SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efa92d9eefe33df6c8a44200ad64916172e522dd8a43af51079c400cdc7debb6' 
  AND token = 'limBFJEeDGiipmRXjUhBWKU1TbBxvUSpdzM/yDBZxDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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