SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52b30a43fa2ea7d1138648405bbb9f7a6e0471d9cf4302c979f65c8131c7e669' 
  AND token = 'pVhQQcTOFbojfaa82x7OYSBNCydUgBwLu9EPutTNW8I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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