SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7960d4cd8eee59dcdc1dbe46f1001cca28a4cf95ad18109d1929b33ab37b9128' 
  AND token = 'OwvWq4GUl4PJiOg58aTiFLyejKBXZmhjP+hoUJ9JmqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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