Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccf65e64557e5e68ebf1fda6b944c2fa1b9c8e2100ec1570c93e6981f536c44a' 
  AND token = 'mkqz3jL6iUHNCjBOcCKXaIFQcSppKCVHNDbUE1TRHSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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