SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03ff3cc6a2571f33ec853d4b315394a2f3b85f0ecf83f584567fa799f8fbdfbb' 
  AND token = 'ltsKrB/AJuZdlhMtKU0s+I+K/1qUNs5UTkA4cFVooxw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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