SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '195efca6e8e1da394eb43487a2e0e8d53075d8bf16087927174c5aad637efb30' 
  AND token = 'XM0D6tlYupholi3Bo+jXIoCSzEwPA94QiM00hxw81j8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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