SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d945a67ee84923dda61aa86db18b3f743230e6e76d48e4b01af5705db4d682e' 
  AND token = 'be2oK0k/QdeuoGfQNR567WYTYA9/bmuVknPkJ1VcleY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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