SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3488df25964c85a4e50ce823b084b1d6e3d1c792cee494fecc6d07250a50f0ec' 
  AND token = 'cP7ahxfpX6zRLrlju2X+9ofBI02+TnWpT1OqHkXqpOU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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