SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '897d207ada9c513bee5ac39152b9fd44ffc89d5210771b20d44afb6947dca8fa' 
  AND token = 'ZjEhwt8XrCfDbySdywqKtLeyrvELhIS1ffONimMDUo8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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