SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'cfd0c82798016768a4fd5eb54eef78f63a6ff432062fab4c73924cedcc43f3dc' 
  AND token = 'YPaNUuBIkKJPOfVI4EI7ZKGu/SEegzHbrXIx2qondiE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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