SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7bced04d40afef54d1c50671c04cba5db4b182d8fdae6dff33378a9eb7569649' 
  AND token = 'k0zjAhER7YsZvRAac8IeKc22p5p5BT1F50vhWGa8Jnw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}