SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0b609144eeb48190476baa3f7bcfc4d53a137d37b2505e155757843b5d9a67d4' 
  AND token = '+6ch3FA0KRpWccSMkgb9FOgBQ+G7WmRtuJILQBOZTaQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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