SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e0525c7446e2cac61a8d42c0555d8515a3c03fe1e89382e3d87879d26a192f3f' 
  AND token = 't6uL9jr9FOI0URbh0G2/17Yw1Y4n5UrbG6Y5wp4XbSI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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