SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e05c5765342a706d257d0c17f5bd4161d8d0d3b17a2f0eeca6d1b416d1f8e9a9' 
  AND token = 'NdwX5fdNgGlNymR7vRMMw3DxKq3Vs+X7DQl1VDebxoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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