and may spend time near the burrow entrance — a developmental shift that makes the years of patient juvenile keeping ultimately rewarding. A latching lid and a pre-formed starter burrow at one end give the spider immediate structure and security on arrival. Our best tarantula enclosure guide covers terrestrial formats appropriate for large California native burrowing Aphonopelma, and our best tarantula sling enclosure guide covers the smaller formats needed through many years of juvenile development.
Enclosure’s Decorations
Cork bark flat or positioned to create a sheltered cavity at substrate level, with a pre-formed burrow beneath, gives the spider its primary retreat option and a starting anchor for the silk trip lines it will lay around the entrance. A shallow water dish on the opposite end provides consistent hydration. Some keepers add flat rocks or dried chaparral plant material to reflect the southern California scrubland habitat this species calls home. Our best tarantula hide and best tarantula cork bark guides cover appropriate shapes for California fossorial terrestrial species.
Substrate
Four to five inches of dry to lightly moist substrate that holds burrow structure. Coconut coir and sand in roughly equal proportions gives the drainage and structural firmness appropriate for the well-drained soils of the southern California coastal scrub range. Slings benefit from slightly more humidity than adults and are more susceptible to desiccation, so a lightly damp lower substrate section is appropriate for young specimens while adults can be kept considerably drier. The Mediterranean winter rainfall of the range suggests a seasonal moisture pattern rather than year-round aridity, and a moderate moisture gradient reflects that character more accurately than bone-dry conditions at all times. Our best tarantula substrate guide covers dry to lightly moist blends appropriate for coastal southern California Aphonopelma.
Water And Humidity
A shallow water dish at all times, refreshed every two to three days. Ambient humidity of 45 to 60 percent is appropriate for the Mediterranean coastal character of the range. Enclosures must be well-ventilated to prevent mould growth, particularly for slings maintained at slightly higher humidity. A hygrometer confirms actual ambient conditions, and a fine-mist misting bottle provides targeted moisture additions when needed.
Heating And Temperature
The southern California coastal climate maintains moderate temperatures year-round — warmer in summer, cooler in winter, with the marine influence softening the extremes relative to inland desert areas. A captive range of 65 to 80°F suits this species well, and most temperate indoor environments provide appropriate conditions without supplemental heat for most of the year. A side-mounted heat mat controlled by a thermostat handles periods when ambient temperatures drop consistently below 62°F. A thermometer at substrate level confirms actual enclosure conditions rather than ambient room readings.
Diet And Nutrition
Crickets, dubia roaches, and other appropriately sized invertebrates every fourteen to twenty-one days for adults, consistent with the very slow metabolic pace of this species. A noticeably distended abdomen is a cue to reduce feeding frequency rather than maintain a rigid schedule, because a spider adapted to food scarcity in the Mediterranean scrubland will eat enthusiastically whenever food is available. Juveniles can be fed every seven to ten days to support growth through the long development period. Remove uneaten prey within 24 hours, and leave the spider completely undisturbed when it seals its burrow before a moult. Our best tarantula food guide covers feeder options and sizing for slow-metabolising California coastal Aphonopelma.
Compatibility
Solitary only. The July to October breeding season documented in wild males provides the appropriate timing for introduction attempts in captivity. A well-fed female and supervised introduction are essential, with prompt male removal after mating is confirmed.
Behavior And Temperament
Docile and reclusive in combination — with the reclusive quality dominant in younger specimens and the docility becoming more practically visible as adults settle into surface-retreating behaviour. The all-black velvet appearance combined with docile temperament makes this species genuinely compelling as a display animal for keepers patient enough to reach the adult stage. Urticating hairs are present as the standard New World defensive tool. Biting behaviour is rare and venom is medically insignificant to healthy humans. Our are tarantulas nocturnal article covers the activity patterns of California coastal Aphonopelma and the summer wandering season when males are most conspicuously active above ground.
Handling
Appropriate for calm individuals with the standard floor-level protocol and slow movements. The deep black adult colouration makes these spiders particularly striking in the hand and the temptation to show them off is understandable — venom is medically insignificant to healthy humans, and the docile genus character makes handling a manageable activity for experienced keepers who choose it. The extremely slow growth rate means any handling sessions with adult specimens are years in the making from a sling start.
Health And Lifespan
Females live 25 or more years in captivity. Males live 5 to 8 years. The species is hardy within appropriate Mediterranean coastal conditions. Slings are more susceptible to desiccation than adults and need closer humidity monitoring during the earliest stages of development. The primary health risks across all life stages are the standard Aphonopelma combination of chronic dryness without water dish access and excess moisture causing moulting complications. Our tarantula dehydration article covers identification and recovery for dehydration-related concerns during the long juvenile development period.
Price
Available in captive-bred form from specialist US vendors with increasing regularity as the species establishes itself in the hobby. Bug Cage Company and Spider Shoppe both stock this species periodically. Slings typically sell for $40 to $80 USD reflecting the rarity relative to more commonly bred Aphonopelma. Juveniles range from $70 to $130. Confirmed adult females, being rarely available given the extraordinary growth timeline, command $150 to $250 or more. Source captive-bred specimens only — California wildlife collection regulations apply, and the responsible approach is always captive-sourced animals. Everything needed to keep this species correctly across its extraordinary lifespan is on our best tarantula products page.