SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cffddd379842831cc16ab243437dbe4cd3963403cef31d65aea1c2b520733e6f' 
  AND token = '/OkgIrKDobrwIuCkOByDgSfL8ife2OLdjq/F9Xnax74=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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