SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '16b295d87de4f951def6a5afbd08e156df3496ab3962237d415c0e2bc7d18955' 
  AND token = 'lPS3HjTVJmgBSW10tdDw2F0KIGKKEeUDrqiG6ih2Eyg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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