SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccaf8fc4398579df47017e86279a327a9ce675c3be36665432c4d4c0041f024d' 
  AND token = 'EKzyF5C/4hiKqTZacPr/S6LDtvV4wEtYaK4joiuLgW0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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