SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1160422acc6cb40896312b6e789b88fb66c904fb682dd89435c62312ebd8621e' 
  AND token = '60UaMHeiyyMV/JAkjZYwJXP0SSVq+CRtLzGjZSQ+ndI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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