SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2eb083e8c7f4015852ac5906856874a7d2b161fe405f683495c1ae37fd57fd8f' 
  AND token = '0lstJ8hcHKXTV4rJelhxDTUPg+5Qqf56DOWDQ1N9Geg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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