SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69b0310607221b45516855b6f40e6b8824922c505cf6581120a0f20784c909eb' 
  AND token = 'l2C23Kvu+6m3DWGtqsRLTvdcgoZmCD5qS44jO6tlYNk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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