SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '478546f5792eee4305c582fb75f228217f0c5cfa2dc5336da3daf4f10f8aca5e' 
  AND token = '6N4DBvz0Ml2l3g1YL3aABSrNtzZAlqfTdISZNKN3nRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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