Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a6d3e48ecdab43f2d2d6bea4d5fdf5f8e03ba4e8fb2c00403099010eb05b2752' 
  AND token = 'hKsTWWEdPZ7dKYs4HexSYAr/7PP2O/UY768a3rwDkjk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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