SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c68b93fe024827a9cbfec64ccd7e6d0890514597574b9d5daaa138eff589370' 
  AND token = 'uPpTfaPYzVKkxATYBWXy2LPZnNXMnFLElZkw0i3YbeA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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