SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '218f53225dd32e2b96332827922ae2883abf76dfc16e04cc51c75a2f2c5b27e8' 
  AND token = 'pVpjDCsckF8mgkRQJSiEXDTO99lGhe2NDVwK1uO0lIM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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