SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90dfac0eb703b440e13f1af17d6f793897fd8883fc2d9612fa63462fcc9eb4bc' 
  AND token = 'fiEThNS5ilcIZM/4HpKqKE0YeHNSEdgud5MF/kTzM30=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}