SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59c8e6de8f93059ac771519b0f701f82638925e1932761e464ef1f72e7674d92' 
  AND token = '+yG/J1yb6qhVeohRQ+Xcu5B4H5bthGmLqIeDZ+GLYss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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