SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7de3608ef8829fb156ffbf4746254c5ac4b1ce96f04ba6431f3ab0e7744df6d' 
  AND token = 'CFHvrkBgjh/uzJIa9KeCMjTs+8BwpVK0BvOpbsKgflY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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