SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96430cd152eae826db2233ec964bfc443e6496f96a65fa284fca6d39b44dc92e' 
  AND token = 'dETiH7QqNOKfhdLfXLJzibWQ89sntloDdTWopkU4UtY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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