SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '261599b92af446074b442422f1751bc5f12d9347965b3e261335ba6fa4490de3' 
  AND token = 'AMJipdH6IZXLJSuBitMfqfKtpucWCbRE9sntkppzjvE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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