SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '26a7560e529c60933f5799f67c1c8d66f95d7e80c4075410bf8ce87102aafced' 
  AND token = 's/r+ruJPfmiHo/LhHnT4N2bBXinxflLGBTznxlXzVcM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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