SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd3dc6213bc838649a24ba47899bc24838e87dca17fbd66c13071d73004d547df' 
  AND token = 'IL+peG6HsJNyz0+H3CcwBpFKIBLZhS2bgXZ/3tZpKg4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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