Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '345687fc102244a886e906275ce4a86c9041def4cc85a22da01eb50d4f1fcb7c' 
  AND token = 'segxoaQiO+/Pj0d9+ZrzAwIOmyMZ0FrDE/by9rzGzGM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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