SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1919bfd4f52dab1bc31b80b88ab77bdd7b69e1c9dc15b30a015d6ad80846c726' 
  AND token = 'YWL50QvD7SrzJZ2O5Vnv4IWDmSJVVshsmp+mJ4y0Et4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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