SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3fc6d75689502cea2481b1e7c986bf997234e6f3c0dee59976e7f134f520a363' 
  AND token = 'FDtJesbEjBZqXcXiDhWq7ad+X9zq4eBwwaX2vt4xxZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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