SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb6695d819bdfdfa93597741e0ec751b18446fcbf232db3955ab7f28a724da62' 
  AND token = 'OBk2XrNh9xOGu4a0EE3WaPEuqPX4l4F5YCvzCAWX4lE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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