SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f8c6a35d414c1e3f5f8c4b20633b3bafab0ed140a9bd2f66dee6627d57fadcbf' 
  AND token = 'Tl5UTzwCPCHEbiIK4eHwQ/42Y5tFIeMqnNVOlTDAiPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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