SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2215f82c9de2d1493f5cb1ee9cf5be43a75fe329c339d86569db275909dfdee' 
  AND token = '+VofrCSx/eLugu3zUXQX5aN5UyB0wt/j8Q9davjbHRc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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