SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a289c610fa6664522396f5b7dc7511a157383c524b830483edcd864d3291596' 
  AND token = 'GGD01kOnuYTILuOfdlhOszSoDvX4Uk8O9wqWPzgI9B4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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