SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11e061d0a70c190bfd1f29dd3e137520c05595fbafa8a78ac659afc818a20e5e' 
  AND token = 'YiXgD4BB1yezLD8PGJAgnSz2GW9GoWsDtfsEcVxerJM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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