SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3b5463fdf5ca0a554a85c41a501dbdab2c888552455733c3db261a2f1f965add' 
  AND token = 'MjZUm0eSRHslCNujyktHQJNDuTKvHIjdKjt0PrIeqZ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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