SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07cc4b6c07129cc2ef6f52379a95aba7e2a31604f693cb3da22aeb31ed70a7ea' 
  AND token = 'MlTQnpwxTSFvAJF6DzPoh5aVOmsODUnkBRz6bkum5oQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}