SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c47ebd0ba411ad17943413b090da8ab31df552f3692e3e3cf21f61ae2b1c1a0a' 
  AND token = 'N86XudJRgf2PalLS9voNGN8sO8CGQv/q/cKTGYhv7rM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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