SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8fbb986658434ed7503c96890ee2f22b4a36d78827abc933374bd832fd6000cf' 
  AND token = 'GEaWl+Yvfvf2kdk6VYAWPBEcg+dUx/cL87KMOyp6WUs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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