SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f381340c609b98051fb34c9b1d1e3e3c2a9199401b92f378d68b4a49522139d' 
  AND token = 'ZDJ8KaIZelAKRPLiXMfGgq9ypLh37ugl+BDBA+v/af0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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