SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f0cfefe904d2246f03c5292009f38fc55b0c173154163146ed062bbc75a3a081' 
  AND token = 'o94ez7ntgPqNQz4AIQyw1XzXnlhyHAVagvsOnwBuqVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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