SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a5538380c3f60e036475cce873d3309375e50ac702260ba1eab6fa47d58cd86' 
  AND token = 'QlVX+EywzecmMeivXsFoQwDZYYWFx63/X4CenmxRUjE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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