SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ca5ea2df311c1ab35c399107c14f8ae4ce065ff9d11efbd754cdefea6343718' 
  AND token = '+NxWBrHnR2IhmDNJOl7ACUVKB2j11WAC+HyNKXJ6A/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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