Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a51bc29a864ee94489aba3f5757109d95bf2f93bfdf0d1cc017fd29323f70c9d' 
  AND token = 'w1533i2dUnL74oaOtI61JrNhlpE+WLfdvMOjZyCrFUo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}