SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '131a218bd9540c3922b925f419c561e50ccdc49f5ca223473b24033c495949a7' 
  AND token = 'QzOM8BI1cBi+/oljQADqwXja7HCLaiLetOxaEMQFNw0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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