SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e06da873aef136fe78731cf50f1ca0a4470436b7d04dc438e6bc62b678bd297' 
  AND token = '3cSha6SGVg94cBk8VtjwYeZoYFwHELcZaGwzgD4Ww/8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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