SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'be4eaac010428a9dfb0de2d2e6f03211f90dd37d6047f630f57e305a8e33693d' 
  AND token = '8YC7jgVOGI0wcG+LIRAbrW3MKY5HgqnzwZ90cWnz01M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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