Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f4e8e9711e9b015068eed72a059d1925d8ea7b1dac9988a2996021dc2b4405c' 
  AND token = 'I7rT26Ki3e7nCpLfEsvvkMiBbOF8p0Pp8lFwn9+fk1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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