SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aec313f00614c00df3e7cb6aba7299433b02696f9f9adbb845f7bf9d86c03b7a' 
  AND token = 'WXGHTNrURogFUD5wmcaXNzKGa22dzvgegdVQuD6QRIU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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