SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f7a89439f2308f8736cebc990fa7ce4bd514c8a6123ac7ad5d55c9d4a563cf0' 
  AND token = 'qm2CmALGOAROLYFy4nQuDPoiCNUIk9b+wjgt8kzXzVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

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