SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7be08d54f7320fd209c6f195a12c99aae2be3f04bd7ebe4f5336aa5366f8ab16' 
  AND token = 't1h1NexrVrbNwaUJl3eQWlVL8VtSO8nkfiBm8tFBUTM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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