SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac32ab886a24d85b9fae014793c033fe2ed8e922afeb01a36109024f44d33a3a' 
  AND token = 'n9ZZ5M3jD7w0E0biSoaX2lCOZq4YgksjmU2s0zYPJGM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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