SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bae3bcc99694b60afaeded2d2c87668ad2a91d23ea14f7fd812963ba97af8fa2' 
  AND token = 'Gfoud9GhnFvb4yIpoM8VvjjRgr+B8x5+4IVPp0PeuPc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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