Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55cf4aa88f4ac2790166a9fbd8c9a749335af61c60e2540cc90e62c16294a268' 
  AND token = 'SChiiLk3XrEamibx19uy6SgdVv7z1eYBd6cif27C6jM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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