SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c0149c2d148c4563dba4853a94fc94ff734f9147c3dfbd24e1fc7f4b18abc86' 
  AND token = '4rurNbnX9LO2nv3FVZhGUoxiRfq+apwz+/J3NNYGVYw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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