SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '21268ef4836c9e3cb7e5ba087d86825f4e4143bd9fd09dc8f2bcb37a2a9f4b4f' 
  AND token = 'vG9orOjF2NdOtKO0/zk69WwWKExuj55i4N47VhHfgic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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