SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '89642512ed1f4658263a8bcb363ff4ac3c8b40532eae5dfecbbce6a252c36596' 
  AND token = '7N0pMgscL81UFADIxWKO8TIdsmAubx6+iJFCidSxF3U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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