SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60e1a10aecebb90742d0a1f012e250f30fe65047a5d89024e82ab59eb2410a08' 
  AND token = 'Hr9n96Glew9YGadjlBDbPe1yYQGpwVoNAd8t/RK7CkQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}