SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd53602e8ebb83ff393c797e8a933dfe9523a7e9af056dfa4a11f5e94252a99c' 
  AND token = '1dRLlc4H0rclYAnj26nnXkPNYHycgSxeDYdLIsvEsR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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