SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f85c8e5ec637cbadfe23dd137376122e297df2d3f62f46aae2273a0d17df769c' 
  AND token = 'oFjcqPUEXC0p6hHTl5wxflKCh0ssWyRdJ2QjsRk7M0U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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