SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fea6be813798e278aa52c8ce339098f7a82bc3a7124633110a545f7842b8dda6' 
  AND token = 'Q+RMmCqZdLzgCYY6zBr3is/TLTSkqaWKd2EdUoP8cUc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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