SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1ffc413e3a3214e9f8ad52076bd265d396026a6b02a3ded3eb90c55f4eea1d47' 
  AND token = '7wDcbjv3Noy8LUl8yDCTmhZmOcbByKvos4rmiTOyJRI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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