SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03fdada0891b1c2dd7295436199556c5e917fded6e6d1a0ea006290628983e8a' 
  AND token = 'DRi0wlpNL7fltXUf69sTc4+l4dXEhOHNP54a0gQt/Ts=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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