SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1e75ac090031944722c773b69ed5fbf2077c110392a85c5992e31b83ec45077' 
  AND token = 'Ck0YafpaIBdlSbvjKMGWDwFn4A6bJc0twnvuyW4d9pI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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