SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c9a924e9ca7d28f5713d00ccbfb34b55219b41545e43a6ed4751640a59823bb' 
  AND token = '0BzVajC9U8AvXjIBAvHyi5/E8ZBxLHPRRDzqpFI3hL8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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