SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13adf09ffcfa1af4e8b7335804e73794bee505a7288e36986a2ef13d21a98651' 
  AND token = 'gKjjkFh94xjCLgIdg7EkXgfvKyIX/X5H46OdWpt38P4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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