SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '092a0c54d5781c6e359c42e4ae8966d95c8d33ae8b24166ada9f28d667697968' 
  AND token = '8DysQAkttEm7LOLviSnFq3Syao+TIFxoxu60c67LkwM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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