SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eaabc9bc79c06c15ed93dcdb6f968cb77918642190de80422c63399beddbd5a3' 
  AND token = 'ahQIg1tLO+7wTJisJLNRYkY65eGaer2UTOZmqUiCqz4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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