SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3577790c1e680a9d621f0cdc777dee942bc28a543579ed0e80db581da8638935' 
  AND token = '31lc1YS392fM+b+km07HSNaPiopmmaUdhg4I1+VEI9I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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