SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f72195ec1584a567c7a933d1f3971cdef671e74137b9c68cfa803492f0a6f31d' 
  AND token = 'qboGVotUME58pt4yXrg/95tNC5LMvGYwtGKBHPOKQmk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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