SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd398961f5d220e150209cbf863913a9d94422ff43da3fe477fa68b963863f1de' 
  AND token = 'UmxNpyu/yvGcN2nu/0BqPdC7FL5EdX0FS5EjkVZERcM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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