SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8157de2b0bf5cf1d5f436cdc9aee83e76844c653d5003788c4679693a8958f35' 
  AND token = 'ZdHPJEg1cOtV1Ev+Cy6EkqIWr9qhQWB/MvIuSYW+uX8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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