SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22c6396da94e5fe3bd200605baf2903914182e0e10654e8df1577d468d7fde41' 
  AND token = 'VOuE6hqh0zQYzN2SySGEviA+OCzjgKjLYTgsK6RH/g4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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