SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2afae11bf6436861f762ffb67c845c94f0044cb8ad6d22a80e9767b1b3db1e54' 
  AND token = 'VZ1sZlZQ+90LUoNN+PWI4KQyuHzIOwjHViUs/hat43U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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