SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '479f8a55777f1a25227938bce490d7803e85bad2b0b6a438d968d44efd16a546' 
  AND token = 'EsWxuzp2DEUZzZ4k/27RcY8/PW6b6BLyjsjUsDBW2KY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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