SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '668b9494574de7da47459994ad03664dedf76e2f1da88020b4d8e0e429f6511b' 
  AND token = 'RILps7pdFROGhLiTvl4o58CeCDuIbjNok6JX3Sm8h2Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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