SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '89a7db33079e806f56aa3fea728fe845e80f624be5b67d0d6a2c84daa86419e4' 
  AND token = 'VTB65XjMgWHvkdsRtGFBj5SMzid5JPd9UfJPIK9L5PY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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