SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a04458cc3992a6ebbd63e1150ec1c99ece666b2751b0a9fafa690149c54d608' 
  AND token = 'V6YhngNLxgTWk1WAPL+hMXmILWxQd8mCS9Mb3O9pH6Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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