SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ac6fbe3efd3495055c22dd4b09fa9eadf6682ec9e2cff732b05e3768086ab177' 
  AND token = 'Sk7sl4sP+BgsLFFL55JdTVWhfGxESmmCqq2iyTlpqRA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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