SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd3209ad1e123b3e6335c203af25db331eb63222ee11d33dad3a2007b01ddbdbf' 
  AND token = '8iZvh2z/Pe53wx6KnpKVKxoN5TGpIVX/erzjs3kUCZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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