SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '43d4b9caec62c419c8a9f5940053811c6bac7a74557fab38cbdd389a848dca32' 
  AND token = 'Um2rDp56OxqvYB7+LPfmw1AwtfGWwMSGr9DgEsofCNI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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