SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0429e3518b8cda5cd6b1f45e53ee6aece0c7002a79ef92d9495773f40700b16c' 
  AND token = 'mVwQ2wbCW3RIS5FOkl8VZpiBJ7TznT07xIS2+42e3n0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}