SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a9de2c4ed2abc9aedde9e4c0e4978320b347adef7ab381cf6a8037fe31b8083' 
  AND token = 'FM8WirosYqRtq8oRub8NxVRTAV4HkTQyqGqJffFwgP0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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