SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f47ce382e3cb22bd77ec0a04212fb041e9c80c0022c507fc65ffc405cf24a047' 
  AND token = 'f+V/1uDjE+XtsFhOgw14Yp4yQUWsWFv23LCFkXLOjSE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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