SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b2c0185ddd82e253c5f68ef390ccb63afaa037bb9f8cf6556f8153fd6c88ca50' 
  AND token = 'v4CHKmGfQRgEG//9NG3JhA1WOKwe0KcmVSmGj1BJNwM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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