SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd710fc4ecaf64bd794790cfeb8c18113decffbf24e53b9a95e2c0845db834fc' 
  AND token = 'NfukIeAUEzMtWCM1dtaq97y5zO9hSFjGVNSg/S9EfAI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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