SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27e6506f587bbaf8e9630c3b08ba0bb756dab8bcfef950d8566e52e5aadd3ef4' 
  AND token = 'ZGKtoXMz7D8sW0O9qyRoOsJx83EmwnDLYg8J22VSIW8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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