SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '248d316f3ad0c7bbd6537074d4dcf22818dabcff627ad519fd45077f9c863fad' 
  AND token = 'cjnYWezRzuE/OEOrVYLVKm4Il4EFlweVFIKM54mGgfE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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