SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c803a4791b24378ec70eb0c9049581f4fce0f7b135217a27a308db09bf193116' 
  AND token = 'aek2mzOXn6VLgPcHGXMfR8tW4Ev1OVcSS3Mc793K2A0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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