SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '362fc098ababb3d5b12b97c3258b31d4e7800408ec5208c95c8bc2b429016d7c' 
  AND token = 'W1iMX4lzheTgW8VbbRNRZE1ifWbrcOZnrJP60PfNIAI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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