SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74832042e5ebdc1802c26d9e238825cb01f71517a05f59f974b62d51e3d9f7c4' 
  AND token = 'KAF7ON8Vm7ex9KSj+09m/InEC+Bkzwzu1ggDZ/ivLPA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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