SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ffabbf1d1db89b4ec7d7dd56a63dc320d835ab0a902821ffe0d649cf42d1194' 
  AND token = 'g2WxG83VTYdXQKaEXkCTrkeU/vOHo/oXIaN83Jca5p0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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