SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bebf77da8007d5dc4bc1a4cc4df9aa7d1b16ec8fd9e00ed6fc589c637b93f17e' 
  AND token = 'PYNNivXVAlbQ+8D0oaJl84jnvnr4EeWWFKlW54Xz/Aw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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