SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ff27656a06fcf16e121d0c6e24fe5fdf831c7ad403c81ce771a440171f9e5ad' 
  AND token = 'F8Tg2i/xQMHi91nz15H6WbOMrMiTZeGDyHPafd70YKI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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