SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'afb6fb09f9ca353c6942ad03d3057252e7dfbcc285f248a95e719124fd8d3a4d' 
  AND token = 'NMbxmpXw36RU+Y3tB4N2M4LaFtnjkVax8ptgIuK2JRQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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