SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd3340dd9e9b98eeee9788a965ba90b632b4abfbba46f70ac9fc938224679ef7d' 
  AND token = '40DKBASLnkvCSWcfYIYSkrfWmvuoaaHHWAXRYWuhV7U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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